JPH09102670A - Fixing method for metallic terminal plate to board and molding method for electronic component and board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for fixing a metallic plate to a board easily and a method for molding an electronic component without a bur of molding resin on the surface of the electronic component. SOLUTION: A conductive pattern of a flexible board 10 and a metallic terminal plate 39 of an electronic component 30 are joined with a hot melt-type conductive adhesive. In this state, the flexible board 10 is put between an upper mold 71 and a lower mold 73. The conductive pattern of the flexible board 10 and a joining part of the metallic terminal plate 39 are put firmly between pins 81 and 87 in cavities 75 and 77. When molten molding resin at high temperature under high pressure is injected from a pin gate 89, most of molding resin is spouted directly to a rear face of a main function body 31 through a through hole 19 while a surface 33 of the main function body 31 is fitted firmly to a fitting face 79. Then, the front surface 33 is protected from the molding resin. On the other hand, the conductive adhesive is melted by the heat of the melted resin, so the conductive pattern and the metallic terminal plate 39 are connected electrically at the joining part.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for fixing a metal terminal plate to a substrate and a method for molding an electronic component and a substrate.

[0002]

2. Description of the Related Art Conventionally, an electronic component such as a photosensor or a magnetoresistive element mounted on a support made of a molded resin is fixed on a flexible substrate, and the support mounted on the flexible substrate is further fixed to another fixing member. In such a case, the electronic component is placed facing another object to be detected (for example, near the surface of an optical disk) with a predetermined distance therebetween.

Here, once the electronic component is fixed to a support made of a molded resin and then fixed to the fixing member, the positional relationship such as the separation distance between the electronic component and the object to be detected is precisely fixed. This is because

By the way, there are the following methods for mounting a mold resin support and electronic components on a flexible substrate. A method in which electronic components are mounted on a preformed molded resin support, and the support is fixed to a flexible substrate using another metal fitting. At this time, the connection between the metal terminal plate protruding from the electronic component and the conductive pattern formed on the flexible substrate is performed by pressing the metal terminal plate against the conductive pattern with an elastic member attached to the support.

[0005] A metal terminal plate of an electronic component is fixed to the conductive pattern of the flexible substrate in advance using an adhesive or the like, and then the electronic component and the flexible substrate are sandwiched between upper and lower dies to surround the electronic component. A method of forming a support by molding a mold resin.

[0006]

However, the above-mentioned conventional example has the following problems. (1) In the case of the above conventional example, not only is the fixing work for fixing the support base to the flexible substrate complicated, but also an elastic member for pressing the metal terminal board of the electronic component against the conductive pattern of the flexible substrate is required. The number of parts increases, and cost reduction cannot be achieved.

(2) In the above conventional example, when the surface of the electronic component needs to be exposed like a photo sensor, the surface of the electronic component to be exposed is placed on the surface of the mold during molding resin molding. It must be kept in close contact, but the contact may not be made firmly. If the adhesion is not strong, the mold resin may enter between the surface to be exposed and the mold, and the surface may be covered with burrs of the mold resin, resulting in defective products.

Further, in the case of this conventional example, two steps of a step of previously fixing the metal terminal plate of the electronic component and the conductive pattern of the flexible substrate and a step of molding the mold resin are required, and the manufacturing steps are complicated. Met.

The present invention has been made in view of the above points, and an object of the present invention is to provide a method of fixing a metal terminal plate to a substrate, which can be easily and inexpensively manufactured.

It is another object of the present invention to provide a method of molding an electronic component and a substrate in which burrs due to a mold resin do not cover the surface of the electronic component.

