JPS63220735A - Flat coil - Google Patents

Abstract

PURPOSE:To secure a mechanical strength of apparatus and a connection reliability of derivation terminals by providing the inner peripheral part of a laminated body with a reinforcing plate to be connected with conductive foils. CONSTITUTION:In a flat coil 1, a wound body of conductive foils wound and laminated via insulating films, until desired characteristics may be obtained, is used as a coil part 2, and derivation terminals 3, 4 forming external connections are respectively fitted to the end of said wound body on its inner peripheral side and to the outermost peripheral face thereof. The inner peripheral face of said coil part 2 is reinforced by a reinforcing plate 5. In this manner, the mechanical strength of said flat coil 1 is improved. Also, said derivation terminal 3 fitted to the reinforcing plate 5 is connected securely to increase its fitting strength.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a flat coil used in motors, deflection yokes, transformers, etc.

[Summary of the invention]

The present invention provides a flat coil formed by winding a laminate of an insulating layer and a conductive foil and cutting it to a predetermined thickness, and by reinforcing the inner circumference of the flat coil with a reinforcing plate connected to the conductive foil. The joint strength of the lead-out terminal connected to the reinforcing plate is improved and is also good.

The purpose is to ensure the winding state, improve the cutting speed, and prevent the laminate from breaking, especially at the inner peripheral portion.

[Conventional technology]

Conventionally, motor coils and cathode ray tube deflection yokes have
Wire-wound coils made of many layers of w4&il are generally used, but as devices become smaller, thinner so-called flat coils have been developed and put into practical use.

For example, sheet coils for flat motors are made by etching a copper foil laminated to an insulating sheet in a spiral shape with a line width of about 50 μm.This is used to make the motor thinner and smaller. He has contributed greatly.

However, although the sheet coil described above is extremely useful for thinning, it is difficult to mass produce because it requires extremely high precision etching technology, and it requires special technology so it can be easily produced anywhere. There's no way I can do it.

Therefore, the idea of creating a wound body by winding a conductive foil coated with an insulating film and cutting it into rings to create a flat coil was proposed, and the applicant of the present application has proposed, for example,
No. 132,513 proposed a method of cutting the above-mentioned wound body by electric discharge machining to efficiently produce a highly reliable coil without causing short circuits or the like.

[Problem that the invention seeks to solve]

By the way, as a result of further study by the present inventors, it has been found that when manufacturing such a flant coil, when connecting a conductor bar serving as a lead-out terminal to a laminate made of a conductor foil and an insulating film, it is necessary to use an extremely thin conductor foil. When using a laminate, distortion occurs in the laminate at this connection part, and when the laminate is wound to create a wound body, wrinkles and meandering occur in the laminate, resulting in defects such as poor adhesion. It turned out that there was a risk. Similarly, when attempting to cut the above-mentioned wound body using the electric discharge machining method, especially when extremely thin conductor foil is used, the strength of the conductor foil at the inner circumference of the coil is insufficient, causing so-called curling, which slows down the cutting speed. Or, the conductor foil on the inner circumference is carelessly cut, resulting in a disconnection, resulting in a defective coil.Alternatively, the connection strength of the conductor rod is weak, and the lead-out terminal made of the conductor rod falls off. It has also been found that there is a possibility that this may occur.

In addition, when looking at the flat coil after it has been cut, there are problems such as deformation due to cutting and insufficient strength of the lead-out terminal portion, which makes it easy for the lead-out terminal to fall off during handling of the flat coil. I had left it behind.

Therefore, the present invention has been proposed in view of the above-mentioned problems, and has excellent mechanical strength and even higher reliability, and is also suitable even when the conductor foil strength is insufficient during manufacturing. The purpose of the present invention is to provide a flat coil that can be easily wound and cut, has a fast cutting speed, and is advantageous in terms of productivity.

[Means for solving problems]

In order to solve the above-mentioned problems and achieve the above-mentioned objects, a flat coil according to the present invention is a flat coil formed by cutting a wound body formed by winding a laminate of an insulating film and a conductive foil into a predetermined thickness. The present invention is characterized in that a reinforcing plate connected to the conductor foil is provided at the innermost circumferential portion when the laminate is wound.

[Effect]

In the flat coil according to the present invention, by providing a reinforcing plate connected to the conductor foil on the inner periphery, this reinforcing plate plays the role of an inner periphery reinforcing shaft, ensuring mechanical strength, and the above-mentioned Connection reliability of the lead-out terminal connected to the reinforcing plate is also ensured.

