JPH10270261A - Transformer device and coil device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten adhesive agent in curing time by a method, wherein the joint surface of a core, its adjacent part, and a coil bobbin and the core are bonded and fixed together with a foaming adhesive resin which is cured while foaming to exhibit its adhesive force. SOLUTION: A coil 3 mounted covering the legs 1a and 2a of cores 1 and 2 is equipped with a primary coil bobbin 4, wound with a primary coil 5 with a through-hole to which the legs 1a and 2a of the cores 1 and 2 are inserted and a secondary oil bobbin 6 wound with a secondary coil 7 located outside the primary coil 5. The primary coil bobbin 4 is fitted in an insulating case 8 and fixed, and the insulating case 8 is filled up with an insulating resin 9. A liquid resin 21 which is cured while foaming to exhibit its adhesive force is applied to the end joint surfaces of the legs 1a, 1b, 2a, and 2b, the cores 1 and 2 are fixed together, and the cores 1 and 2 and the primary coil bobbin 4 are fixed firmly, together with the protruding liquid resin 21.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transformer such as a converter transformer or a switching power supply transformer used for electric products, or a flyback transformer for supplying a high voltage to a cathode ray tube in a cathode ray tube display device such as a television receiver. The present invention relates to a device and a coil device such as an ignition coil and a choke coil for a vehicle.

[0002]

2. Description of the Related Art As electronic equipment such as AV equipment and information-related equipment, and power machinery such as vehicles, have fallen in price, demands for cost reduction of parts have become stronger. In particular, the demand for transformer devices and coil devices, which make up a large part of the component price, is becoming more severe, and competition between peers in Japan and overseas is becoming more intense. Therefore, production costs must be further reduced by reducing material costs, improving productivity and yield, and promoting energy saving in production processes, including changes in constituent materials and manufacturing methods.

[0003] Many transformer devices and coil devices usually use a core, and there are unexpectedly many process defects related to the fixing of the core, and poor product performance and appearance defects. At present, a lot of expenses such as jigs and tools and electric power are spent. Therefore, it has been urgently desired to develop a method of bonding and fixing the structure of a transformer device or a coil device to a core in a simple manner that can be automated at a low cost and in a short time.

Here, as an example of a conventional transformer device, a transformer device which is used to supply a high voltage to a cathode ray tube (CRT) such as a television receiver or a display monitor and which is generally called a flyback transformer is used. 13 will be described with reference to FIG. In FIG. 11, reference numerals 1 and 2 denote U-shaped (or U-shaped) cores, 1a and 1b denote legs of the core 1, 2a
And 2b are the legs of the core 2. The two U-shaped cores 1 and 2 have their legs 1a and 1b and the ends of the legs 2a and 2b interposed via gap spacers 10a and 10b of a predetermined size for preventing the core 1 and 2 from being saturated. They are joined to form a square core.

[0005] Further, reference numeral 3 denotes a coil portion mounted so as to cover one of the legs 1a and 2a of the cores 1 and 2. The coil unit 3 includes a primary coil bobbin 4 on which a primary coil 5 having a through hole into which one of the legs 1a and 2a of the cores 1 and 2 is inserted, and a secondary coil 7 disposed outside the primary coil bobbin 4. And a secondary coil bobbin 6 on which is wound. The primary coil bobbin 4 is fitted and fixed to an insulating case 8, and an insulating resin 9 for high-voltage insulation is provided in the insulating case 8.
Is filled.

The legs 1a, 1b, 2a, 2 of the cores 1, 2
Epoxy resin-based liquid adhesives 11a and 11b are applied to the joint surfaces between the ends of b.
The cores 1 and 2 are fixed by hardening 11b. Also, the cores 1 and 2 and the primary coil bobbin 4
And the adhesive 1 protruding from the joint surfaces of the legs 1a and 2a.
At 1a, it is adhesively fixed. Further, an adhesive 1 is provided between the bottom 4c of the primary coil bobbin 4 and the abdomen 2d of the core 2.
2 is applied and the adhesive 12 is cured to bond and fix the primary coil bobbin 4 and the core 2. Thus, the coil portion 3 and the cores 1 and 2 are firmly bonded and fixed to each other.

[0007]

As described above, in the transformer device 13, the legs 1a, 1 of the cores 1, 2 are provided.
b, 2a, and 2b are provided with an adhesive 11a,
11b is mounted on the gap spacer 10 having a predetermined size.
a and 10b, each leg 1a, 1b,
The ends of 2a and 2b are butted together. This adhesive 1
1a and 11b are hardened to fix the cores 1 and 2, and the adhesive 11 protruding from the joint surfaces of the legs 1a and 2a.
The gap between the ends of the legs 1a and 2a and the inner surface of the primary coil bobbin 4 is filled with a, and the adhesive 11a is hardened to bond and fix the coil 3 to the cores 1 and 2. This method of bonding and fixing the flyback transformer was previously proposed by the present applicant in Japanese Utility Model Application No. 59-63917 "Flyback Transformer".

