JP2001162644A - Method for connecting and fixing terminal to substrate by molding resin and connected and fixed structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for connecting a terminal to a substrate by a molding resin so as to be capable of fixing the periphery of the substrate by the molding resin in such a state that the substrate is certainly connected to the terminal and a connected and fixed structure. SOLUTION: A flexible substrate 10 and a terminal 20 are housed in molds 60, 70 in such a state that the terminal 20 is brought into contact with the flexible substrate 10 and a molten molding resin is injected in the cavities 63, 73, which are provided around the part where the flexible substrate 10 and the terminal 20 are brought to a contact state, of the molds 60, 70 to be solidified and, thereafter the molds 60, 70 are detached to fix the terminal 20 to the flexible substrate 10. The molten molding resin is allowed to flow in the cavities 63, 73 so as to go toward the surface on the contact side with the terminal 20 of the flexible substrate 10 while pressing the surface opposite to the contact side with the terminal 20 of the flexible substrate 10 to fill the cavities 63, 73.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and a structure for connecting and fixing terminals to a substrate using a mold resin.

[0002]

2. Description of the Related Art Conventionally, with a metal terminal connected to a conductive pattern provided on a substrate such as a flexible substrate, a molding resin is molded around the metal terminal to connect and fix the conductive pattern and the metal terminal. Is used. As a connection method of this kind, for example, a conductive pattern and a metal terminal are fixed in advance with a conductive adhesive, solder, a reinforcing film, or the like, and then the fixed part is housed in a mold to surround the fixed part. Generally, a method of molding a mold resin is used.

However, according to the above-mentioned conventional method, two steps of a step of fixing the conductive pattern and the metal terminal in advance and a step of molding a molding resin around the step are required, and the manufacturing steps are complicated. Was.

[0004] In order to solve the above-mentioned inconvenience, a contact portion between the metal terminal and the substrate is housed in a mold in a state where the metal terminal is merely brought into contact with the conductive pattern, and the metal terminal is placed around the contact portion. A method is also conceivable in which a mold resin is molded and fixed with the conductive resin and the metal terminal kept in contact with the mold resin. This is preferable because it can be manufactured in one step.

However, in this method, since the metal terminal is merely brought into contact with the substrate, when the molten high-temperature and high-pressure molding resin is press-fitted into the surroundings, the molding resin enters between the substrate and the metal terminal. There is a problem that the electrical connection between the two is hindered. In particular, when a flexible substrate is used as the substrate, the flexible substrate bends with the molten mold resin, so that the mold resin easily enters between the substrate and the metal terminals.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a mold in which the periphery of a substrate can be fixed with a molding resin while the substrate is securely connected to terminals. It is an object of the present invention to provide a method for connecting and fixing a terminal to a substrate with a resin and a connection and fixing structure.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, these substrates and terminals are accommodated in a mold with the terminals connected to the substrates, and the terminals of the mold are connected to the substrates. In the method for connecting and fixing the terminal to the substrate by the mold resin for fixing the terminal to the substrate by injecting the molten mold resin into the cavity provided around the portion and then fixing the terminal to the substrate by removing the mold, The molding resin flows into the cavity such that the molding resin penetrates the surface of the substrate to which the terminals are connected while pressing the back surface to which the terminals of the substrate are connected, and fills the cavity. Further, the substrate is a flexible substrate, and a portion of the flexible substrate to which no terminal is connected is bent in a direction in which the terminal is pressed by the pressing force of the molten mold resin.
Further, the flexible substrate is made of a material which is thermoplastic and is softened by heat and pressure of the molten mold resin. Each terminal is connected to the substrate via a predetermined gap, and a mold resin insertion portion for connecting the upper and lower mold resins of the substrate is provided at any of the portions of the substrate while the terminals are connected. It is characterized by having. Further, the mold resin insertion portion is formed in a portion near a portion where the injected mold resin strongly presses compared to other portions, of a portion between the terminals connected to the substrate. . Also, the present invention provides a method for connecting and fixing terminals to a substrate by molding and molding the resin around the connection portion between the substrate and the terminals in a state where the terminals are connected to the substrate. The structure is characterized in that the substrate is provided with a mold resin insertion portion for connecting the upper and lower mold resins of the substrate at any of the portions where the terminals are connected.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a diagram showing a molded resin case 1 of a built-in substrate type for a rotary variable resistor manufactured by applying the present invention, wherein FIG. 1 (a) is a plan view and FIG. 1 (b) is FIG. ) Is a sectional view taken along the line AA, FIG. 3C is a rear view, and FIG.

