JP2000031339A - Lightning-resistant transmitting body and terminal network controller mounted with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent leach of a sealing agent and, at the same time, to prevent bubbles in the gap between optical communication circuit components and a printed board and the deterioration of the adhesion between the components and board by using two kinds of insulating sealing agents having different viscosities. SOLUTION: An optical communication circuit section composed of optical communication circuit components 2 mounted on and soldered to a printed board 1 requiring a dielectric strength and copper foil 4 provided on the substrate 1 is covered by attaching a molded frame 5 made of an electrically insulating material to the board 1 and the gap between the frame 5 and substrate 1 is filled up with a sealing agent 6 having a high viscosity and high electric insulating property. Then a lightning resistant transmitting body is formed by filling up the inside of the frame 5 with another sealing agent 7 having a low viscosity and a low electric insulating property to such a height that the agent 7 can completely cover the component 2 and curing both sealing agents 6 and 7. Therefore, the deterioration of the insulating property of the transmitting body due to bubbles produced in the gaps between optical communication circuit components or between the components and the printed board 1 can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lightning-resistant transmission body used for equipment connected to a telephone line.

[0002]

2. Description of the Related Art Conventionally, lightning-resistant transmission bodies used in equipment connected to telephone lines requiring high lightning resistance, such as terminal network controllers, require lightning resistance as shown in FIGS. After mounting and soldering optical communication circuit components for electrical insulation on the printed circuit board of the device to be formed, and surrounding the optical communication circuit part consisting of the optical communication circuit components and copper foil on the printed circuit board , A molded frame made of an insulating material with a necessary and sufficient height on all sides is fixed to a printed circuit board, and a sealant with electrical insulation is applied and cured in this frame so that the inside of the frame has an insulating structure. Was configured to.

[0003]

However, in such a conventional lightning-resistant transmission body, a high-viscosity sealant is applied so that the sealant does not protrude from a gap between the molding frame and the printed circuit board.

For this reason, the high-viscosity sealant does not penetrate into the gap between the optical communication circuit components and the gap between the optical communication circuit component and the printed circuit board, and air bubbles easily accumulate. Repeated expansion and contraction due to long-term environmental stress such as temperature changes due to air gaps and air bubbles deteriorate the adhesion between the printed circuit board and optical communication circuit components and the sealant, and the insulation between the optical communication input and output Had a problem of decreasing.

Further, in order to completely cover the optical communication circuit component with the sealant, it is necessary to fix a frame made of an insulating material having a necessary and sufficient height to a printed circuit board.

[0006]

In order to solve the above-mentioned problems, the present invention first applies a high-viscosity electrically insulating sealant to a gap between the molding frame and a printed circuit board and closes the gap. A low-viscosity electrically insulating sealing agent is applied and dried so as to cover the entire optical communication circuit portion in the molding frame, so that the interior of the molding frame made of the electrically insulating material has an insulating structure.

According to the above invention, the low-viscosity electrically insulating sealing agent does not flow out of the gap between the molding frame or the mold and the printed circuit board, has high permeability throughout the molding frame, and generates bubbles. It is possible to apply and cure a low-viscosity, low-electricity insulating sealant to form a unit, so that air bubbles accumulate in gaps between the optical communication circuit components and in gaps between the optical communication circuit components and the printed circuit board, resulting in deterioration of insulation. The problem can be solved.

Further, it is possible to reduce the cost by reusing the molding frame and using the mold.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The lightning-resistant transmission body of the present invention includes the above-described four-sided optical communication circuit component formed by a combination of a light receiving element and a light emitting element formed on the printed circuit board requiring dielectric strength. A molded frame made of an electrically insulating material having a necessary and sufficient height is fixed to the printed circuit board, and a high-viscosity electrically insulating sealing agent is filled in a gap between the molded frame and the printed circuit board. It is applied, and then a low-viscosity electrically insulating sealing agent is applied and dried so as to cover the entire optical communication circuit component in the molding frame to form a unit.

This prevents the sealant from protruding from the gap between the molding frame and the printed circuit board, improves the permeability of the sealant into the gap between the optical communication circuit components, and causes factors such as generation of bubbles and deterioration of dielectric strength. Can be eliminated.

