JPH0927436A - Electric component with built-in-coil and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric component with a built-in-coil which enables an extremely fine coating lead wire of a compact coil to be connected to an external wiring cable, etc., readily. SOLUTION: A compact coil 51 whereon an extremely fine coating lead wire 57 is wound is buried in an electric insulating resin block 50 in a state that an edge face thereof is along a surface of the resin block 50. A part of terminals 57a, 57b of the coating lead wire 57 are cut out together with a part of the resin block 50 by cutting out a surface side of the resin block 50 and a conductor part of the terminals 57a, 57b is exposed in a surface of the resin block 50. Furthermore, conductive layers 60, 61 are formed along a surface of the resin block 50 by a film formation means such as deposition or print and the terminals 57a, 57b of the coating lead wire 57 are connected to the conductive layers 60, 61.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil built-in electric component applied to a sensor or a small actuator having a small electromagnetic coil and a manufacturing method thereof.

[0002]

2. Description of the Related Art With the progress of miniaturization and integration of electronic devices, the use of small coils using ultrafine coated conductor wires having a wire diameter of 50 μm or less is increasing. For example, conventionally, a coated motor having a diameter of about 18 to 20 μm has been used in a wristwatch motor, and a coated motor having a diameter of about 20 μm has been used in a small-sized communication mechanical relay. Also, a sensor is being developed in which it is desired to integrate a large number of small electromagnetic coils in the same plane.

[0003]

Since a small coil using the ultrafine conductor wire as described above is generally difficult to connect to a terminal of a device, a substrate, etc., the device side has a shape that facilitates soldering or spot welding. There is no choice but to take measures such as devising. Therefore, an electric component with a built-in coil using an ultrafine conductor has a problem that the shape and size of the device are largely restricted due to the connection.

Particularly, it is said that it is extremely difficult to connect an ultrafine coated conductor wire having a wire diameter of less than 30 μm. The reason is that not only the conductor itself is easily cut, but also it is difficult to cleanly remove the coating of the conductor end without damaging the conductor of the coated conductor, and moreover, equipment for connection such as soldering irons and spot welders. This is because the shape and the like are also greatly restricted.

Further, in a sensor using a small coil having an outer diameter of about 2 mm or less, if the fine conductor wire as described above is used as the conductor wire for connection with the coil, the electric resistance becomes too large. Therefore, the ultrafine conductor used for the coil cannot be used as it is as a conductor for wiring. On the other hand, it is often practically difficult to connect a thick wiring conductor having a small electric resistance to the ultrafine conductor of the coil in a limited space near the coil.

Therefore, an object of the present invention is to provide an electric component with a built-in coil, which is easy to connect the ultra-fine conductor wire of the coil to an external wiring cable, etc., in a small electric component with a built-in coil using an ultra-fine coated conductor wire, and a manufacturing method thereof. To provide.

[0007]

SUMMARY OF THE INVENTION The coil built-in electric component of the present invention, which has been developed to achieve the above object, comprises a resin block made of an electrically insulating synthetic resin and an ultrafine coated wire having a wire diameter of 50 μm or less. A coil which is a turned small coil, the end face of which is embedded in the resin block in a posture along the surface of the resin block, and the conductor portion of the end of the coated conductor is made to face the surface of the resin block, A conductive layer is applied along the surface of the resin block by a film forming means such as plating, vapor deposition, or printing, and a conductive layer electrically connecting the conductor portions of the terminals of the coated conductor is provided.

In the method for manufacturing an electric component with a built-in coil according to the present invention, a small coil formed by molding a resin block made of an electrically insulating synthetic resin and wound with an ultrafine coated wire having a wire diameter of 50 μm or less has an end surface of the resin. A coil embedding step of embedding so as to be in a posture along the surface of the block, a terminal treatment step of exposing the conductor part of the end of the coated wire of the coil to the surface of the resin block, and a conductive layer along the surface of the resin block. And a conductive layer forming step of connecting the conductive portion of the end of the coated conductive wire of the coil to the conductive layer while applying the film by a film forming means such as plating, vapor deposition or printing.

In the coil embedding step, molten resin is injected into the mold in a state where the coil is housed in a mold for molding a resin block, and the resin is cured to mold the coil into the resin, or a predetermined process is performed in advance. The coil may be fixed by forming a hole in a predetermined position of the resin block formed into a shape by machining or the like, housing the coil in this hole, and then filling the hole with resin.

