JP2958223B2 - Transmission type 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 a transmission type optical coupling device for detecting the presence or absence of an object on a passage without contact.

[0002]

2. Description of the Related Art A conventional technique will be described with reference to FIG. FIGS. 8A and 8B respectively show a transmission type optical coupling device according to a conventional example (hereinafter simply referred to as “optical coupling device”).
3 is a vertical sectional view and a plan view of FIG.

As shown in FIGS. 8 (a) and 8 (b), in a conventional optical coupling device, a light emitting element 1 and a light receiving element 2 which are arranged to face each other and these light receiving / light emitting elements are entirely covered. And the outer case 3 housed in such a manner.
1 'and 2' are leads of both elements. The outer case 3 is made of a light-shielding resin, and has light passing windows (slits) 4 and 5.

In the above configuration, the irradiation light from the light emitting element 1 passes through the slit 4, passes through the slit 5 through the passage 6 of the object, and then enters the light receiving element 2. The presence or absence of the object is detected based on whether or not the irradiation light is blocked in the passage 6.

[0005]

The conventional optical coupling device has a structure in which the light emitting and receiving elements 1 and 2 are arranged to face each other with the object passage 6 interposed therebetween as described above. Since the dimension in the direction is long, when this optical coupling device is used for an object detection unit or the like of another device, it may be an obstacle to downsizing of the device or the like.

As a solution to the above-mentioned drawbacks of the prior art, Japanese Patent Application No. 4-250975 (1992) filed by the present applicant has been proposed.
(Filed on Sep. 21, 2009). The transmission type optical coupling device (hereinafter, simply referred to as “optical coupling device”) will be described with reference to FIG. 9A and 9B are a vertical sectional view and a plan view of the optical coupling device, respectively. Note that the same symbols are given to the same functional portions as those in the conventional example shown in FIG.

As shown in FIGS. 9 (a) and 9 (b), in the optical coupling device of the prior application, a resin mold type light emitting element 12 and a light receiving element 13 are accommodated in a lower part of an outer case 11, and furthermore, both elements are formed. A light emitting side opening part 14 and a light receiving side opening part 15 for opening the light emitting surface side and the light receiving surface side of 12, 13 to the outside respectively are formed. 12 'and 13' are both elements 12,
13 leads.

The first light guide 1 that guides the irradiation light from the light emitting element 12 onto the passage 6 is provided above the outer case 11.
6 and a second light guide 17 that reflects light guided on the passage 6 by the first light guide 16 and guides the light to the light receiving element 12 is formed to protrude upward. Here, the outer case 11 is formed of a light-shielding resin.

The first light guide 16 and the second light guide 17
Are formed of a translucent resin, and both light guides 16 and 17 are
Is formed with a prism-shaped reflecting portion 18 so as to reflect the light L from the light emitting element 12. The thickness (d in the figure) of the light guides 16 and 17 is approximately equal to the slit width of the slits 4 and 5 of the conventional example shown in FIG.

The outer case 11 and the light guides 16 and 17 are integrally formed by multi-color molding.

The light emitting element 12 and the light receiving element 13 are conventional off-the-shelf products. The light receiving element 13 has a resin molded part formed of a visible light cut resin in order to prevent noise caused by disturbance light. ing. These two elements 12,
The fixing method of the outer case 11 to the outer case 11 is as follows.
Then, the housing is fixed with an adhesive, or the lower part of the light emitting / receiving element is heated from the outside of the outer case 11 so that a part of the outer case 11 protrudes inward and is fixed.

As described above, the optical coupling device of the prior application has a structure in which the object passage 6 is only sandwiched between the first and second light guides 16 and 17 having the prism-shaped reflecting portions 18. Therefore, compared to the related art, the direction of the optical path for detecting passage of an object (in the conventional example of FIG. 8, the arrangement direction of the light receiving and emitting elements) can be reduced.

As described above, the thicknesses of the first and second light guides 16 and 17 are the same as those of the conventional slits 4 and 5 shown in FIG.
Since the slit width may be about the same, the thickness can be reduced, and the portion through which the detected object passes can be remarkably reduced in size and thickness as compared with the related art, and it is possible to cope with a limited space.

Further, in the optical coupling device of the prior application, the leads 12 ′, 13 ′ of the light emitting / receiving elements 12, 13 are provided from the outer case 11.
The parts are protruding, and are easily attached to a substrate or the like, and handling is easy.

In addition, the optical coupling device of the prior application has a cost advantage because it can use a conventional light emitting and receiving element as it is.