[0011] Further, a molding frame made of the above-mentioned electrically insulating material is made of a material having a releasability from the above-mentioned two kinds of sealing agents,
It is easy to remove and reuse after curing the sealant, and it is possible to configure a lightning-resistant transmission body in the removed state,
The molding frame can be made of a wide range of materials that do not require electrical insulation. Further, the cost can be reduced by reusing the molding frame.

Further, instead of the molding frame made of the above-mentioned insulating material and the above-mentioned molding frame which does not require reusable electric insulation, the enclosure is constituted by a separated mold which is subjected to a release treatment of resin or metal. After applying and curing the sealant, the mold is removed to form the lightning-resistant transmission body.

Accordingly, as described above, a molding frame is not required, which is not only economically advantageous, but also enables mechanization and automation, and can stabilize quality together with cost reduction.

In addition, instead of the molding frame and the mold, the high-viscosity electrically insulating sealing agent is further made highly viscous and non-flowable, and is applied in an enclosing shape so as to have the same height as the molding frame and the mold. Next, the low-viscosity electrically insulating sealing agent is applied and cured inside the enclosure made of the sealing agent to form a lightning-resistant transmission body.

For this reason, it is possible to construct a lightning-resistant transmission body which eliminates the cause of deterioration in dielectric strength with only two types of sealants having different viscosities without the need for the molding frame or the mold, and is economical in terms of cost and equipment. This is advantageous.

Further, any one of the lightning-resistant type transmission bodies is mounted on a communication circuit section of the terminal network control device which is connected to the meter reading meter by a transmission line and controls communication, thereby increasing an insulation distance of the communication circuit section. By doing so, it is possible to realize a terminal network control device that has significantly improved lightning resistance with a small change and cost.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a lightning-resistant transmission body and a terminal network control device equipped with the same according to the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 shows an optical communication circuit component composed of a combination of a light receiving element and a light emitting element mounted on a printed circuit board of a lightning-resistant transmission body according to Embodiment 1 of the present invention, Surround the optical communication circuit section made of copper foil on the printed circuit board with the required insulation distance,
FIG. 2 is an external view of the frame formed of an insulating material whose four sides are sufficiently higher than the components of the optical communication circuit section as viewed from above before fixing the frame. FIG. 3 is a cross-sectional view of a portion in which a sealing agent such as silicon or urethane having high viscosity is applied to the gap portion to close the gap, as viewed from the side. FIG. FIG. 5 is a cross-sectional view as seen from a side surface where a low electrical insulating sealant 7 is applied and cured so as to have a height completely covering the optical communication circuit component 2.

In FIG. 1, reference numeral 1 denotes an optical communication circuit component 2 mounted and soldered together with other electronic components 3, and a printed circuit board 5 composed of a copper foil 4, and 5 mounted on the printed circuit board 1. Copper foil 4 connected to said optical communication circuit component 2
This is a molded frame made of an electrically insulating material which is inserted into and fixed to the printed circuit board 1 so as to surround the optical communication circuit portion made of. 6 is a high-viscosity, electrically insulating silicon or urethane applied to the corners of the molding frame 5 that comes into contact with the printing substrate 1 so as to fill gaps between the molding frame 5 inserted and fixed to the printed circuit board 1. And 7 is a low-viscosity electrically insulating silicon applied and dried inside the molding frame 5 so as to completely cover the optical communication circuit component 2 and the copper foil 4 connected thereto thereafter. And a sealant such as urethane.

Next, the operation will be described. As described above, mounting on the printed circuit board 1 that requires electrical
An optical communication circuit part composed of an optical communication circuit component 2 formed by soldering and a copper foil 4 on the printed circuit board 1 is covered by mounting a molded frame 5 made of the electrically insulating material on the printed circuit board 1, Next, the high-viscosity electrically insulating sealing agent 6 is applied to the gap between the molding frame 5 and the printed circuit board 1 to fill the gap.

Next, the low-viscosity electrically-insulating sealing agent 7 is applied to the inside of the molding frame 5 to a level that completely covers the optical communication circuit component 2, and is applied together with the high-viscosity electrically-insulating sealing agent 6. It is cured to form a lightning-resistant transmission body.