However, each leg 1a, 1b, 2a, 2b
The amounts of the adhesives 11a and 11b to be put on the joint surfaces between the ends of the cores must be selected in accordance with the diameters of the cores 1 and 2, but the amounts may vary.
Due to a work error, the amount of the adhesive 11a, 11b may be smaller than the optimal predetermined amount. In this case, there are cases where the coil portion 3 and the cores 1 and 2 are not bonded and fixed, or where the bonding and fixing are incomplete. Then, when the transformer device 13 is attached to the device and operated,
Vibration occurs in the cores 1 and 2. And cores 1 and 2
Vibration noise in the audible frequency band, which is generated at the contact surface or contact point between the coil and the coil portion 3, becomes a problem. Further, there is a possibility that the cores 1 and 2 may come off from the transformer device 13 during transportation of the device, and may damage other components in the device, such as a CRT.

On the other hand, when the amounts of the adhesives 11a and 11b are larger than a predetermined amount, the bonding area between the cores 1 and 2 and the coil portion 3 increases, and the linear expansion coefficient between the cores 1 and 2 and the coil portion 3 increases. Are approximately one order of magnitude different, the cores 1 and 2 may be damaged by a temperature difference between the temperature at the time of curing and the room temperature in the curing process of the adhesives 11a and 11b, and the temperature difference between the time of operation and the time of stoppage in the device. There were also problems. As shown in FIG. 11, the bottom 4c of the primary coil bobbin 4 and the abdomen of the core 2 are used to solve the above-mentioned problem that occurs when the amounts of the adhesives 11a and 11b are smaller than a predetermined amount. When the adhesive 12 is applied between the core bobbin 2d and cured, and the primary coil bobbin 4 and the core 2 are bonded and fixed, the cores 1 and 2 may be damaged even if the amount of the adhesive 12 is appropriate. Had been a problem.

Further, as shown in FIG. 12, the legs 14a and 14b of the core 14 and the legs 15a and 15
b are the coil bobbins 18a and 1 of the coil unit 19, respectively.
8b, the ends of the legs 14a, 15a and the ends of the legs 14b, 15b are butted together via gap spacers 16a and 16b. Also in the transformer device 20 in which the core 14 and the adhesive 18b are bonded and fixed with epoxy resin adhesives 17a and 17b,
15 was damaged.

It has been found that these problems can be solved by replacing the epoxy resin-based adhesives 11a, 11b and 17a, 17b with silicone rubber resin-based adhesives. 60-54308 "Transformer". According to the method described in this prior application, even when the amount of the adhesive is larger than a predetermined amount, the elasticity of the adhesive absorbs the difference between the linear expansion coefficients of the cores 1, 2 or 14, 15 and the coil portion 3 or 19. In addition, the occurrence of core cracks can be completely eliminated.

However, the adhesive is used for the core 1, 2, or 14, 15 and the coil bobbin 4, or 18a, 18b.
And hardens by overflowing from the gap between
There is a possibility that a convex portion may be formed at the bottom of the. When these transformer devices 13 and 20 are mounted on a printed wiring board,
The loads of the transformer devices 13 and 20 are intensively applied to the convex portions, and there is a possibility that the printed wiring board is broken or the wiring pattern is cut during transportation or use of the device.

Further, the cores 1, 2 or 14, 15 and the coil 3 which are generated when the amount of the adhesive is smaller than a predetermined amount.
Alternatively, the problem of incomplete bonding with 19 or the problem of non-bonding cannot be still prevented. To prevent this problem, as shown in FIG. 11, the cores 1 and 2 and the primary coil bobbin 4 are
a, 2a, besides the adhesive 11a protruding from the joint surface, a bottom 4c of the primary coil bobbin 4
It is necessary to perform an additional operation of applying and curing the adhesive 12 between the core 2 and the abdomen 2d of the core 2 and bonding and fixing the primary side coil bobbin 4 and the core 2, thereby complicating the number of manufacturing steps.

However, even in this case, there is a case where the bonding and fixing are not sufficient, and it is impossible to prevent the vibration of the cores 1 and 2 which occurs when the apparatus is mounted and operated on the apparatus. However, there remains a problem that vibration noise in the audible frequency band generated at a contact surface or a contact point with the speaker cannot be eliminated.

Also, the primary coil bobbin 4 and the cores 1 and 2
When the gap is large, the required adhesive strength cannot be obtained. Conversely, when the gap is small, the adhesives 11a and 11b tend to overflow from the gap between the primary coil bobbin 4 and the cores 1 and 2. Considering the combination of the dimensional tolerances of the inner diameters of the cores 1 and 2 and the primary coil bobbin 4, the interval is limited to about 0.5 mm. Currently, cores 1 and 2 are
In some cases, the diameters of a, 1b, 2a, and 2b differ by about 0.5 mm. Legs 1 of these cores 1 and 2
A dedicated coil bobbin 4 is provided for each diameter of a, 1b, 2a, 2b, that is, structural components of the transformer device 13 are prepared according to the diameter of each leg 1a, 1b, 2a, 2b. It is a shackle of standardization, which is also a factor in high manufacturing costs.

Furthermore, many silicone rubber adhesives conventionally used do not exhibit sufficient adhesive strength unless they are cured at high temperatures for a long time.
For E322-B and the like, curing at 150 ° C. for 1 hour is a recommended value. Actually, the constituent material of the transformer device 13 is 150 ° C.
3 to 4 at 110 to 115 ° C.
The adhesive is cured over time. For this reason, a long time and a large amount of power are used to cure the adhesive, so that the production cost and the production lead time cannot be reduced. The above problems exist in the coil device in the same manner, and have to be solved.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and does not cause defective bonding in the bonding process, does not cause breakage or vibration of the core, and further reduces the curing time of the adhesive. It is an object of the present invention to provide a transformer device and a coil device that can perform the above operations.