However, in the optical coupling device of the prior application, when the shape of the light guides 16 and 17 is changed, for example, the detection position of the object to be detected is changed and the light guides 16 and 17 are changed.
Each time the length is changed, or when the thickness of the light guides 16 and 17 is changed so as to effectively utilize the light amount of the light emitting element, a new manufacturing mold is required each time. Here, the optical coupling device of the prior application generally includes a light emitting / receiving element 12, 1
3 and a light guide 16,
17 is integrally formed by multi-color molding, so that even if the shape of the mold is only the light guide portion, a shape including the outer case molding portion is required,
The mold area is large, complicated, and the cost is increased. That is, when changing the light guide shape,
A mold including the shape of the outer case molding portion that does not need to be changed each time is required, which causes waste.

The present invention has been made in view of the above problems, and provides a transmission type optical coupling device which is divided into an outer case portion and a light guide portion provided with both light guides, so that the shape of the light guide can be easily changed. It is intended for.

[0018]

According to a transmission type optical coupling device of the present invention, a resin mold type light emitting element and a light receiving element are juxtaposed and housed, and the light emitting surface side and the light receiving surface side of the two elements are respectively outwardly arranged. A light-shielding outer case, which is open to the outside, and a first light guide on the light-emitting side and a second light guide on the light-receiving side, which are disposed above the light-emitting element and the light-receiving element, and form an object passage. And at least one end of the one light guide,
A transmissive optical coupling device formed by forming a prism-shaped reflecting portion that guides light from the light emitting element to the light receiving element, wherein the first light guide and the second light guide are both light guides. A light guide is provided with a connecting portion for connecting the other end, and the light guide and the outer case are divided.

Further, the light guide section is attached to the outer case section as an adhesive or a cartridge type.

[0020]

According to the above construction, the transmission type optical coupling device according to the present invention comprises the outer case, the first light guide, the second light guide, and the connecting portion connecting the other ends of the two light guides. Since the light guide portion is divided into a plurality of light guide portions, a plurality of light guide portions provided with light guides having different shapes are provided in advance, so that each light guide portion has a light guide shape corresponding to a use. It can be easily changed to the light body part.

Further, a new mold for manufacturing in accordance with the change of the shape of the light guide may have a shape in which only the light guide is formed, and includes an outer case forming portion such as the transmission type optical coupling device of the prior application. No shape is required. Therefore, the mold area is small, the structure is easy, and the cost can be reduced because the outer case molding portion is unnecessary.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described with reference to FIGS. 1A and 1B are a plan view and a longitudinal sectional view, respectively, of a transmission type optical coupling device according to the present invention. FIG. 2 is an exploded view, and FIGS. 2A and 2B are longitudinal sectional views showing a light guide portion and an outer case, respectively.

This embodiment will be described only with respect to differences from the transmission type optical coupling device of the prior application shown in FIG.

As shown in FIGS. 1 and 2, the transmission type optical coupling device of this embodiment (hereinafter simply referred to as "optical coupling device").
Are the first light guide 16, the second light guide 17, the two light guides 16,
The light guide unit 20 includes a connecting portion 19 that connects the other end of the light guide element 17 and an outer case 11 in which a resin mold type light emitting element 12 and a light receiving element 13 are juxtaposed and housed.

The connecting portion 19 and the light guides 16 and 17 are integrally formed by multicolor molding to form a light guide 21. The connecting portion 19 may use either a light-shielding resin or a light-transmitting resin. Alternatively, the connecting portion 19 and the light guides 16 and 17 may be integrally formed by one-color molding using a light-transmitting resin.

The outer case 11 is used as a general-purpose product, and the light guide portion 20 is of a cartridge type that can be detached by engaging means (not shown) such as a hook. The body part 20 can be changed. Further, the light guide portion 20 may not be of a cartridge type, but may be attached with an adhesive.

The connecting portion 19 forms a part of the upper part of the outer case 11 in the optical coupling device of the prior application shown in FIG.

FIGS. 3 to 7 show the light guide section 20.
2 shows another structural example.

FIGS. 3 (a), 3 (b) and 3 (c) are longitudinal sectional views showing the structure when the detection position of the object is changed.

FIG. 3A shows the light guide 20 of the above embodiment.
FIG. 3B is used when the detection position of the object is set lower than that of FIG. 3. FIG. 3B is used when the detection position is set higher.
(C) is used when the operation direction of the detected object is set in a direction perpendicular to the operation direction of the detected object in the above embodiment.

FIGS. 4 to 7 are structural diagrams in the case where the light guide portion 20 is changed so as to effectively utilize the light amount of the light emitting element 12, and FIGS. 4 (a), 4 (b) and 4 (c). Are a front view, a plan view, and a right side view of the light guide unit 20, respectively.

The light guide portion 20 shown in FIGS.
The first and second light guides 16 and 17 have a shape that is thicker at a portion near the connecting portion 19 and gradually becomes thinner as approaching the reflecting portion 18 at the tip.

