JP5861805B2 - Transformer, power supply device, and method of manufacturing transformer - Google Patents

Description

  The present invention relates to a transformer used for a switching power supply, an insulating inverter, and the like, a manufacturing method thereof, and a power supply device.

  A switching power supply whose output exceeds 1 kW and a power supply device such as an insulated inverter are driven at approximately 10 kHz to 80 kHz from the viewpoint of efficiency. A typical example of a transformer core material used in a switching power supply or the like driven under such conditions is Mn—Zn ferrite. From the viewpoint of miniaturization, soft magnetic alloy materials such as amorphous materials and nanocrystalline materials with high saturation magnetic flux density are also used. The transformer is configured such that a UU-shaped or EE-shaped magnetic core is abutted in a coil form that is formed by winding a lead wire around a bobbin in advance. A configuration that forms a magnetic path is common.

  In the above configuration, a gap is generated at the butting surface even if it is slight. In particular, when a cut core formed of a soft magnetic alloy ribbon having a low specific resistance is used, such a gap is generated, thereby increasing loss due to leakage magnetic flux. For this reason, when the soft magnetic alloy ribbon is used in the form of a cut core, the operating magnetic flux density cannot be made sufficiently high, and it is difficult to say that a design that fully utilizes the characteristics of the soft magnetic alloy material can be made.

  On the other hand, there is a transformer using a metal magnetic material that does not cut, such as a toroidal transformer. However, since the winding in the toroidal transformer is a manual work, there are problems such as poor workability and large variations in characteristics. Although it is a technique related to a line filter instead of a transformer, for example, Patent Document 1 discloses a technique for efficiently winding a non-cut magnetic core that is not cut. In the configuration disclosed in Patent Document 1, a bobbin with a gear is attached to a Japanese-shaped closed magnetic path magnetic core, and winding work is performed using the gear. Thereby, winding work can be performed more easily.

Japanese Utility Model Publication No. 4-85714

  However, in the configuration described in Patent Document 1, since the primary coil and the secondary coil are separated from each other in the axial direction of the middle leg, the coupling coefficient between the primary coil and the secondary coil is reduced, and the copper loss is also increased. Resulting in. Therefore, this configuration is unsuitable for a transformer.

  For this reason, conventionally, it has been difficult to provide a transformer that makes use of the characteristics of the magnetic alloy ribbon, ie, high saturation magnetic flux density, while ensuring the workability of the winding.

  Therefore, in view of the above problems, the present invention secures the workability of the winding, and uses a small and lightweight transformer utilizing the high saturation magnetic flux density of the magnetic alloy ribbon, a power supply device using the transformer, and the transformer An object is to provide a manufacturing method.

  A transformer according to an embodiment of the present invention is configured by winding or laminating a magnetic alloy ribbon, and includes a non-cut magnetic core that forms a closed magnetic circuit, a protective member that covers at least a part of the magnetic core, a primary coil, and a secondary coil. A secondary coil and at least one bobbin provided for winding the conductive wire constituting the primary coil and the secondary coil, and the at least one bobbin has a circumferential surface around which the conductive wire is wound. A cylindrical portion, a pair of flange portions provided so as to sandwich the peripheral surface in the axial direction of the cylindrical portion, and an outer side of at least one of the pair of flange portions, provided with a gap from the flange portion. At least one gear portion, and is supported rotatably around the protective member in the cylindrical portion, and a winding portion of a conducting wire constituting the primary coil and the secondary core Windings of lead constituting the Le and are alternately arranged in the radial direction of the cylindrical portion.

  In one embodiment, the at least one bobbin includes a plurality of bobbin members combined so as to sandwich the protection member around the protection member, and each of the plurality of bobbin members includes a part of the cylindrical portion. Contains.

  In one embodiment, in each of the at least one bobbin, each lead wire of each of a plurality of winding portions of the lead wire constituting the primary coil, which is overlapped via a winding portion of the lead wire constituting the secondary coil, is The conductors of the plurality of winding parts of the conductor wire that are connected in parallel on the outside of the flange and that are stacked via the winding part of the conductor wire that constitutes the primary coil are , And connected in parallel outside the flange.

  In one embodiment, the at least one bobbin includes a plurality of bobbins, and the primary coil and the secondary coil are respectively divided into a plurality of sub-coils connected in parallel or in series and arranged on the plurality of bobbins. Has been.

  In one embodiment, the magnetic alloy ribbon has a magnetic characteristic that a saturation magnetic flux density Bs is 1.0 T or more and a ratio Br / Bs of a residual magnetic flux density Br to the saturation magnetic flux density Bs is 0.3 or less. Have.

  In a certain embodiment, the sheet-like insulator is arrange | positioned between the winding part of the said primary coil, and the winding part of the said secondary coil.

  In one embodiment, at least one of the pair of flange portions is provided with a conductor passage portion for arranging an end portion of the conductor wire wound around the circumferential surface of the cylindrical portion outside the flange portion. And the said conducting wire passage part contains the notch part or hole which lets the said conducting wire pass in the position inside radial direction rather than the outer periphery of the said collar part.

  In one embodiment, the conducting wire passage portion includes a pair of notch portions arranged so as to sandwich the cylindrical portion when viewed from the axial direction of the cylindrical portion, and an end portion of the conducting wire constituting the primary coil is, The one end of the pair of notches is arranged outside the flange through one of the notches, and the end of the conducting wire constituting the secondary coil is out of the pair of notches. It is distribute | arranged to the outer side of the said collar part through the other notch part.

  In one embodiment, the at least one bobbin is configured such that, when the bobbin is rotated, an end portion of the conducting wire disposed outside the flange portion through the conducting wire passage portion is radially outside the cylindrical portion. It further has a regulation part which has a field which prevents moving toward.

  In a certain embodiment, it has the rod-shaped protrusion which protrudes toward the axial direction outer side of the said cylindrical part from the surface of the said collar part.

  In one embodiment, the protective member is a case that houses the magnetic core.

  In one embodiment, the at least one bobbin has an outer peripheral surface between the flange portion and the gear portion, and the diameter of the outer peripheral surface and the diameter of the peripheral surface of the cylindrical portion are the same. .

  A power supply device according to an embodiment of the present invention is a power supply device including any one of the above transformers.

  In one embodiment, the power supply device is an insulated inverter or an insulated switching power supply having a drive frequency of 10 to 50 kHz and an output of 5 kW or more.

  A method of manufacturing a transformer according to an embodiment of the present invention includes a first step of attaching a protective member to an uncut magnetic core that forms a closed magnetic path, and is constituted by winding or laminating a magnetic alloy ribbon. A cylindrical portion having a peripheral surface to be rotated, a pair of flange portions provided so as to sandwich the peripheral surface in the axial direction of the cylindrical portion, and the flange portion on the outer side of at least one of the pair of flange portions And at least one bobbin having at least one gear portion spaced from each other, and a second step of rotatably mounting the cylindrical portion around the protective member in the cylindrical portion, and the gear portion through the gear portion. A third step of winding a conducting wire on the peripheral surface of the cylindrical portion by rotating a bobbin, thereby forming a primary coil and a secondary coil around the cylindrical portion, and of Degree includes a wound portion of the wire constituting the primary coil, and a winding portion of the lead constituting the secondary coil, the step of alternately formed in the radial direction of the cylindrical portion.

  In one embodiment, the at least one bobbin includes a plurality of bobbins, and the primary coil and the secondary coil are divided into a plurality of sub-coils connected in parallel or in series, respectively, to the plurality of bobbins. Be placed.