In addition, the formation of the reinforcing plate is advantageous when manufacturing a flat coil, and prevents distortion of the winding start part of the conductor foil to ensure good winding. By increasing the strength of the inner circumferential portion of the wound body, processing conditions can be strengthened, and cutting speed can be improved. Furthermore, the reinforcing plate protects the conductor foil on the inner periphery, and it becomes possible to cut a wound body using extremely thin conductor foil, which was difficult to cut in the past.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, the flat coil 1 according to the present invention has a coil portion 2 which is a wound body of conductive foil that is laminated and wound through an insulating film until desired characteristics are obtained. Lead-out terminals 3.4, which serve as external connection parts, are attached to the circumferential end and the outermost circumferential surface, respectively.

A metal foil made of a conductive metal material such as i+i foil is used as the conductive foil constituting the coil portion 2, and an adhesive layer is laminated thereon as an insulating layer between the eyebrows.

Therefore, the above body is in the form of a rolled laminate of a conductive foil and an insulating layer. The insulating film may be formed by forming the adhesive layer on one or both sides of the conductive foil, or by laminating a polymer film such as a polyimide film to ensure insulation. Two adhesive layers may be formed with the two adhesive layers sandwiched therebetween.

The inner peripheral surface of the coil portion 2 is reinforced by a reinforcing plate 5. The reinforcing plate 5 is made of a conductor plate whose material and thickness are determined to have higher mechanical strength than the conductor foil, and is wound together with the conductor foil at the beginning of the winding of the conductor foil. . Examples of the material of the reinforcing plate 5 include copper,
Brass, phosphor bronze, etc. are used, and the thickness is 50I! m~10
Approximately 0 μm is appropriate. The length of the reinforcing plate is such that it extends at least once around the inner circumferential surface of the coil portion 2 together with the conductive foil.

The lead-out terminals 3.4 of the flat coil 1 are each
For example, a bar-shaped conductive metal such as copper or brass is attached to the reinforcing plate 5 and the winding end position of the conductive foil, that is, the outer circumferential surface of the coil portion 2 by soldering or the like, and the flat coil 1 By soldering these lead-out terminals 3 and 4 to predetermined terminal portions during mounting, it is possible to achieve electrical continuity as well as mechanical connection. Although the shape of the lead-out terminal 3.4 is a columnar shape with a circular cross section in FIG. 1, it is not limited to this, and can be changed as appropriate, for example, to a square cross section, a semicircular cross section, etc. In addition, the lead-out terminal 3
．． 4 is also located at the reinforcing plate 5 and the coil portion 2, respectively.
Any outer circumferential surface may be used, and for example, the shape and position shown in FIG. 2 may be adopted. In FIG. 2, each of the lead-out terminals 3.4 has a rectangular cross section and is attached to the inner surface of the reinforcing plate 5 and the flat portion of the coil portion 2, so that the lead-out terminals 3.4 are The joint area of each of the reinforcing plate 5 and the coil portion 2 is large.

The flat coil 1 having such a configuration has improved mechanical strength due to the reinforcing plate 5, and is strong against deformation and the like. Further, the connection state of the lead-out terminal 3 attached to the reinforcing plate 5 is ensured, and the strength of the attachment is increased.

Next, a method for manufacturing the above-mentioned flat coil will be explained.

To manufacture the flat coil I, first, as shown in FIG. 3, an adhesive layer serving as an insulating layer is laminated onto the conductive foil 6. In this example, in order to ensure insulation, a polymer film 7 such as a polyimide film was laminated, and two adhesive layers 8.9 were coated with this film sandwiched therebetween. Here, the conductor foil 6 is a copper foil with a thickness of about 35 μm, and the adhesive layers 8 and 9 each have a thickness of 6 μm.
The polymer film 7 has a thickness of about 13 μm.
A polyimide film having a thickness of about 100 mm is used, but the present invention is not limited to this, and the thickness of each film may be set as appropriate.

Note that the polymer film 7 is not necessarily necessary.
For example, as shown in FIG. 4, both sides of the conductor foil 6 may be coated with the adhesive layer 8.9, or the adhesive layer may be applied only on one side.

The polymer film 7 or the adhesive layer 8.9 is laminated onto the conductor foil 6 using a device as shown in FIG. Glue 1f1'! ! ! The cloth is guided to the cloth machine 11, and adhesive is applied to both sides thereof. Next, dryer 12
The conductor M6 supplied from the unwinding roll 14 is bonded to this by the laminator 13, and wound onto the winding roll 15.

Through the above steps, as shown in FIG. 6, a raw roll of a laminate 16 consisting of the conductor foil 6, the polymer film 7, and the adhesive layers 8 and 9 is obtained.

