JPH0435890B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field to Which the Invention Pertains] The present invention relates to a method for winding a strip coil for a stationary induction appliance, particularly a strip coil for a resin molded induction appliance.

[Prior art and its problems] Figure 4 is a side sectional view showing an example of the prior art of resin molded winding using a strip coil.
A plurality of strip coils 1 such as B and 1C are integrally molded in a mold resin 2 made of a cured epoxy resin mixed with an inorganic filler, and embedded terminal fittings 6 are provided in a predetermined angular direction. The strip coils 1A, 1B, 1C, etc. each have a thin strip-shaped strip conductor 4 made of aluminum, copper, etc. and an insulating sheet 5 made of polyester film, kraft paper, etc. on the outside of a winding frame 3 made of cylindrical pressboard, FRP, etc.
The strip conductor in contact with the winding frame 3 and the beginning of the insulating sheet are fixed to the winding frame with adhesive tape, and the winding frame and the strip coil are insulated at key points. The shape of the strip coil is maintained by binding it with tape. Therefore, the winding frame 3 has the role of preventing the coil from being deformed or coming apart from the beginning and end when the strip coil is stored, moved, incorporated into a mold, etc., and also to maintain the position of the coil within the mold. When the mold resin hardens, it tends to become a source of thermal stress due to the difference in expansion coefficient, and if delamination occurs between the mold resin and the mold resin, it becomes a source of partial discharge. There are drawbacks such as adverse effects on resin molded windings, and improvements are being sought from the standpoint of reducing insulation dimensions and cost reduction.

[Purpose of the invention]

The present invention was made in view of the above-mentioned situation, and
It is an object of the present invention to provide a method for winding a strip coil that can easily maintain shape stability and be miniaturized.

[Key points of the invention]

The present invention focuses on the fact that photocurable resins can be cured at room temperature by irradiation with ultraviolet light for a short period of time, for example, about one minute. By covering it with a reinforcing layer consisting of a body, the coil can maintain its shape even if the winding frame is removed.The winding method is structured so that the winding frame is formed of a transparent cylindrical body that transmits ultraviolet rays. As a result, it is now possible to easily form a reinforcing layer on the contact surface between the strip coil and the winding frame, which has conventionally been difficult to perform light irradiation treatment, in parallel with the step of winding the strip conductor.

[Embodiments of the invention]

The present invention will be explained below based on examples.

FIG. 1 is an explanatory diagram of an embodiment method of the present invention.
In the figure, 13 is a transparent cylindrical winding frame that is supported and rotated by a winding machine (not shown), and is made of a transparent material that transmits irradiation light including ultraviolet rays, such as a cylindrical acrylic resin or a glass cylinder. configured,
Spacers are interposed at key points in the circumferential direction to facilitate removal of the winding frame. Reference numeral 10 denotes a reinforcing layer consisting of a layered body of a transparent synthetic resin film 11 and a photocurable adhesive layer 12. For example, a polyester film coated with a liquid polyester ultraviolet curable resin is coated with a polyester film on the winding frame 13 side. The synthetic resin film 11 and the photocurable adhesive layer 1 are wound by winding the film a necessary number of times in close contact with each other so that the film is positioned in the desired position.
A layered body with 2 is formed. Reference numeral 1 denotes a strip coil tightly wound on the outside of a reinforcing layer 10, in which a thin strip conductor 4 made of aluminum, copper, etc. and an insulating sheet 5 made of polyester film, electrically insulating paper, etc. are wrapped around the strip conductor 4 on the inside. The strip conductors are arranged in layers and overlapped, and the strip conductors are wound a necessary number of times so that the first round of the strip conductor is in close contact with the photocurable adhesive layer 12 located on the outer peripheral surface of the layered body. Reference numeral 14 denotes an irradiation light source such as a high-pressure mercury lamp placed inside the cylindrical winding frame 13, and the irradiation light beam emitted from the irradiation light source 14 passes through the winding frame 13 and the synthetic resin film 11 to form a photocurable adhesive. By reaching the adhesive layer 12, the photocurable adhesive layer 12 can be cured in a very short time at room temperature, forming a reinforcing layer 10 that is thinner than the winding frame fixed to the innermost strip conductor. can do.
In addition, the timing of the light irradiation treatment may be any time after the first turn of the strip conductor has been wound, and if the irradiation treatment is performed in parallel with the winding work, it may be possible to Sufficient irradiation time can be secured without additional work time. After completing the winding work of the strip coil 1, the winding frame 1 is secured to prevent unwinding of the end of the winding.
3 is removed, but the reinforcing layer 10, which is fixed to the first turn of the strip conductor with an appropriate thickness, exhibits appropriate rigidity due to its complementary action with the strip conductor, and is useful for storing, transporting, molding the coil, etc. It functions effectively to prevent the coil from coming apart and maintain its shape in the same way as the winding frame, and when it is integrally molded in the molding resin, it functions as a part of the strip conductor, which is different from the conventional technology. Because it is thinner than a winding frame made of FRP, pressboard, etc., which is thick and strong enough to withstand winding work, resin mold winding is less likely to generate thermal stress or voids, and therefore has fewer weak points in terms of insulation. You can get the line.

