WO2011136144A1

WO2011136144A1 - Bobbin for electrical equipment and method for producing same

Info

Publication number: WO2011136144A1
Application number: PCT/JP2011/059937
Authority: WO
Inventors: 英之森下; 有仁野々村; 三好與倉; 正人深萱; 武司神保
Original assignee: 河村産業株式会社
Priority date: 2010-04-28
Filing date: 2011-04-22
Publication date: 2011-11-03
Also published as: TW201218580A; KR20120117918A

Abstract

Disclosed is a bobbin for electrical equipment, provided with a body portion, jaw portions, and engagement holes. The body portion is composed of an insulation film, and has a cylindrical shape. The jaw portions are respectively provided on both axial ends of the body portion, and the body portion is fitted in the inner peripheral portions of the jaw portions. The jaw portions are composed of a material different from the material of the body portion, and are annularly projected from the body portion toward the outside in the radial direction. The engagement holes are respectively provided on both axial ends of the body portion, and penetrate through the body portion in the thickness direction. The inner peripheral-side portion of each jaw portion, which is opposite to the body portion, is inserted in each engagement hole.

Description

Bobbin for electrical equipment and manufacturing method thereof

The present invention relates to a bobbin for an electric device used for an electric device such as an electric motor, a generator, a transformer, and an inverter, and a manufacturing method thereof.

In general, bobbins for electrical equipment used for electric motors, generators, transformers, inverters, etc. are provided on each of a cylindrical body having a round shape or a square shape, and both axial ends of the body. Department. The trunk portion and the collar portion are usually made of synthetic resin, and are integrally formed by injection molding as shown in Patent Document 1, for example. In such a bobbin for an electric device in which the body part and the collar part are integrally formed by injection molding, the thickness of the body part is usually as thick as 2 to 3 mm. It is.

For example, Patent Document 2 discloses a configuration in which the body portion is thinned. The body part of the bobbin for electric equipment disclosed in Patent Document 2 is composed of a first holding member made of synthetic resin and a second holding member of a thin film body which is a nonmagnetic material.

However, when the body is composed of two members, the first holding member and the second holding member, it is necessary to ensure the bonding strength between the two members. If the joining of these two members is insufficient, the first holding member is likely to be detached from the second holding member when an electric wire is wound around the body portion or when a bobbin for an electric device is mounted on the stator core. There's a problem. Further, since the thick first holding member forms a part of the body portion, there is a problem that it is difficult to improve the line area ratio and the thermal conductivity.

JP 2008-167598 A JP 2009-213311 A

Therefore, an object of the present invention is to provide a bobbin for an electric device having a high line area ratio of electric wires, excellent heat dissipation, and high joint strength of members, and a manufacturing method thereof.

In order to achieve the above-described object, the bobbin for an electric device according to the present invention includes a body portion, a flange portion, and an engagement hole. The trunk | drum is formed in the cylinder shape with the insulating film. The flanges are provided at both end portions in the axial direction of the body part, the body parts are fitted on the inner peripheral side, are formed of a material different from that of the body part, and project annularly from the body part radially outward. The engagement holes are respectively provided at both end portions in the axial direction of the body portion, penetrate the body portion in the thickness direction, and the inner peripheral side of the collar portion facing the body portion enters.

Further, the method for manufacturing a bobbin for an electric device according to the present invention includes a step of forming a body portion and a step of forming a collar portion. In the step of forming the body portion, an insulating material having a thickness of 0.05 mm to 0.5 mm is formed into a cylindrical body portion. In the step of forming the collar portion, it is formed at both end portions in the axial direction of the barrel portion molded into a cylindrical shape with an outer diameter larger than that of the barrel portion. At this time, the collar portion is formed integrally with the trunk portion.

According to the bobbin for electric equipment of the present invention, the body and the buttock are formed of different materials. Moreover, the trunk | drum is formed with the insulating film. Therefore, it is easy to reduce the thickness of the trunk portion. Therefore, the number of turns of the electric wire per unit cross-sectional area, that is, the line area ratio of the electric wire can be increased. Further, the heat generated in the electric wire is transmitted to, for example, a stator core through an insulating film having a small thickness. Therefore, the heat dissipation of an electric wire can be improved. Furthermore, the collar part has entered the engagement hole of the trunk part. Therefore, the collar part and the trunk part are in a state of being engaged with each other in the engagement hole. Therefore, the joint strength between the trunk part and the collar part can be increased, and the dropping of the collar part from the trunk part can be reduced.

According to the method for manufacturing a bobbin for an electric device of the present invention, it is possible to manufacture an electric device bobbin having a high wire area ratio, excellent heat dissipation, and high bonding strength.

Sectional drawing which shows the state which fitted the bobbin for electrical devices by 1st Embodiment to the stator core The schematic which looked at the state which fitted the bobbin for electric devices by 1st Embodiment to the stator core from the center side of the stator core Sectional view along line III-III in Fig. 1 Sectional view along line IV-IV in FIG. Sectional drawing which expands and shows the principal part of the bobbin for electric devices by 1st Embodiment shown in FIG. The figure equivalent to FIG. 1 which shows the state before fitting the bobbin for electrical devices by 1st Embodiment to a stator core. The schematic perspective view which shows the bobbin for electric devices by 1st Embodiment. The side view which looked at the bobbin for electric devices by 1st Embodiment from the right side of FIG. The top view which looked at the bobbin for electric devices by 1st Embodiment from the upper direction of FIG. Sectional view along line XX in FIG. Sectional view along line XI-XI in FIG. Schematic which shows the manufacturing process of the bobbin for electrical devices by 1st Embodiment. Schematic diagram showing a low-temperature plasma treatment machine (A) is sectional drawing which shows the outline of the bobbin for electric devices of 1st Embodiment, (b) is sectional drawing which shows the outline of the conventional bobbin for electric devices. The figure equivalent to FIG. 5 which shows the bobbin for electric devices by 2nd Embodiment. The figure equivalent to FIG. 11 which shows the bobbin for electric devices by 3rd Embodiment. Sectional view along line XVII-XVII in FIG. The figure equivalent to FIG. 16 which shows the bobbin for electric devices by 4th Embodiment. Sectional view along line XIX-XIX in FIG. Schematic which shows the manufacturing process of the bobbin for electric devices by 5th Embodiment The top view which expand | deployed the trunk | drum of the bobbin for electric devices by 6th Embodiment The figure equivalent to FIG. 21 which shows the bobbin for electric devices by 7th Embodiment. The figure equivalent to FIG. 21 which shows the bobbin for electric devices by 8th Embodiment. The figure corresponding to FIG. 5 which shows the bobbin for electric devices by 9th Embodiment. Schematic which shows the bobbin for electric devices by 10th Embodiment.