[0018]

According to the present invention, there is provided a transformer device for forming a closed magnetic circuit by combining a pair of cores. Provided is a transformer device characterized in that a peripheral portion is bonded and fixed using a foaming adhesive resin which exerts an adhesive force by hardening while foaming, and (2) forming a closed magnetic circuit by combining a pair of cores (3) The coil device, wherein the bonding surface of the core and the peripheral portion thereof are bonded and fixed by using a foaming adhesive resin which hardens while foaming and exhibits an adhesive force.
In a coil device in which a core is inserted into a core insertion hole of a coil bobbin, the coil bobbin and the core are bonded and fixed using a foaming adhesive resin that hardens while foaming and exhibits an adhesive force. A coil device is provided.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a transformer device and a coil device according to the present invention will be described with reference to the accompanying drawings. 1 is a partially cutaway side view showing a first embodiment of the transformer device of the present invention, FIG. 2 is an exploded perspective view of the first embodiment of the transformer device of the present invention, and FIG. FIG. 4 is a perspective view for explaining a manufacturing process of one embodiment. FIG. 4 is a partially cutaway side view showing a second embodiment of the transformer device of the present invention.
Is a perspective view showing a third embodiment of the transformer device of the present invention, FIG. 6 is a side view showing a third embodiment of the transformer device of the present invention,
FIG. 7 is a sectional view showing a fourth embodiment of the transformer device of the present invention, FIG. 8 is a partially cutaway perspective view showing the first embodiment of the coil device of the present invention, and FIG. FIG. 10 is a partially broken side view showing two examples, and FIG. 10 is a diagram showing a curing temperature-time curve of an adhesive for comparing the present invention with a conventional example. 1 to 6, the same parts as those in FIG. 11 are denoted by the same reference numerals.

First, a description will be given of a first embodiment of the transformer device according to the present invention. In FIG. 1, reference numerals 1 and 2 denote U-shaped (or U-shaped) cores, reference numerals 1 a and 1 b denote legs of the core 1, and reference numerals 2 a and 2 b denote legs of the core 2. The two U-shaped cores 1 and 2 are connected to each other by a leg 1
a, 1b and the ends of the legs 2a, 2b are provided with gap spacers 10a,
They are joined together via 10b to form a square-shaped core.
Thereby, the cores 1 and 2 form a closed magnetic circuit.

Further, reference numeral 3 denotes a coil unit mounted so as to cover one of the legs 1a and 2a of the cores 1 and 2. The coil unit 3 includes a primary coil bobbin 4 on which a primary coil 5 having a through hole into which one of the legs 1a and 2a of the cores 1 and 2 is inserted, and a secondary coil 7 disposed outside the primary coil bobbin 4. And a secondary coil bobbin 6 on which is wound. The primary coil bobbin 4 is fitted and fixed to an insulating case 8, and an insulating resin 9 for high-voltage insulation is provided in the insulating case 8.
Is filled.

Each leg 1a, 1b, 2a, 2 of the cores 1, 2
A liquid resin 21 which is an essential part of the present invention and which hardens while foaming and exhibits an adhesive force is applied to the joint surface between the end portions b. By curing the liquid resin 21, the cores 1 and 2 are hardened. Is fixed. The cores 1 and 2 and the primary coil bobbin 4 are firmly bonded and fixed with a liquid resin 21 protruding from the joint surfaces of the legs 1a and 2a. As the liquid resin 21 which is an expandable adhesive resin, for example, a silicone liquid foam can be used. As the silicone liquid foam, a two-part addition reaction type silicone liquid foam sold by Shin-Etsu Chemical Co., Ltd., model number KE521 can be used.

Here, referring to FIG. 2 and FIG.
One method of the fixing procedure 2 will be described in more detail. In FIG. 2, a predetermined amount of a liquid resin 21 that hardens while foaming and exhibits an adhesive force is placed on the joint surfaces 2ac and 2bc at the ends of the legs 2a and 2b of the core 2. in addition,
The gap spacers 10a and 10b of a predetermined size for preventing the saturation phenomenon of the cores 1 and 2 are mounted. The leg portion 2a of the core 2 is inserted into the core insertion hole 4a of the primary coil bobbin 4 forming the coil portion 3 from the direction of arrow A.
The leg 1 a of the other core 1 is inserted into the core insertion hole 4 a from the direction of the arrow B opposite to the core 2.

Thereafter, as shown in FIG. 3, the cores 1 and 2 are sandwiched between jigs 24. By this sandwiching, the joining surface 2
The liquid resin 21 placed on ac and 2bc protrudes from the joint surfaces 1ac, 1bc, 2ac, 2bc of the cores 1, 2. This phenomenon will be described in more detail with respect to the joint between the legs 2a and 2b of the cores 1 and 2. First, on the side of the leg 1a of the core 1 and the leg 2a of the core 2 inserted into the core insertion hole 4a of the primary coil bobbin 4, the joint surfaces 1ac,
The excess liquid resin 21 pressed by 2ac is in a state of protruding from the joining surfaces 1ac, 2ac into the inner surface of the primary coil bobbin 4 and the gap 22 (shown in FIG. 1) near the ends of the legs 1a and 2a. On the other leg 1b, 2b side where only the legs are joined, the joining surfaces 1bc, 2
The excess liquid resin 21 pressed by bc is applied to the bonding surface 1
bc, 2bc, and as shown in FIG.
b and 2b are covered.