In the terminal treatment step, the surface side of the resin block is machined together with a part of the end of the coated conductor of the coil to expose the conductor portion of the end of the coated conductor to the surface of the resin block. . Alternatively, in the coil embedding step, the coil having the masking material attached to the end of the coated conductor is embedded in the resin block, and then the masking material and the coating portion of the end of the coated conductor are simultaneously removed by the solvent in the terminal exposing step. You may

In the conductive layer forming step, a conductive material having a predetermined pattern is formed by depositing a conductive substance on the surface of the resin block by printing, or the resin block is formed by a film forming means such as plating, vapor deposition or sputtering. After forming a layer of a conductive substance on the surface of, the unnecessary portion may be removed by etching to form a conductive layer having a predetermined pattern.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIGS. The workpiece measuring sensor unit 11 shown in FIG. 5 is a plurality of the contact displacement sensors 12 shown in FIG. 6 arranged in parallel along the workpiece to be measured. The displacement sensor 12 includes a cap plate 15, a top guide plate 16, a first detection coil plate 17, an excitation coil plate 18, and a second detection coil plate 1 in this order from the top in the drawing.
9 and the lower surface side guide plate 20, and a plunger 21 movable in the vertical direction. The coil plates 17, 18, and 19 are examples of the coil-embedded electrical components referred to in this specification, and have substantially the same configuration.

The plunger 21 includes a long and thin pipe 30 made of a non-magnetic electrically insulating material or a metal having a low magnetic permeability such as stainless steel, a contactor 31 inserted into the tip of the pipe 30, and a pipe 30. A rear end member 32 attached to the rear end portion, a rod-shaped core 33 housed inside the pipe 30, and the like are provided. The core 33 is fixed to the inner surface of the pipe 30.

A spring 37 for urging the plunger 21 downward is housed in a recess 35 formed inside the cap plate 15. In addition, the convex portion 3 is formed on the rear end member 32.
8 is provided, and the convex portion 38 is used as the guide plate 1.
The position of the descending end of the plunger 21 can be regulated by abutting against 6. A plurality of guide holes 41 are formed in the upper guide plate 16, and the plunger 21 is inserted into these guide holes 41 so as to be movable in the axial direction. Further, positioning guide pins 42 are provided on the guide plate 16.

The first detection coil plate 17, which is an example of a coil built-in electric component, includes a flat resin block 50 made of an electrically insulating synthetic resin, and a first detection coil 51 embedded in the resin block 50. Is equipped with. First
The detection coil 51 is provided at a position corresponding to the guide hole 41, and as shown in FIG. 1, the end surfaces 52 and 53 of the coil 51 are embedded in the resin block 50 in such a manner that the end surfaces 52 and 53 are along the front surface and the back surface of the resin block 50. Has been done.

The coil 51 is a cylindrical bobbin 56 wound with an ultra-fine coated wire 57 having a wire diameter of 50 μm or less (for example, about 20 μm) wound a predetermined number of times and having an outer diameter of 2 m.
It is a small coil of m or less. The terminals 57a and 57b of the coated conductor 57 are exposed to the front and back surfaces of the resin block 50.

Along the front and back surfaces of the resin block 50, a conductive layer 60 made of a conductive material such as gold, silver or copper,
61 is applied. The conductive layers 60 and 61 are formed in a predetermined pattern on the resin block 50 by a film forming means described later. And this conductive layer 6
The conductors of the terminals 57a and 57b of the covered conductor 57 are electrically connected to the conductors 0 and 61.

The detection coil plate 17 is manufactured through a coil embedding step, a terminal treatment step, and a conductive layer forming step, as will be described below as an example. First, in the coil embedding step, as shown in FIG. 3, the coil 51 is embedded in the resin block 50 with both end surfaces 52 and 53 of the coil 51 along the front and back surfaces of the block 50. As a method of embedding the coil 51 in the resin block 50, for example, the following resin molding method is adopted.

In the resin molding method referred to here, the coil 51, in which the covered conductor 57 is wound around the bobbin 56 in advance, is housed at a predetermined position inside the mold for molding the resin block 50, and the material of the block 50 is used. Is a method of burying the coil 51 in the resin block 50 as shown in FIG. 3 by pouring the molten resin into the mold and curing the resin. In this case, the terminals 57a, 5 of the covered conductor 57 are
7b is projected from the end surfaces 52 and 53 of the coil 51. Further, the spacer 62 is inserted inside the bobbin 56.

