JPH0356444B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an optical branching path used as part of optical transmission technology using plastic fibers.

[Background technology]

2. Description of the Related Art In recent years, optical transmission technology using glass fibers has made remarkable progress in optical communication systems and the like. In addition to the above-mentioned glass fibers, plastic fibers are also available as optical fibers that serve as light transmission media, but their practical use has lagged behind that of glass fibers. Other components of optical communication systems that use plastic fiber as a transmission medium include optical connectors for connections, optical branchers, optical demultiplexers/multiplexers, optical switches, and optical modules (optical-electrical/electrical-optical converters). equipment) etc. are required. An optical branching path is used to distribute an optical signal propagating through one optical transmission path to multiple optical transmission paths, or to divide an optical signal propagating through multiple optical transmission paths, such as two, into one optical transmission path. It is a device that focuses.

As shown in FIG. 1, the conventional optical splitter for plastic fiber requires a case 1 to fix the adapters 2, 2, 2, and a branch block 5 with a branch path 6 is installed in the case 1. It is stored. The branch block 5 includes a branch road platform 7 on which the branch road 6 is mounted, and plastic fibers 3 extending from adapters 2, 2, 2 at both ends of the case.
It consists of positioning plates 8, 8 for positioning 3, 3. The positioning plates 8, 8 accommodate and support the plastic fibers 3, 3, 3 in grooves 8', 8', 8' formed on their surfaces, respectively, and
Each plastic fiber 3 is adhesively positioned on both sides of the branch road platform 7 in order to connect each plastic fiber 3 to each end face of the branch road 6. These positioning plates 8, 8 and the branch road platform 7 are adhesively fixed to the branch block fixing plate 4, and the branch block fixing plate 4 is further attached to the case 1.
Fixed. In addition, the branch block fixing plate 4
The plastic fibers 3, 3, 3 before being housed in the positioning plates 8, 8 are also adhesively fixed thereto. In the figure, 9 is an optical connector and 10 is an adhesive.

As mentioned above, conventional optical branching paths for plastic fibers (hereinafter referred to as "optical branching devices") have many parts and connections between the optical connector and the branching path, which takes time to assemble. He was stiff. In addition, there were many adhesive points such as the positioning plate and the branch block fixing plate, the plastic fiber and the branch block fixing plate, and the positioning plate and the branch road stand. Therefore, there were concerns about strength, poor workability, and unsuitability for automated manufacturing. Furthermore, a large number of connection points is undesirable because it may result in a large connection loss. Conventionally, a plastic fiber was used as a relay component between the adapter and the branch path, which increased the overall length of the optical branch. Also,
The end face of the plastic fiber had to be mirror-finished, and the mirror-finished portion caused connection loss. There is a slight gap between the plug tip of the optical connector and the plastic fiber in the adapter at the connection point between the two, but there is a risk that dirt or the like may get into this gap and cause connection loss. In addition, the method of connecting the branch road and the plastic fiber by adhering the positioning plate and the branch road platform is not a very preferable connection method because it has a large effect on connection loss when there is a misalignment in positioning. Conventionally, the cross section of the branch path has been square, resulting in a large connection loss between the branch path and the plastic fiber having a circular cross section.

[Purpose of the invention]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an optical branching device that is compact, takes less time to assemble, has less connection loss, and can connect and fix optical connectors easily and reliably. shall be.

[Disclosure of the invention]

In order to achieve the above object, the present invention provides a method in which a branch path for branching or combining light transmitted through an optical fiber is fitted into a groove provided in the joint surface of a molded body formed by joining two halves. In addition, a hole for collecting dust is formed at a position corresponding to the tip of each branching path on the joint surface, and a hole for collecting dust is formed on the side surface of the molded body from the position corresponding to the tip of the groove. A protruding portion serving as an adapter is formed, and a protruding portion is provided on the outer peripheral surface of each protruding portion to fit into a window provided in an adapter receiving portion of the optical connector and engage the optical connector. The main subject is optical splitters.

This will be explained in detail below with reference to drawings showing examples thereof.

As shown in FIG. 2, a molded body 11 made of plastic material or the like and having a total length approximately equal to the length of the branch path 6 is formed from two halves 11a and 11b. Adapters 14 for connecting to the optical connectors 9, 9, 9 are formed in half on both side surfaces of the two halves 11a, 11b perpendicular to the longitudinal direction. A groove (not shown in the drawing) for accommodating the branch path 6 is provided in the joint surface (inner surface) of both halves 11a and 11b, and the branch path is placed in the groove of one half body 11b. 6 is listed. adapter 14, 14,
14 and each tip of the groove are provided with holes 12, 12, 12 for collecting dirt.
Above the points 2, 12, and 12, the ends of the branch paths 6 are located. Furthermore, another hole 13, 13, 13 is provided slightly inside each of these tips, and serves as an adhesive reservoir when joining the two halves 11a, 11b.

