JP2007212983A - Optical fiber connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make coupling between an adapter housing side and a ferrule housing side stiffer and secure so as not to be disengaged even under all condition, such as time passage changes, to perform connection in a short time, to facilitate reduction in size and increase in the density, and to reduce the number of components drastically for cost reduction. <P>SOLUTION: The number of components is reduce maximally, and in the coupling between the ferrule housing side and the adapter housing side, a coupling means for permitting rotation, by providing the ferrule housing with a rotation auxiliary window is adopted. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a novel configuration of an optical fiber connector for interconnecting optical fibers used for optical fiber communication and the like.

  In today's communication technology, optical fibers are increasingly used for signal transmission from the standpoints of a significant increase in communication capacity due to video distribution, communication stability, and safety. The use of optical fibers requires many components, including optical fiber connectors, which are indispensable for almost all optical fiber systems. Fiber optic connectors connect fibers to fibers to active devices that form part of a communication system such as radiation sources, detectors, amplifiers, repeaters, etc., or connect fibers to various passives such as switches, dividers, attenuators, etc. Used to connect the fiber to the device. The performance required for fiber optic connectors is to perform functions with minimal signal loss when connected, to be able to connect as soon as possible, and to mechanically connect connections in any working or natural environment. There are many items such as holding and protecting, reducing the number of parts, reducing cost, miniaturization, and easy density increase. Currently, SC type, FC type, MU type, Although many types such as the LC type are used, since there are advantages and disadvantages, development of more excellent connectors is underway.

For example, the SC type optical fiber connector (see Non-Patent Document 1), which occupies the most mainstream at present, corresponds to a 2.5 mmφ ferrule with the shape shown in FIG. 1, and the main part is an adapter housing 1 and a ferrule housing. 2, a sleeve 3, a ferrule 4, a flange 5, a compression spring 6, an optical fiber cord 7, and the like, and a similar and slightly smaller ferrule housing 2 side by hand inside the square adapter housing 1 side. When pushed and inserted, the ferrule 3 in the ferrule housing 2 is inserted into the sleeve 3 in the adapter housing 1 to align the optical axis, and the action of the compression spring 6 via the flange 5 press-fitted into the ferrule 4 is achieved. With the pressure applied, the ferrules can be pressed together in the sleeve, and at the same time a plastic molded product is applied to the engaging part. Plastic protrusion has a configuration of a one-touch push-pull system to be fitted with a spring acting on the undercut portion in use. Further, the FC type optical fiber connector (see Non-Patent Document 2) is compatible with a 2.5 mmφ ferrule, and a metal screw engagement is employed for engagement between the adapter housing side and the ferrule housing side. Further, the MU type optical fiber connector (see Non-Patent Document 3) corresponds to a 1.25 mmφ ferrule, is a push-pull method similar to the SC type, and has an LC type optical fiber connector (see FIG. 2). For example, refer to Patent Document 1), which corresponds to a 1.25 mmφ ferrule and adopts a push-pull method, but adopts a method of pushing down the trigger 8 to release the engagement between the adapter housing side and the ferrule housing side. There are features.
Japanese Patent Publication No. 2001-147345 JISC5973 (F04 type optical fiber connector) JISC5970 (F01 type single-core optical fiber connector) JISC5983 (F14 type optical fiber connector)

  In the above FC type optical fiber connector, metal connector is used on the adapter housing side and the ferrule housing side, and screw engagement is used, so the connector connection is reliable and heat resistance is excellent. However, there are problems such as time-consuming connection, difficulty in miniaturization, a large number of parts, troublesome manufacturing and increased costs. Also, SC type, MU type, and LC type optical fiber connectors all use push-pull detachable types, so it takes less time to connect and mainly uses plastic molded products. While it has the advantage of being able to manufacture products with complicated shapes at a lower cost, it has a large number of parts, making manufacturing cumbersome and increasing costs, and small plastic protrusions when connecting the adapter housing and ferrule housing The parts are connected by being fitted to the undercut parts, but there is a problem that the stress cracking property and the creep property, which are common disadvantages unique to plastics, are insufficient. That is, there is a risk of causing a fatal problem that the connection between the adapter housing side and the ferrule housing side is released due to a phenomenon that cracks or deformation occurs for a long time in a state where stress such as stress or environmental change is applied. In the future, the outer diameter of the ferrule has been reduced to about 0.8 mmφ or less, and progress has been made in the direction of further miniaturization and higher density. However, as the miniaturization progresses, the engaging portion becomes smaller. In general, glass fiber reinforced plastic is used to improve the stress cracking property, creep property, heat resistance, etc., which are common defects of the above-mentioned plastic molded products, and that this phenomenon tends to become prominent. However, there were also problems such as the high cost of raw materials and the shortening of the mold life.