As shown in FIG. 1, a molded resin case 1 has three terminals 2 made of a metal plate on a flexible substrate 10.
0 is connected to one end (hereinafter referred to as “contact” in the present embodiment)
In this state, the molded product 30 is formed over the upper and lower surfaces of the flexible substrate 10. Hereinafter, each component and its manufacturing method will be described.

FIG. 2 is a plan view showing the flexible substrate 10. As shown in FIG. 1, a flexible substrate 10 has a circular hole 13 provided in the center of a film 11 made of polyethylene terephthalate (PET), and a current collecting pattern 15 and a resistor pattern 16 are formed concentrically outside the circular hole 13. ,
Further, three conductive patterns (conductive portions) 17 reaching the end of the film 11 are provided at both ends of the resistor pattern 16 and one end of the current collecting pattern 15. Here, the conductive pattern 17 is formed by printing a conductive paste obtained by kneading silver powder (or other various metals such as copper powder and solder powder) with a phenolic thermosetting resin.
The conductive pattern may be made of another material. For example, an elastic conductive paint (for example, a material obtained by kneading a metal powder such as a silver powder with a thermosetting crosslinked urethane resin on the conductive pattern 17) may be used. Other coating layers such as those having a predetermined rubber elasticity even after printing and drying may be printed. Between the conductive patterns 17, two penetrating mold resin insertion portions 19 are provided.

Next, a molded product 30 shown in FIG. 1 is formed so as to cover the flexible substrate 10 from above and below.
On the upper surface, the current collecting pattern 15 and the resistor pattern 16
Is formed, and a through hole 33 penetrating through the circular hole 13 of the flexible substrate 10 is formed at the center thereof.

Next, a method of manufacturing the molded resin case 1 with a built-in substrate will be described. First, the flexible substrate 10 and the terminals 20 are connected to the first and second molds 60 and 70 as shown in FIG.
Sandwiched between. In the drawing, the pattern forming surface of the flexible substrate 10 shown in FIG. At this time, one end 21 of the terminal 20 is connected to the first and second molds 60 and 70 together with the flexible substrate 10.
The other end 23 of the terminal 20 is independently held by the first and second molds. That is, the terminal 20 is securely fixed at the top and bottom by the first and second molds 60 and 70. Further, a pin gate 71 is provided on the second mold 70. In this embodiment, as shown in FIG. 3, the pin gate 71 is opposite to the surface of the flexible substrate 10 on which the terminal 20 is in contact (see FIG. 3). (Rear surface) at the center in the width direction.

Then, a high-temperature and high-pressure molten mold resin of about 260 ° C., for example, polybutylene terephthalate (PBT), PET, PPS or the like is press-fitted from the pin gate 71,
The inside of the cavity 73 provided on the second mold 70 side is filled with the mold resin, and the inside of the cavity 63 provided on the first mold 60 side is also filled with the mold resin.

The molten mold resin injected from the pin gate 71 first comes into contact with the surface (back surface) of the flexible substrate 10 on the side opposite to the terminal 20, so that the second mold 70 is pressed while pressing this surface. Due to the injection pressure (100 to 600 kgf / cm ² ) of the molten mold resin filled in the cavity 73 and the cavity 63 of the first mold 60 and finally filled in the two cavities 63 and 73, the conductivity is increased. The space between the pattern 17 and the terminal 20 is pressed from above and below.