  In one embodiment, at least one of the pair of flanges is formed with a pair of notches disposed so as to sandwich the cylindrical part when viewed from the axial direction of the cylindrical part, and the third The step of winding the conductive wire in a state in which the end portion of the conductive wire constituting the primary coil is arranged on the outside of the flange portion from one cutout portion of the pair of cutout portions; A step of winding the conductive wire in a state where an end portion of the conductive wire constituting the secondary coil is arranged on the outside of the flange portion from the other cutout portion of the pair of cutout portions.

  In a certain embodiment, when forming the winding part of the said conducting wire in the said 3rd process, the edge part of the said conducting wire is arrange | positioned in the clearance gap between the said collar part and the said gear part.

  In one embodiment, the at least one bobbin further includes a restricting portion having a surface that prevents an end portion of the conducting wire disposed outside the flange portion from moving toward the radially outer side of the cylindrical portion. And in the said 3rd process, when forming the winding part of the said conducting wire, the edge part of the said conducting wire is distribute | arranged to the position inside the said control part in the radial direction of the said cylindrical part.

  In one embodiment, the at least one bobbin has a rod-like protrusion that protrudes from the surface of the flange portion toward the outside in the axial direction of the cylindrical portion, and the third step includes an end portion of the conducting wire. A step of entwining the protrusion.

  In one embodiment, the transformer has a case for accommodating a magnetic core, and the case may be an assembly of an upper case and a lower case. The case may have a linear portion along the magnetic path of the magnetic core, and the bobbin is rotatably supported by the linear portion of the case in the cylindrical portion.

  Further, in the transformer, the shape of the cross section perpendicular to the magnetic path direction of the magnetic core is a rectangle, and the long core side of the rectangle is arranged on the joint portion side of the upper case and the lower case, the magnetic core The shape of the cross section accommodated in the case and perpendicular to the magnetic path direction of the magnetic core may be closer to a square or square than the shape of the cross section of the magnetic core. Alternatively, the cross-sectional shape of the magnetic core itself may be square, and the cross-section of the case containing the magnetic core may also be square.

  According to the embodiments of the present invention, it is possible to ensure workability of windings, and to provide a small and lightweight transformer, a power supply device using the transformer, and a method for manufacturing such a transformer.

It is a perspective view showing an embodiment of a transformer concerning the present invention. (A) And (b) is a disassembled perspective view of the case, magnetic core, and bobbin which are used for the embodiment of the transformer concerning the present invention. It is a figure which shows the collar part of the bobbin used for embodiment of the transformer which concerns on this invention, (a) is a side view when it sees from the direction perpendicular | vertical to the axial direction of a cylindrical part, (b) and (c) are cylinders It is a side view when it sees from the axial direction of a part. It is a cross-sectional schematic diagram which shows one Embodiment of the trans | transformer which concerns on this invention. It is a cross-sectional schematic diagram which shows other embodiment of the trans | transformer which concerns on this invention. It is a cross-sectional schematic diagram which shows other embodiment of the trans | transformer which concerns on this invention. It is a cross-sectional schematic diagram which shows other embodiment of the trans | transformer which concerns on this invention. It is a graph which shows the relationship between an applied magnetic flux density and a core loss. (A) is a cross-sectional schematic diagram which shows the winding state of the primary coil and secondary coil in the trans | transformer of a comparative example, (b) is winding of the primary coil and secondary coil in one Embodiment of the transformer which concerns on this invention. It is a cross-sectional schematic diagram which shows a state, (c) is a figure which extracts and expands and shows the part of the coil of the cross-sectional schematic diagram of (b). It is a graph which shows the frequency dependence of effective resistance. It is a graph which shows the relationship between the temperature of a magnetic core surface and a coil surface, and drive time.

  The configuration of the transformer according to the embodiment of the present invention will be described below.

  A transformer according to an embodiment of the present invention includes an uncut magnetic core formed by winding or laminating magnetic alloy ribbons to form a closed magnetic circuit, a protective member covering at least a part of the magnetic core, a primary coil, and a secondary A coil, and at least one bobbin provided to wind a conducting wire constituting the primary coil and the secondary coil and rotatably supported around the protection member. The transformer according to the embodiment of the present invention is configured using a magnetic core of an uncut closed magnetic circuit in order to make the most of the characteristics of the magnetic alloy ribbon having a high saturation magnetic flux density.

  The protective member is typically a case that accommodates a magnetic core, and the case is an assembly including a plurality of case members that are fixed to each other so as to form a space that accommodates the magnetic core, for example. It's okay. The case may have a straight portion along the magnetic path of the magnetic core. Further, the bobbin includes a cylindrical portion having a circumferential surface around which the conducting wire is wound, a pair of flange portions provided so as to sandwich the circumferential surface in the axial direction of the cylindrical portion, and at least of the pair of flange portions On one outer side, it has at least one gear part provided at intervals with the collar part. In this configuration, the cylindrical portion of the bobbin is rotatably supported by the linear portion of the case.

  With this configuration, winding by rotation through the gear portion (hereinafter also referred to as gear winding) is possible, so that workability of the winding when using an uncut magnetic core can be ensured.

  Furthermore, in the transformer according to the embodiment of the present invention, the winding portion of the conducting wire constituting the primary coil and the winding portion of the conducting wire constituting the secondary coil are alternately arranged in the radial direction of the cylindrical portion. Thus, by adopting the above-described configuration different from the configuration of the gear winding employed in the conventional line filter as shown in Patent Document 1, the coupling between the primary coil and the secondary coil is enhanced, and the gear is A configuration suitable for applying a winding to a transformer can be provided.

  Hereinafter, a transformer and a manufacturing method thereof according to an embodiment of the present invention will be described more specifically with reference to the drawings. However, the present invention is not limited to this. Moreover, the structure demonstrated in each embodiment is applicable also in other embodiment, unless the meaning of other embodiment is impaired, In that case, the overlapping description is abbreviate | omitted suitably.

  FIG. 1 is a perspective view showing a transformer 100 according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of a case, a magnetic core and a bobbin used in the embodiment shown in FIG. The transformer 100 is wound with a magnetic core 5, a case 1 as a protective member that houses and protects the magnetic core 5, a primary coil 2 and a secondary coil 3, and a conductive wire constituting the primary coil 2 and the secondary coil 3. And a bobbin 4 for rotation.

  As described above, the magnetic core 5 is formed by winding or laminating a magnetic alloy ribbon. The magnetic alloy ribbon used is, for example, an Fe-based amorphous alloy ribbon, a Co-based amorphous alloy ribbon, or an Fe-based nanocrystalline alloy ribbon obtained by quenching a molten metal. Co-based amorphous alloy ribbons with relatively low saturation flux density have saturation flux densities of about 0.55 T or more. These magnetic alloy ribbons have a higher saturation flux density than ferrite and are small in transformer size. It is advantageous to make. In order to make full use of this advantage, the magnetic core 5 is configured as an uncut core. Uncut means that there is no cut portion in the middle of the magnetic path of the magnetic alloy ribbon. Since the uncut magnetic core forming the closed magnetic path does not generate a magnetic gap, the influence of leakage magnetic flux is eliminated, and the transformer can be driven with a high operating magnetic flux density.