[0011]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a substrate having a conductive pattern formed thereon, a metal terminal plate connected to the conductive pattern, and a connection between the conductive pattern and the metal terminal plate. Prepare upper and lower molds provided with cavities to cover the top and bottom of the part to be joined, and join the conductive pattern of the substrate and the metal terminal plate with a hot melt type conductive adhesive interposed, and in this state The substrate is clamped by the upper and lower molds, and at the time of the clamping, the joint between the conductive pattern and the metal terminal plate is clamped by pins provided in at least one of the cavities of the upper and lower molds. Injection molding a molten mold resin into the cavity of the mold, and melting the conductive adhesive by the heat of the molten mold resin, and simultaneously applying the pressure of the molten mold resin to the conductive pattern. By pressing the joint of the metal terminal plate and cooling in this state, the molten mold resin and the conductive adhesive are solidified to electrically and mechanically fix the joint of the conductive pattern and the metal terminal plate. Thus, a method for fixing the metal terminal plate to the substrate was configured. Further, the present invention provides an electronic component having a metal terminal plate protruding from a functional portion main body, a substrate provided with a conductive pattern for joining the metal terminal plate of the electronic component, and an upper and lower mold for holding the substrate from upper and lower surfaces thereof. And a through-hole is provided in a portion of the substrate located directly below the functional part main body of the electronic component, and the functional part main body is provided in a mold of the upper and lower molds on which the electronic component is located. A cavity having an abutting surface that abuts the surface of the electronic component, the electronic component and the substrate were sandwiched between upper and lower molds, and provided on the substrate of the upper and lower molds on the side where the electronic component was not located. A molten resin is injected from a pin gate provided at a position facing the through hole, and the molten resin is directly applied to the back surface of the functional unit main body through the through hole of the substrate so that the surface of the functional unit main body contacts the cavity. While pressing strongly against the surface, By filling the molten resin into the chromatography was constructed mold method of the electronic component and the substrate.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings. 2 and 3 are views showing a structure for fixing an electronic component to a flexible substrate manufactured by using the method according to the present invention, wherein FIG. 2 (a) is a plan view and FIG. 2 (b) is FIG. 3A is a sectional view taken along line AA, FIG. 3C is a sectional view taken along line BB in FIG. 3A, FIG. 3D is a rear view, and FIG. 3 is a sectional view taken along line CC in FIG. .

As shown in FIGS. 1 and 2, the electronic component fixing structure on the flexible substrate is configured by mounting an electronic component 30 on the upper surface of the flexible substrate 10 and molding the periphery of the electronic component 30 with a support base 50. Hereinafter, each component will be described.

FIG. 4 is a plan view showing the flexible substrate 10. As shown in FIG.
Is formed on a substrate 18 made of a flexible synthetic resin film (for example, PET film) by using a silver paste
It is configured by screen-printing three conductive patterns 11, 12, 13, 14 and three circuit patterns 15, 16, 17 made of silver paste drawn from the respective conductive patterns 11, 12, 13, 14. .

A circular through hole 19 is provided at the center of the four conductive patterns 11, 12, 13, 14 of the flexible substrate 10, and the two conductive patterns 11, 1
A circular through-hole 21 is also provided on the side of 2, and six through-holes 23 are provided around four conductive patterns 11, 12, 13, 14.

FIG. 5 is a view showing the electronic component 30.
FIG. 1A is a plan view, and FIG. 1B is a side view.

The electronic component 30 is a photo sensor,
Both a light emitting unit 35 and a light receiving unit 37 are provided on the surface 33 of the functional unit main body 31 made of mold resin. The electronic component 30 is used to irradiate, for example, light emitted from the light emitting unit 35 to a not-shown detection target (for example, the surface of an optical disk) and to receive the reflected light by the light receiving unit 37. Therefore, the distance between the surface 33 and the object to be detected must be accurately positioned.

Two metal terminal plates 39 protrude from both sides of the functional portion main body 31, respectively. Each of these metal terminal plates 39 is bent at a right angle at two places on the way, so that when the metal terminal plate 39 is mounted on the flexible substrate 10,
1 is located at a position higher than the flexible substrate 10 by a predetermined height.

Next, returning to FIG. 2, the support base 50 is configured such that the support base upper part 51 and the support base lower part 53 provided on the upper and lower surfaces of the flexible substrate 10
3 and are formed integrally through the through hole 19.

Here, the support base upper part 51 has a substantially rectangular shape.
It is formed so that the entire periphery thereof is molded with the surface 33 of the electronic component 30 on the flexible substrate 10 exposed.

Two circular holes 55 are formed in each portion of the electronic component 30 where the metal terminal plate 39 is located.

Also, three rectangular holes 57 are formed at the left and right roots of the electronic component 30 where the metal terminal plate 39 protrudes from the functional portion main body 31.