Hereinafter, a plurality of embodiments of an electric equipment bobbin will be described with reference to the drawings. Note that, in a plurality of embodiments, the same components are denoted by the same reference numerals, and description thereof is omitted.
(First embodiment)
First, a first embodiment will be described with reference to FIGS. In the drawings, the front, rear, left and right and up and down directions are indicated by arrows. In the present specification, for the sake of convenience, the axial direction of the rotating electrical machine will be described as the vertical direction.

The bobbin for electric equipment according to the first embodiment is applied to a rotating electric machine used as a motor and a generator in a hybrid vehicle or an electric vehicle. The bobbin for electrical equipment is not limited to the rotating electrical machine of this vehicle, but may be applied to other electrical equipment such as a transformer or an inverter.
1 to 4 show a part of the inner rotor type rotating electrical machine 11 in an enlarged manner. The rotating electrical machine 11 includes a stator 12 and a rotor 13 as shown in FIG. The rotor 13 is provided on the inner peripheral side of the stator 12 with a predetermined gap therebetween. The rotor 13 has a rotor core 14 and a permanent magnet (not shown). The permanent magnet is embedded in the rotor core 14. The rotor core 14 is formed in a cylindrical shape, and a shaft (not shown) is provided on the inner peripheral side.

The stator 12 has a stator core 15 and a coil 16. The stator core 15 has a yoke portion 17 and a plurality of teeth portions 18. The yoke portion 17 is formed in a cylindrical shape. The teeth part 18 protrudes from the inner peripheral end of the yoke part 17 toward the central axis. FIG. 1 shows only one tooth portion 18 among the plurality of tooth portions 18. The yoke portion 17 may employ various shapes of outer walls such as an ellipse and a polygon instead of a complete cylindrical outer wall. The teeth portion 18 is formed in a substantially rectangular parallelepiped shape as shown in FIGS. The teeth 18 are arranged at equal intervals in the circumferential direction of the stator core 15. As a result, a slot 15a is formed between the adjacent tooth portions 18 in the stator core 15 as shown in FIGS.

The coil 16 is formed by winding an electric wire such as a copper wire around the outer peripheral side of the body portion 22 of the bobbin 21 for electrical equipment. In the case of the first embodiment, as shown in FIG. 6, the electric equipment bobbin 21 provided with the coil 16 is fitted into the tooth portion 18 from the inner peripheral side of the stator core 15. As a result, the coil 16 around which the electric wire is wound is provided on the tooth portion 18 with the body portion 22 of the bobbin 21 for electric equipment interposed therebetween. An arrow F shown in FIG. 6 is a direction in which the electric equipment bobbin 21 is fitted.

The electrical equipment bobbin 21 has a body part 22, a first flange part 23, a second flange part 24, and an engaged part 25 as shown in FIGS. The trunk | drum 22 is formed in the cylinder shape. In the case of the first embodiment, the body portion 22 is formed in a rectangular tube shape. The trunk portion 22 is not limited to a rectangular tube shape, and can be arbitrarily set according to the shape of the tooth portion 18 such as a cylindrical shape or an elliptical cylindrical shape. As shown in FIGS. 7 to 11, the body 22 has an upper side wall 22a, a lower side wall 22b, a right side wall 22c, and a left side wall 22d. The upper side wall 22a, the lower side wall 22b, the right side wall 22c, and the left side wall 22d form a space 21a inside. The space 21 a substantially matches the shape of the tooth portion 18 and is set slightly larger than the tooth portion 18. The upper side wall 22a and the lower side wall 22b are positioned at axial ends of the stator core 15 when the electric equipment bobbin 21 is fitted to the tooth portion 18 as shown in FIGS. Further, the right side wall 22 c and the left side wall 22 d are located in the slot 15 a of the stator core 15 when the electric equipment bobbin 21 is fitted to the tooth portion 18.

Here, the body 22 including the upper side wall 22a, the lower side wall 22b, the right side wall 22c, and the left side wall 22d is formed of an insulating material such as an insulating film. This insulating film is a film having a known insulating property such as a film made of a general-purpose insulating material or a film made of a laminated insulating material. Examples of the insulating film include plastic films such as aramid paper such as Nomex (registered trademark) manufactured by Du Pont of the United States, polyphenylene sulfide film, polyimide film, polyether ether ketone film, and polyethylene terephthalate film. In particular, a laminated film obtained by laminating aramid paper and a plastic film is excellent in heat resistance, insulation, mechanical properties, and the like. Therefore, a laminated film obtained by laminating aramid paper and a plastic film can be suitably used as an insulating film that forms the body portion 22 of the bobbin 21 for an electric device. In particular, a laminated film in which an aramid paper and a polyphenylene sulfide film are laminated, and a laminated film in which an aramid paper and a polyimide film are laminated are more preferable as an insulating film for forming the body portion 22 of the bobbin 21 for an electric device. Further, as shown in FIG. 14 (a), the thickness _{T 1} of the insulating film forming the body portion 22 is set to 0.05 ~ 0.5 mm. The thickness _{T 1} of the insulating film forming the body portion 22 is preferably 0.1 ~ 0.4 mm, more preferably 0.2 ~ 0.3 mm. The thickness _{T 1} of the insulating film forming the body portion 22, the strength is insufficient with less than 0.05 mm. For this reason, when an electric wire is wound around the bobbin 21 for an electric device, problems such as deformation of the body portion 22 are likely to occur. On the other hand, the thickness _{T 1} of the insulating film forming the body portion 22 exceeds 0.5 mm, the thickness of the body portion 22 becomes excessive. Therefore, since the number of turns of the electric wire is reduced, the line area ratio is lowered, and the heat dissipation is also lowered due to the decrease in thermal conductivity. The body portion 22 is integrally connected to the first flange portion 23 and the second flange portion 24.

The electrical equipment bobbin 21 includes a plurality of engagement holes 22e. Specifically, the engagement holes 22e are provided at both end portions in the axial direction of the body portion 22, respectively. As shown in FIGS. 5 and 7, the engagement hole 22 e penetrates the insulating film forming the body portion 22 in the thickness direction, that is, in the radial direction. The engagement hole 22e has a circular cross-sectional shape, for example.