  The uncut magnetic core 5 may be a wound magnetic core formed by winding a magnetic alloy ribbon in an annular shape, or may be a laminated magnetic core in which a plurality of magnetic alloy ribbons punched into a predetermined shape are stacked. The magnetic core 5 shown in FIG. 2 is a rectangular annular magnetic core constituting a rectangular magnetic path, but the shape of the magnetic core is not limited to this. However, in order to accommodate in the case 1 which has the linear part 6 mentioned later, it is suitable to use the thing of a shape which has a linear part in the part. For example, a magnetic core such as a rectangular ring (b-shaped), a race track, or a rectangular ring with a middle leg (day-shaped) can be used. A rectangular ring or racetrack-shaped magnetic core is sometimes called a bipod magnetic core, and a rectangular ring with a middle leg is sometimes called a tripod magnetic core. Typically, the former has two straight portions as legs, and the latter has three straight portions as legs.

  A simple annular magnetic core such as a rectangular ring (b-shaped) or a racetrack is particularly preferably manufactured in the form of a wound core from the viewpoint of productivity. A rectangular core (triple core) with a middle leg can be obtained by a method of laminating magnetic alloy ribbons punched into such a shape or a method of juxtaposing two wound cores. In the present specification, the term “rectangular” indicating the shape of the magnetic core is not limited to a perfect rectangle, but is a shape having a rounded portion (curved surface portion) that is inevitably generated when a magnetic alloy ribbon is wound. Is also used.

  The composition and characteristics of the magnetic alloy ribbon constituting the magnetic core 5 are not limited thereto. However, the magnetic alloy ribbon used has a magnetic characteristic that the saturation magnetic flux density Bs is 1.0 T or more and the ratio of the residual magnetic flux density Br to the saturation magnetic flux density Bs is Br / Bs is 0.3 or less. preferable. The reason will be described below.

  In an insulated switching power supply or the like, the transformer circuit can be miniaturized by operating the transformer in a bipolar manner. In bipolar operation, when the power supply is stopped, the magnetic flux density of the transformer core is kept between + Br and -Br, and does not necessarily settle to the origin of BH (biased), and the operation start point is the maximum. + Br. In order to avoid magnetic saturation, it is not usually performed to raise the operating magnetic flux density to a level comparable to the saturation magnetic flux density Bs in consideration of a design safety margin. Therefore, the transformer can be designed more compactly by using a magnetic core having as low a residual magnetic flux density as possible, more precisely ΔB (= Bs−Br), in other words, a small ratio Br / Bs. As a countermeasure against the demagnetization, for example, there is a method of reducing Br by providing a gap in the magnetic core.

  Magnetic metal ribbons such as Fe-based amorphous materials have a higher saturation magnetic flux density than ferrite, which is advantageous for miniaturization of transformers. Then, the core is cut and the loss increases as described above, and there is a problem that high Bs cannot be utilized. Therefore, by performing a heat treatment in a magnetic field on the magnetic metal ribbon, anisotropy is given in a direction perpendicular to the magnetic path (that is, by forming an easy magnetization axis in the perpendicular direction). May be reduced. Anisotropy in the direction perpendicular to the magnetic path by heat treatment in a magnetic field is advantageous because the ratio Br / Bs of the residual magnetic flux density Br to the saturation magnetic flux density Bs can be reduced. From the viewpoint of securing a large ΔB, as described above, the magnetic alloy ribbon has a saturation magnetic flux density Bs of 1.0 T or more and a ratio Br / Bs of the residual magnetic flux density Br to the saturation magnetic flux density Bs is 0.3. The following is preferable. The upper limit of Bs is not particularly limited, but for example, Bs of Fe amorphous material used for practical use is 1.8 T or less.

  The case (protective member) 1 is an assembly of two case members, an upper case 1a and a lower case 1b, which are divided in the vertical direction (z direction in the figure). Note that the concept of “upper and lower” here is for convenience to show the directionality during assembly. A space for accommodating the magnetic core 5 is formed in the lower case 1b, and the upper case 1a and the lower case 1b are fitted so as to cover the space with the upper case 1a. In the embodiment shown in FIG. 1, the joint portion (overlapping portion) between the upper case 1 a and the lower case 1 b is in the direction perpendicular to the axis of the annular case 1, that is, on the side surface in the xy direction. The case 1 has a pair of linear portions 6 along the magnetic path of the magnetic core 5 (along the x direction in the figure). The case 1 is a rectangular annular case configured following the shape of the magnetic core 5 and also has a straight line portion along the y direction in the figure. Note that the four corners of the case 1 are formed with protruding portions in the y direction as fixing portions for fastening the upper case 1a and the lower case 1b. Even when such protruding portions or rounded corner portions are formed, the overall shape of the case is handled as a rectangle.

  Even if the magnetic core of the magnetic alloy ribbon is a wound core or a laminated core, the cross section perpendicular to the magnetic path is usually rectangular. Therefore, the internal shape of the cross section of the case that accommodates it is also generally rectangular. The outer shape of the case cross section may be other than a rectangle, but is preferably rectangular from the viewpoint of simplifying the case structure.

  The outer shape of the cross section of the straight portion of the case supporting the cylindrical portion of the bobbin can be circular or n-gonal (n is a natural number of 5 or more). There are also great advantages. When the transformer is driven, the magnetic core generates heat, but since the heat radiation is blocked by the coil in the portion covered with the coil, the temperature of the transformer becomes high. On the other hand, when a case having a rectangular cross-section is used, a large space is formed between the outer surface of the case and the inner surface of the bobbin, leading to the outside of the bobbin. Therefore, heat dissipation is promoted, and the temperature rise of the transformer can be suppressed. .

  In the embodiment shown in FIG. 1, the shape of the cross section perpendicular to the magnetic path direction of the magnetic core 5 is rectangular, and on the joint side of the upper case 1 a and the lower case 1 b, that is, on the inner peripheral side and the outer peripheral side of the annular case, The magnetic core 5 is accommodated in the case 1 so that the long side of the rectangular cross section of the magnetic core 5 is disposed. In order to shorten the total length of the winding wound around the bobbin, it is preferable that the cross-sectional shape of the case disposed in the cylindrical portion inside the bobbin is as close to a square as possible. However, in the embodiment shown in FIG. 1, since the upper case 1a and the lower case 1b are connected so as to partially overlap each other, when the case is made thin and downsized, the upper case 1a and the lower case 1b The thickness of the case of the joint portion is relatively larger than that of other portions. On the other hand, if a magnetic core having a rectangular cross section is prepared and arranged so that its long side is on the joint side (side surface side), the thickness of the case increases as described above. It can be offset by the dimensional difference from the side. With such a configuration, the cross-sectional shape of the case 1 perpendicular to the magnetic path direction of the magnetic core 5 is closer to a square than the cross-sectional shape of the magnetic core 5 (the ratio of the short side to the long side is close to 1). Or it may be square. Of these, a square is most preferable, and in the configuration of FIG. 1, the cross-sectional shape of the case 1 is a square. However, regardless of the form, the cross section of the magnetic core may be substantially square. Also in this case, by making the thickness of the case 1 uniform, the cross-sectional shape of the outer surface of the case 1 can be designed to be substantially square like the magnetic core.

  The case 1 is used for the purpose of protecting the magnetic core 5 and ensuring insulation. The material of the case is not particularly limited as long as it is suitable for such purposes, but for example, a resin such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), or the like may be used. it can.

  Although the case where the case 1 as the protective member is configured by combining a plurality of members (upper case and lower case) has been described above, the present invention is not limited to this. For example, you may use the case which consists of an open type single member which has the accommodation space which adapts a magnetic core. In this case, the magnetic core may be prevented from being detached from the case by winding the insulating tape after the magnetic core is accommodated in the case. Moreover, in the form demonstrated above, although case 1 which has the space which accommodates the whole magnetic core 5 is used, it is not restricted to this, The form which covers only a part of magnetic core may be sufficient. However, it is preferable that the protective member is provided so as to cover the magnetic core at least in a portion where the bobbin is attached. As a result, as will be described later, when the bobbin is rotated around the magnetic core, the possibility that the magnetic core is damaged by the interposed protective member can be reduced. Further, when the strength is insufficient with only the protective member, the strength of the magnetic core itself may be improved by impregnating with resin.