Here, the hole 55 is formed because a movable pin 81 described below for sandwiching the metal terminal plate 39 and the flexible substrate 10 is inserted when the support base 50 is formed. 57 is a guide pin 83 for positioning the metal terminal plate 39 when the support base 50 is formed.
Is formed due to the insertion of.

On the other hand, the support base lower part 53 has a substantially rectangular shape and is formed so as to reach the lower surface of the through hole 21 provided in the flexible substrate 10 in addition to the surface facing the support base upper part 51. .

In the portion of the through hole 21, a circular through hole 61 for screwing is formed.

A circular hole 63 is also formed at a position of the lower portion 53 of the support base opposite to the hole 55.

Next, a method of manufacturing the electronic component fixing structure on the flexible substrate using the present invention will be described. Here, FIG. 1 is a schematic cross-sectional view showing the manufacturing method, and FIG. 1A corresponds to the cross section of FIG. 2C, and FIG.
It corresponds to the cross section of (b).

That is, first, the flexible substrate 10
The electronic component 30 and upper and lower molds 71 and 73 shown in FIG.
Prepare

Here, the upper die 71 is provided with the support base lower part 53.
Are formed, and a cavity 75 is formed,
The lower mold 73 is provided with a cavity 77 having a shape for forming the support table upper part 51.

Then, a hot melt type conductive adhesive is applied on the conductive patterns 11, 12, 13, and 14 of the flexible substrate 10 shown in FIG. 4 in advance. In this embodiment, as the conductive adhesive, a conductive resin mixed with a polyester resin and having a property of starting to soften at about 120 ° C. was used.

First, as shown in FIG. 1A, the electronic component 30 is inserted into the cavity 77 of the lower mold 73. At this time, the surface 3 of the functional unit main body 31 of the electronic component 30
3 (see FIG. 5) comes into contact with a contact surface 79 provided in the cavity 77.

Two cylindrical movable pins 8 are provided at positions facing the respective metal terminal plates 39 in the cavity 77.
1 is provided, and each movable pin 81 is connected to each metal terminal plate 3.
9 abuts.

Each of the movable pins 81 is configured to be repelled by a predetermined resilient force in the projecting direction (upward) of the movable pin 81, and the upper portion shown in FIG. When the mold 71 is not provided, it protrudes slightly upward from the illustrated position. That is, in the above-described embodiment, in the free state, the movable pin 81 is more than the position shown in FIG.
The movable pin 81 is configured to protrude by about 1 mm, and to apply a resilient pressure of about 100 grams per pin when the movable pin 81 is pushed in by 0.1 mm.

Next, the metal terminal plate 39 in the cavity 77
Two sets of guide pins 83, 83 for positioning the left and right two metal terminal plates 39 are provided at the root part of the.

FIG. 6 is a cross-sectional view of the guide pin 83, and shows a cross section corresponding to the cross section of FIG. As shown in the drawing, between the guide pins 83, there are provided recesses 85 for inserting two metal terminal plates 39, and by inserting the metal terminal plates 39 into the recesses 85, the inside of the cavity 77 of the electronic component 30 is formed. Is performed.

Returning to FIG. 1, the flexible substrate 10 is placed on the lower mold 73 into which the electronic component 30 has been inserted. Thereby, the four conductive patterns 11, 12, 13, 14 of the flexible substrate 10 and the four metal terminal plates 39 are joined via the conductive adhesive.

Next, the upper mold 71 is placed on the flexible substrate 10 and the upper and lower molds 71 and 73 are sandwiched.

Since the cylindrical fixed pins 87 are respectively provided on the upper mold 71 at positions opposed to the movable pins 81, the flexible substrate 10 and the metal terminal plate 39 are fixed by the movable pins 81 and the fixed pins 87. The movable pin 81 is pressed and held by the elastic force generated at that time.

In this state, a high-temperature and high-pressure molten molding resin (such as PBT or POM) is injected from a pin gate 89 provided at a position of the upper mold 71 facing the through hole 19 provided in the flexible substrate 10. Then, the molten mold resin is directly applied to the back surface of the functional unit main body 31 through the through hole 19 of the flexible substrate 10.

As a result, the surface 33 of the functional portion main body 31 is strongly pressed against the contact surface 79 of the cavity 77, and in this state, the entire cavity 75, 77 is filled with the molten mold resin.