(Embodiment 2) FIG. 4 shows a lightning-resistant transmission body according to Embodiment 2, and the printed circuit board 11 is similar to Embodiment 1.
The lightning-resistant transmission body configured above, wherein the viscosity is different.
FIG. 7 is a cross-sectional view of the molding frame after the sealing agents 16 and 17 such as silicon and urethane have been cured and the molding frame is removed.

In the figure, reference numeral 15 denotes the mold releasability of the molding frame 5 made of the above-mentioned electrically insulating material from the two types of sealing agents 16 and 17 of silicon or urethane having different viscosities which do not require electrical insulation. It is a molding frame made of a material such as Duracon.

Next, the operation will be described. As described above, the frame 15 formed by molding a Duracon or the like having a releasability from the two kinds of sealing agents 16 and 17 having different viscosities which does not require the electric insulation is formed by the mold in the same manner as in the first embodiment. A high-viscosity electrically insulating sealing agent 16 is applied to the gap between the molding frame 15 and the printed circuit board 11 as in the first embodiment to fill the gap. Similarly, a low-viscosity electrically insulating sealing agent 17 is applied to a level covering the optical communication circuit component 2 and is cured together with the high-viscosity electrically insulating sealing agent 16.

Next, a molding frame 15 having a releasability from the two kinds of sealing agents 16 and 17 having different viscosities which does not require the electric insulating property is used to make use of its characteristics to make the printed circuit board 11 and the viscosities different in viscosity. It is removed from the two types of sealants 16 and 17 to form a lightning-resistant transmission body, and the molded frame 15 is reused.

(Embodiment 3) FIG. 5 shows a lightning-resistant transmission body of Embodiment 3 of the present invention, in which the molded frame 15 made of a reusable Duracon or the like which does not require electrical insulation is used. A cross-sectional view as viewed from the side before applying two types of sealants 26 and 27 such as silicon and urethane having different viscosities when using a separated mold made of a metal or resin subjected to mold release processing instead. FIG. 6 is a graph showing the results obtained in Example 3 having different viscosities.
It is sectional drawing seen from the side surface after the type | mold was removed after apply | coating and hardening the kind of sealing agents 26 and 27.

In the figure, reference numeral 8 denotes a separate mold made of a reusable metal or resin which does not require electrical insulation. The sealant 26 is made of two kinds of silicone and urethane having different viscosities. The mold is subjected to a release treatment so as to be detachable from the device 27.

Next, the operation will be described. As described above, the separation mold 8 made of metal or resin and subjected to the release treatment is mounted on the printed circuit board 21 in the same manner as in the first and second embodiments. 1
2 and 3, a high-viscosity electrically insulating sealing agent 26 is applied to fill the gaps, and then the molds 8 are filled in the first and second embodiments.
Similarly, a low-viscosity electrically insulating sealing agent 27 is applied to a level covering the optical communication circuit component 2 and is cured together with the high-viscosity electrically insulating sealing agent 26.

Next, the separation mold 8 made of the above-mentioned metal or resin and subjected to a release treatment is removed to form a lightning-resistant transmission body.

(Embodiment 4) FIG. 7 shows a lightning-resistant transmission body of Embodiment 4, in which the molding frames 5, 15 and the mold 8 of Embodiments 1 to 3 are replaced with those of Embodiments 1 to 3. Sealing agents 6 and 16, such as silicon and urethane, which are highly viscous and electrically insulating.
26 are made more viscous and non-fluid, and the molding frames 5, 15
FIG. 8 is an external view seen from the top side, which is applied so as to be similar to the wall of the mold 8, and FIG. FIG. 3 is a cross-sectional view as seen from the side where an electrically insulating sealing agent 37 having a low viscosity is applied and cured as in the case of FIG.

Referring to FIG. 9, reference numeral 9 denotes a high viscosity non-flowable sealant 6, 16 or 26 made of high-viscosity electrically insulating silicon or urethane of the first to third embodiments.

Next, the operation will be described. As described above, the high-viscosity, non-flowable sealant 9 is applied so that the position and the height are the same as those of the molding frames 5 and 15 and the mold 8 of the first to third embodiments.