  Thus, although various aspects can be adopted as the protective member, if the case is used, the magnetic core can be protected in a relatively simple process, and the part to which the bobbin is attached is reliably protected, The bobbin can be smoothly rotated.

  The bobbin 4 includes a cylindrical portion 7 having a peripheral surface for winding a conducting wire, and a pair of flange portions 8 arranged so as to sandwich the peripheral surface of the cylindrical portion 7 in the axial direction on both ends of the cylindrical portion 7. Have. The flange portion 8 has a disk shape whose outer diameter is larger than the outer diameter of the cylindrical portion 7, and defines a winding portion of the conducting wire. Further, in the bobbin 4, a gear portion 9 for receiving the rotational force is provided between the flange portion 8 and the outside of the flange portion 8 (on the opposite side to the winding portion of the conducting wire in the x direction in the figure). It is provided at intervals. That is, the gear portion 9 is provided so as to be separated from the flange portion 8 adjacent thereto in the axial direction (x direction) of the cylindrical portion 7. In the embodiment shown in FIG. 1, the gear portion 9 is provided at the end of the cylindrical portion 7. In addition, a peripheral surface (sometimes referred to as an outer peripheral surface) having the same diameter as the peripheral surface of the cylindrical portion 7 is provided between the flange portion 8 and the gear portion 9.

  The bobbin 4 is also configured by an assembly of two divided portions (sometimes referred to as bobbin members) 4a and 4b, similar to the case 1 described above. The two divided portions 4a and 4b are combined so as to sandwich the case 1, and a connecting portion is formed along the axial direction of the cylindrical portion. The division parts 4a and 4b may be fixed with respect to each other. In this configuration, the divided portions 4a and 4b each have a semi-cylindrical portion that constitutes the cylindrical portion 7, and each semi-cylindrical portion is combined so as to sandwich the case 1 to rotate around the case 1. Possible bobbins are obtained. The bobbin 4 may be constituted by three or more bobbin members arranged so as to surround the case 1, but is constituted by two bobbin members from the viewpoint of securing the number of parts and strength. Is preferable.

  The inner peripheral side of the cylindrical portion 7 of the bobbin 4 and the corner of the case 1 are gently in contact with each other or are arranged with a slight clearance therebetween, and the bobbin 4 is rotated around the straight portion 6 of the case 1 in the cylindrical portion 7. It is supported movably. The gear portion 9 has a common axis with the cylindrical portion 7, and the cylindrical portion 7 rotates integrally with the gear portion 9. Therefore, by applying a driving force of a motor or the like to the gear unit 9, the winding can be wound and workability of the winding is ensured. In the embodiment shown in FIG. 1, the gear portions are respectively provided on both end sides of the cylindrical portion 7, but can be provided only on one side. However, in order to rotate the bobbin 4 stably, the gear part is preferably provided on both sides of the cylindrical part.

  In the embodiment shown in FIG. 1, the notch portions 10 are provided on both sides of the flange portion 8 on both ends of the cylindrical portion 7 with the hollow portion of the cylindrical portion 7 as viewed from the axial direction (x direction) of the cylindrical portion 7. It has been. The notch portion 10 is typically provided at a symmetrical position with respect to the central axis of the cylindrical portion 7 (or at a position that is 180 ° different in the circumferential direction in the ring-shaped flange portion 8). In this configuration, the winding end (lead) of the primary coil 2 is drawn out from one of the cutout portions 10 on both sides, and the winding end (lead) of the secondary coil 3 is pulled out of the cutout portion 10. Of these, it is pulled out from the notch on the other side. In the embodiment shown in FIG. 1, a total of four notches 10 are provided in each of the flanges 8, but among the notches 10 on both sides across the opening of the cylindrical portion 7. One is not shown because it is behind a bobbin. Further, in each coil, both winding ends are drawn out from cutout portions formed in separate flanges, but each winding end (lead) is omitted in the drawing for convenience. Insulating properties between the primary coil and the secondary coil in the winding end process are enhanced by separating the winding positions of the winding ends of the primary coil and the secondary coil by 180 ° about the axis of the cylindrical portion 7.

  Without being limited to the above-described notch, a hole may be provided in the flange, and the winding end of each coil may be led out of the hole from the hole. However, a configuration in which a notch is provided and the winding end is drawn out from this is preferable because the workability of the winding is high.

  In addition, in this specification, said notch part and hole part may be collectively called a conducting wire passage part. Thus, the end part of a conducting wire is pulled out to the outer side of a collar part through the conductor passage part provided in the collar part. The conducting wire passage portion is formed so that the conducting wire can pass through a position radially inward from the outer peripheral edge of the flange portion.

  By providing the conducting wire passage part (for example, a notch part) as described above, the winding end of each coil can be pulled out in the axial direction as it is without being routed unnecessarily in the radial direction of the cylindrical part 7. From this point of view, it is preferable that the notch portion 10 extends from the outer peripheral edge of the flange portion 8 to the outer peripheral surface of the cylindrical portion 7 as in the embodiment shown in FIGS. Although the shape of the notch 10 is not particularly limited, for example, it may be formed in a slit shape having a sufficient width for drawing out the conducting wire.

  In the embodiment shown in FIG. 1, a pair of notches 10 are provided for one flange, but two pairs may be provided depending on the configuration of the coil. However, from the viewpoint of securing the space between the drawn winding ends, it is preferable that only one pair of notches is formed per one hook portion.

  The notch portion 10 is provided in the flange portion 8 on both ends of the cylindrical portion 7, but by pulling out the winding end at the beginning of winding and the winding end at the end of winding of one coil from one flange portion, It is also possible to provide a notch in only one of the flanges 8 on both ends of the cylindrical portion 7. However, from the viewpoint of ensuring insulation, the notch portion is avoided from concentrating on one of the flange portions, and the notch portions 10 are distributed and arranged on the flange portions 8 on both ends as in the embodiment of FIG. It is preferable.

  As described above, the bobbin preferably has a structure that can restrict the movement of the winding end of each coil arranged (drawn) outside the collar portion so as not to be scattered during the winding operation. The winding end of the coil disposed outside the collar portion may be an end portion in a state of being pulled out from the cylindrical portion to the outside of the collar portion when winding the coil. It may be the end of winding start or winding end of a previously wound coil. In the present specification, the winding end portion that is arranged outside the collar portion at the beginning of winding as described above may be expressed as being “drawn” outside the collar portion.

  FIG. 3 shows an exemplary embodiment of the restriction structure described above. FIG. 3A is a view of one end side of the cylindrical portion 7 as viewed from a direction (y direction) perpendicular to the axial direction (x direction) of the cylindrical portion 7. FIG. 3B is a view of the bobbin as seen from the axial direction (x direction) of the cylindrical portion 7, and the gear portion is omitted for the sake of convenience and only the collar portion is shown. In the embodiment shown in FIGS. 3 (a) and 3 (b), the rod-shaped protrusion 11 is provided so as to protrude from the surface of the flange portion 8 toward the outside in the axial direction (x direction) of the cylindrical portion 7.