In this state, the hanger portion 24b provided on the convex portion 24a of the jig 24 holding the cores 1 and 2 is hooked on the adhesive curing base (not shown) while lifting the coil portion 3. Then, by curing the liquid resin 21 at room temperature or in a heated state, the liquid resin 21 is cured while foaming due to a chemical reaction and exhibits an adhesive force. Therefore, the inner surface of the primary coil bobbin 4 and the ends of the legs 1a and 2a are formed. At the same time, the joints 1ac and 2ac are also adhesively fixed. In addition, the leg portions 1b and 2b also have a joint surface 1b.
c, 2bc and near the ends near the joining surfaces 1bc, 2bc are adhesively fixed, and the legs 1b, 2b are firmly adhesively fixed. After the liquid resin 21 has hardened, the jig 24 is removed to obtain a transformer device 23 having a square-shaped closed magnetic path.

Generally, the viscosity of a liquid resin decreases as the liquid temperature increases, and the liquid resin increases in viscosity as the curing reaction proceeds, and is cured through a gel state. In the conventional adhesive, the adhesive that has protruded from the joint surfaces 1ac and 2ac of the cores 1 and 2 drips due to the decrease in viscosity that occurs during the curing process of the adhesive.
The contact area between the cores 1 and 2 and the coil portion 3 becomes large, and the cores 1 and 2 are damaged, the printed wiring board on which the transformer device is mounted is broken, and the wiring pattern is cut for the reasons described above. there were.

However, when the liquid temperature rises, the liquid resin 21 which is foamed and hardened by the chemical reaction used in the present invention is foamed before the resin protruding from the joint surfaces 1ac and 2ac of the cores 1 and 2 decreases in viscosity. The thickening of the core 1
2, the side surfaces of the legs 1a, 1b, 2a, 2b, and the legs 1a,
Since it thickens and hardens before the sagging phenomenon from the gap 22 between 2a and the inner surface of the primary side coil bobbin 4 occurs, it has been found that defects due to the sagging of the adhesive can be completely eliminated. Further, the degree of swelling of the liquid resin 21 after being cured by foaming is determined by the foaming ratio of the resin used, so that the distance between the gaps 22 between the legs 1a and 2a of the cores 1 and 2 and the inner surface of the primary coil bobbin 4, The optimum expansion ratio may be appropriately selected depending on the required strength of the adhesive fixing.

In the transformer device 23 of the present invention configured as described above, even when the amount of the liquid resin 21 is smaller than the optimum predetermined amount, the liquid resin 21 expands and the inner surface of the primary coil bobbin 4 and the core Since the gaps 22 between the legs 1a and 1b are filled and pressed with a large contact area and have a large rubber elastic force, it is as if the cores 1 and 2
The same effect as in the case where a highly elastic rubber packing is inserted between the leg portions 1a and 2a and the inner surface of the primary coil bobbin 4 and bonded and fixed. Therefore, the shock absorbing power and the vibration absorbing power are large, and all the problems that occurred when the amount of the adhesive is smaller than the predetermined amount can be solved satisfactorily.

That is, it is possible to eliminate the occurrence of poor bonding in the bonding step, such as incomplete bonding between the cores 1 and 2 and the coil portion 3, and to reduce the occurrence of cores when the apparatus is mounted and operated. Vibrations of 1 and 2 are also absorbed, and vibration noise in the audible frequency band generated by contact between the cores 1 and 2 and the coil section 3 can be eliminated. Also, during transportation,
Can be disengaged from the coil unit 3 of the transformer device 23, and there is no possibility that other components in the device may be damaged. Further, due to the difference in the coefficient of linear expansion between the cores 1 and 2 and the coil portion 3, the stress on the cores 1 and 2 due to the temperature difference during the manufacturing process and the operation of the device can be absorbed, and the cores 1 and 2 are damaged by the temperature difference. No problems occur.

Therefore, in the transformer device 23 of the present invention, as described in the conventional example of FIG. 11, the adhesive 12 is applied and cured between the bottom 4c of the primary coil bobbin 4 and the abdomen 2d of the core 2. It is not necessary to bond and fix the primary side coil bobbin 4 and the core 2.

Further, when the amount of the liquid resin 21 is larger than a predetermined amount, which is another problem, the bonding surface 1a
Liquid resin 2 protruding from c, 1bc, 2ac, 2bc
Thickening due to foaming progresses before the viscosity of the rubber 1 decreases, and the side surfaces of the legs 1a, 1b, 2a, 2b and the legs 1a,
Since the resin is cured before the dripping phenomenon from the gap 22 between the inner surface of the primary coil bobbin 2a and the inner surface of the primary coil bobbin 4, the above-mentioned conventional problems do not occur at all. Moreover, when the liquid resin 21 foams, the liquid resin 21 spreads almost uniformly in the vertical direction of the gap 22 instead of dropping and spreading mainly downward only as in the conventional adhesives 11a and 11b. This means that it has twice the absorption capacity.