Therefore, there is no possibility that a gap is formed between the surface 33 of the functional portion main body 31 and the contact surface 79 of the cavity 77 during the filling of the mold resin.
There is no possibility that the molding resin will enter the surface 33 of the functional section main body 31 because the molding resin does not enter between the layers 9.

The conductive patterns 11, 12, 13, and 14 of the flexible substrate 10 and the metal terminal plate 39 are sandwiched between the movable pins 81 and the fixed pins 87 with an appropriate elastic force. There is no danger of the resin getting in and the connection is secure.

If the fixed pins are attached to both the upper and lower dies 71 and 73 without using the movable pin 81, the thickness of the substrate 18 varies, the thickness of the metal terminal plate 39 varies, and the metal terminal plate 39 varies. The flexible substrate 1 is formed by the upper and lower dies 71 and 73 due to the variation of the bending angle of the 39.
0, the conductive patterns 11, 12, 13, 1
4 and the metal terminal plate 39 may be too strongly clamped. If it is clamped too strongly, the conductive patterns 11, 12, 13, 14 may be destroyed, causing a conduction failure. On the other hand, if the movable pins 81 are used, the conductive patterns 11, 12, 1
Since the joints of the metal terminals 3 and 14 and the metal terminal plate 39 are always clamped with a constant and appropriate clamping force, the conductive patterns 11, 12, 1
There is no fear of destruction of 3,14.

Usually, the temperature of the upper and lower molds 71 and 73 is about 80 ° C., but the temperature of the molten resin to be injected is about 230 to 260 ° C., and this temperature is the same as that of the conductive patterns 11, 12, 13, and 13. 14 is a temperature sufficient to soften the conductive adhesive applied on 14. Therefore, the conductive adhesive is melted by the heat of the molten mold resin. At the same time, the joint between the conductive patterns 11, 12, 13, 14 and the metal terminal plate 39 is pressed from above and below by the injection pressure of the molten mold resin.

Thereafter, the molten mold resin and the conductive adhesive are cooled and solidified to obtain the conductive pattern 1.
The joints between the metal terminals 1, 12, 13, 14 and the metal terminal plate 39 are firmly fixed electrically and mechanically.

Thereafter, when the upper and lower molds 71 and 73 are removed, the electronic component fixing structure to the flexible substrate shown in FIG. 2 is completed.

The through hole 61 provided in the lower part 53 of the support base 50 of the support base 50 shown in FIG. 2 is provided for screwing the support base 50 to another fixing member. The surface 33 of the electronic component 30 can be installed in a state where it is accurately separated from the object to be detected such as another optical disk by a predetermined distance.

The embodiment of the present invention has been described above.
The present invention is not limited to this, and for example, the following modifications are possible. In the above embodiment, the method of fixing the metal terminal plate protruding from the electronic component and the substrate is shown, but it goes without saying that the present invention may be used to fix a single metal terminal plate to the substrate.

In the above embodiment, the flexible substrate is used as the substrate, but a hard substrate or a ceramic substrate may be used instead.

Although the photosensor is used as the electronic component in the above embodiment, other electronic components may be used instead.

In the above embodiment, the pins are provided on both the upper and lower molds, but the pins may be provided only on one of the cavities of the upper and lower molds. At this time, the metal terminal plate or the like is clamped between the pins and the surface of the other mold.

[0052]

As described in detail above, the present invention has the following excellent effects. Since the electrical connection between the conductive pattern of the metal terminal plate and the substrate by the conductive adhesive and the mechanical fixing by the molding resin covering the periphery thereof can be performed in one step, the manufacture thereof can be performed easily and quickly.

When injection molding the molten mold resin into the cavities provided in the upper and lower molds, the joint between the conductive pattern and the metal terminal plate is sandwiched by pins provided in at least one of the cavities of the upper and lower molds. So
Mold resin does not enter between the metal terminal plate and the conductive pattern, and the connection can be reliably and easily made.

Since it can be composed of only the three components of the electronic component, the board, and the support, the number of components is small and the cost can be reduced.

The molten mold resin is directly applied to the back surface of the functional unit main body of the electronic component through the through hole of the substrate, and the surface of the functional unit main body is strongly pressed against the abutting surface of the cavity of the mold while the mold is being pressed. Filling the tee with molten resin,
There is no possibility that the mold resin enters the surface of the electronic component and forms burrs.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view illustrating a manufacturing method according to the present invention.