  The rod-shaped protrusion 11 is used to limit the movement of the winding end (conductive wire end portion) of each coil to the radially outer side during gear winding. For example, the winding end pulled out from the notch portion 10 is drawn around the outer peripheral surface having the same diameter as the cylindrical peripheral surface in the space between the flange portion 8 and the gear portion 9. At that time, the winding end is routed so as to be disposed at a position radially inward of the protrusion 11, that is, at a position between the peripheral surface of the cylindrical portion 7 (or the above-described outer peripheral surface) and the rod-shaped protrusion 11 in the radial direction. The protrusion 11 can function as a pressing member that prevents the winding end from moving outward in the radial direction. For example, in the form shown in FIGS. 3A to 3C, the end portion of the conducting wire drawn out from the notch portion 10 on one side is placed on the outer peripheral surface to the protrusion 11 located in the vicinity of the other notch portion. If the coil winding end moves toward the outside in the radial direction when the gear is wound, the side surface of the projection 11 (the surface on the center side of the cylindrical axis) comes into contact with the coil. Further movement of the winding edge can be prevented.

  Further, the winding end drawn out from the notch 10 to the outside of the flange 8 is drawn around the protrusion 11 after drawing the space (space on the outer peripheral surface) between the flange 8 and the gear 9. A configuration (wrapping around the protrusion 11) is also possible. The height of the protrusion 11 from the surface of the flange portion 8 is set in a range that does not reach the gear portion 9. Thereby, it can prevent that the protrusion 11 does not become an obstruction at the time of winding work.

  In addition, not only the protrusion 11 but the restriction | limiting part of another form may be provided in the space between the collar part and gear part of a bobbin. The restricting portion only needs to have a surface that prevents the end of the conducting wire extending outside the collar from moving radially outward when the bobbin is rotated. For example, in the circumferential direction of the collar It may be a plate-like portion extending along the width. Further, the restricting portion is not limited to the one protruding from the collar portion, and may be one protruding from the gear portion.

  In the embodiment shown in FIGS. 3A and 3B, the radial position of the protrusion 11 is a position spaced from the outer edge of the flange 8 toward the center. However, the radial position of the protrusion 11 is not limited to this. As shown in FIG. 3C, the protrusion 11 ′ can be arranged at the radial end (outer edge) of the flange 8. Such a configuration has an advantage that a large space can be secured for accommodating the winding end and the winding end can be easily routed.

  As described above, in order to ensure the ease of winding end processing such as terminal connection after winding work, the length of the winding end pulled out from the notch of the flange has a certain length. Sometimes it is better to be. In this case, the position in the circumferential direction where the protrusion 11 is provided may be a position close to the other notch, not the notch from which the winding end whose movement is to be restricted by the protrusion 11 is led out. In the embodiment shown in FIG. 3, the notch portion 10 and the protrusion 11 are disposed on both end sides separated by 130 ° or more in the circumferential direction of the half portion 8 a (8 b) of the flange portion. Since the notch and the protrusion may be arranged in a state where the halves are combined, the notch and the protrusion may be arranged near the center in the circumferential direction of each of the halves. However, if the protrusion 11 is positioned at the end in the circumferential direction of the halved portion 8a (8b) as in the embodiment shown in FIG. 3, it is easy to form a bobbin with a protrusion.

  The material of the bobbin 4 is not particularly limited, but as in the case 1, for example, a resin such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS) can be used.

  Next, the structural example of the coil applied to embodiment of FIG. 1 is demonstrated. FIG. 4 is a schematic cross-sectional view showing an embodiment of a transformer. The winding part Np of the conducting wire constituting the primary coil 2 and the winding part Ns of the conducting wire constituting the secondary coil 3 are alternately arranged in the radial direction (y direction in FIG. 4) of the cylindrical part 7. The plurality of winding portions Np constituting the primary coil 2 are connected in parallel to each other, and the plurality of winding portions Ns constituting the secondary coil 3 are also connected in parallel to each other. Since the winding part Np of the primary coil and the winding part Ns of the secondary coil are wound around the same part of the magnetic core 5, the lead wire of the primary coil and the lead wire of the secondary coil are brought into close contact with each other to constitute the coil. The coupling between the coils is increased. By realizing a transformer with a high coupling coefficient, an increase in effective resistance (AC resistance) can be suppressed. That is, as shown in FIG. 4, according to the configuration in which the winding portions of the primary coil and the winding portions of the secondary coil are alternately arranged in the radial direction of the cylindrical portion, an effect of suppressing an increase in copper loss can be obtained. In addition to the effect of reducing the gap loss by using the above-described uncut magnetic core, it contributes to the loss reduction and miniaturization of the transformer.

  In the winding parts Np and Ns, the conducting wire is wound from one end side of the cylindrical part 7 to the other end side (x direction). In each winding part, it is possible to wind the conductive wire in the radial direction, but for the purpose of improving the coupling between the coils, each winding part can be configured by one layer without overlapping the conductive wire. preferable.

  Further, as the configuration of the winding, when the winding portions Np and Ns are alternately arranged in the radial direction of the cylindrical portion 7, the winding portions Np and Ns are arranged one by one, and the primary coil 2 and the secondary coil 3 can be configured. However, as in the embodiment shown in FIG. 4, the primary coil 2 and the secondary coil 3 are each divided into a plurality of winding parts connected in parallel, and the plurality of winding parts are divided into the primary coil and the secondary coil. It is advantageous that the secondary coils are alternately arranged in the radial direction of the cylindrical portion. With this configuration, the resistance of the coil is reduced and the coupling between the primary coil 2 and the secondary coil 3 is enhanced. The connection form of the divided coils is not limited to parallel connection, and series connection is also applicable. It is more advantageous for coupling between the coils to divide and arrange them alternately as described above, rather than winding the conductive wires in a superimposed manner.

  The configuration of the coil described above can also be applied to a transformer using a rectangular core with a middle leg (sun-shaped). FIG. 5 is a schematic cross-sectional view showing an embodiment thereof. Although the bobbin 14 provided with the primary coil 12 and the secondary coil 13 is different from the embodiment shown in FIG. 4 in that the bobbin 14 is arranged on the middle leg of the magnetic core 15, the configuration of the coil and bobbin is the same as that of the embodiment shown in FIG. Since it exists, description is abbreviate | omitted.

  In the magnetic core of the form shown in FIG. 5, for example, two annular magnetic cores obtained by winding or laminating a magnetic alloy ribbon are arranged adjacent to each other in the case, and the adjacent portions are used as middle legs. It may be used.

  Next, another embodiment having a coil configuration different from that of the embodiment of FIG. 1 will be described. In the transformer shown in FIG. 6, the primary coil 16 is divided into two sub-coils 16a and 16b connected in series, and the secondary coil 17 is divided into two sub-coils 17a and 17b connected in series. The transformer shown in FIG. 6 includes a plurality of bobbins 18 and 19 provided to be rotatable with respect to the magnetic core 20. One of the divided subcoils (the subcoil 16a and the subcoil 17a) is wound around one bobbin 18, and the other subcoil (the subcoil 16b and the subcoil 17b) is wound around the other bobbin 19. , 19 are arranged on a pair of linear portions facing each other of a rectangular annular (b-shaped) magnetic core 20.

  In each bobbin, the primary coil (sub-coil) and the secondary coil (sub-coil) are each divided into a plurality of winding portions connected in parallel, and the plurality of winding portions are provided for each of the primary coil and the secondary coil. The configuration alternately arranged in the radial direction of the cylindrical portion is the same as the configuration shown in FIG. The configuration shown in FIG. 6 further increases the number of windings by connecting the secondary coil configured on the bobbin 18 and the secondary coil configured on the bobbin 19 in series for each primary coil and secondary coil. This is the configuration.