Further, since the volume of the liquid resin 21 increases after foaming and curing, the amount of the liquid resin 21 is 1/3 to 1 / l of the conventional adhesive amount.
A sufficient adhesive strength is obtained with about 4. Therefore, the liquid resin 2
No. 1 can reduce the amount of the adhesive to about 1/3 as compared with the conventional adhesives 11a and 11b. This liquid resin 21
In addition to the fact that the amount of the liquid resin 21 is small before the above-mentioned sagging occurs and that the expansion due to foaming spreads in the vertical direction of the gap 22, the liquid resin 21
There is very little chance of overflowing more than two. Even if the liquid resin 21 overflows from the gap 22, since the liquid resin 21 is a foam, it can absorb mechanical stress due to sponge elasticity and does not act such as breaking a printed wiring board. Therefore,
Conventional problems can be solved well.

FIG. 4 shows a second embodiment of the transformer device according to the present invention. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. The transformer device 29 of the second embodiment uses U-shaped cores 25 and 26 having a smaller diameter than the cores 1 and 2 of the transformer device 23 shown in FIG. Then, similarly to the first embodiment, the core 2
5, 26, respectively, legs 25a, 25b and 26a,
The joint surfaces at the ends of the cores 26b are connected to the joint surfaces of the cores 25 and 26 and the leg 25a via gap spacers 10a and 10b of a predetermined size and a liquid resin 28 which cures while foaming to exert an adhesive force. , 26a and the inner surface of the primary coil bobbin 4 are firmly adhered and fixed.

In FIG. 4, the gap 27 between the inner surface of the primary coil bobbin 4 and the core leg portions 25a and 26a is reduced by using a relatively large resin having a foaming ratio of 3 to 6 times. Even if the difference between the inner diameter of the primary coil bobbin 4 and the diameter of the cores 25 and 26 is about 2 to 4 mm, the liquid resin 28 is
From the joint surface to the gap 27 near the joint surface, and is foamed 3 to 6 times by a chemical reaction to be cured and exhibit an adhesive force. Therefore, the inner surface of the primary coil bobbin 4 and the core 25,
Even if the gap 27 between the legs 26a and 26a is large,
The primary coil bobbin 4 and the cores 25 and 26 are satisfactorily adhered and fixed.

Also, on the side of the other leg 25b, 26b where only the leg is joined, the leg 25b, 26b
Extra liquid resin 28 pressed between the joint surfaces of
However, since the liquid resin 28 protrudes from the joint surface and hardens while foaming due to a chemical reaction to exert an adhesive force, the liquid resin 28 does not droop, and as shown in FIG.
5b and 26b are covered. As a result, the legs 25b and 26b are bonded and fixed. As the liquid resin 28 as the foamable adhesive resin, a two-part silicone liquid foam can be used as in the case of the liquid resin 21.

As described above, if the expansion ratio of the liquid resin as the foamable adhesive resin is appropriately selected, in a transformer device using a plurality of cores having different leg diameters, the components of the coil portion can be shared. It can be used. Therefore, unlike the related art, it is not necessary to prepare a coil portion corresponding to the diameter of the core leg, and standardization of parts can be performed, and costs such as mold costs and member management costs can be greatly reduced. At the same time, it has significant effects such as speeding up development and shortening the production lead time. In particular, when producing various types of models with different core diameters and small production quantities, the components of the coil section, dies and jigs and tools can be shared, which is necessary for parts procurement, management, and setup change due to model change. Man-hours and costs can be significantly reduced, greatly contributing to the reduction of manufacturing costs.

FIGS. 5 and 6 show a third embodiment of the transformer device of the present invention. Here also, the description will focus on the features of the third embodiment. The transformer device 34 of the third embodiment uses a liquid resin 32 of about 10 times larger in expansion ratio than the transformer devices 23 and 29 of the first and second embodiments. The feature is to cover the decrease in the adhesive fixing force due to the decrease in the tensile strength of the adhesive resin after curing due to the large expansion ratio, by increasing the number of adhesive parts so that the necessary adhesive strength can be obtained. . In addition, as the liquid resin 32 as the foaming adhesive resin, the liquid resins 21 and 28 are used.
Similarly, a two-part silicone liquid foam can be used.

In FIG. 5, reference numeral 31 denotes a case constituting the coil unit 30, and 31a and 31b denote core holding plates provided in the case 31. Inside of coil part 30 and core 2
For the bonding structure of the round legs 5 and 26 (the legs 25a and 26a), the transformer device 29 of the second embodiment shown in FIG.
Is the same as

The corner legs of the cores 25, 26 (legs 25b, 2
The bonding procedure of (6b side) is almost the same as that of the transformer devices 23 and 29, but in the third embodiment, it is performed as follows. That is, on the joint surface of the end of the leg 26 b of the core 26,
A predetermined amount of a liquid resin 32 which is hardened while foaming by a chemical reaction and exhibits an adhesive force is placed thereon, and the joint surfaces of the ends of the legs 25b of the other core 25 are opposed to each other via a gap spacer, so that the cores 25 and 26 are joined. Pinch each other. In some cases, the gap spacer is not inserted into the corner leg side. The liquid resin 32 protruding from the joint surface fills a gap (not shown) near the inner surface of the primary coil bobbin 4 and the end on the round leg side, and joins the cores 25 and 26 as shown in FIG. Core holding plates 31a, 31b near the corners and the corner legs (legs 25b, 2).
Fill the gap 33 with 6b). When the liquid resin 32 is cured and adhered, the core 25,
The two legs 25a, 25b, 26a, 26b of 26 are adhesively fixed, thereby preventing a decrease in adhesive strength due to a large expansion ratio.