In the coil embedding step, as a method other than resin molding, for example, a hole is drilled at a predetermined position of the resin block 50 which is molded in a predetermined shape in advance, and the coil 51 is inserted in the hole in the same manner as described above. After assembling the coil 5 into a posture, by filling a resin such as an adhesive between the inner surface of this hole and the coil 51, the coil 5
1 may be fixed.

After the coil 51 is embedded in the resin block 50 in the coil embedding step described above, the front surface side and the back surface side of the resin block 50 are scraped off by machining in the terminal treatment step to form a part of the resin block 50. A part of the terminals 57a and 57b of the coated conductor 57 is scraped off together. By doing so, as shown in FIG. 4, the resin block 50 having the predetermined plate thickness t is formed, and the conductor portions of the terminals 57a and 57b of the conductor 57 are formed on the resin block 5.
It is exposed on both front and back sides of 0.

After that, in the conductive layer forming step, the conductive layer 6 is formed on the front and back surfaces of the resin block 50 as shown in FIG.
0 and 61 are formed, and the terminals 57a of the lead wire 57,
57b and the conductive layers 60 and 61 are electrically connected. Here, as a method of forming the conductive layers 60 and 61, for example, a conductive substance is applied to the front surface and the back surface of the resin block 50 by printing to form the conductive layers 60 and 61 having a predetermined pattern.
To form

Alternatively, the resin block 50 is formed by a film forming means selected from plating, vapor deposition and sputtering.
After forming a layer of a conductive material on the front and back surfaces of the substrate, unnecessary portions are removed by etching to form a conductive layer 6 having a predetermined pattern.
You may make it leave 0 and 61.

In the case of the above embodiment, the spacer 62 inside the bobbin 56 is removed to make the coil 51 an air core, and both ends of the coil 51 are opened on both front and back surfaces of the resin block 50, so that the coil 51 is plungerd. 21
To be able to pass through.

The detection coil plate 17 manufactured through the above manufacturing process has conductive layers 60, 6 as shown in FIG.
1 along the front and back surfaces of the resin block 50, and the end portions 60a and 61a of the conductive layers 60 and 61 are formed.
Can be connected to the wiring cable 65 by a suitable connecting means such as soldering or spot welding in a space near the edge of the resin block 50 with a space.

On the other hand, the exciting coil plate 18 (see FIGS. 5 and 6) is provided with a flat plate-shaped resin block 70 made of electrically insulating synthetic resin and an exciting coil 71 embedded in the resin block 70. . This exciting coil plate 1
8 is also manufactured through the same steps as the coil plate 17 (coil embedding step, terminal treatment step, and conductive layer forming step), and conductive layers 72 and 73 are formed along the front and back surfaces of the resin block 70 as shown in FIG. It is arranged. Excitation coil 7
1 is also an air-core coil with both ends open, and the end surface of the coil 71 is embedded in a posture along the surface of the resin block 70 so that the plunger 21 can be passed through the coil 71.

The second detection coil plate 19 is a flat resin block 80 made of electrically insulating synthetic resin.
And the second detection coil 8 embedded in the resin block 80.
1 is provided. This second detection coil plate 19
Is also manufactured through the same steps as the first detection coil plate 17 (coil embedding step, terminal treatment step, and conductive layer forming step), and as shown in FIG. 82.83 are provided. The second detection coil 81 is also an air-core coil whose both ends are open, and the end surface of the coil 81 is embedded in a posture along the surface of the resin block 80 so that the plunger 21 can be passed through the coil 81. There is.

When the conductive layers 61, 72, 73, 82 may come into contact with each other when the coil plates 17, 18, 19 are stacked, the coil plates 17, 18, 19 are prevented in order to prevent short circuit between them. Insulating sheets 85 and 86 made of an electrically insulating material may be sandwiched between them. The guide plate 20 on the lower surface side also has a flat plate shape, and a guide hole 88 through which the plunger 21 is inserted is formed.

As shown in FIG. 5, through holes 90 to 96 for passing the guide pins 42 are formed in the plates 16 to 20 and the insulating sheets 85 and 86, and the guide pins 42 are inserted into the through holes 90 to 96. Each plate 16-2 by passing
The mutual positioning of the coils is performed so that the plunger 21 passes through the centers of the coils 51, 71, 81.