  Next, another embodiment in which the configuration of the coil is different from the embodiment of FIG. 1 will be described. In the transformer shown in FIG. 7, the primary coil 21 is divided into two sub-coils 21a and 21b connected in parallel, and the secondary coil 22 is divided into two sub-coils 22a and 22b connected in parallel. The transformer shown in FIG. 7 includes a plurality of bobbins 23 and 24 provided to be rotatable with respect to the magnetic core 25. One of the divided subcoils (the subcoil 21a and the subcoil 22a) is wound around one bobbin 23, and the other subcoil (the subcoil 21b and the subcoil 22b) is wound around the other bobbin 24. , 24 are arranged on two opposing sides of a rectangular core (b-shaped) magnetic core 25, respectively.

  In each bobbin, the primary coil (sub-coil) and the secondary coil (sub-coil) are each divided into a plurality of winding portions connected in parallel, and the plurality of winding portions are provided for each of the primary coil and the secondary coil. The configuration alternately arranged in the radial direction of the cylindrical portion is the same as the configuration shown in FIG. The configuration shown in FIG. 7 further enables the resistance of the coil to be reduced by connecting in parallel the secondary coil configured on the bobbin 23 and the secondary coil configured on the bobbin 24 for each primary coil and secondary coil. It is a configuration.

  The structure which divides | segments a primary coil and a secondary coil into the some subcoil respectively connected in parallel or in series is not limited to the said embodiment. The primary coil and the secondary coil should just contain the part divided | segmented by parallel connection or series connection.

  It is also possible to use a wire with insulation coating such as a three-layer insulated wire as the conductive wire constituting the primary coil and the conductive wire constituting the secondary coil, and to ensure insulation between the primary coil and the secondary coil by such insulation coating. is there. However, when high withstand voltage is required, the volume of the whole winding part will increase if you try to secure insulation between the primary coil and the secondary coil with insulation coating for each conducting wire, so use normal magnet wire (enameled wire) etc. It is preferable to use and arrange a sheet-like insulator between the winding part of the primary coil and the winding part of the secondary coil. By using a sheet-like insulator that has flexibility and strength that can be wound around a bobbin in addition to withstand voltage, it is also possible to wind the sheet-like insulator by utilizing the rotation of the gear portion described above. . As the sheet-like insulator, for example, resin sheets such as polyester, polyimide, and polyphenylene sulfide, and non-woven insulating paper such as aramid fibers (for example, Nomex (Nomex is a registered trademark of DuPont)) are preferable. In consideration of insulation and flexibility, the thickness is preferably 25 to 50 μm for a resin sheet such as polyester, and 50 to 200 μm for a non-woven insulating paper. The number of turns of the sheet-like insulator is not limited to this, but it is preferable to wind two or more times from the viewpoint of insulation and reliability. On the other hand, the number of turns is preferably 10 times or less because the number of steps is increased even if the number of turns is too much.

  Next, a method for manufacturing a transformer according to the embodiment of the present invention will be described. A specific description of the same parts as those described above will be omitted. A first step comprising winding or laminating a magnetic alloy ribbon and attaching a protective member to an uncut magnetic core forming a closed magnetic path (including a form accommodated in a case), and winding a conductive wire A pair of flanges typically provided on both ends of the cylindrical portion so as to sandwich the peripheral surface in the axial direction of the cylindrical portion, and a pair of flange portions, At least one bobbin having at least one gear portion provided at a distance from the flange portion on at least one of the outer sides is rotated around the protective member so that the cylindrical portion covers the protective member. A second step of movably mounting and winding a lead wire on the peripheral surface of the cylindrical portion by rotating the bobbin via the gear portion, whereby a primary coil and a secondary are wound around the cylindrical portion; Coil and shape Including a third step of. The third step includes a step of alternately forming a winding portion of the conducting wire constituting the primary coil and a winding portion of the conducting wire constituting the secondary coil along the radial direction of the cylindrical portion. Yes. In addition, said protection member may be a case which has a linear part and accommodates a magnetic core, and the bobbin may be rotatably attached to the linear part of the case.

  By winding the gear part, winding work is easy even when using an uncut magnetic core, and the winding part of the conducting wire constituting the primary coil and the conducting wire constituting the secondary coil The winding portions can be alternately formed with high accuracy in the radial direction of the cylindrical portion.

  A configuration in which the primary coil and the secondary coil are each divided into a plurality of sub-coils connected in parallel or in series, a configuration related to the notch portion of the flange portion, and a configuration related to the protrusion protruding from the surface of the flange portion The preferred form is as described above. Among these, it supplements about the structure which concerns on protrusion.

  In the third step described above, the rod-shaped protrusions protruding from the surface of the collar portion are used as a restricting structure to restrict the movement of the winding end radially outward when the conductor is wound (when the bobbin is rotated). May be. For example, the winding end pulled out from the notch 10 is drawn around the space on the outer peripheral surface between the flange 8 and the gear 9. At this time, if the winding end is routed so as to be disposed between the cylindrical portion 7 and the rod-shaped protrusion 11, the protrusion 11 functions as a pressing end for the winding end. The winding end can be constrained only by drawing the winding end so as to be disposed between the projection and the cylindrical portion. The winding end may be bound more reliably by binding the winding end to the protrusion for each winding part. For each winding part, the winding end is temporarily restrained by a protrusion, or it is entangled with the protrusion, and after the formation of all the winding parts is completed, the winding ends are connected. The ends are not scattered, and the winding work is facilitated.

  Since the transformer according to the embodiment of the present invention can effectively utilize the characteristics of the magnetic alloy ribbon having a high magnetic flux density while ensuring the workability of the winding, it can be used for various power supply devices. For example, it is suitable for a power supply device such as a switching power supply exceeding 1 kW and an insulating inverter. In particular, the transformer according to the present invention is an electron microscope apparatus having a driving frequency of 10 to 50 kHz and an output of 5 kW or more, for example, a built-in insulating transformer of a power conditioner for alternative energy such as solar power generation, wind power generation, and a power storage unit, and an auxiliary train By using it as an insulation transformer for a power supply device, a step-down transformer for an arc welding machine, etc., it contributes to miniaturization and weight reduction of the insulation transformer and equipment, and improvement of general versatility of the entire system.

  FIG. 8 shows the dependence of the iron loss on the maximum applied magnetic flux density Bm at each frequency of 10 kHz, 20 kHz, and 50 kHz of the cut core and the uncut core of the Fe-based nanocrystalline alloy ribbon that is a magnetic alloy ribbon. The cut core was F3CC6.3 manufactured by Hitachi Metals, Ltd., and a magnetic core was formed by abutting without intentionally forming a gap. The uncut magnetic core was configured using FT-3L material (Bs: 1.23T, Br / Bs: 0.05) manufactured by Hitachi Metals, Ltd. Cut core (F3CC 6.3) and uncut core are each given 3 turns of primary winding and 3 turns of secondary winding, and BH analyzer (SY8232 made by IWASU) via amplifier (4025 made by NF circuit design block) Connected and measured core loss.

  From FIG. 8, when compared at the same Bm and frequency, the core loss of the uncut core is 40% or less of the cut core. This indicates that when the magnetic flux density at which a constant core loss occurs is converted into an allowable operating magnetic flux density, the uncut core can accept an operating magnetic flux density of about 1.6 times that of a cut core using the same core material. .