When assembling an optical branching path having such a structure, first, as shown in FIG. 2, the branching path 6 is placed in a groove (not shown) in one of the halves 11b. Thereafter, the joining surfaces of both halves 11a and 11b are joined and fixed using an adhesive. At this time, the adhesive reservoir holes 13, 13, 13 provided in one half 11b are very convenient because the excess adhesive between the two joint surfaces flows into them. However, the method of joining both halves is not limited to adhesive bonding.
Other joining methods may also be used.

When the optical branch path according to the present invention is connected to an optical connector, the plug of the optical connector inserted into the adapter is directly connected to the branch path, so there are fewer connection points and connection loss can be reduced. It can be done. Further, since a hole is provided at the bottom of the connection point to serve as a dirt reservoir, it is possible to prevent loss due to dirt getting in between the connection points.

In the optical splitter according to the present invention, the branch path has a circular cross section. Therefore, since the cross-sectional shape is the same as that of the plastic fiber in the optical connector, connection loss due to the difference in shape can be eliminated.

In the optical branching device according to the present invention, the optical connector and the adapter are connected and fixed in the following manner. As shown in FIG. 3, the adapter receiving portion 15 of the optical connector 9a is provided with several elongated notches 16 extending inward from the cylindrical tip in the longitudinal direction, so that the width of the adapter receiving portion 15 is widened. It is designed to have flexibility. The peripheral surface of such an adapter receiving portion 15 is provided with windows 17, 17 at opposite positions. On the other hand, as shown in FIG. 4, the outer peripheral surface of the adapter 14a of the optical splitter is provided with bulges 18, 18 at opposite positions. Therefore,
When the optical branch adapter 14a is inserted into the optical connector 9a, as shown in FIG.
17, opposing bulges 18, 18 on the outer peripheral surface of the adapter 14a are fitted and locked from the inside.

Therefore, the optical branching device according to the present invention can be easily and reliably connected to the optical connector.

In the most common case, the molded body constituting the optical splitter according to the present invention, including the shapes of grooves, holes, etc. formed therein, can be simultaneously molded by injection molding using a synthetic resin material. Therefore, it is easy to manufacture and suitable for mass production.

The grooves, holes for dirt storage, and holes for adhesive storage formed on the joining surfaces of both halves of the molded product may be provided in both halves, or may be provided only in one half. do not have.

In the embodiment, the optical branching device according to the present invention was described as being for a branching path with a branching ratio of 1:1, in which the optical branches are branched by 50%. However, there are also many branching paths. For such branch paths, it is sufficient to mold a molded body with many grooves and adapters for storing the branch paths, depending on the number of branches.In the case of multiple branches, the molded body becomes large, so A dedicated branch adapter or optical connector may be provided.

〔Effect of the invention〕

As described above, the optical splitter according to the present invention is
A branch path for branching or combining light transmitted through the optical fiber is fitted and fixed in a groove provided in the joint surface of the molded body formed by joining two halves, and A hole for collecting dust is formed at a position corresponding to the tip of each branching path on the surface, and a protruding part serving as an adapter is formed on the side surface of the molded body from a position corresponding to the tip of the groove. A bulge is provided on the outer circumferential surface of each protruding portion to fit into a window provided in an adapter receiving portion of the optical connector and engage the optical connector. Therefore, the number of parts required for conventional optical splitters (more than 10) is three, which is extremely small, making assembly easier and faster, reducing costs, and manufacturing. This has the effect of making automation possible. Furthermore, since the plug of the optical connector and the branch path are directly connected, there is no need for a large number of connection points as in the conventional case, and the effect of reducing connection loss is also brought about. Furthermore, unlike the conventional method, there is no need for a plastic fiber for relaying, so the overall length is shortened, resulting in an overall compact design. Further, in the optical branching device according to the present invention, a protruding portion that is fitted into a window provided in an adapter receiving portion of an optical connector and engages the connector is provided on the outer circumferential surface of the protruding portion that becomes the adapter. Therefore, the connection and fixation with the optical connector can be easily and reliably performed.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional optical splitter, FIG. 2 is a perspective view showing each component and optical connector in an embodiment of the optical splitter according to the present invention, and FIG. 3 is an example of an optical connector. Representing side view, 4th
The figure is a partial side view showing one embodiment of the optical splitter according to the present invention, and FIG. 5 is a partially sectional side view showing the connection structure between the optical connector shown in FIG. 3 and the optical splitter shown in FIG. be. 6... Branch path, 9, 9a... Optical connector, 11
... Molded object, 12 ... Hole, 14, 14a ... Adapter.

Claims (1)

[Claims] 1. A branching path for branching or combining light transmitted through an optical fiber is fitted and fixed in a groove provided in the joint surface of the molded body formed by joining two halves, and A hole for collecting dust is formed at a position corresponding to the tip of each branching path on the joint surface, and a protruding part serving as an adapter is formed on the side surface of the molded body from a position corresponding to the tip of the groove. The optical splitter is provided with a bulge on the outer circumferential surface of each protruding portion, which fits into a window provided in an adapter receiving portion of the optical connector and engages the optical connector.