Each plate 15 constructed as described above,
16, 17, 18, 19, 20 and insulating sheets 85, 86
Are stacked in the thickness direction, and the plates 15 to 20 are fixed to each other by an appropriate fixing means such as adhesion or bolting. Since the plates 15 to 20 are all flat plates, they can be firmly fixed to each other by adhesion, bolting, or the like, positioning of the plates is easy, and the rigidity of the sensor unit 11 as a whole is high. Sufficient mechanical strength is also obtained.

The coils 51, 71 and 81 and the plunger 21 constitute a three-stage differential transformer. In this case, when a primary AC voltage is applied to the exciting coil 71, the generated magnetic flux interlinks with the detecting coils 51 and 81.
The difference between the electromotive forces generated at 1, 81 can be taken out as the secondary voltage. This secondary voltage is substantially zero when the position of the core 33 is at the neutral point with respect to the detection coils 51 and 81, but when the core 33 is displaced from the neutral point, the secondary voltage of the secondary voltage is changed according to the displacement amount. It shows a linear output characteristic such as a large value. Therefore, by previously obtaining the relationship between the secondary voltage and the displacement amount of the core 33, the position of the core 33, that is, the displacement amount of the plunger 21 can be known based on the detected secondary voltage.

In order to process the detection signal of the differential transformer (differential pressure between the detection coils 51 and 81), an arithmetic processing unit (not shown) using a microcomputer or the like is provided for the coils 51 and 71 of the sensor unit 11. , 81. Wiring for each coil 51, 71, 81 is performed using the wiring cable 65 via the above-mentioned conductive layers 60, 61, 72, 73, 82, 83.

Although each of the above-described embodiments is an example in which the present invention is applied to a sensor, the present invention can be applied to a coil built-in electronic device such as an actuator (electromagnetic solenoid) in which coils of the same form are integrated. Also in this case, for the same reason as described above, electrical connection to the ultrafine conductor of the small coil is facilitated, and the device can be downsized and the coil can be highly integrated.

Needless to say, in carrying out the present invention, the resin block, the coil, the conductive layer and the like can be modified in various ways. For example, as shown in FIG. 7, a yoke 101 made of a magnetic material may be provided inside the bobbin 56 according to required specifications. The other configurations and manufacturing methods are similar to those of the coil 51 of the above-described embodiment, and therefore, the same parts as those of the above-mentioned embodiment are designated by the same reference numerals and the description thereof will be omitted.

Further, as shown in FIG. 8, the resin block 5
The conductive layers 60 and 61 are formed on one surface side of 0, and the terminals 57a and 57b of the covered conductor 57 are formed on the conductive layers 60 and 61, respectively.
May be connected. The other configurations and manufacturing methods are similar to those of the coil 51 of the above-described embodiment, and therefore, the same parts as those of the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.

9 to 11 show another embodiment of the manufacturing process. In this case, in the coil embedding step, as shown in FIG.
A masking material 120 such as oil and fat is attached to the terminals 57a and 57b, the coil 51 is housed inside a mold for molding the resin block 50, and molten resin is injected into the mold to cure the resin. Alternatively, the coil 51 is fixed by making a hole in the preformed resin block 50, incorporating the coil 51 in this hole, and then filling the hole with resin.

After the coil 51 is embedded in the resin block 50 in this way, the masking material 1 is used in the terminal treatment step.
As shown in FIG. 10, the conductors of the terminals 57a and 57b are removed by removing the masking material 120 and the coating of the terminals 57a and 57b of the coated conductor 57 at the same time with a solvent capable of dissolving the insulating coating of the conductor 20 and the coated conductor 57. Are exposed on the surface of the resin block 50.

After that, as shown in FIG. 11, in the conductive layer forming step, the conductive layers 60 and 61 having a predetermined pattern are formed on the surface of the resin block 50 by printing, or the resin block is formed by plating, vapor deposition, sputtering or the like. After forming a film on the surface of 50, unnecessary portions are removed by etching to leave the conductive layers 60 and 61 having a predetermined pattern.

[0039]

According to the present invention, it becomes easy to connect a small coil using an ultra-fine coated wire to an external wiring cable, and it is possible to significantly alleviate the restriction of the device shape due to the connection. Further miniaturization of the coil built-in electric component can be achieved. Also, downsizing of equipment using this component can be achieved. Further, when it is necessary to arrange a large number of small coils in a narrow range, the degree of integration of the coils can be increased.

[Brief description of drawings]

FIG. 1 is a sectional view of a part of an electric component with a built-in coil showing an embodiment of the present invention.