With such a configuration, in a transformer device or a coil device using a plurality of cores having different diameters of the legs, it becomes possible to share the components of the coil portion. Therefore, unlike the related art, it is not necessary to prepare a coil portion corresponding to the diameter of the core leg, and standardization of parts can be performed, and costs such as mold costs and member management costs can be greatly reduced. At the same time, it has significant effects such as speeding up development and shortening the production lead time. In particular, when producing various types of models with different core diameters and small production quantities, the components of the coil section, dies and jigs and tools can be shared, which is necessary for parts procurement, management, and setup change due to model change. Man-hours and costs can be significantly reduced, greatly contributing to the reduction of manufacturing costs.

FIG. 7 shows a fourth embodiment of the transformer device according to the present invention, which is a transformer device 44 which is frequently used for an ignition coil for a vehicle or the like. This transformer device 4
Reference numeral 4 denotes a type in which a magnet for applying a reverse bias is inserted into a magnetic path formed by the core in order to reduce the size and weight of the core and reduce the size of the transformer device 44. Adhesion and fixation of the joint surface between the magnet and the core and the coil portion, and adhesion and fixation of the joint surface between the leg portions of the core where the magnet is not inserted, are foamed by a chemical reaction and hardened while exhibiting adhesion. It is characterized by using a liquid resin which absorbs the vibration of the core to prevent the magnet and the coil from being damaged.

In FIG. 7, a primary coil 38 and a secondary coil 39 are accommodated in a coil case 40 made of a suitable resin and having an opening at one end (upper side in the figure). The primary coil 38 is wound around a cylindrical primary coil bobbin 37. Primary coil bobbin 37
Both ends of the coil case 40, that is, an upper end portion in the drawing which is an opening side of the coil case 40 and a bottom portion 40a which is a lower end portion are open,
The hollow portion forms a core passage that passes through the inside of the coil case 40. The coil case 40 is filled with an appropriate insulating resin 41 such as an epoxy resin. The primary coil bobbin 37 and the bottom 40a of the coil case 40 are fitted by an appropriate method so that the insulating resin 41 does not leak.

In the hollow portion of the primary coil bobbin 37,
By combining two symmetrical U-shaped cores 35 and 36, a part of the square-shaped core is inserted. One of the legs 35a and 36a is connected to the other leg 3
5b and 36b, each leg 3
When 5a and 36a are respectively inserted into the hollow portion of the primary coil bobbin 37 from opposite sides, a predetermined gap is formed between the distal ends thereof. Accordingly, the legs 35a and 36a are in a separated state in the primary coil bobbin 37, and the magnet 42
Is inserted.

The magnet 42 is made of a permanent magnet, and is disposed so as to apply a reverse bias to the magnetic flux direction φ of a closed magnetic path formed in a square shape formed with the U-shaped cores 35 and 36. . Further, the surface of the magnet 42,
A liquid resin that hardens while foaming due to a chemical reaction to exert an adhesive force between the end faces of the legs 35a, 36a of the cores 35, 36 sandwiching this surface and between the other legs 35b, 36b. 43 is interposed. Thereby, between the surface of the magnet 42 and the end faces of the legs 35a, 36a, and
Near the end faces of the legs 35a and 36a and the primary coil bobbin 3
The inside of the hollow portion 7 is firmly bonded and fixed, and the end surfaces of the legs 35b and 36b on the side where the magnet 42 is not inserted and the peripheral portion thereof are also firmly bonded and fixed. In this way, the cores 35 and 36 are connected and integrated, and are also fixed to the coil portion.

As described above, since the foam made of the liquid resin 43 having cushioning property is interposed between the magnet 42 and the end surfaces of the legs 35a and 36a, the foaming material having cushioning properties is used for each leg. Since the vibration applied to the magnet 42 and the primary coil bobbin 37 from the sides 35a and 36a is absorbed, the magnet 42 and the primary coil 37 are protected against the vibration of the cores 35 and 36, and are less likely to be damaged during use. Therefore, the durability of the transformer device 44 can be greatly improved. In addition, as the liquid resin 43 which is a foaming adhesive resin, the liquid resin 2
Like 1,28,32, a two-part silicone liquid foam can be used.

In the transformer devices 23, 29, 34, and 44 of this embodiment shown in FIGS. 1 to 7 described above, the case where the U-shaped magnetic path is formed using the U-shaped core has been described. Various shapes such as a UI shape and an LL shape can be used for the core. The shape of the core is arbitrary.

FIG. 8 shows a coil device 52 which is a first embodiment of the coil device of the present invention. This coil device 5
2 is used, for example, as a choke coil. In FIG. 8, reference numerals 45 and 46 denote E-shaped cores. 45a to 45c are legs of the core 45, and 45a is a center leg (middle leg). 46a to 46c are the core 4
Reference numeral 6 denotes a leg, and reference numeral 46a denotes a central leg (middle leg). The center legs 45a and 46a of the cores 45 and 46 are provided with two leg portions 45b and 46b in order to provide a gap space 50 of a predetermined size in order to prevent a saturation phenomenon of the cores 45 and 46.
And 45 c and 46 c shorter by the gap space. The gap space 50 is formed in the middle leg 45a.
Or you may provide only in 46a.