FIG. 4 is an enlarged sectional view of a main part showing a state of the flexible substrate 10 and the terminals 20 when the molten molding resin is injection-molded into the cavities 73 and 63. As shown in the figure, the molten mold resin injected from the pin gate 71 first presses the surface of the flexible substrate 10 on the opposite side to which the terminals 20 are in contact, as indicated by arrows.
Next, the cavity 73 is filled with the molten mold resin while the pressing is continued, and at the same time, the flexible substrate 10 is turned into the cavity 63 from outside the both ends 101, 101, and is also melted into the cavity 63. Fill with resin. Thus, both cavities 6
When the molding resin is filled in the insides of the flexible substrate 3 and 73, the flexible substrate 10 is always pressed against the terminals 20, so that the molten molding resin does not enter between the flexible substrate 10 and the terminals 20. Further, since the flexible substrate 10 is softened by the heat and pressure of the molten mold resin (the softening point of PET is about 150 ° C.), the portion of the flexible substrate 10 without the terminals 20 is replaced with the mold resin as shown in FIG. It curves slightly in the direction in which it is pressed. Therefore, the flexible substrate 10 has a shape that wraps around the terminals 20, so that the molten mold resin is less likely to enter between the flexible substrate 10 and the terminals 20, and there is no occurrence of resin burrs.

The molding resin is supplied to the cavities 73, 6
After the space 3 is filled, the flexible substrate 10 and each terminal 20 are pressed from the front and back surfaces by the pressure of the molding resin as described above, so that there is no possibility that the molding resin enters between them.

In this embodiment, the flexible substrate 10
Since the molding resin insertion portion 19 is provided in a portion where the respective terminals 20 abut, the molten molding resin is also introduced into the cavity 63 through these holes.
Originally, when the flexible substrate 10 does not have such a mold resin insertion portion 19, the force for pressing the flexible substrate 10 against each terminal 20 is stronger. Since the molding resin is connected only at the outer portions of both ends 101 of the flexible substrate 10, the clamping force between the flexible substrate 10 and each terminal 20 by the molding resin is weakened. Therefore, the upper and lower mold resins are combined at the portion of the mold resin insertion portion 19, thereby increasing the clamping force between the flexible substrate 10 and each terminal 20.

In the above embodiment, the position of the pin gate 71 is located immediately behind the portion of the flexible substrate 10 to which the terminal 20 is connected. However, the position is not necessarily limited to this position. For example, as shown by a dotted line in FIG. It may be provided at another predetermined position on the second mold 70 side. In short, the injected molten mold resin presses the terminal 2 of the flexible substrate 10 while pressing the surface on the opposite side of the flexible substrate 10 with which the terminal 20 abuts.
0 wraps around the surface on the side where it abuts, and both cavities 73,
Any position may be used as long as it can flow through the cavities 73 and 63 so as to fill the inside of the cavity 63.

If the first and second molds 60 and 70 are removed after the molten mold resin has cooled and solidified, the mold resin case 1 shown in FIG. 1 is completed.

As described above, according to the present invention, the conductive pattern 17 and the terminal 20 need not be connected and fixed in advance (of course, they may be connected and fixed. That is, the conductive pattern 17 is connected via a conductive adhesive). And the terminal 20 may be connected in advance. When an insulating adhesive is used, the conductive pattern 17 and the terminal 20 may be brought into contact with each other and then applied so as to cover the adhesive.) Connection and fixation can be performed only by the molding resin molding process, and the manufacturing process is simplified. Moreover, according to the present invention, the flexible substrate 10 and the terminal 2
Connection between 0 can be firmly and reliably performed.

In the above-described embodiment, the flexible substrate 10 made of PET is used as the substrate, but a flexible substrate made of another material may be used. At this time, the material of the flexible substrate 10 is preferably a thermoplastic material which is softened by the heat and pressure of the molten mold resin. In some cases, a rigid substrate or a ceramic substrate may be used instead of the flexible substrate.

