JP2787387B2 - Optical coupling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical coupling device (photocoupler).

[0002]

2. Description of the Related Art FIG. 6 shows the structure of a conventional double transfer mold type optical coupling device (photocoupler). In a conventional optical coupling device, a light emitting element 1 (LED) and a light receiving element 2 (phototransistor) are connected by a 42 alloy or C
After fixing to the lead frames 3 and 4 made of u or the like with an Ag paste (not shown) or the like, and electrically connecting the light emitting and receiving elements 1 and 2 to the lead frames 3 and 4 using gold wires 5 or the like. The mainstream is a type that is covered with a light-transmitting resin 6 such as silicon and then molded with a light-shielding resin 7 mainly made of an epoxy resin or the like (conventional example 1). FIG. 7 is a process flowchart showing the manufacturing process of the optical coupling device shown in FIG.

[0003]

Generally, an optical coupling device is
It is like a relay used for a power supply unit and the like, and requires a withstand voltage between a primary (light emitting side) and a secondary (light receiving side). Therefore, it is preferable that the distance between the light emitting side and the light receiving side is as long as possible.

However, in the case of the prior art 1, since the positioning accuracy of the two lead frames 3 and 4 is limited, the distance between the light emitting element 1 and the light receiving element 2 is reduced to some extent to ensure optical coupling. Required, thus limiting the insulation resistance.

[0005] In order to solve such a problem, there has been an optical coupling device in which a light emitting / receiving single element is inserted into a preformed case and sealed. The structure is shown in FIGS. 8 and 9, and the process flow chart is shown in FIG. That is, the light emitting side single device 1a and the light receiving side single device 2a are inserted into the outer case 8 molded using polycarbonate or the like so that the light receiving and emitting surfaces face each other and have substantially the same optical axis. The molded inner case 9 is inserted and fixed with a fixing light-shielding resin 7 such as an epoxy resin (conventional example 2).

In this structure, since the distance between the light receiving and emitting elements 1 and 2 can be made longer than that of the double transfer mold type, a high insulating property can be obtained. However, as shown in the process flowchart of FIG. However, there are many processes that require single-piece processing and manual work, so that the number of production steps is increased, and as a result, the production cost per product is high.

In view of the above problems, an object of the present invention is to provide an optical coupling device capable of improving electrical insulation between light receiving and emitting and simplifying a manufacturing process.

[0008]

The present invention according to claim 1 according SUMMARY SUMMARY In order to achieve the above, as shown in FIG. 1, the translucent resin 16 Nitemo
The light emitting side single device 13
A light emitting side light shield 18 Yotsute formed by integrally molding, translucent
Light receiving side unit device 15 molded with conductive resin 16
The a light receiving side light-shielding member 19 formed by molding in Yotsute integrally with the thermoplastic resin, the respective light shielding member 18 and 19, the light emitting
There is provided an optical path chamber 21 for forming an optical path from the side single device 13 to the light receiving side single device 15 .
19, the substantially arranged to optically combined on the same optical axis, integrally further by the two light shielding members 18 and 19 and the same thermoplastic exterior resin 20 in both single device 13, 15 the light path chamber 21 It is molded.

According to a second aspect of the present invention, a thermoplastic resin material according to the first aspect is characterized in that the material of the thermoplastic resin is a polyphenylene
Rufide (PPS), Polycarbonate (PC), PO
Polybutylene terephthalate (PBT), crystalline polymer
-, Amorphous polymers or thermoplastics such as liquid crystal polymers
One or a mixture of these resins
is there.

[0010] according to item (1) above third aspect, claim 1 Insulation resistance of thermoplastic resins described, + 25 ° C in at ambient temperature of about ^{10 12} Omega or more and + 100 ° C before and after the high temperature ^{10 11} It is set to Ω or more.

[0011]

The light emitting side single device 13 and the light receiving side single device 15 are provided.
Are individually subjected to an injection molding to form two light shielding members 18 and 19. These two light shields 18, 1
The periphery of 9 is integrally molded with an exterior resin 20 so that the two single devices 13 and 15 are optically coupled. Then, since the light path chamber 21 can be formed in each of the light shielding members 18 and 19, the optical path length can be increased, and the insulation resistance of both the light shielding members 18 and 19 and the exterior resin 20 is set large. Can ensure sufficient insulation. In addition, both
The light shielding bodies 18, 19 and the exterior resin 20 are made of the same resin material.
By forming, when the exterior resin 20 is injected,
A part of the surface of 18, 19 is melted to
The two light shielding members 18 and 19 and the outside as a secondary molded body
The resin interface with the mounting resin 20 can be eliminated.

According to a second aspect of the present invention, a thermoplastic resin material is used.
Is polyphenylene sulfide (PPS), polycarbonate
Bonate (PC), polybutylene terephthalate (PB
T), crystalline polymer, amorphous polymer, or liquid crystal
One or more of thermoplastic resins such as polymers
These are mixtures, which have high workability and molding accuracy,
Since molding is excellent, molding can be performed efficiently. In addition,
In claim 3, the insulation resistance of the thermoplastic resin is set at + 25 ° C.
At room temperature after 10 ¹² Ω or more and around + 100 ° C
By setting to 10 ¹¹ Ω or more at high temperature,
To meet specified standards by increasing the dielectric strength of
You.