According to this structure, since the light guides 16 and 17 have a large area in contact with the light receiving and emitting elements 12 and 13, on the light emitting side, the light quantity of the light emitting element 12 is effectively utilized to guide the light to the tip. The light from the light emitting element 12 can be sufficiently transmitted to the entire light receiving surface of the light receiving element 13 on the light receiving side.

The light guide section 20 shown in FIGS.
This is an example in which only the thickness of the reflecting portion 18 at the tips of the first and second light guides 16 and 17 is reduced. According to this structure,
Since the portions other than the reflection portion 18 are formed thick, there is a slight restriction in space, but more reliable light transmission can be achieved.

The light guide section 20 shown in FIGS.
The two light guides 16 and 17 of FIG. 5 are provided with inclined surfaces that become thinner toward the ends, so as to take advantage of both the advantages of FIGS. 4 and 5.

The light guides 16 and 17 of the light guide portion 20 shown in FIGS. 7A to 7C are the reflection portions at the tips of the light guides 16 and 17 shown in FIGS. 6A to 6C. Among 18, 18, the tip which does not contribute much to reflection is cut to achieve further miniaturization.

The structure of the light guide 20 is not limited to the one described above, and may be a combination of FIG. 1 or FIG. 3 and FIG. 4 to FIG.

As described above, the optical coupling device of the present invention has the structure shown in FIG.
In the optical coupling device of the prior application shown in FIG.
And the outer case 11 are divided, and the outer case 11 is made into a general-purpose product, and both light guides 16 and 17 are connected by a connecting portion 19 to form a cartridge type. By providing a plurality of light guide portions 20 provided with light guides 16 and 17 having different shapes in advance, the light guide portion 20 having a light guide shape suitable for the intended use is provided. It can be easily changed.

Further, a new mold for manufacturing in accordance with the change of the shape of the light guide may have a shape in which only the light guide portion 20 is formed, and does not require the outer case forming portion as in the optical coupling device of the prior application. Become. Therefore, since the outer case molding portion is unnecessary, the mold area is small and the structure is easy, so that the cost can be reduced.

[0040]

As described above, according to the transmission type optical coupling device of the present invention, since the outer case portion and the light guide portion are divided, a plurality of light guides having different shapes in advance are provided. By providing the light guide, it is possible to easily change the light guide to a light guide having a light guide shape suitable for each application.

Further, a new manufacturing die for changing the shape of the light guide may have a shape in which only the light guide portion is formed. The shape including the portion is unnecessary. Therefore, the mold area is small, the structure is easy, and the cost can be reduced because the outer case molding portion is unnecessary.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of the present invention, and FIG. 1 (a) and FIG. 1 (b) are a plan view and a longitudinal sectional view, respectively.

FIG. 2 is an exploded view of the transmission type optical coupling device shown in FIG. 1,
(A) and (b) are longitudinal sectional views showing a light guide part and an exterior case part, respectively.

FIG. 3 is a longitudinal sectional view for explaining another example of the structure of the light guide.

FIG. 4 is a block diagram for explaining another structural example of the light guide.

FIG. 5 is a block diagram for explaining another structural example of the light guide.

FIG. 6 is a block diagram for explaining another structural example of the light guide.

FIG. 7 is a block diagram for explaining another structural example of the light guide.

FIG. 8 is a configuration diagram showing a conventional example, and FIGS. 8A and 8B are a longitudinal sectional view and a plan view, respectively.

FIG. 9 is a configuration diagram of the transmission type optical coupling device of the prior application, and FIGS. 9A and 9B are a longitudinal sectional view and a plan view, respectively.

[Explanation of symbols]

 Reference Signs List 6 Object passage 11 Light-shielding exterior case (part) 12 Light-emitting element 13 Light-receiving element 14 Light-emitting side open part 15 Light-receiving side open part 16 First light guide 17 Second light guide 18 Reflecting part 19 Connecting part 20 Light guide Department

Claims (2)

(57) [Claims] A light-shielding outer case in which a resin-molded light-emitting element and a light-receiving element are juxtaposed and housed, and a light-emitting surface side and a light-receiving surface side of the two elements are respectively opened outward; And a first light guide on the light emitting side and a second light guide on the light receiving side, which are disposed above each of the light receiving elements and form an object passage, at least one end of one of the light guides A transmission type optical coupling device formed by forming a prism-shaped reflecting portion for guiding light from the light emitting element to the light receiving element, wherein the first light guide and the second light guide are both light guides A transmission type optical coupling device, comprising: a light guide portion provided with a connection portion for connecting the other end of the light guide portion; and the light guide portion and the outer case portion being divided. 2. The transmission type optical coupling device according to claim 1, wherein the light guide is attached to the outer case portion as an adhesive or a cartridge type.