A coil 48 is wound around a cylindrical portion 47c between a lower flange 47a and an upper flange 47b of the coil bobbin 47. The middle leg portion 46a of the core 46 is inserted from below into the through hole of the cylindrical portion 47c of the coil bobbin 47, and the two leg portions 46b,
46c is inserted from below into through holes 49 provided on both sides of the lower flange 47a of the coil bobbin 47. Legs 46a, 4
A liquid resin 51 which is hardened while foaming by a chemical reaction and exerts an adhesive force is placed on the ends of 6b and 46b, and the middle leg 45a of the core 45 is inserted from above into the through hole of the cylindrical portion 47c of the coil bobbin 47, The cores 45 and 46 and their peripheral portions are fixed by bonding.

This bonding and fixing is performed by the two legs 45b, 45c,
46b, 46c and the middle legs 46a, 46b,
Either of the two legs 45b, 45c, 46b, 46c may be used as long as a predetermined adhesive strength is obtained. In the above description, the embodiment using the E-shaped cores 45 and 46 has been described. However, even if the EI-shaped core is joined to the coil bobbin 47 on the flange 47a side using the EI-shaped core, the flange 47b may be used.
It may be done on the side.

FIG. 9 is a partial sectional side view of a coil device 58 in which a rod-shaped core is bonded and fixed to a coil bobbin. The coil device 58 is used for various purposes, for example, as an inductor. In FIG. 9, 53 is a coil bobbin, 5
3a is a core insertion hole of the coil bobbin, 54 is a rod-shaped core, 5
5a and 55b are coils wound around the coil bobbin 53, 56 is a hole provided on the coil bobbin 53, and 57 is a liquid resin which foams and hardens while exhibiting an adhesive force by a chemical reaction. As the liquid resin 57 as the foamable adhesive resin, a two-liquid silicone liquid foam can be used as in the case of the liquid resins 21, 28, 32, and 43.

The hole 56 is provided in an unwound portion of the coil 55a, 55b of the cylindrical portion of the coil bobbin 53. The rod-shaped core 54 is inserted into the core insertion hole 53 a, and a liquid resin 57 is poured from a hole 56 provided in the coil bobbin 52, and the side surface of the rod-shaped core 54 and the inner surface of the coil bobbin 53 are bonded and fixed. The liquid resin 57 may be poured before or after the insertion of the rod-shaped core 54.
When pouring the liquid resin 57 before the insertion of the
Before the curing reaction of No. 7 starts, the rod-shaped core 54 is inserted into the core insertion hole 5.
3a.

Here, the liquid resin (2
1, 28, 32, 43, 57) and the adhesive strength will be described with reference to Tables 1 and 2.

[0053]

[Table 1]

[0054]

[Table 2]

In Table 1, the liquid resins (21, 28,
Resins A to D of Examples used as Examples 32, 43, 57)
And the characteristics of TSE322-B, which is a conventional adhesive. The liquids A and B of the resins A to D indicate one and the other of the two-component liquid resins. The pot life is the usable time that can be applied to the bonding process, and 3
One that can be cured in a short time of a minute or one that is cured in a long time of about 10 hours can be appropriately selected.
As an example of application, a conventional transformer device 20 shown in FIG. 12 is also added. This shows that the liquid resin of the present embodiment can be used for the transformer device 20 having the configuration shown in FIG. ing.

In Table 2, Examples 1 to 5 of transformer devices (23 and the like) using resins A to D and transformer device (13) using TSE322-B, which is a conventional adhesive, are used.
5 shows the tensile strength of the core in the vertical direction. In general, a cured product that exhibits an adhesive strength by curing while liquid resin foams by a chemical reaction becomes coarser sponge as the expansion ratio increases, so the tensile strength decreases, and the adhesive fixing strength per unit area Drops. However, as shown in Table 2, in Examples 1 to 5, sufficient strength to be used as an adhesive for a transformer device or a coil device is obtained.

The curing of the liquid resin in this embodiment may be carried out at room temperature or by heating using a curing furnace.
FIG. 10 shows the curing temperature-time curves of the liquid resin of this embodiment and the conventional example. When the liquid resin used for bonding the cores of the transformer device and the coil device is cured by heating and bonded and fixed, the curing time varies slightly depending on the size (heat capacity) of the transformer device and the coil device, but the predetermined temperature (for example, 115 C), the liquid resin is heated and gradually rises in temperature to reach a predetermined temperature. FIG.
As shown in (1), in the conventional example, a heating time of about 200 minutes is required, but in the present embodiment, a heating time of about 50 minutes is sufficient. Of course, in the present invention, as described above, it is also possible to cure at room temperature without using heating.

In this embodiment described above, an example was described in which a silicone liquid foam was used as the foamable adhesive resin used as the adhesive, but another foam such as a urethane liquid foam was used. Those having the same action and effect can be similarly used. In addition, in the case of a structure in which not only the addition reaction type silicone liquid foam but also the metal members constituting the transformer device and the coil device do not corrode, a condensation reaction type silicone liquid foam can be used.

Further, the expansion ratio of the liquid resin is described as being 2.1 to 10.0 times in the embodiment. However, the resin does not sag during curing and can absorb vibration. There is sponge elasticity, and
It is only necessary to be able to fill the gap between the core side surface and the bonded part of the transformer device or the coil device. Therefore, if the structure of the bonded part is appropriately devised, the effect can be sufficiently exerted if the expansion ratio is about 1.3 times. Can be.