The surface of the insulating film forming the barrel 22 is subjected to surface treatment. Specifically, the surface of the insulating film forming the body is subjected to, for example, plasma treatment, corona treatment, chemical treatment, or the like. These processes may be only one type or a combination of a plurality of processes. By subjecting the insulating film forming the body portion 22 to surface treatment, the surface of the insulating film is modified in properties such as hydrophilicity. Therefore, for example, the adhesion of the surface of the insulating film is improved as the wettability is improved. As a result, the body portion 22 forming the insulating film, the first flange portion 23, and the second flange portion 24 are more firmly bonded. As the surface treatment, plasma treatment is particularly preferable in order to enhance effects such as ease of treatment and wettability. In this specification, plasma processing will be described as an example.

The 1st collar part 23 and the 2nd collar part 24 regulate the movement of the coil 16 provided in the trunk | drum 22. Specifically, the coil 16 provided in the trunk portion 22 is displaced in the radial direction of the stator core 15. Therefore, the first flange portion 23 and the second flange portion 24 are in contact with the coil 16 at the end portion in the axial direction of the body portion 22 and restrict the movement of the coil 16.

Both the first collar part 23 and the second collar part 24 are formed in an annular shape that protrudes radially outward from the body part 22. That is, as for the 1st collar part 23, the edge part of the inner peripheral side has opposed the trunk | drum 22. The first flange portion 23 is provided at one end portion in the axial direction of the trunk portion 22. Specifically, the first flange portion 23 is located on the side of the stator core 15 that faces the yoke portion 17 when the electric equipment bobbin 21 is fitted to the tooth portion 18. The first flange 23 has a plurality of engaged portions 25 on the inner peripheral side. The engaged portion 25 enters the engagement hole 22e formed by the body portion 22 when the first flange portion 23 is attached to the body portion 22. The engaged portion 25 is formed in a columnar shape corresponding to the engaging hole 22e. The engaged portion 25 can be changed in shape according to the shape of the engagement hole 22e. For example, when the cross section of the engagement hole 22e is a square shape, the engaged portion 25 is formed in a quadrangular prism shape.

The second collar part 24 has an inner peripheral edge facing the body part 22 in the same manner as the first collar part 23. The second flange 24 is provided at the other end in the axial direction of the body 22, that is, at the end opposite to the first flange 23. Specifically, the second flange portion 24 is located on the center side of the stator core 15 when the electric device bobbin 21 is fitted to the tooth portion 18. The second flange portion 24 is set so that the total length in the circumferential direction of the stator core 15 is smaller than that of the first flange portion 23. This is because the second flange portion 24 is located closer to the center side of the stator core 15 than the first flange portion 23. That is, the electric equipment bobbin 21 is fitted to the teeth portion 18 formed radially with respect to the center of the stator core 15. Therefore, the interval between the bobbins 21 for electric equipment adjacent in the circumferential direction of the stator core 15 is smaller toward the center side of the stator core 15, that is, the second flange portion 24 side. Thereby, the second collar part 24 is set to have a smaller overall length in the circumferential direction of the stator core 15 than the first collar part 23 so that the second collar parts 24 of the adjacent bobbins 21 for electrical equipment do not contact each other. Yes. Similar to the first collar part 23, the second collar part 24 has a plurality of engaged parts 25 on the inner peripheral side. The engaged portion 25 enters the engagement hole 22 e formed by the body portion 22 when the second flange portion 24 is attached to the body portion 22. The shape of the engaged portion 25 of the second flange 24 is the same as that of the first flange 23.

The surface of the second flange portion 24 on the rotor 13 side may be curved concentrically with the outer wall of the rotor 13. Further, the surface of the first flange portion 23 on the side of the yoke portion 17 may be curved concentrically with the inner wall of the yoke portion 17. In particular, since the surface of the first flange portion 23 on the side of the yoke portion 17 and the inner wall of the yoke portion 17 have an approximate curvature, the end portion on the yoke portion 17 side of the bobbin 21 for electric equipment is formed by the inner wall of the yoke portion 17. The position is determined.

The 1st collar part 23, the 2nd collar part 24, and the to-be-engaged part 25 are formed with the synthetic resin. Here, as the synthetic resin, for example, polyphenylene sulfide resin (PPS resin), acrylonitrile-butadiene-styrene copolymer resin, polyimide resin, polyethylene terephthalate resin, polyacetal resin, and the like are preferable. The first flange portion 23, the second flange portion 24, and the engaged portion 25 are formed integrally with the body portion 22 by, for example, insert molding. The thickness of the 1st collar part 23 and the 2nd collar part 24 is arbitrary. In the first embodiment, the first flange portion 23 and the second flange portion 24 is set the the _second thickness T ₂ as shown in FIG. 14 to 2 ~ 3 mm. The thickness T ₂ of the first flange portion 23 and the second flange portion 24 is preferably set as small as possible within a range capable of forming. By thus reducing the thickness T ₂ of the first flange portion 23 and the second flange portion 24, body portion 22 of the electric device for the bobbin 21 is the total length in the axial direction is enlarged. As a result, the number of turns of the electric wire wound around the trunk portion 22 increases, and the line area ratio of the electric wire is increased.

The engaged portion 25 is filled in the engagement hole 22e of the body portion 22 simultaneously with the formation of the first flange portion 23 and the second flange portion 24. Thereby, the engaged portion 25 is formed integrally with the first flange portion 23 and the second flange portion 24, respectively. In this way, the engaged portions of the first flange portion 23 and the second flange portion 24 are filled by filling the engaged portion 25 into the engagement hole 22e simultaneously with the formation of the first flange portion 23 and the second flange portion 24. 25 enters the engagement hole 22e and is engaged. As a result, the first flange portion 23 and the second flange portion 24 and the body portion 22 can be firmly connected.

The electrical equipment bobbin 21 includes a filling member 26 as shown in FIG. The filling member 26 is formed between the body portion 22, the first flange portion 23, and the second flange portion 24 on the inner peripheral side of the barrel portion 22, the inner periphery side of the first flange portion 23, and the inner periphery side of the second flange portion 24. Fill the gap between them. The filling member 26 is desirably formed of a material having excellent thermal conductivity. The filling member 26 is desirably a material whose fluidity increases as the temperature rises, such as a thermoplastic resin or grease.