Next, one surface of the conductor reinforcing plate 5 is adhered to one end of the laminate 16. The bonding position is a position where the reinforcing plate 5 is set back from the end 17 of the laminate 16, as shown in FIGS. 7a and 7S, or conversely, as shown in FIG. 7C. ,
The reinforcing plate 5 may be placed in a position protruding from the end 17 of the laminate 16. The material and thickness of the reinforcing plate 5 are determined to have higher mechanical strength than the conductive foil 6. The material used is, for example, copper, brass, phosphor bronze, etc., and the thickness is suitably about 50 μm to 100 μm. The length of the reinforcing plate 5 is approximately the same as the width of the laminate 16 in the direction perpendicular to the winding direction of the laminate 16 (arrow X direction in the figure), and the width is the same as the width of the laminate 16. Laminated body 16
the above laminate 1 in the same direction (direction of arrow Y in the figure).
The circumferential length of the innermost circumferential portion when the coil 6 is wound is approximately the same as or longer than the circumferential length of the innermost circumferential portion. An adhesive layer 18 is provided on the other surface of the reinforcing plate 5 so that the reinforcing plate 5 and other parts of the laminate 16 are bonded together during winding.

Next, as shown in FIGS. 8A to 8C, a metal rod 19 made of copper, brass, etc., for example, is soldered to the reinforcing plate 5 and the conductor foil 6 of the laminate 16 using solder 20. As shown in FIG. 8a, the metal rod 19 is placed on the end of the laminate 16 and adjacent to the side of the reinforcement 15, and the metal rod 19 is soldered with the solder 20. Either soldering to both the conductive foil 6 and the reinforcing plate 5, or
Alternatively, as shown in FIG. 7, the metal rod 19 is placed on the end of the reinforcing plate 5 and the conductor fi
6 and the reinforcing plate 5, or alternatively, as shown in FIG. 8C, the metal rod 19 can be soldered to the reinforcing plate 5! ! The conductor foil 6 and the reinforcing plate 5 may be soldered separately to the reinforcing plate 5 with the solder 20.As described above, the reinforcing plate 5 and the end There are some differences depending on the positional relationship of the portions 17, but in any case, the reinforcing plate 5 near the end portion 17
and the above-mentioned conductor foil 6 so as to be electrically connected to both.

Next, as shown in FIG. 9, the laminate 16 is wound around a central shaft 22 having a groove 21 that matches the shape of the metal rod 19. At this time, the reinforcing plate 5 is wound together with the laminate 16 at the winding start portion of the laminate 16, thereby forming an inner peripheral reinforcing shaft.

When winding, as shown in FIG.
The raw fabric roll No. 6 is sent out from the roll 23 and wound around the central shaft 22 having a substantially triangular cross section while applying back tension by the Tensilon roll 24 to obtain the wound body 25 of the laminate 16.

In this embodiment, when winding the laminated body 16 around the central shaft 22, a hot roll 27 energized by an air cylinder 26 is pressed from three sides to adjust the winding shape of the rolled body 25. Also, at this point, the adhesive layers 8, 9.1 of each layer of the laminate 16 are bonded by the hot roll 27.
The adhesive layer 8, 9.1 is between the conductive foils 6 to which 8 is attached.
8. In the flat coil according to the present invention, since the reinforcing plate 5 reinforces the innermost peripheral part of the laminate I6, the central axis 22 is no longer necessary at this point, and therefore, the central axis 22 is no longer necessary here. The above central axis 22
If it is removed from the wound body 25, it will be easier to cut it in the cutting process described later. The external shape of the obtained wound body 25 with the central axis 22 removed is shown in the 11th
As shown in the figure.

The cross-sectional shape of the central shaft 22 may be changed depending on the shape of the desired coil, and may be circular or oval.

It can have various shapes such as a quadrangle and a polygon.

Next, a solder rod 28 is connected along the end of the winding of the laminated body 16, that is, the end of the winding body 25, so that it becomes the other lead electrode when the winding body 25 is cut into individual coils. Make it.

This solder rod 28 is inserted into a nozzle 29 as shown in FIG.
It is easily formed by extruding solder in a softer state.

FIG. 13 is an external perspective view showing a state in which the solder rod 28 is connected to the wound body 25, and in this state, the laminated body 1
6 winding body 25. Reinforcement plate 5. All the components of the coil are now assembled, including the metal rod 19 that will serve as one electrode of the coil and the solder rod 28 that will serve as the other electrode. Therefore, these are collectively referred to as a coil block 30.

The coil block 30 obtained in the above process is heated at a predetermined temperature to completely cure the adhesive layers 8, 9 and 18 interposed between each layer of the wound body 25, and then As shown in FIG. 14, the coil block 30 is cut at predetermined intervals by electrical discharge machining.

The electric discharge machining method described above is a non-contact machining method that utilizes pulsed spark discharges at minute intervals in a dielectric liquid, which is also a coolant, and the associated short arc discharges. It can also be called consumption, and it can also be called an energy processing method. This electrical discharge machining method is usually used for processing conductors, such as forming molds, but it also shows good results when cutting laminates of metal foil and insulating layers.