  The present invention is intended to solve the problems of such a conventional configuration, and even when a plastic molded product is adopted as the main part, the coupling between the adapter housing side and the ferrule housing side is further strengthened. In order to make sure that it does not come off under any conditions such as changes over time, it can be connected in a short time, easily downsizing and high density, drastically reducing the number of parts, etc. The goal is to thoroughly reduce costs.

  In the present invention, in order to solve the above-mentioned problem, the number of parts is reduced to the maximum, and at the same time, a means for rotational coupling at a slight angle is employed for coupling between the ferrule housing side and the adapter housing side.

  By adopting the rotary coupling method, compared with the conventional method, the coupling between the adapter housing side and the ferrule housing side becomes firm and reliable, and there is no disconnection under all conditions such as aging, In addition, since it can be connected in a short time because it can be connected with a small angle of rotation, it can be easily reduced in size and increased in density. By making the raw materials usable, there are great effects such as a reduction in cost, and from the feature that the number of parts can be remarkably reduced, an effect such as high suitability as a field assembly type connector can be expected.

  FIG. 3 is a side sectional view of the optical fiber connector in a state where the adapter housing side and the ferrule housing side are coupled to each other, showing an example of the best mode for carrying out the present invention. The outer diameter of the cylindrical sleeve 3 at the center of the adapter housing 1 using a plastic or metal molded article having a substantially elliptical projection at the end of the cylinder having a square section in the middle of both sides. It is a slightly larger circular hole, and the zirconia or metal sleeve 3 is housed by providing a protrusion 17 for preventing it from slipping out with a backlash, and has the same outer shape. An elongated cylindrical SUS having a ferrule 4 press-fitted at its tip is formed in a cylindrical ferrule housing 2 having a regular square cross section using a plastic or metal molded product. Which metal flange 4 is accommodated, and a hole 10 for accommodating the core of the optical fiber cord is passed through the center of the flange 4, and a compression spring 6 made of SUS or the like hits the flange 11. The front is pressed and the ferrules to be connected are accurately positioned and pressed together in the sleeve 3, and the other end of the flange 5 is fixed with a metal or plastic screw It is desirable to provide a structure in which the boot 9 is firmly fixed by covering the protrusion 9 with heat-shrinkable rubber or resin, etc. together with the protrusion 12 fitted with the screw with good airtightness by providing the protrusion 12 by a method such as When carrying out the work of covering with heat-shrinkable rubber or resin, the inside of the boot 9 is filled with a solvent-free type adhesive or the like so that it is airtight. It is further desirable to protect the optical fiber cord for a long period of time in any environment by improving and preventing the disconnection and improving the bending strength. In the method of providing the protrusion 12, the screw fitting described above is used in the present invention. For example, a method may be employed in which a concave line is provided in the flange portion 5 and fixed with a shrink rubber having a protrusion on the inside.

  In FIG. 3, the adapter housing 1 is composed of two parts having the same shape, and is configured to be coupled at the joint 18, but there are numerous designs in the vicinity of the joint depending on the purpose of use. Although it is possible to employ adhesion such as adhesion or physical coupling such as screws and screws by providing a flange, it is desirable to employ physical coupling in terms of connection reliability, and the above-described embodiment However, in the present invention, the cross section of the outer shape in the vicinity of the center of the adapter housing 1 is not limited to this. For example, it is a polygon such as a pentagon, a hexagon, an octagon, or a circle. However, in the case of a circular shape in particular, it is desirable to provide a projection or the like for preventing slippage on the surface.

  FIG. 4 is a perspective view showing the engagement mechanism between the adapter housing 1 and the ferrule housing 2, where the central axis of the ellipse major axis of the engagement protrusion 14 having an elliptical cross section at the end of the adapter housing 1 The hole 16 is attached to the corresponding end of the ferrule housing 2 and has a slightly larger hole 16 similar to the elliptical cross section of the end of the adapter housing 1 in the same manner as described above. The shaft is provided toward the apex of the square, and when the engaging protrusion 14 is inserted into the hole 16 in the direction of the arrow and pushed into the stopper and rotated about 90 ° to the right, the rotation assist window 15 makes it smooth. It can rotate and can be engaged firmly.