FIGS. 2A and 2B are views showing a structure for fixing an electronic component to a flexible substrate manufactured by using the method according to the present invention, wherein FIG. 2A is a plan view and FIG. FIG. 3C is a sectional view taken along line BB of FIG. 3A, and FIG. 3D is a rear view.

FIG. 3 is a sectional view taken along line CC of FIG. 2 (a).

FIG. 4 is a plan view showing a flexible substrate 10;

5A and 5B are diagrams showing the electronic component 30, wherein FIG. 5A is a plan view and FIG. 5B is a side view.

FIG. 6 is a cross-sectional view of a guide pin 83 of a lower mold 73;

[Explanation of symbols]

 REFERENCE SIGNS LIST 10 flexible substrate 11, 12, 13, 14 conductive pattern 19 through hole 30 electronic component 31 functional part main body 33 surface 39 metal terminal plate 50 support base 71, 73 upper and lower mold 75, 77 cavity 79 contact surface 81 movable pin 87 Fixed pin 89 Pin gate

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuyuki Yagi 335 Kayajuku, Nakahara-ku, Kawasaki-shi, Kanagawa Imperial Telecommunications Industry Co., Ltd.

Claims (4)

[Claims] 1. A metal substrate having a conductive pattern formed thereon, a metal terminal plate connected to the conductive pattern, and upper and lower metal members provided with cavities to cover upper and lower portions of a portion connecting the conductive pattern and the metal terminal plate. A mold is prepared, and the conductive pattern of the substrate and the metal terminal plate are joined together with a hot-melt type conductive adhesive interposed therebetween. In this state, the substrate is sandwiched by the upper and lower molds. The joint between the conductive pattern and the metal terminal plate is sandwiched by pins provided in at least one of the cavities of the upper and lower molds, and then a molten mold resin is injection-molded into the cavities of the upper and lower molds. At the same time, the conductive adhesive is melted by the heat of the molten molding resin, and at the same time, the joint between the conductive pattern and the metal terminal plate is pressed against by the pressure of the molten molding resin, and cooled in this state Electrical, mechanical metal terminal plate fixing method to the substrate, characterized in that to fix the joining portion of the conductive pattern and the metal terminal plate to solidify the conductive adhesive and the molten molding resin by. 2. The method according to claim 1, wherein said pin is constituted by a movable pin which is resilient with a predetermined resilient force in a projecting direction of the pin. 3. An electronic component having a metal terminal plate protruding from a functional portion main body, a substrate provided with a conductive pattern for joining the metal terminal plate of the electronic component, and an upper and lower mold for holding the substrate from upper and lower surfaces thereof. A through-hole is provided in a portion of the substrate located directly below the functional part main body of the electronic component, and the functional part main body is provided in a mold of the upper and lower molds on which the electronic component is located. A cavity having an abutting surface that abuts the surface of the electronic component, the electronic component and the substrate are sandwiched between upper and lower molds, and the electronic component and the substrate are provided on the substrate of the mold on the side where the electronic component is not located. A molten resin is injected from a pin gate provided at a position facing the through hole, and the molten resin is directly applied to the back surface of the functional unit main body through the through hole of the substrate so that the surface of the functional unit main body contacts the cavity. While pressing strongly against the surface, A method for molding an electronic component and a substrate, characterized in that a molten resin is filled in the substrate. 4. The upper and lower molds are further provided with cavities around a portion where the conductive pattern and the metal terminal plate are joined, and the substrate and the electronic component are sandwiched between the upper and lower molds. And the metal terminal plate of the electronic component are joined via a hot-melt type conductive adhesive, and at least one of the upper and lower mold cavities when sandwiched by the upper and lower molds. The joint provided between the conductive pattern and the metal terminal plate is sandwiched by the pins provided in the mold. In this state, a molten mold resin is injection-molded into the cavity, and the heat of the molten mold resin melts the conductive adhesive. The junction between the conductive pattern and the metal terminal plate is pressed into contact with the molten mold resin by the pressure of the molten mold resin. Electrical junction of the conductive pattern and the metal terminal plate to solidify the Chakuzai, mechanically electronic component and the mold process of a substrate according to claim 3, wherein the fixing.