To perform the electric discharge machining, the coil block 30 is immersed in the machining fluid 31, and pulsed power is applied from the plate electrodes 32 arranged at predetermined intervals in the longitudinal direction of the wound body 25. Furthermore, water or a petroleum-based machining fluid such as kerosene can be used as the machining fluid during electrical discharge machining.

The coil blocks 30 do not necessarily need to be cut one by one; a plurality of the coil blocks 30 are arranged in parallel, and these are simultaneously connected to plate-shaped electrodes 3 arranged at predetermined intervals.
It may be cut at 2.

When performing the electrical discharge machining, it is necessary to provide ground on the coil block 30 side. Therefore, a method for establishing this grounding is illustrated in FIG. 15. In this example, the coil block 30 is placed on a fixture 33 made of conductive gold i, and the fixture 33 is grounded.

By the electric discharge machining method described above, the coil block 30 is cut into flat coils having a predetermined thickness, as shown in FIG.

Here, in order to confirm the manufacturing effect of the reinforcing plate 5, the inventor actually manufactured a flat coil under the conditions described below.

Copper foil with a thickness of 25 μm was used as the conductor fI6, phosphor bronze with a thickness of 80 μm was used as the reinforcing plate 5, and the thickness of the adhesive layer 8 was 5 μm. The above polymer film 7
The above-mentioned coil block 30 was created by the above-mentioned process using these materials, and cut by electrical discharge machining. For comparison, a sample without the reinforcing plate 5 was made using the same process and cut using the electrical discharge machining method. When the yield was examined by changing the cutting speed, the results shown in the table below were obtained.

The numerical values in the table are the ratio of non-defective products to the cut flant coils, that is, the yield. Defects that occur during cutting include breakage of the conductor foil and accompanying detachment of the lead-out terminal.

As is clear from the table, the yield of conventional flat coils that do not use reinforcing plates decreases rapidly when the cutting speed is increased, but the flat coil that uses reinforcing plates according to the present invention has Even when the speed was increased, there was almost no decrease in yield, and a high yield of 95% was obtained.

Although specific embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and shapes and materials may be changed without departing from the gist of the present invention.

Dimensions etc. may be changed. Furthermore, the manufacturing method is not limited to the above-mentioned method, and for example, the cutting method may be a mechanical cutting method, a laser cutting method, or the like.

〔Effect of the invention〕

As described above, in the flat coil according to the present invention, the inner peripheral portion is reinforced by the reinforcing plate connected to the conductor foil, so that the mechanical strength is improved and the bonding strength of the lead-out terminal is improved. is possible.

Furthermore, reinforcing the inner periphery of the laminate with the reinforcing plate is advantageous during winding and cutting during manufacturing, ensuring a good winding state and improving cutting speed. Breaking of the laminate at the periphery and deformation of the wound body are prevented, and a flat coil with excellent productivity and reliability can be provided.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing one embodiment of a flat coil to which the present invention is applied, and FIG. 2 is a perspective view showing another embodiment of the flat coil to which the present invention is applied. 3 to 16 show an example of a method for manufacturing a flat coil to which the present invention is applied in accordance with the process order. FIG. 5 is a schematic diagram showing the step of forming an insulating layer on a conductor foil; FIG. 6 is a perspective view of the appearance of a raw coil with an insulating layer attached; Figures 7a to 7C are schematic perspective views of the main parts showing the state of attachment of the reinforcing plate to the laminate, and Figures 81 to 8C are the metal rods attached to the reinforcing plate, respectively. 9 is an enlarged cross-sectional view of the main part showing the mounting state of
Figure 1 () is a schematic diagram showing the process of winding around the central axis, Figure 11 is an external perspective view of the wound body wound around the central axis,
Fig. 12 is an external perspective view showing the process of connecting solder rods that become electrodes, Fig. 13 is an external perspective view of the coil block, Fig. 14 is a schematic side view showing the cutting process by electrical discharge machining, and Fig. 15 16 is a schematic diagram showing a method of connecting the ground to the coil block, and FIG. 16 is an external perspective view showing the coil block after being cut. 1・・・・・・・・・・Flat coil 5・・・・
......Reinforcement plate 6...Conductor foil 7...Polymer film 8.9...
...Adhesive layer 16 ...... Laminate patent applicant Sony Chemical Co., Ltd. Representative Patent attorney Mimi Koike 1) Shiba Mura - Figure 2 Figure 3 Figure 4 Figure H Figure 5! 5 Figure 6 lσ Figure 9 Figure 12 Figure 13 Button Figure 14 Figure 15 hP Figure 16

Claims (1)

[Claims] In a flat coil formed by winding and cutting a laminate of an insulating layer and a conductive foil to a predetermined thickness, the laminate is connected to the conductor foil at the innermost circumference when the laminate is wound. A flat coil characterized by being equipped with a reinforcing plate.