Next, an insert molding die used for molding the bobbin 21 for electric equipment will be described with reference to FIG.
An insert molding die 31 shown in FIG. 12 includes a base portion 32, a lower die 33, and an upper die 34. The lower mold 33 is provided above the base portion 32. The upper mold 34 is provided above the lower mold 33. The base portion 32 holds the lower die 33 and the upper die 34. The base part 32 has a block part 35 for determining the position of the body part 22 of the bobbin 21 for electric equipment. The block portion 35 has a quadrangular prism shape that is substantially the same shape as the tooth portion 18 of the stator core 15. The base portion 32 has a plurality of protruding pins 36 that protrude upward. The protruding pin 36 is for removing the bobbin 21 for electric equipment formed from the lower mold 33.

The lower mold 33 is composed of a pair of block-shaped movable lower molds 37. The pair of movable lower molds 37 is provided above the base part 32 and moves along the upper surface of the base part 32 to open the mold. An arrow Y shown in FIG. 12 indicates the direction in which the mold opens. The movable lower die 37 has a notch 38 ′ corresponding to the shape of almost half of the electric equipment bobbin 21. The pair of movable lower dies 37 are combined to form a cavity 38 that houses the bobbin 21 for an electric device. A nozzle 39 that connects the movable lower mold 37 and the cavity 38 is provided above the movable lower mold 37. The nozzle 39 supplies, for example, molten resin such as PPS to the cavity 38. The first brim part 23 and the second brim part 24 are formed by the resin supplied from the nozzle 39.

The upper die 34 has a spool runner 40 penetrating vertically. The molten resin is supplied to the nozzle 39 of the lower mold 33 via the spool runner 40 of the upper mold 34. A storage portion 41 connected to the spool runner 40 is formed at the upper end of the upper die 34. The molten resin supplied from the outside is stored in the storage unit 41. By combining the upper mold 34 and the lower mold 33, the lower end portion of the spool runner 40 is connected to the nozzle 39.

Next, plasma processing will be described with reference to FIG.
The plasma treatment is performed using a discharge generated by applying a direct current or alternating current high voltage between the electrodes. The discharge generated by the application of a high voltage is a corona discharge at atmospheric pressure or a glow discharge in vacuum. The insulating film forming the body portion 22 is subjected to plasma treatment by being exposed to the electric discharge generated thereby. The plasma treatment is preferably a vacuum treatment with a wide selection range of treatment gases. In the plasma treatment, helium, neon, argon, nitrogen, oxygen, carbon dioxide gas, air, water vapor, or the like is used alone or in a mixed state as a treatment gas. Of these, argon and carbon dioxide are preferable from the viewpoint of discharge starting efficiency. The treatment pressure in the plasma treatment is in a pressure range of 0.1 Pa to 1330 Pa, and more preferably in a range of 1 Pa to 266 Pa.

13 has a process chamber 52 that can be sealed. The processing chamber 52 accommodates a processing roller 53 therein. The electrode 54 surrounds the processing roller 53 by forming a slight gap. The processing roller 53 is grounded. The electrode 54 is connected to a high frequency power supply 55. The processing chamber 52 is decompressed by opening a valve 56 connected to a vacuum pump (not shown). At the same time, the processing chamber 52 is supplied with processing gas by opening a valve 57 connected to a gas supply source (not shown). The processing chamber 52 is provided with a pressure gauge 58 for detecting the internal pressure.

The insulating film 42 wound in a roll shape is drawn out from the supply unit 59. The drawn insulating film 42 is wound around the processing roller 53 while being guided by a plurality of guide rollers 60 in the processing chamber 52. At this time, the insulating film 42 passes through the processing portion between the insulating film 42 and the plasma processing. The insulating film 42 that has been subjected to the plasma treatment is wound around the winding portion 61 while being guided by the guide roller 60. At this time, the insulating film 42 is subjected to plasma treatment on one side or both sides. When plasma processing is performed on one surface of the insulating film 42, the surface subjected to the plasma processing is disposed on the outer peripheral side of the body portion 22.

Next, the manufacturing procedure of the bobbin 21 for electrical equipment will be described with reference to FIG.
The insulating film 42 constituting the body portion 22 is subjected to a surface treatment process. The surface treatment process is, for example, plasma treatment using the above-described plasma treatment machine 51. As shown in FIG. 12A, the plasma-treated film-like insulating film 42 is cut into a shape in which the body portion 22 is developed, that is, a rectangular shape. The length P of the long side of the insulating film 42 after cutting is the length in the horizontal direction of the upper side wall 22a, the length in the vertical direction of the left side wall 22d, the length in the horizontal direction of the lower side wall 22b, and the vertical length of the right side wall 22c. This corresponds to the length of the direction plus the glue margin as necessary. Further, the length Q of the short side after cutting corresponds to the length in the front-rear direction of the body portion 22 and the length in the front-rear direction of the upper side wall 22a. Here, the thickness of the insulating film 42 is set to 0.05 to 0.5 mm.

The insulating film 42 is formed with holes corresponding to the engagement holes 22e at both ends of the long side when the body 22 is formed into a developed shape or before and after the forming. The engaging hole 22e may be formed after the insulating film 42 is formed into a predetermined shape, or the insulating film 42 may be formed after the engaging hole 22e is formed in advance. Further, the insulating film 42 and the engagement hole 22e may be formed simultaneously by a punching press using a mold.

The formed insulating film 42 is formed into a shape corresponding to the body 22 as shown in FIG. In the first embodiment, the insulating film 42 is formed in a rectangular tube shape. When the insulating film 42 includes an adhesive margin, the insulating film 42 bent into a rectangular tube shape has an adhesive margin portion located on the upper side wall 22a or the lower side wall 22b. Further, when the body portion 22 is molded, an adhesive or the like may be applied to the glue margin, and the insulating film 42 may be temporarily fixed before insert molding. As a result, the molded insulating film 42 is less likely to lose its shape during insert molding. The process of forming the insulating film 42, forming the engagement hole 22e, and forming the body shape corresponds to a body shaping process.

As shown in FIGS. 12 (c) and 12 (d), the insulating film 42 formed into a cylindrical shape is blocked in a state where the lower mold 33 is opened, that is, the movable lower mold 37 is separated from each other. It is inserted into the part 35. The process of fitting the insulating film 42 into the block part 35 of the lower mold 33 corresponds to a trunk part arranging step. The insulating film 42 formed into a cylindrical shape is slightly separated from the base portion 32 when fitted into the block portion 35. By disposing the insulating film 42 thus formed and the base portion 32 apart from each other, the resin at the time of insert molding is injected outside the end portion in the axial direction of the body portion 22. As a result, the strength of the end portion in the axial direction of the body portion 22 is increased. When the insulating film 42 formed into a cylindrical shape is disposed on the block portion 35, the movable lower mold 37 is combined to form a cavity 38 as shown in FIG. Thereby, the cylindrical insulating film 42 is accommodated in the cavity 38. This process corresponds to a lower mold fixing process.