[0060]

As described above in detail, in the transformer device and the coil device of the present invention, the bonding surface of the core and its peripheral portion, and the coil bobbin and the core are hardened while being foamed to exert an adhesive force. Adhesion and fixation using foaming adhesive resin, without causing adhesion failure in the adhesion process,
The curing time of the adhesive can be further reduced without causing breakage or vibration of the core. Further, it is possible to significantly reduce the manufacturing cost.

[Brief description of the drawings]

FIG. 1 is a partially broken side view showing a first embodiment of a transformer device of the present invention.

FIG. 2 is an exploded perspective view of the first embodiment of the transformer device of the present invention.

FIG. 3 is a perspective view for explaining a manufacturing process of the first embodiment of the transformer device of the present invention.

FIG. 4 is a partially broken side view showing a second embodiment of the transformer device of the present invention.

FIG. 5 is a perspective view showing a third embodiment of the transformer device of the present invention.

FIG. 6 is a side view showing a third embodiment of the transformer device of the present invention.

FIG. 7 is a sectional view showing a fourth embodiment of the transformer device of the present invention.

FIG. 8 is a partially broken perspective view showing a first embodiment of the coil device of the present invention.

FIG. 9 is a partially broken side view showing a second embodiment of the coil device of the present invention.

FIG. 10 is a diagram showing a curing temperature-time curve of an adhesive for comparing the present invention with a conventional example.

FIG. 11 is a partially broken side view showing an example of a conventional transformer device.

FIG. 12 is a partially broken side view showing another example of the conventional transformer device.

[Explanation of symbols]

1,2,25,26,35,36,45,46 cores 1a, 1b, 2a, 2b, 25a, 25b, 26a, 2
6b, 35a, 35b, 36a, 36b, 45a to 45
c, 46a to 46c Legs 1ac, 1bc, 2ac, 2bc Joining surface 3, 30 Coil 4, 37 Primary coil bobbin 5, 38 Primary coil 6 Secondary coil bobbin 7, 39 Secondary coil 8 Insulating case 9, 41 Insulating resin 10a, 10b, 50 Gap spacer 21, 28, 32, 43, 57 Liquid resin (expandable adhesive resin) 22, 27, 33 Gap 23, 29, 34, 44 Transformer device 31a, 31b Core holding plate 40 Coil Case 42 Magnet 52, 58 Coil device 53 Coil bobbin 53a Core insertion hole 54 Bar-shaped core 55a, 55b Coil

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] July 9, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0051

[Correction method] Change

[Correction contents]

The hole 56 is provided in an unwound portion of the coil 55a, 55b of the cylindrical portion of the coil bobbin 53. The rod-like core 54 is inserted into the core insertion hole 53a, the hole 56 provided in the coil bobbin 3, pouring the liquid resin 57 is bonded and fixed to the inner surface side and a coil bobbin 53 of the rod-shaped core 54. The liquid resin 57 may be poured before or after the insertion of the rod-shaped core 54.
When pouring the liquid resin 57 before the insertion of the
Before the curing reaction of No. 7 starts, the rod-shaped core 54 is inserted into the core insertion hole 5.
3a.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0060

[Correction method] Change

[Correction contents]

[0060]

As described above in detail, in the transformer device and the coil device of the present invention, the bonding surface of the core and its peripheral portion, and the coil bobbin and the core are hardened while being foamed to exert an adhesive force. Adhesion and fixation using foaming adhesive resin, without causing adhesion failure in the adhesion process,
The hardening time of the adhesive can be further reduced without causing breakage of the core or vibration noise . Further, it is possible to significantly reduce the manufacturing cost.

Claims (9)

[Claims] 1. A transformer device for forming a closed magnetic circuit by combining a pair of cores, wherein a bonding surface of the core and a peripheral portion thereof are bonded by using a foaming adhesive resin which is hardened while foaming to exhibit an adhesive force. A transformer device characterized by being fixed. 2. The transformer device according to claim 1, wherein a two-component addition reaction type silicone liquid foam is used as the foamable adhesive resin. 3. The transformer device according to claim 2, wherein said addition-reaction type silicone liquid foam has a foaming ratio of 1.3 to 10.0 times. 4. A coil device for forming a closed magnetic circuit by combining a pair of cores, wherein a bonding surface of the core and a peripheral portion thereof are bonded by using a foaming adhesive resin which hardens while foaming and exhibits an adhesive force. A coil device characterized by being fixed. 5. The coil device according to claim 4, wherein a two-component addition reaction type silicone liquid foam is used as the foamable adhesive resin. 6. The coil device according to claim 5, wherein the expansion ratio of the addition-reaction silicone liquid foam is 1.3 to 10.0 times. 7. A coil device in which a core is inserted into a core insertion hole of a coil bobbin, wherein the coil bobbin and the core are bonded and fixed using a foaming adhesive resin which hardens while foaming and exhibits an adhesive force. A coil device characterized by the above-mentioned. 8. The coil device according to claim 7, wherein a two-component addition-reaction-type silicone liquid foam is used as the foamable adhesive resin. 9. The coil device according to claim 8, wherein the expansion ratio of the addition reaction type silicone liquid foam is 1.3 to 10.0 times.