Next, as in the first to third embodiments, an electrically insulating sealing agent 37 having a low viscosity is applied to the optical communication circuit component 2 in the same manner as described above.
Is applied to a height that covers it, and is cured together with the high-viscosity, non-fluid, electrically insulating sealant 9 to form a lightning-resistant transmission body.

(Embodiment 5) FIG. 9 is an external view of a terminal network control device equipped with a lightning-resistant transmission body of Embodiment 1 as viewed from above.

In the figure, reference numeral 40 denotes a lightning-resistant transmission body according to the first embodiment, and reference numeral 41 denotes a printed circuit board of a terminal network control device on which it is mounted. 43 is a terminal block connected to the printed circuit board 41 of the terminal network control device by mounting and soldering, and connecting to an external device such as a center automatic meter reading device via a transmission line via a meter reading meter or a telephone line; Reference numeral 44 denotes a case that accommodates and fixes the printed circuit board 41 of the terminal network control device and constitutes the terminal network control device. Reference numeral 45 denotes a case that is attached to the case 44 and connected to an external device via a connection line to the terminal block 43. It is a case lid for covering the terminal block 43 part.

Next, the operation will be described. As described above, the terminal block 43 and the optical communication circuit component 42 are mounted and soldered on the printed circuit board 41 of the terminal network control device simultaneously with other components.

Next, the optical communication circuit section composed of the optical communication circuit components 42 on the printed circuit board 41 is surrounded by an electrically insulating molding frame 46 as in the first embodiment, and two types of insulating seals having different viscosities are used. The lightning-resistant transmission body 40 is formed by applying and curing the agent. Next, the lightning-resistant transmission body 40
The printed circuit board 41 of the terminal network control device equipped with is stored and fixed in the case 44.

After connecting the terminal block 43 to an external device by a connection wire, the case cover 45 is attached and fixed to the case 44.

[0039]

As described above, according to the lightning-resistant transmission body of the present invention, the molded frame 5 made of the above-mentioned electrically insulating material, the molded frame 8 made of a material other than the above-mentioned material, and the molded frame 8 having the releasability. The gap between the separated mold 9 made of metal or resin and the printed board 1 is filled with a highly viscous electrically insulating sealant 6 and then the internal optical communication circuit component 2 is completely filled. By applying two kinds of sealants, that is, applying a low-viscosity electrically-insulating sealant 7 to a height to cover the same and curing together with the high-viscosity electrically-insulating sealant 6, the conventional molding frame 5 is used. In order not to protrude from the gap between the printed circuit board 8 and the mold 9 and the printed circuit board 1, the viscosity of the sealant cannot be reduced, so that air bubbles are generated between the optical communication circuit component 2 and the printed circuit board 1, Is poor and space is created due to environmental changes, etc. It is possible to measure the problem that the chill.

Further, as described above, the molding frame 5 is formed into a molding frame 8 made of a material having releasability from the sealing agents 6 and 7, so that the sealing agents 6 and 7 are removed after being cured and reused. Can be economical.

Further, a separate mold 9 made of a metal or resin subjected to a mold release treatment is used in place of the molding frames 5 and 8, and is removed after the sealing agents 6 and 7 are cured, thereby enabling mechanization and automation. Therefore, the quality can be improved and the molding frames 5 and 8 are not required, which is economically advantageous.

Further, instead of the molding frames 5 and 8 and the mold 9, a high-viscosity electrically insulating sealing agent 6 for filling the gap is made to have a higher viscosity and non-flowability, and It is applied so as to have the same height and position as the molding frames 5 and 8, and the low-viscosity electrically insulating sealing agent 7 is applied and cured so as to completely cover the optical communication circuit component 2. By configuring the body, the equipment and man-hours can be reduced without the need for the molding frames 5 and 8 and the mold 9.

Further, the lightning-resistant type transmission body 11 constructed by any of the above-described embodiments 1 to 4 is employed in the optical communication circuit unit mounted on the printed circuit board 12 of the terminal network control device as described above. Accordingly, a terminal network control device having high lightning resistance can be realized at a low cost without requiring a relatively large-scale change.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a lightning-resistant transmission body according to a first embodiment of the present invention before a molded frame made of an insulating material is fixed on a printed circuit board.