FIG. 2 is an explanatory diagram showing a modification of the above-described embodiment, in which a reinforcing layer 20 fixed to the outer circumferential side of the strip coil 1
This is different from the previous embodiments in that the reinforcing layer 20 is photocured by the irradiation light source 14 disposed outside the strip coil, and the reinforcing layer 20 can be easily cured without considering obstacles such as frames. . The outer circumferential side of the strip coil configured as described above is bound tightly by the reinforcing layer 20, thereby making it possible to obtain a strip coil with better shape stability.

FIG. 3 is a sectional view of a strip coil showing a different modification of the above-mentioned embodiment, in which a reinforcing layer 3 is formed by applying a photo-curing resin to both sides of the coil 1 and photo-curing the resin.
This embodiment differs from the previous embodiment in that the reinforcing layer covers the entire surface of the strip coil, and the shape stability of the strip coil can be further strengthened.

Note that the photocurable adhesive is not limited to polyester-based ultraviolet curable resins, and may be selected from, for example, epoxy-based adhesives, visible light-curable adhesives, etc. as required. It is also possible to use a thermosetting photocurable resin; in this case, the reinforcing layer is photocured to provide shape stability, the winding frame is removed, and the entire coil is heated and post-cured. If a thermosetting photocurable resin is also applied between the strip conductor and the insulating sheet, a stronger strip coil can be formed by thermosetting.

〔Effect of the invention〕

As described above, the present invention includes a winding frame made of a transparent cylindrical body that transmits irradiation light, and a layered body of a transparent synthetic resin film and a photocurable adhesive on the outside of the winding frame, and a layered body of a photocurable adhesive. A strip conductor whose winding start portion is in close contact with the layer is wound with an insulating sheet interposed between the layers, and the photocuring adhesive layer is photocured using an irradiation light source placed inside the transparent winding frame, thereby fixing it to the strip conductor. The structure was such that a reinforced layer was formed.
As a result, a thin reinforcing layer whose rigidity is strengthened by being fixed to the strip conductor can be formed in a short time in parallel with the winding work on the inner circumferential side of the strip coil, which is difficult to photocure because it is obstructed by the winding frame. It is possible to provide a method for winding a strip coil that has excellent shape stability for storage, transportation, mold assembly, etc., and can prevent the coil from coming apart or deforming even after the winding frame is removed. When the strip coil is integrally molded in the molded resin, problems that impede the performance of resin-molded windings, such as thermal stress and partial discharge that occur in the winding frame in the conventional technology, are eliminated, and the reinforcing layer In addition to being thinner than the winding frame, it can contribute to the compact formation of resin molded windings with good performance.

[Brief explanation of drawings]

Fig. 1 is an explanatory diagram of an embodiment method of the present invention, Fig. 2 is an explanatory diagram showing a modification of the embodiment, Fig. 3 is a cross-sectional view of the main part showing a different modification of the embodiment, and Fig. 4 is a diagram illustrating a modification of the embodiment. FIG. 2 is a side sectional view showing an example of a conventional structure of a resin molded winding. 1, 1A, 1B, 1C... Strip coil, 2... Molding resin, 3, 13... Winding frame, 4... Strip conductor,
5... Insulating sheet, 10, 20, 30... Reinforcement layer, 11... Synthetic resin film, 12... Photo-curable adhesive layer, 13... Transparent winding frame, 14... Irradiation light source.

Claims (1)

[Claims] 1. A reinforcing layer consisting of a layered material of a transparent synthetic resin film and a photocurable adhesive closely formed on the inner circumferential surface of a coil formed by overlapping a thin strip conductor and an insulating sheet. A method for winding a strip coil in which the shape of the coil is maintained, the synthetic resin film being wound one or more times on the outer peripheral surface of a rotationally driven cylindrical transparent winding frame with the adhesive layer on the outside. After winding, a step of overlapping the strip conductor and an insulating sheet so that the strip conductor is in close contact with the adhesive layer, and a step of wrapping the strip conductor inside the winding frame after the strip conductor has been wound one or more turns. A method for winding a strip coil, comprising the step of photo-curing an adhesive layer of a reinforcing layer on the inner circumferential side of the strip coil while rotating the winding frame using an irradiation light source disposed in the coil. 2. In the method described in claim 1,
A method for winding a strip coil, characterized in that the winding frame is removed after the winding process is completed.