FIG. 2 is a perspective view of the coil built-in electric component shown in FIG.

FIG. 3 is a cross-sectional view showing a state in which a coil is embedded in a resin block in the process of manufacturing the coil built-in electric component shown in FIG.

FIG. 4 is a cross-sectional view showing a state in which a part of the resin block is scraped off in the process of manufacturing the coil built-in electric component shown in FIG. 1.

5 is an exploded perspective view of a sensor using the electric component with a built-in coil shown in FIG.

6 is a cross-sectional view of a portion of the sensor shown in FIG.

FIG. 7 is a partial cross-sectional view of an electric component with a built-in coil showing another embodiment of the present invention.

FIG. 8 is a partial cross-sectional view of an electric component according to yet another embodiment of the present invention.

FIG. 9 is a cross-sectional view of a state in which a masking material is attached to the end of the lead wire in the process of manufacturing an electric component with a built-in coil.

FIG. 10 is a cross-sectional view showing a state in which the masking material is removed from the end of the conductive wire.

FIG. 11 is a sectional view showing a state in which a conductive layer is formed on a resin block.

[Explanation of symbols]

12 ... Displacement sensor 17, 18, 19 ... Coil plate (electrical component with built-in coil) 50 ... Resin block 51 ... Coil 57 ... Coated conductors 57a, 57b ... Terminals 60, 61 ... Conductive layer 70 ... Resin block 71 ... Coil 80 ... Resin Block 81 ... Coil 120 ... Masking material

Claims (8)

[Claims] 1. A small coil formed by winding a resin block made of an electrically insulating synthetic resin and an ultrafine coated conductor wire having a wire diameter of 50 μm or less, wherein the coil end surface is in the posture of being along the surface of the resin block. A coil in which the conductor portion of the end of the covered conductor is exposed to the surface of the resin block, and a conductive substance is applied along the surface of the resin block by a film forming means such as plating, vapor deposition or printing. An electric component with a built-in coil, comprising: a conductive layer that electrically connects the conductor portion of the end of the coated conductor. 2. A small coil formed by molding a resin block made of an electrically insulating synthetic resin and winding an ultrafine coated conductor wire having a wire diameter of 50 μm or less is embedded so that its end face is oriented along the surface of the resin block. A coil embedding step, a terminal treatment step of exposing the conductor portion of the end of the coated wire of the coil to the surface of the resin block, and a film forming means such as plating, vapor deposition or printing of a conductive layer along the surface of the resin block. And a conductive layer forming step of connecting the conductor portion of the end of the coated wire of the coil to the conductive layer, and a method of manufacturing an electric component with a built-in coil. 3. The coil embedding step is performed by injecting a molten resin into a mold in a state where the coil is accommodated at a predetermined position inside a mold for molding the resin block and curing the resin. The method for manufacturing an electric component with a built-in coil according to claim 2, wherein the resin is integrally molded in a resin. 4. In the coil embedding step, a hole is made in a predetermined position of the resin block which is molded in a predetermined shape in advance, the coil is housed in this hole, and then a resin is filled between the coil and the inner surface of the hole. The method for manufacturing an electric component with a built-in coil according to claim 2, wherein the coil is fixed by performing the above. 5. The terminal treatment step is carried out by machining the surface side of the resin block together with a part of the end of the coated conductor of the coil by machining so that the conductor portion of the end of the coated conductor is removed from the resin block. The method of manufacturing an electric component with a built-in coil according to claim 2, wherein the electric component is exposed on the surface. 6. In the coil embedding step, a coil having a masking material attached to the end of the coated conductor is embedded in the resin block, and then in the terminal treatment step, the masking material and the end of the coated conductor are separated by a solvent. The method for manufacturing an electric component with a built-in coil according to claim 2, wherein the conductor portion of the end of the coated conductor is exposed to the front surface side of the resin block by simultaneously removing the coating. 7. The electric component with a built-in coil according to claim 2, wherein in the conductive layer forming step, a conductive material having a predetermined pattern is formed by depositing a conductive material on the surface of the resin block by printing. Manufacturing method. 8. The conductive layer forming step forms a layer of a conductive material on the surface of the resin block by a film forming means selected from plating, vapor deposition and sputtering, and then removes unnecessary portions by etching. 3. The method for manufacturing an electric component with a built-in coil according to claim 2, wherein the conductive layer having a predetermined pattern is left.