When the insulating film 42 formed into a cylindrical shape is accommodated in the cavity 38, the upper die 34 is attached to the upper surface of the lower die 33 as shown in FIG. Then, the molten resin is injected into the storage portion 41 of the upper mold 34. The resin injected into the storage unit 41 is supplied to the cavity 38 via the spool runner 40 and the nozzle 39. As a result, insert molding is performed using the insulating film 42 formed into a cylindrical shape, that is, the barrel portion 22 as an insert, and the barrel portion 22 is integrated with the first flange portion 23, the second flange portion 24, and the engaged portion 25. To be molded. That is, by injecting molten resin, the first flange portion 23, the second flange portion 24, and the engaged portion 25 are formed integrally with the barrel portion 22 using the barrel portion 22 as an insert. This process corresponds to a buttocks molding process. By this insert molding, the engaged portion 25 formed by resin injection enters the engaging hole 22e of the body portion 22. Therefore, the engaged portion 25 integrally protruding from the first flange portion 23 and the second flange portion 24 is in a state of being engaged with the engagement hole 22e.

The surface of the body portion 22 is improved in wettability and adhesiveness by applying a surface treatment such as plasma treatment to the insulating film in advance. Therefore, the molten resin forming the first flange portion 23 and the second flange portion 24 is ensured to have fluidity along the insulating film 42. As a result, the resin forming the first flange portion 23 and the second flange portion 24 adheres to the body portion 22 in a sufficient range. Thereby, the trunk | drum 22 and a collar part fully join, and the crack of the 1st collar part 23 and the 2nd collar part 24 after a shaping | molding, etc. are reduced.

After the buttocks forming process by insert molding, the upper die 34 is removed from the lower die 33. The movable lower mold 37 of the lower mold 33 opens the mold. At this time, the protruding pin 36 of the base portion 32 protrudes from the base portion 32, whereby the electric equipment bobbin 21 is removed from the base portion 32.

In the above description of the manufacturing process, the example in which the surface treatment process such as the plasma treatment is performed before the trunk shaping process is described, but after the trunk shaping process is performed, the hip molding process is performed. A surface treatment step may be performed before. For example, the surface treatment may be performed on the insulating film 42 after the insulating film 42 is formed into a predetermined size. Moreover, you may implement a surface treatment process before performing a trunk | drum shaping process, and any time after performing a trunk | drum shaping process and before performing a collar part shaping | molding process.

Next, a procedure for attaching the coil 16 to the tooth portion 18 of the stator core 15 will be described with reference to FIGS. 1 to 4, 6, and 11. FIG.
In the electric equipment bobbin 21 shown in FIG. 11 obtained by the above-described processing, an electric wire is wound around the outer periphery of the trunk portion 22. Thereby, as for the bobbin 21 for electric equipments, the coil 16 is provided in the outer periphery of the trunk | drum 22 as shown in FIG. Further, in the bobbin 21 for electric equipment, a filling member 26 is filled on the inner peripheral side of the body portion 22. The electric machine bobbin 21 provided with the coil 16 and filled with the filling member 26 is fitted into the tooth portion 18 of the stator core 15 from the inner peripheral side of the stator core 15 as indicated by an arrow F in FIG. Thereby, the coil 16 is in a state of being concentratedly wound around the teeth portion 18 with the bobbin 21 for electric equipment interposed therebetween. At this time, as shown in FIGS. 1 to 4, the tooth portion 18 is accommodated inside the right side wall 22c and the left side wall 22d of the body portion 22. On the other hand, the upper side wall 22 a and the lower side wall 22 b of the body part 22 are located outside the full length of the tooth part 18 in the axial direction of the stator core 15. The space between the body portion 22 and the tooth portion 18 is filled with a filling member 26. The stator core 15 is attached with an electric equipment bobbin 21 in which the coils 16 are provided in all the teeth portions 18.

Here, the line product ratio of the electric wire will be described with reference to FIG. In the conventional bobbin 101 for electric equipment shown in FIG. 14B, the body portion 102, the first flange portion 103, and the second flange portion 104 are integrally formed of the same resin and seamlessly by, for example, injection molding. . In this case, the thickness T ₀ of the body portion 102 needs to ensure a dimension that does not cause cracking at least after integral molding with a resin due to restrictions during molding. Therefore, the thickness T ₀ of the body portion 102 is required to be, for example, about T ₀ = 1 to 3 mm.

On the other hand, in the present embodiment, the right side wall 22c and the left side wall 22d of the body portion 22 are formed of an insulating film having a thickness T ₁ of T ₁ = 0.05 mm to 0.5 mm. Therefore, the line area ratio of the electric wires of the bobbin 21 for electric equipment according to the present embodiment is increased by an amount corresponding to (T ₀ -T ₁ ) compared to the bobbin 101 for electric equipment in the conventional configuration.

In general, when the current I (A) flows through a circular coil conductor, the magnetic flux density B at the axial center O of the coil is “B = μ ₀ Nl / 2r: where μ ₀ is the vacuum permeability, and N is The number of turns per meter, l is the length of the coil, and r is the radius of the coil. The trunk | drum 22 of 1st Embodiment is thin compared with the conventional trunk | drum 102 as above-mentioned. Therefore, the radius r _{1 of the} coil 16 provided on the outer periphery of the body portion 22 of the first embodiment is smaller than the radius r ₀ of the conventional coil by an amount corresponding to (T ₀ -T ₁ ). As a result, the coil 16 using the electric machine bobbin 21 of the first embodiment has a higher magnetic flux density than the conventional one. Therefore, the electrical equipment bobbin 21 of the first embodiment can improve the rotational efficiency of the rotating electrical machine 11 from the viewpoint of magnetic flux density.