FIG. 5 is a view showing another embodiment of the present invention, and shows a portion corresponding to the portion of FIG. This embodiment is different from the above embodiment only in that the number of terminals 20 connected to the flexible substrate 10 is increased to five. That is, this is a case where five conductive patterns 17 (see FIG. 2) formed on the flexible substrate 10 are provided. In the case of this embodiment, the mold resin insertion portions 19 are provided only at two central portions in the width direction of the flexible substrate 10. In other words, the molding resin insertion portion 19 is connected to each terminal 2 of the flexible substrate 10.
The mold resin injected from the pin gate 71 is formed at two locations near the portion where the flexible substrate 10 is pressed most, of the portions where the contact is made with the zero.

The reason why the number of the molded resin insertion portions 19 provided is limited as described above for the following reason. As described above, if there is no mold resin insertion portion 19 on the flexible substrate 10, the flexible substrate 1 is attached to each terminal 20.
Although the force for pressing 0 becomes strong, if there is no mold resin insertion portion 19, the upper and lower mold resins after molding are connected only at the outer portions of both ends 101, 101 of the flexible substrate 10. The pinching force of the terminal 20 becomes weak. Therefore, the upper and lower molding resins are joined at the portion of the molding resin insertion portion 19, whereby the clamping force of each terminal 20 is increased. However, the molding resin is inserted only into the central portion where the clamping force may be weakened. The part 19 is provided.

In this embodiment, the central portion of the flexible substrate 10 is pressed by the molten mold resin first, and this portion is pressed by the strongest force. Therefore, the opposite side of the flexible substrate 10 through the mold resin insertion portion 19 (the cavity 63 side)
Molten resin that has flowed into the flexible substrate 1
0 is pressed from the opposite side.
The force pressing the flexible substrate 10 against the terminals 20 is continued until the mold resin is filled in the cavities 73 and 63. On the other hand, if the flexible substrate 10
Assuming that a molding resin insertion portion is provided in a portion between the terminals 20 (portions D and E in FIG. 5) near both ends of the flexible substrate 10, the molten resin in the vicinity of both ends of the flexible substrate 10 is more likely to have a cavity 73 than in the central portion. The force pressing the flexible substrate 10 from the side is weak. Therefore, if the mold resin insertion portions are provided in the portions D and E and the molten mold resin is poured into the opposite surface side of the flexible substrate 10, the force for pressing the flexible substrate 10 on the cavity 73 side to the terminal 20 is increased. Is opposed to the force pressing the flexible substrate 10 against the terminals 20 from the cavity 63 side, so that the force pressing the flexible substrate 10 against the terminals 20 is weakened, and there is a possibility that the mold resin enters the gap between the two. Therefore, as in this embodiment, the mold resin insertion portion 19 is provided only in the vicinity of the portion where the mold resin injected from the pin gate 71 presses the flexible substrate 10 more strongly than the other portions.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to these embodiments, and various modifications may be made within the scope of the claims, the description, and the technical concept described in the entire drawings. Is possible. The shape, number, and material appearing in the embodiment are not limited to these, and may be any shape, number, or material as long as the effect of the present invention can be obtained.

In the above-described embodiment, an example in which the present invention is applied to the mold resin case 1 has been described. However, the present invention can be applied to other various parts, and it is essential that the substrate and the terminal in the mold are brought into contact with each other. It can be applied to any part that has a structure that fixes the terminal to the substrate by injecting the molten mold resin into the cavity provided around the part that has been solidified and then removing the mold. .

The position where the mold resin insertion portion is provided is as follows:
The present invention is not limited to the above embodiment, and various changes can be made in the number and position.

[0028]

As described in detail above, the present invention has the following excellent effects. Since the molten mold resin was pressed around the back surface to which the terminals of the board were connected and wrapped around the surface to which the terminals of the board were connected, and flowed into the cavity so as to fill the cavity, the substrate Is pressed against the terminals, so that the molding resin does not enter between the substrate and the terminals, and the periphery of the substrate can be firmly fixed with the molding resin while the substrate is securely connected to the terminals. Can be done. This is particularly effective when the substrate is a flexible substrate.

When a flexible substrate made of a material which is thermoplastic and is softened by the heat and pressure of the molten mold resin is used as the substrate, the flexible substrate has a shape which wraps the terminals by the heat and pressure of the molten mold resin. Since it is bent, it becomes more difficult for the molten mold resin to enter between the flexible substrate and the terminal, and the connection and fixing between the two can be performed more reliably.