[0013]

FIG. 1 is a sectional view of an optical coupling device showing an embodiment of the present invention, FIG. 2 is a process flow chart showing a method of manufacturing the optical coupling device, and FIG. ,
FIG. 4 is a view showing a state where each light shield is formed, and FIG. 5 is a view showing a state where both light shields are positioned.

[0014] As shown, the optical coupling device of the present embodiment (Fuotokapura) is molded with the optical coupling device main assembly 11, the light emitting side alone devices 13 that are molded together with the light emitting side lead frame 12, together with the light receiving side lead frame 14 Is
The light-receiving-side single device 15 is disposed so as to be optically coupled substantially on the same optical axis.

[0015] - emitting element (not shown) and a light receiving element (Fig.
(Not shown) are mounted on each of the lead frames 12 and 14 .
Are, are integrally molded by translucent resin 16, its
The light emitting side and light receiving side unit devices 13 and 15 are respectively provided.

The optical coupling device main body 11 includes the light emitting side unit.
Each of the body device 13 and the light-receiving-side single device 15 is composed of a light-emitting-side light-shielding member 18 and a light-receiving-side light-shielding member 19 which are individually formed, and an exterior resin 20 integrally molded around these members.

The light shielding members 18 and 19 are made of, for example, heat such as polyphenylene sulfide (PPS), polycarbonate (PC), polybutylene terephthalate (PBT), a crystalline polymer, an amorphous polymer, or a liquid crystal polymer. It is formed by injection molding using one of the plastic resins or a mixture thereof. Here to use a thermoplastic resin, the resin molding temperature has a lower characteristic, because impact on the single device 13, 15 is considered to be low. Further, the insulation resistance of the thermoplastic resin at room temperature around + 25 ° C. is 10%.
10 ¹¹ at high temperature above ¹² Ω and around + 100 ° C
A material having a characteristic of Ω or more is used, so that electrical insulation between the light receiving and emitting lead frames 12 and 14 is ensured. Then, the specified standard (Federal Republic of Germany:
It conforms to VDE standard No. 0884) and can respond to requests for product standardization and mass production.

The light shielding members 18 and 19 emit light.
In order to form an optical path from the side unit device 13 to the light receiving side unit device 15, a round hole-shaped optical path chamber 21 is formed. The light path chamber 21 is sealed when the two light shielding members 18 and 19 are arranged to face each other, and has a length equal to the length of the light emitting side device.
The chair 13 and the light-receiving-side single device 15 are long so as to be electrically insulated from each other.

The exterior resin 20 comprises the light shielding members 18 and 1
The same light-shielding material as that of No. 9 is used, and the entire periphery thereof is molded by injection molding.

In FIG. 1, reference numeral 16a denotes a light transmitting lens for improving the light directivity.

The optical coupling device having the above structure is manufactured as shown in the flowchart of FIG. First, as shown in FIG. 3, a light emitting element (not shown) and a light receiving element (not shown) are connected to a light emitting side.
And mounted on the light-receiving-side lead frames 12 and 14, molded with a translucent resin 16, and arranged to face each other as the light-emitting and light-receiving-side single devices 13 and 15 .

Next, as shown in FIG. 4, the light emitting side alone devices 1
For each of the light-receiving side device 3 and the light-receiving-side single device 15, the light-shielding members 18 and 19 are individually formed by injection molding with a thermoplastic resin. At this time, the optical path chamber 21 is formed long.

[0023] Then, as shown in FIG. 5, both stand-alone device 1
The two light shields 18 and 19 are opposed to each other so that the light shields 3 and 15 are optically coupled on substantially the same optical axis in the optical path chamber 21. While pressing these members from behind, as shown in FIG. And mold integrally.

The above operation is performed simultaneously using a plurality of lead frames 12 and 14 connected in a cascade in a state where a plurality of devices are juxtaposed. Thereafter, the lead frames 12 and 14 are cut for each optical coupling device main body 11, and individual optical coupling devices are completed, and are subjected to a test process.

Here, since the light path chamber 21 is formed to be long and a resin material having high insulation resistance is used for the light shielding members 18 and 19 and the exterior resin 20, the light emitting side single device 1
3 and the light-receiving-side single device 15 can be separated, and high insulation properties can be obtained.

Further, for example, in the conventional example 2 shown in FIG. 10, the processing for each of the outer case and the inner case is performed individually, whereas the type of the present invention, as shown in FIG. Since the treatment can be performed up to the molding stage as it is, the work of positioning and the like can be easily performed by the mold, and the number of steps can be reduced. Therefore, manual work can be eliminated, and inexpensive products can be provided by automation. Moreover, by molding the exterior resin 20 with a mold, the outer dimensional accuracy can be improved as compared with the fitting type as in Conventional Example 2.

When the light shielding members 18 and 19 are placed in contact with each other, a slight gap may be formed due to a molding error. Intrusion of disturbance light can be prevented. Therefore, a highly reliable optical coupling device can be provided.