  Next, when the transformer configured as shown in FIG. 1 is wound around the bobbin 26 with the primary coil 27 and the secondary coil 28 separated in the magnetic path direction as shown in FIG. 9A (coil A). : Comparative example) and a case where the primary coil 31 and the secondary coil 32 are alternately wound around the bobbin 30 in the radial direction as shown in FIG. 9B and configured by coils (coil B: embodiment). Then, the effective resistance (AC resistance) was compared. The magnetic cores 29 and 33 are made of the above-mentioned FT-3L material as a magnetic alloy ribbon, and are configured in a substantially rectangular annular shape having an outer diameter of 80.1 mm × 47.6 mm, an inner diameter of 56.3 mm × 23.8 mm, and a thickness of 12.5 mm. An uncut winding core. Such a magnetic core was accommodated in a case composed of an upper case and a lower case. As the bobbin, a bobbin having a cylindrical portion for winding a conducting wire, a flange portion disposed on both ends of the cylindrical portion, and a gear portion for receiving rotational force outside the flange portion was used. The bobbin was assembled so that the cylindrical part was rotatably supported by the linear part of the case. A bobbin having an inner diameter of 21.2 mm is driven to rotate, a primary coil (Np1) of 0.5φ-32 turns is wound, a polyester sheet having a base material thickness of 25 μm is wound three times as an insulating sheet 34, and then a 0 is placed thereon. A secondary coil (Ns1) of .phi.-32 turns was wound so as to overlap, and an insulating sheet of polyester tape was wound thereon. This operation was repeated three times to form a coil of 0.5φ-3 pieces-32 turns (winding ratio 1: 1). An enlarged view of the coil portion is shown in FIG. Np2 and Ns2 are the primary coil and the second winding part of the secondary coil, respectively, and Np3 and Ns3 are the third winding part of the primary coil and the secondary coil, respectively. A transformer using the magnetic core and the coil was constructed, and the effective resistance (AC resistance) of the coil was measured. The measurement results are shown in FIG.

  In the entire frequency band of 5 kHz or more shown in FIG. 10, the effective resistance of Example 1 using coil B was lower than that of Comparative Example 1 using coil A. In addition, it can be seen that the increase rate of the effective resistance with respect to the increase in the frequency is smaller in the example using the coil B, and particularly the increase rate is suppressed to 100 kHz or less.

  Next, the difference in temperature rise under natural air cooling was examined between the transformer having the configuration shown in FIG. 1 (Example) and a conventional transformer using ferrite (Comparative Example). Regarding the material constituting the magnetic core, the former is the FT-3L material, and the latter is Mn-Zn ferrite. In the embodiment shown in FIG. 1, there is one bobbin, but in this example (Example 2), the bobbin is disposed in each of a pair of opposing linear portions of the rectangular case. The configuration of the magnetic core and the case was the same as that of the transformer shown in FIG. The bobbin is driven to rotate, after winding the primary coil (Np1) of 0.3φ-3 pieces-16 turns, and then winding the insulation sheet of polyester tape on the secondary, 0.3φ-3 pieces-16 turns The coil (Ns1) was wound so as to overlap, and an insulating sheet of polyester tape was wound thereon. This operation was repeated three times to form a coil of 0.3φ-9 pieces-16 turns (winding ratio 1: 1) on one of the pair of linear portions. Further, the same winding was applied to the bobbin attached to the other of the pair of linear portions. The primary and secondary windings of the two bobbins were connected in series as shown in FIG. 6 to form a 3φ-9-32 turns (winding ratio 1: 1) coil.

  On the other hand, in a conventional transformer using ferrite (Comparative Example 2), a magnetic core is configured by abutting EER-shaped ferrite. A bobbin (bobbin for EER53) having an inner peripheral surface shape following the cross-sectional shape of the middle leg of the magnetic core is prepared, and after winding a primary coil (Np1) of 0.55φ-3 pieces-23 turns, a polyester tape An insulating sheet was wound, and a secondary coil (Ns1) of 0.55φ-3 pieces-23 turns was wound thereon, and a polyester tape insulating sheet was wound thereon. This operation was repeated twice to form a coil of 0.55φ-6 wires-23 turns (winding ratio 1: 1).

In the manner described above, a 1: 1 insulating transformer was manufactured according to the standard of switching frequency 20 kHz and input 230 Vrms 9.5 Arms. The volume of the transformer of the example and the transformer of the comparative example were both 183 × 10 ⁻⁶ m ^3, and Bm was designed to be as high as possible without causing problems such as magnetic saturation and burning. Table 1 shows a comparison result between the example and the comparative example. The transformer volume in Table 1 is a volume calculated by the product of the maximum dimensions in three orthogonal directions (x, y, and z directions). Furthermore, the manufactured transformer was mounted on an inverter and a drive comparison was performed. FIG. 11 shows the results of changes in core and coil temperatures with respect to driving time.

  Although the transformer of the example exceeded 0.7T and was driven at a magnetic flux density nearly four times that of the transformer of the comparative example, the core loss was almost the same, and as shown in FIG. There was no significant difference from the transformer of the comparative example. That is, it was confirmed that the transformer of the example can be driven with a high magnetic flux density.

  Further, the temperature of the coil surface was significantly lower in the transformer of the example than in the transformer of the comparative example, and it was confirmed that the structure of the transformer of the example was excellent in heat dissipation.

  Furthermore, as shown in Table 1, the volume of the magnetic core of the transformer of the example and the mass of the entire transformer were 1/3 or less and 2/3 or less of the comparative example, respectively. That is, it has been found that the transformer can be significantly reduced in weight by adopting the configuration of the transformer according to the embodiment of the present invention. In addition, since the temperature rise of the coil is significantly suppressed in the example, if the coil temperature rise is designed to be equivalent to that of the comparative example, the configuration according to the example can be downsized. I know that there is.

  Next, 10 kHz, 20 kW (200 V) when the uncut magnetic core wound with the magnetic alloy ribbon (FT-3L material) is used (Example 3) and when the ferrite magnetic core is used (Comparative Example 3). 100 Arms) and a winding ratio of 1: 1, and the transformer volume was designed to be minimum under the condition that the temperature rise in natural air cooling was 45 ° C. In the transformer according to this example, the arrangement of the magnetic core and the coil was the same as that of the transformer of Example 2 described above.

  Moreover, the transformer according to the comparative example is a UU core with long legs abutted in the coil foam, the magnetic core is a UU-shaped Mn-Zn ferrite having a rectangular cross section, the coil foam is a primary coil on a rectangular bobbin, Secondary coils were alternately wound. Table 2 shows a comparison result of the transformer according to the example and the transformer according to the comparative example.

  In the transformer of the example that can be driven with a high magnetic flux density, a reduction in size and weight of 19% in volume and 39% in mass are realized compared to the transformer in the comparative example, and a remarkable effect is obtained. I understand.

  Next, when using an uncut magnetic core wound with a magnetic alloy ribbon (FT-3L material) (Example 4) and when using a Fe-based nanocrystalline alloy ribbon core (Comparative Example 4) Thus, the transformer was designed to have a minimum volume under the condition of 50 kHz, 5 kW (200 V, 25 Arms) and a turns ratio of 1: 1, and a temperature rise in natural air cooling was 45 ° C. In the transformer according to this example, the arrangement of the magnetic core and the coil was the same as that of the transformer of Example 2 described above.

  Moreover, the transformer according to the comparative example is a UU core with long legs butted in a coil form, and the magnetic core is FT-3M material (Bs: 1.23T, Br / Bs: 0.5 manufactured by Hitachi Metals, Ltd.). ) And a coil form in which a primary coil and a secondary coil are alternately wound around a rectangular bobbin. Table 3 shows a comparison result of the transformer according to the example and the transformer according to the comparative example.