Since the molding resin insertion portion is provided at any part of the substrate while the terminals are connected, the clamping force between the substrate and the terminals by the molding resin can be increased.

In the case where the molded resin insertion portion is formed in a portion near the portion where the injected molded resin presses the substrate more strongly than the other portions, of the portion between the terminals connected to the substrate, The terminals can be effectively fixed to the substrate. This is particularly effective when the number of terminals is large.

[Brief description of the drawings]

FIG. 1 is a diagram showing a molded resin case 1 with a built-in substrate for a rotary variable resistor manufactured by applying the present invention;
FIG. 1A is a plan view, and FIG. 1B is an A-A view of FIG.
Sectional view, (c) is a back view, (d) is (a)
It is BB sectional drawing of the.

FIG. 2 is a plan view showing a flexible substrate 10;

3 (a) and 3 (b) are views showing a method for manufacturing a molded resin case 1. FIG.

FIG. 4 is an enlarged sectional view of a main part showing a state of a flexible substrate 10 and terminals 20 when a molten mold resin is injection-molded into cavities 73 and 63.

FIG. 5 is a diagram showing another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mold resin case 10 Flexible board (substrate) 11 Film 15 Current collecting pattern 16 Resistor pattern 17 Conductive pattern (conductive part) 19 Mold resin insertion part 20 Terminal 30 Molded product 60 First mold 63 Cavity 70 Second mold 71 pin gate 73 cavity

Continuation of the front page (72) Inventor Nobuyuki Yagi 335 Karuku, Nakahara-ku, Kawasaki-shi, Kanagawa Prefecture F-term in Teikoku Communication Industrial Co., Ltd. 4F202 AA24 AA34 AD03 AD05 AD08 AD35 AH36 CA11 CB01 CB12 CB20 CQ03 4F206 AA24 AA34 AD03 AD05 AD08 AD35 AH36 JA07 JB12 JB20 JQ81 5F061 AA01 BA03 BA05 CA21 DA06

Claims (6)

[Claims] In a state where the terminals are connected to the substrate, the substrate and the terminals are accommodated in a mold, and the molten mold resin is filled in a cavity provided around a portion of the mold where the substrate and the terminals are connected. Injecting and solidifying, and then connecting and fixing the terminal to the substrate by using a mold resin for fixing the terminal to the substrate by removing the mold, the molten mold resin presses the back surface of the substrate to which the terminal is connected. A method of connecting and fixing a terminal to a substrate by using a mold resin, wherein the terminal is made to flow into a cavity so as to fill around the surface of the substrate to which the terminal of the substrate is connected while filling the cavity. 2. The method according to claim 1, wherein the substrate is a flexible substrate, and a portion of the flexible substrate to which no terminal is connected is bent in a direction in which the terminal is pressed by a pressing force of the molten mold resin. Item 1
A method for connecting and fixing a terminal to a substrate using the mold resin described above. 3. The connection and fixing of terminals to the substrate by the molding resin according to claim 2, wherein the flexible substrate is made of a material which is thermoplastic and is softened by the heat and pressure of the molten molding resin. Method. 4. Each of the terminals is connected to the substrate via a predetermined gap, and a mold resin insert for connecting the upper and lower mold resins of the substrate to any of the portions of the substrate while the terminals are connected. 2. A unit is provided.
Or the method of connecting and fixing the terminal to the substrate using the mold resin according to 2 or 3. 5. The mold resin insertion portion is formed in a portion near a portion where the injected mold resin is strongly pressed as compared with other portions, of a portion between the terminals connected to the substrate. 5. The method according to claim 4, wherein the terminal is fixed to the substrate by the mold resin. 6. A connection between a terminal and a substrate by means of a molding resin formed by molding a molding resin around a connection portion between the substrate and the terminal in a state where the terminal is connected to the substrate. In the above structure, the substrate is provided with a mold resin insertion portion for connecting the upper and lower mold resins of the substrate to any of the portions where the terminals are connected. Connection fixed structure to.