In addition, since the light shielding members 18 and 19 and the exterior resin 20 are formed of the same resin material, a part of the surface of the light shielding members 18 and 19 is melted when the exterior resin 20 is injected, so that the primary The resin interface between the mold body and the secondary mold body can be eliminated. Therefore, it is possible to prevent resin destruction or the like due to thermal expansion or thermal contraction.

It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that many modifications and changes can be made to the above-described embodiment within the scope of the present invention.

For example, if the shape of the opening on one side of the light shielding members 18 and 19 is made convex and the shape of the opening on the other side is made concave, positioning for optical coupling is ensured and workability is improved. improves.

The optical path chamber 21 does not need to be cylindrical, but may be rectangular or the like.

[0032]

As is apparent from the above description, according to the first aspect of the present invention, the light emitting side single device and the light receiving side single device
The device is composed of two separately formed light shields, which are integrally molded with an exterior resin and fixed, so that even if the optical path between light receiving and emitting is long, optical coupling can be secured. The electrical insulation is improved. Moreover, the entry of disturbance light can be prevented by the exterior resin, and malfunctions and the like can be prevented. In addition, the light receiving and emitting light shields and the exterior resin are made of the same heat
Since it is made of plastic resin material,
Dissolve a part of the surface of both light shields, these primary mold
The resin interface between the body and the secondary mold body can be eliminated.
Therefore, resin destruction due to thermal expansion or thermal contraction, etc.
Can be prevented.

Further, since the operation of inserting both elements into the outer case as in the conventional example 2 can be omitted, manual work can be omitted and the production efficiency can be improved by automation.

According to the second aspect of the present invention, the thermoplastic resin
The material is polyphenylene sulfide (PPS), poly
Carbonate (PC), polybutylene terephthalate
(PBT), crystalline polymer, amorphous polymer, or
Is one or more of thermoplastic resins such as liquid crystal polymers.
These are mixtures that have high workability and high molding accuracy.
It is a high resin material and has excellent weather resistance.
Therefore, molding can be performed efficiently.

According to the third aspect of the present invention, since the insulation resistance of both the light-shielding body and the exterior resin is set to be large, an excellent effect that the insulation withstand voltage between light reception and emission can be increased to meet a predetermined standard can be obtained. is there.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical coupling device showing an embodiment of the present invention.

FIG. 2 is a process flow chart showing a method for manufacturing an optical coupling device.

FIG. 3 is a diagram showing a state in which each single device is arranged to face each other;

FIG. 4 is a diagram showing a state in which each light shield is formed.

FIG. 5 is a diagram showing a state in which both light shields are positioned.

FIG. 6 is a cross-sectional view of the optical coupling device of Conventional Example 1.

FIG. 7 is a process flow chart showing a method for manufacturing the optical coupling device of Conventional Example 1.

FIG. 8 is a cross-sectional view of the optical coupling device of Conventional Example 2 when the inner case is inserted.

FIG. 9 is a cross-sectional view after completion of the optical coupling device of Conventional Example 2.

FIG. 10 is a process flow chart showing a method for manufacturing the optical coupling device of Conventional Example 2;

[Explanation of symbols]

REFERENCE SIGNS LIST 11 optical coupling device main body 12 light emitting side lead frame 13 light emitting side single device 14 light receiving side lead frame 15 light receiving side single device 18 light emitting side light shielding body 19 light receiving side light shielding body 20 exterior resin 21 optical path chamber

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-283179 (JP, A) JP-A-3-19289 (JP, A) JP-A-3-203274 (JP, A) 27952 (JP, U) Shokai Sho 62-182561 (JP, U) Shokai Hei 3-104766 (JP, U) Shokai Hei 2-8156 (JP, U) (58) Fields surveyed (Int. Cl. ⁶ , DB name) H01L 31/12

Claims (3)

(57) [Claims] 1. A light emitting side unit molded with a translucent resin.
I and the body device molded in Yotsute integrally with the thermoplastic resin
Emitting light-shielding body that, received that is molded by translucent resin
Side single device Yotsute integrally molded thermoplastic resin
And a light-receiving side light-shielding member comprising:
Optical path chamber is provided for forming the optical path to the light receiving side unitary device from the side alone devices, both the light shield, the two unitary Device
An optical coupling characterized in that the chair is disposed so as to be optically coupled on substantially the same optical axis in the optical path chamber, and is integrally molded with the same light-shielding body with the same thermoplastic external resin. apparatus. 2. The material of the thermoplastic resin according to claim 1.
Is polyphenylene sulfide (PPS), polycarbonate
Bonate (PC), polybutylene terephthalate (PB
T), crystalline polymer, amorphous polymer, or liquid crystal
One or more of thermoplastic resins such as polymers
An optical coupling device , which is a mixture . 3. The insulation resistance of the thermoplastic resin according to claim 1 , wherein the insulation resistance is set to 10 ¹² Ω or more at a normal temperature of about + 25 ° C. and 10 ¹¹ Ω or more at a high temperature of about + 100 ° C. Characteristic optical coupling device.