According to the first embodiment described above, the body portion 22 of the bobbin 21 for electric equipment fitted to the teeth portion 18 of the stator core 15 has the thickness of the right side wall 22c and the left side wall 22d of 0.05-0. It is composed of a 5 mm insulating film. Therefore, the thickness of the right side wall 22c and the left side wall 22d of the trunk portion 22 is thinner than a bobbin formed by conventional insert molding. Therefore, more electric wires can be wound around the body portion 22 of the bobbin 21 for electric equipment, and the line area ratio of the electric wires can be increased. Further, since the body portion 22 becomes thin, heat generated from the electric wire is easily transmitted to the stator core 15 via the thin body portion 22. Therefore, the heat generated in the electric wire can be quickly diffused, and the heat dissipation can be improved. By increasing the heat dissipation, the rotating electrical machine 11 can achieve higher output and higher efficiency.

The bobbin 21 for an electric device according to the first embodiment has an engagement hole 22e at the end of the body portion 22 in the axial direction. As for the 1st collar part 23 and the 2nd collar part 24 which were provided in the edge part of the axial direction of the trunk | drum 22, the to-be-engaged part 25 has approached into the engagement hole 22e, respectively. Thereby, the joining strength of the trunk | drum 22 and the 1st collar part 23, and the trunk | drum 22 and the 2nd collar part 24 are joined by high intensity | strength. Therefore, the drop-off of the first flange part 23 and the second flange part 24 from the trunk part 22 can be reduced.

In the first embodiment, the first collar part 23 and the second collar part 24 are insert-molded with the body part 22 as an insert. Therefore, even when the body part 22, the first collar part 23, and the second collar part 24 are formed of different materials, manufacturing can be facilitated. At the same time, the first collar 23 and the second collar 24 are sufficiently thickened by insert molding. Therefore, the strength of the first collar part 23 and the second collar part 24 can be increased. Further, the body portion 22 is integrally joined to the first flange portion 23 and the second flange portion 24. Therefore, even when these are formed of different materials, the bobbin 21 for electrical equipment can be easily attached to components such as the stator core 15.

In the first embodiment, a filling member 26 is provided on the inner peripheral side of the body portion 22. The filling member 26 fills a step between the trunk portion 22 and the first and

second collar portions

23 and 24. Thereby, when the bobbin 21 for electric equipment is attached to the teeth part 18, the clearance gap between the trunk | drum 22 and the teeth part 18 is filled with the filling member 26 with fluidity | liquidity. Therefore, the heat generated by the electric wires constituting the coil 16 is transmitted from the filling member 26 to the stator core 15 via the trunk portion 22. Therefore, the heat dissipation of the coil 16 is improved, and the temperature rise of the coil 16 can be suppressed.

In the first embodiment, a surface treatment for improving wettability is performed on the surface of the insulating material before performing the trunk shaping process or after performing the trunk shaping process and before performing the hip molding process. ing. Thereby, the molten resin which forms the 1st collar part 23 and the 2nd collar part 24 becomes easy to flow along the insulating material which forms the trunk | drum 22 at the time of insert molding. Thereby, high adhesiveness is ensured with the resin which forms the 1st collar part 23 and the 2nd collar part 24, and the insulating material which forms the trunk | drum 22. Therefore, it is possible to increase the bonding strength between the body portion 22, the first flange portion 23, and the second flange portion 24, and it is possible to reduce cracks after molding.

(Second Embodiment)
The principal part of the bobbin 21 for electric equipment by 2nd Embodiment is shown in FIG. The 1st collar part 23 and the 2nd collar part 24 have a substantially symmetrical structure. Therefore, in FIG. 15, the periphery of the first collar part 23 is illustrated, and illustration and description of the second collar part 24 are omitted.
The 1st collar part 23 has a pair of clamping piece 23a, as shown in FIG. The pair of sandwiching pieces 23 a is provided at a position sandwiching the body portion 22 in the thickness direction of the body portion 22. The sandwiching piece 23 a is integrally formed with the same resin as that of the first flange 23 simultaneously with the first flange 23. One of the pair of sandwiching pieces 23 a is located on the inner side in the radial direction of the body portion 22. The other of the sandwiching pieces 23 a is located outside in the radial direction of the body portion 22.

In the case of the second embodiment, both ends of the engagement hole 22e are opposed to the pair of sandwiching pieces 23a in the radial direction of the body portion 22. That is, one end of the engagement hole 22e is opposed to the inner circumferential side sandwiching piece 23a, and the other end is opposed to the outer circumferential side sandwiching piece 23a. The engaged portion 25 protruding from the first flange 23 connects the pair of sandwich pieces 23 a in the radial direction of the body portion 22. That is, the engaged portion 25 penetrates the engagement hole 22 e and connects the pair of sandwiching pieces 23 a to each other in the radial direction of the trunk portion 22. Both ends of the engaged portion 25 are formed integrally with the sandwiching piece 23a. That is, when forming the first flange portion 23, the molten resin that becomes the first flange portion 23 forms the pinching piece 23a, and part of the resin enters the engagement hole 22e to form the engaged portion 25. To do. Thereby, the 1st collar part 23 forms the pinching piece 23a and the to-be-engaged part 25 integrally with resin.

In the second embodiment, the body portion 22 is fixed to the first flange portion 23 at a plurality of positions in the circumferential direction by the integral clip piece 23a and the engaged portion 25. Accordingly, the bonding strength between the body portion 22 and the first flange portion 23 can be further increased. In the case of 2nd Embodiment, the 2nd collar part 24 is the structure similar to the 1st collar part 23. FIG. Therefore, the second flange 24 can be firmly joined to the body 22 in the same manner as the first flange 23.

(Third embodiment)
Next, an electric equipment bobbin 71 according to a third embodiment is shown in FIGS. 16 and 17.
The bobbin 71 for electric equipment shown in FIG. 16 and FIG. 17 is provided with a connecting portion 72 for reinforcement. The connecting portion 72 is a side wall that connects the first flange portion 23 and the second flange portion 24. The connecting portion 72 is provided integrally with the first flange portion 23 and the second flange portion 24. The connecting portion 72 is provided on each of the upper side, which is the outer peripheral side of the upper side wall 22a, and the lower side, which is the outer peripheral side of the lower side wall 22b.
The bobbin 71 for electrical equipment is insert-molded with the body portion 22 as an insert as in the first embodiment. The connecting portion 72 is formed integrally with the first flange portion 23 and the second flange portion 24 during the insert molding. The thickness of the connecting portion 72 is arbitrarily set within a range that can be formed by insert molding. The thickness of the connecting portion 72 is set to 1 to 3 mm, for example.