  In the transformer of the example that can be driven with a high magnetic flux density, a reduction in size and weight of 18% in volume and 49% in mass are realized compared to the transformer in the comparative example, and a remarkable effect is obtained. I understand.

  The transformer according to the embodiment of the present invention is suitably used in, for example, a switching power supply or an insulated inverter having a driving frequency of 10 kHz or more and an output of 5 kW or more.

100: Transformer
1: Case
2, 12, 16, 21, 27, 31: Primary coil
3, 13, 17, 22, 28, 32: secondary coil
4, 14, 18, 19, 23, 24, 26, 30: Bobbin 5, 15, 20, 25, 29, 33: Magnetic core
6: Straight section
7: Cylindrical part
8: Buttocks
9: Gear section
10: Notch 11: Protrusion 34: Sheet-like insulator

Claims (16)

An uncut magnetic core formed by winding or laminating a magnetic alloy ribbon and forming a closed magnetic path;
A protective member covering at least a part of the magnetic core;
A primary coil and a secondary coil;
And at least one bobbin provided for winding a conducting wire constituting the primary coil and the secondary coil,
The at least one bobbin includes a cylindrical portion having a peripheral surface around which the conducting wire is wound, a pair of flange portions provided so as to sandwich the peripheral surface in the axial direction of the cylindrical portion, and the pair of flange portions And at least one gear portion provided at a distance from the flange portion on the outside of at least one of them, and is supported rotatably around the protection member in the cylindrical portion,
At least one of the pair of flanges has an outer peripheral edge of the flange as a conductor passage part for arranging an end of the conductor wound around the circumferential surface of the cylindrical part outside the flange. A pair of notch portions that allow the conducting wire to pass therethrough at a position radially inward of the pair, and the pair of notch portions are paired so as to sandwich the cylindrical portion when viewed in the axial direction of the cylindrical portion. Is arranged,
The winding part of the conducting wire which comprises the said primary coil, and the winding part of the conducting wire which comprises the said secondary coil are alternately arrange | positioned in the radial direction of the said cylindrical part, and the winding part of the conducting wire which comprises the said secondary coil Each of the windings of the plurality of winding portions of the conducting wire constituting the primary coil that are stacked via each other is connected in parallel outside the flange, and the winding of the conducting wire constituting the primary coil Each of the conductors of the plurality of winding portions of the conductor wire that constitutes the secondary coil stacked via a portion is connected in parallel outside the flange portion,
An end portion of the conducting wire constituting the primary coil is arranged on the outer side of the flange portion through one notch portion of the pair of notch portions, and an end of the conducting wire constituting the secondary coil The part is disposed on the outer side of the flange part through the other notch part of the pair of notch parts.   The at least one bobbin includes a plurality of bobbin members combined so as to sandwich the protection member around the protection member, and each of the plurality of bobbin members includes a part of the cylindrical portion. Item 4. The transformer according to Item 1. The at least one bobbin includes a plurality of bobbins;
The transformer according to claim 1 or 2, wherein the primary coil and the secondary coil are each divided into a plurality of subcoils connected in parallel or in series and arranged on the plurality of bobbins.   The magnetic alloy ribbon has a magnetic property that a saturation magnetic flux density Bs is 1.0 T or more and a ratio Br / Bs of a residual magnetic flux density Br to the saturation magnetic flux density Bs is 0.3 or less. 4. The transformer according to any one of 3 to 3.   The transformer according to any one of claims 1 to 4, wherein a sheet-like insulator is disposed between a winding portion of the primary coil and a winding portion of the secondary coil.   In the at least one bobbin, when the bobbin is rotated, an end portion of the conducting wire arranged outside the flange through the conducting wire passage portion moves toward a radially outer side of the cylindrical portion. The transformer according to any one of claims 1 to 5, further comprising a restricting portion having a surface that prevents this.   The transformer according to any one of claims 1 to 6, further comprising a rod-shaped protrusion that protrudes from the surface of the flange toward the outside in the axial direction of the cylindrical portion.   The transformer according to claim 1, wherein the protective member is a case that accommodates the magnetic core.   The at least one bobbin has an outer peripheral surface between the flange portion and the gear portion, and the diameter of the outer peripheral surface and the diameter of the peripheral surface of the cylindrical portion are the same. 9. The transformer according to any one of 8.   A power supply device comprising the transformer according to claim 1.   The power supply device according to claim 10, which is an insulated inverter or an insulated switching power supply having a driving frequency of 10 to 50 kHz and an output of 5 kW or more. A first step of mounting a protective member on an uncut magnetic core formed by winding or laminating a magnetic alloy ribbon and forming a closed magnetic path;
A cylindrical portion having a circumferential surface around which a conducting wire is wound, a pair of flange portions provided so as to sandwich the circumferential surface in the axial direction of the cylindrical portion, and at least one outer side of the pair of flange portions A second step of attaching at least one bobbin having at least one gear portion provided at a distance from the flange portion to be rotatable around the protective member in the cylindrical portion;
A conductive wire is wound on the circumferential surface of the cylindrical portion by rotating the at least one bobbin via the gear portion, thereby forming a primary coil and a secondary coil around the cylindrical portion. Including the steps of
In at least one bobbin rotatably attached around the protective member, at least one of the pair of flanges is paired so as to sandwich the cylindrical part when viewed from the axial direction of the cylindrical part. A pair of cutouts arranged without being formed,
The third step includes a step of alternately forming a winding portion of the conducting wire constituting the primary coil and a winding portion of the conducting wire constituting the secondary coil in the radial direction of the cylindrical portion, In the step of alternately forming the winding portions, the conductive wires are arranged in a state in which the end portions of the conductive wires constituting the primary coil are arranged outside one of the pair of cutout portions from outside the flange portion. wound and then wound the wire in the state in which the end portion of the lead constituting the secondary coil arranged on the outside of the flange portion from the other notch of the pair of cutout portions,
After the third step, by connecting end portions of a plurality of conducting wires arranged outside the flange portion from the one notch portion, a plurality of winding portions of the conducting wire constituting the primary coil are connected. By connecting each of the conductive wires in parallel outside the flange and connecting the ends of a plurality of conductive wires arranged outside the flange from the other notch, the secondary coil is fourth step further encompasses a method of manufacturing the transformer connecting each conductor of plurality of windings of conductive wire constituting the parallel outside of the flange portion. The at least one bobbin includes a plurality of bobbins;
The method of manufacturing a transformer according to claim 12, wherein the primary coil and the secondary coil are each divided into a plurality of sub-coils connected in parallel or in series and arranged on the plurality of bobbins.   The transformer according to claim 12 or 13, wherein, in the third step, when the winding portion of the conducting wire is formed, an end portion of the conducting wire is disposed in a gap between the flange portion and the gear portion. Manufacturing method. The at least one bobbin further includes a restricting portion having a surface that prevents the end portion of the conducting wire disposed outside the flange portion from moving toward the radially outer side of the cylindrical portion,
The said 3rd process WHEREIN: When forming the winding part of the said conducting wire, the edge part of the said conducting wire is distribute | arranged to the position inside the said control part in the radial direction of the said cylindrical part. Manufacturing method of transformer. The at least one bobbin has a rod-like protrusion that protrudes from the surface of the flange toward the outside in the axial direction of the cylindrical part,
The method of manufacturing a transformer according to claim 12, wherein the third step includes a step of binding an end portion of the conducting wire to the protrusion.

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