  This engagement mechanism will be described in more detail. FIG. 5 is a cross-sectional view taken along the line AA of FIG. 3 showing the engagement portion in a state where the adapter housing 1 and the ferrule housing 2 are engaged. The shape of the substantially elliptical engagement protrusion 14 is preferably a shape in which two diapers corresponding to the corners of a regular square are overlapped in terms of engagement strength, and when rotated by 90 °, FIG. A strong connection is obtained by engaging the outer portion of the dotted line with the ferrule housing 2, but it is desirable to further provide a mechanism for preventing the return of rotation, and the sliding of the engagement protrusion 14 of the auxiliary rotation window 15 is desirable. By adopting a method of engaging with the moving surface after going up the slope with the protrusion 13 or the like, or a method of engaging with the slope while going down the slope, it will never come off under any conditions Coupling is possible.

  Recently, with the progress of FTTH, there is a demand for a connector that can be quickly assembled at the construction site. However, the configuration of the present invention has a feature that the number of parts is remarkably small. As an on-site assembly type connector that uses an agent, it is highly suitable for any surface that can be easily assembled in a short time, and is simply assembled on-site with two Ferrule housings and two boots assembled with one assembled adapter housing. Is possible.

It is a perspective view of the conventional SC type optical fiber connector. It is a side view of the conventional LC type optical fiber connector. It is a sectional side view of the optical fiber connector of the engaged state of this invention. It is a perspective view which shows the mechanism of engagement of this invention. It is AA sectional drawing of FIG. 3 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Adapter housing 2 Ferrule housing 3 Sleeve 4 Ferrule 5 Flange 6 Compression spring 7 Optical fiber cord 8 Trigger 9 Boot 10 Hole 11 Grow part 12 Projection part 13 Projection part 14 Engagement projection part 15 Rotation auxiliary window 16 Hole 17 Projection part 18 Junction

Claims (5)

    From the outer diameter of the cylindrical sleeve 3 to the center of the adapter housing 1 using a molded product having a cylindrical shape from the middle of both sides and having an engagement projection 14 having an approximately elliptical cross section at the end. A slightly enlarged circular hole is opened, the sleeve 3 is loosely stored and stored in a state where it does not come out, and a ferrule 4 is first provided in a cylindrical ferrule housing 2 whose one end is a regular quadrangular prism. A long and narrow cylindrical flange 5 that is press-fitted is accommodated, and a hole 10 that accommodates an optical fiber cord is penetrated in the center of the flange 5, and the compression spring 6 hits against the flange 11 to be connected by pressing. In the optical fiber connector configured to press-contact the ferrules 4 with each other in the sleeve 3, the center axis of the elliptical major axis of the engaging protrusion 14 whose end section of the adapter housing 1 is substantially elliptical is A corresponding one of the outer shapes of the ferrule housing 2 is attached toward the apex of the regular square. At the end of the ferrule housing 2, a slightly larger hole 16 similar to the corresponding elliptical cross-sectional shape is formed in the same manner as described above. The center axis of the major axis is directed toward the apex of the regular square, and the engaging projection 14 is aligned and inserted into the hole 16 and pushed in, and then a quarter turn makes the rotation auxiliary window 15 An optical fiber connector, wherein the engagement protrusions 14 are engaged together by allowing them to rotate together.   2. The optical fiber connector according to claim 1, wherein a cross section of an outer shape in the vicinity of the center of the adapter housing employs a polygon such as a quadrangle, a pentagon, a hexagon, and an octagon, and a circle.   By adopting a means such as providing a protrusion 13 on a portion of the sliding surface of the auxiliary rotation window 15 with the engaging protrusion 14, a return prevention mechanism configured to engage while descending a hill is adopted. The optical fiber connector according to claim 1 or 2.   A protrusion 12 is provided at the end of the flange 5 by screw fitting or the like, and a boot 9 using plastic or rubber is covered with the protrusion 12 and the optical fiber cord in an airtight manner. 4. The optical fiber connector according to claim 1, wherein the optical fiber connector is applied in a state in which an adhesive or the like has been applied thereto.   5. The optical fiber connector according to claim 1, wherein the optical fiber connector is used in a field assembly type optical fiber connector.

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