In the third embodiment, the connecting portion 72 is provided between the first flange portion 23 and the second flange portion 24. The connecting portion 72 has a thickness larger than that of the trunk portion 22. For this reason, the strength of the body portion 22 against compression in the axial direction increases. Thereby, the deformation | transformation of the trunk | drum 22 is reduced. Therefore, the strength of the bobbin 71 for electric equipment can be increased.
In 3rd Embodiment, the connection part 72 is provided in the outer side of the upper side wall 22a and the lower side wall 22b, respectively. On the other hand, as for the trunk | drum 22, the right side wall 22c and the left side wall 22d are formed with the insulating film. Therefore, even if the connecting portion 72 is provided, the number of turns of the electric wire constituting the coil 16 is not affected. Therefore, the line area ratio of the electric wire can be increased while increasing the strength.

(Fourth embodiment)
18 and 19 show an electric equipment bobbin 81 according to the fourth embodiment.
The bobbin 81 for electric equipment shown in FIGS. 18 and 19 is provided with a connecting portion 82 for reinforcement. The connecting portion 82 is a side wall that connects the first flange portion 23 and the second flange portion 24. The connecting portion 82 is provided integrally with the first flange portion 23 and the second flange portion 24. The connecting portions 82 are respectively provided on the lower side, which is the inner peripheral side of the upper side wall 22a, and the upper side, which is the inner peripheral side of the lower side wall 22b.

The bobbin 81 for electric equipment is insert-molded by using the body portion 22 as an insert as in the first embodiment. The connecting portion 82 is formed integrally with the first flange portion 23 and the second flange portion 24 during the insert molding. The thickness of the connecting portion 62 is arbitrarily set within a range that can be formed by insert molding. The thickness of the connecting portion 82 is set to 1 to 3 mm, for example.
Similarly to the third embodiment, the fourth embodiment can also increase the strength of the bobbin 81 for electric equipment while increasing the line area ratio of the electric wires.

(Fifth embodiment)
An electric equipment bobbin 91 according to the fifth embodiment is shown in FIG.
The bobbin 91 for electrical equipment according to the fifth embodiment is press-molded instead of the insert molding in the above-described plurality of embodiments. In the case of the fifth embodiment, as shown in FIGS. 20 (b) and 20 (e), in the case of the body portion 22, both end portions in the axial direction are bent outward. Thereby, the trunk | drum 22 has the flange part 22f in the both ends of an axial direction. The engagement hole 22e is disposed in the flange portion 22f. Moreover, in the case of 5th Embodiment, the 1st collar part 23 and the 2nd collar part 24 are both 2 layer structures.

The first collar 23 has two first collar parts 23b and an adhesive member 92. As shown in FIGS. 20 (c) and 20 (e), the first flange portion 23b is formed by dividing the thickness of the first flange portion 23 into two equal parts. As shown in FIGS. 20D and 20E, the adhesive member 92 bonds the first flange part 23b and the body part 22 together. As shown in FIG. 20D, the adhesive member 92 is formed in a frame shape having the same shape as the first flange 23, for example. The adhesive member 92 is formed of an adhesive sheet having adhesiveness on both sides. In order from the end side in the axial direction, the first flange portion 23 is formed by laminating the first flange portion 23b, the adhesive member 92, the flange portion 22f of the body portion 22, the adhesive member 92, and the first flange portion piece 23b. It is provided integrally with the body portion 22. At this time, the engagement hole 22e is disposed between the two first flange portions 23b.

Similarly, the second collar part 24 has two second collar parts 24 b and an adhesive member 92. As shown in FIG. 20 (e), the second flange part 24 b is formed by dividing the thickness of the second flange part 24 into two equal parts. As shown in FIGS. 20D and 20E, the bonding member 92 bonds the second flange part 24b and the body part 22 together. The adhesive member 92 is formed of an adhesive sheet having adhesiveness on both sides, and is formed in a frame shape having the same shape as the second flange portion 24. In order from the end side in the axial direction, the second flange portion 24 is formed by laminating the second flange portion piece 24b, the adhesive member 92, the flange portion 22f of the body portion 22, the adhesive member 92, and the second flange portion piece 24b, It is provided integrally with the body portion 22. At this time, the engagement hole 22e is disposed between the two second flange pieces 24b. In the case of the fifth embodiment, the two first flange parts 23b correspond to sandwiching pieces. Similarly, the two second flange parts 24b correspond to sandwiching pieces.

Next, a manufacturing procedure of the bobbin 91 for electric equipment according to the fifth embodiment will be described.
The surface of the insulating film 42 constituting the body portion 22 is subjected to surface treatment such as plasma treatment. The step of performing the surface treatment corresponds to the surface treatment step. The details of the surface treatment are as described in the first embodiment, and a description thereof will be omitted. When the surface treatment is applied to the insulating film 42, the insulating film 42 is formed into a rectangular shape in which the body portion 22 is developed as shown in FIG. At this time, the insulating film 42 may form a cut portion 42a on the long side as shown in FIG. By forming the cut portion 42a, it becomes easy to bend in a later step. Note that the timing for performing the surface treatment is not limited as in the first embodiment.

The formed insulating film 42 is bent into a rectangular tube shape as shown in FIG. Further, the formed insulating film 42 is bent at both ends in the axial direction to the outer peripheral side. Thereby, the flange part 22f is formed. This process corresponds to a trunk shaping process.
The body part 22 formed in the body part shaping process shifts to the hip part forming process. Specifically, as shown in FIGS. 20 (e) and 20 (f), the flange portion 22f of the body portion 22 is provided with a first flange portion 23b, a second flange portion piece 24b, and an adhesive member 92. Laminated in order. Thereafter, the laminated members are formed into the first collar part 23 and the second collar part 24 by press molding. The first flange 23 is in the order of the first flange part 23b, the adhesive member 92, the flange part 22f of the trunk part 22, the adhesive member 92, and the first flange part 23b from the axial end of the body part 22. After being laminated, it is press-molded. Thereby, the adhesive member 92 adheres each member. Similarly, the second flange 24 includes the second flange 24b, the adhesive member 92, the flange 22f of the barrel 22, the adhesive member 92, and the second flange 24b from the end of the barrel 22 in the axial direction. After being laminated in this order, it is press-molded. Thereby, the adhesive member 92 adheres each member.