FIG. 2 is a cross-sectional view of the transmission body when a high-viscosity electrically insulating sealing agent is applied.

FIG. 3 is a cross-sectional view of the transmission body when a low-viscosity electrically insulating sealing agent is applied.

FIG. 4 is a cross-sectional view of a lightning-resistant transmission body according to a second embodiment of the present invention when a molding frame is removed after a sealant is cured.

FIG. 5 is a sectional view of a lightning-resistant transmission body according to a third embodiment of the present invention, in which a mold is used instead of a molding frame.

FIG. 6 is a cross-sectional view after removing the mold of the transmission body.

FIG. 7 is a cross-sectional view of a lightning-resistant transmission body according to a fourth embodiment of the present invention, in which a high-viscosity sealant is applied so as to surround it.

FIG. 8 is a cross-sectional view showing a state where a low-viscosity sealant is applied and cured in the transmission body.

FIG. 9 is an external perspective view of a terminal network control device equipped with a lightning-resistant transmission body according to a fifth embodiment of the present invention.

FIG. 10 is a cross-sectional view of a conventional lightning-resistant transmission body before a sealant is applied.

FIG. 11 is a cross-sectional view of the transmission body after applying and curing a sealant.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printed circuit board 2 Optical communication circuit component 3 Other electronic components 4 Copper foil 5 Molding frame of an electrically insulating material 6 Low-viscosity electrically insulating sealing agent 7 High-viscosity electrically insulating sealing agent 8 Separation from a sealing agent Molding frame having moldability 9 Separation mold that has been subjected to release processing 10 High-viscosity, non-flowable sealant 11 Lightning-resistant transmission body 12 Terminal board controller printed circuit board 13 Terminal block 14 Case 15 Case lid

Claims (5)

[Claims] 1. An optical communication circuit section comprising a combination of a light receiving element and a light emitting element formed on a printed circuit board.
A molded frame made of an electrically insulating material with a necessary and sufficient height on all sides is fixed to a printed circuit board, and a high-viscosity electrically insulating sealant is applied to the gap between the molded frame and the printed circuit board. A lightning-resistant transmission unit that is made into a unit by applying and curing a low-viscosity electrically insulating sealant on the entire inside so that the optical communication circuit unit is covered. 2. An optical communication circuit section formed by a combination of a light receiving element and a light emitting element formed on a printed circuit board.
A molding frame made of a releasable material that does not have electrical insulation with sufficient height on all sides is fixed to the printed circuit board, and a high-viscosity electrically insulating sealant is inserted into the gap between this molding frame and the printed circuit board. Apply, then apply a low-viscosity electrically insulating sealant over the entire molding frame so that the optical communication circuit section is covered,
A lightning-resistant transmission body configured to remove and reuse the molded frame after the two types of sealants have hardened. 3. An optical communication circuit formed by a combination of a light receiving element and a light emitting element formed on a printed circuit board.
A mold of a separation mold having a mold release treatment with a necessary and sufficient height on all sides is fixed to a printed circuit board, and a high-viscosity electrically insulating sealant is applied to a gap between the mold and the printed circuit board. A lightning-resistant transmission body configured to apply an electrically insulating sealing material having a low viscosity so as to cover the optical communication circuit portion as a whole, and to separate and remove the mold after the two types of sealing materials cure. 4. An optical communication circuit portion formed by a combination of a light receiving element and a light emitting element formed on a printed circuit board.
Applying the high-viscosity, non-flowable sealant of the above-mentioned high-viscosity, non-flowable sealant so that all sides have a necessary and sufficient height. A lightning-resistant transmission body in which a low-viscosity electrically insulating sealant is applied to the entire interior of the enclosure made of a conductive sealant so as to cover the optical communication circuit portion, and the two types of sealants are cured to form a unit. 5. A terminal network control comprising the lightning-resistant transmission body according to claim 1, connected to a meter reading meter via a transmission line, and connected to a center automatic meter reading device via a telephone line. apparatus.