A part of the two adhesive members 92 sandwiching the flange portion 22f of the body portion 22 enters the engagement hole 22e of the flange portion 22f. Then, the adhesive members 92 on both sides of the flange portion 22f adhere to each other in the engagement hole 22e. Thereby, the flange part 22f of the trunk | drum 22 is firmly joined with the 1st collar part piece 23b and the 2nd collar part piece 24b by the adhesive member 92. FIG. In this case, a portion of the adhesive member 92 located in the engagement hole 22e corresponds to the engaged portion.
The obtained electrical equipment bobbin 91 is fitted into the teeth portion 18 of the stator core 15 shown in FIG. 1 in the same manner as the electrical equipment bobbin 21 of the first embodiment. Thereby, the insulating film of the trunk | drum 22 is located in the part located in the stator core 15 at least among the trunk | drums 22 of the bobbin 91 for electric equipments fitted to the teeth part 18 of the stator core 15. FIG.

According to the fifth embodiment described above, the thickness of the body portion 22 is reduced as in the first embodiment. Therefore, more electric wires than the coil 16 are wound around the bobbin 91 for electric equipment. Therefore, high output and high efficiency of the rotating electrical machine can be achieved.
Moreover, in 5th Embodiment, it replaces with insert molding and the 1st collar part 23 and the 2nd collar part 24 can be integrally formed in the trunk | drum 22 by press molding.

(Sixth to tenth embodiments)
Hereinafter, sixth to ninth embodiments will be described.
In the sixth embodiment, as shown in FIG. 21, the engagement hole 22g has a square cross section. In the seventh embodiment, as shown in FIG. 22, the engagement hole 22h has a triangular cross section. Furthermore, in the eighth embodiment, as shown in FIG. 23, a part of the engagement hole 22 i is opened at the outer edge of the insulating film 42. In the case of the eighth embodiment, it is preferable that the inner diameter of the engagement hole 22i increases toward the inner side of the insulating film 42. The engagement hole 22i having such a shape is tightly engaged with the engaged portion 25 that has entered. Therefore, the relative position shift of the trunk | drum 22 and the 1st collar part 23, and the 2nd collar part 24 can be reduced more. Thus, the shapes of the engagement holes 22g to 22i can be arbitrarily set. In the ninth embodiment, as illustrated in FIG. 24, the bobbin 21 for an electric device does not include a filling member on the inner peripheral side of the trunk portion 22. For example, when the heat generated in the coil 16 is small, the filling member 26 may be omitted as shown in the ninth embodiment.

Furthermore, as shown in FIG. 25, the bobbin 21 for an electric device may divide the body portion 22, the first flange portion 23, and the second flange portion 24 into two. Thereby, the bobbin 21 for electric equipment can pinch | interpose the teeth part 18 when attaching to the teeth part 18 of the stator core 15. FIG. The electric equipment bobbin 21 may be divided into two or more, and the division position is not limited to the above and can be arbitrarily set.

(Other embodiments)
The present invention is not limited to the embodiment described above and shown in the drawings, and the following modifications and expansions are possible.
The trunk | drum 22 demonstrated the example which comprises the upper side wall 22a, the lower side wall 22b, the right side wall 22c, and the left side wall 22d with the insulating film. However, it is only necessary that the body 22 has at least the right side wall 22c and the left side wall 22d made of an insulating film. In this case, the upper side wall 22 a and the lower side wall 22 b may be formed integrally with the first flange portion 23 and the second flange portion 24 with the same material as the first flange portion 23 and the second flange portion 24.

The connection part 72 in the third embodiment and the connection part 82 in the fourth embodiment have been described as being formed in a wall shape. However, the shape of the connecting portion 72 and the connecting portion 82 can be arbitrarily set, for example, formed in a plurality of columnar shapes. Further, the adhesive member 92 in the fifth embodiment has been described by taking an adhesive sheet as an example. However, the adhesive member 92 is not limited to an adhesive sheet, and may be an adhesive having general fluidity. The surface treatment in the plurality of embodiments has been described by taking the plasma treatment as an example, but is not limited thereto, and may be a corona treatment or a chemical treatment.

The embodiment described above is merely an example, and the material and thickness of the insulating film are determined as appropriate depending on the use of the bobbin for each electric device, and other materials, shapes, positions of connecting portions, etc. can be changed as appropriate. it can. Moreover, the bobbin for electric equipment can be applied not only to electric equipment such as a transformer and an inverter but also to an outer rotor type rotating electrical machine.

Claims

A barrel formed in a cylindrical shape with an insulating film;
A collar portion provided at each axial end portion of the body portion, the body portion being fitted on the inner peripheral side, formed of a material different from that of the body portion, and projecting annularly from the body portion radially outward. When,
An engagement hole that is provided at each end of the body in the axial direction, penetrates the body in the thickness direction, and enters the inner peripheral side of the flange that faces the body, and
Bobbin for electrical equipment comprising
The bobbin for an electric device according to claim 1, wherein the flange includes a pair of sandwiching pieces for sandwiching the axial end of the body from both sides in the radial direction.
The engaging hole has opposite end portions in the radial direction of the body portion, each facing a pair of the clip pieces,
The bobbin for an electric device according to claim 2, wherein the flange portion penetrates the engagement hole between the sandwiching pieces facing each other.
The bobbin for an electrical device according to claim 1, further comprising a filling member provided on a radially inner side of the trunk portion and the flange portion.
The bobbin for an electric device according to claim 1, wherein the body portion has a thickness of 0.05 mm to 0.5 mm.
The bobbin for an electric device according to claim 1, further comprising a connecting portion that is integrally formed with the flange portion and that connects and reinforces the flange portion provided at both axial end portions of the body portion in the axial direction. .
Forming an insulating material having a thickness of 0.05 mm to 0.5 mm into a cylindrical body;
Forming a flange having a larger outer diameter than the body part at both ends in the axial direction of the body part formed into a cylindrical shape integrally with the body part;
Manufacturing method of bobbin for electric equipment including
8. The method for manufacturing an electric equipment bobbin according to claim 7, further comprising a step of forming an engagement hole penetrating the body portion in a thickness direction at an end portion in the axial direction of the body portion in the step of forming the body portion. .
The method for manufacturing a bobbin for an electric device according to claim 7, wherein, in the step of forming the flange portion, the flange portion is injection-molded.
The method for manufacturing a bobbin for an electrical device according to claim 7, wherein, in the step of forming the flange portion, the barrel portion is disposed in a mold and the flange portion is insert-molded.
The method for manufacturing a bobbin for an electric device according to claim 7, further comprising a step of performing a surface treatment on the surface of the body portion.