JP2007286354A - Optical connector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent PC connection impediment due to a defective end facing angle at the tip end face of the opposing ferrules, caused by a projection produced on the oblique ground surface of the ferrules. <P>SOLUTION: A recess for storing the projection produced on one oblique ground surface is provided on the other oblique ground surface, thereby constituting the optical connector, in a manner of preventing an end face angular change from being generated between the oblique ground surfaces of the pair of opposing ferrules. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an optical connector capable of collectively connecting a plurality of optical fibers, and more particularly to an improvement of an optical connector having a ferrule end face that is obliquely polished.

As an example of an optical connector for connecting an optical fiber ribbon having a multi-core optical fiber, an MT connector, an MPO connector, or the like is known.
The MT connector is, for example, FIG. 1 of Fujikura Technical Report No. 106 “Low Loss 24 Core MPO Connector” (pages 17-21, issued in April 2004), FIG. 1 of JP-A-9-178980, FIG. As shown in Fig. 1 of 1849442, the optical fibers fixed to the ferrules of the connector are placed opposite to each other and positioned with high accuracy through two guide pins, and both ferrules are connected via clamp springs. It is configured so that a constant pressing force can be maintained and maintained in a stable connection state.

    The MPO connector is described in the column “2.2-core MPO connector” on page 18 of Fujikura Technical Review No. 106 “Low-loss 24-core MPO connector” (pages 17-21, issued in April 2004) and FIG. As disclosed in Japanese Patent Application Laid-Open No. 10-170764, etc., there is no need for the alignment agent and the tool that are required for the MT connector, and the connector can be easily attached and detached with only one connector. Are known.

  These MT connector and MPO connector are provided with a ferrule which is a main component to which the lead portion of each optical fiber is fixed, and a clamp spring or a connector housing in which the ferrules are arranged to face each other and are mounted from the outside. It is configured to be pressed from the rear end portion of the ferrule toward the front end surface via a spring built in the inside.

The front end surface of each ferrule is obliquely polished at approximately 8 degrees, and when the obliquely polished surfaces are brought into contact with each other, the ferrule is arranged so that the center line thereof is linear.
This is because the oblique polished surfaces are brought into contact with each other and the optical fibers are brought into contact with each other, and increase in connection loss due to Fresnel reflection is controlled without a refractive index matching agent to realize PC (Physical Contact) connection.

  On the other hand, this ferrule is made of PPS resin or epoxy resin, and the PC connection state of the ferrule end face is as shown in FIGS. 4 and 5, and the oppositely polished ferrule end face is a spring for pressurization. When pressed in the axial direction, due to the clearance between the guide pin P and the guide hole 2 of the guide pin, the opposing ferrules slide in the direction of the arrow along the inclined surface, and an axial deviation occurs. . For this reason, a shearing stress acts between the guide pin P and the edge (edge) of the guide pin guide hole 2, and when this stress acts as a repetitive stress, the raised portion protrudes from the edge of the guide hole 2 due to plastic deformation. Q is generated.

The raised and projecting deformed portion Q presses the end face of the opposite ferrule, thereby creating a minute gap between the diagonally polished surfaces that are in close contact with each other, and this obstructs the connection of the PC (Physical Contact). There is a problem.
Japanese Patent Laid-Open No. 10-206690 Fujikura Technical Review No. 106 “Low Loss 24-Core MPO Connector” (Pages 17-21, April 2004)

  The problem to be solved is that the shear stress generated between the guide pin and the edge (edge) of the guide pin guide hole acts as a repetitive stress, and the guide pin guide hole edge of the ferrule made of resin is used. A raised protruding part is generated, and this prevents PC (Physical Contact) connection.

    According to the present invention, a notch groove that can effectively accommodate a raised portion generated by shearing stress is communicated with the edge portion of the guide pin guide hole at the edge portion of the guide pin guide hole on the oblique polishing surface that is pressed and maintained in close contact with each other. The main feature is that it is engraved on the ferrule end face.

  According to the present invention, since the protruding portion that rises between the guide pin and the edge portion of the guide pin guide hole is completely accommodated in the notch groove, the protruding portion obstructs the PC (Physical Contact) connection. There is an advantage that nothing is done.

  An optical connector incorporating a ferrule having a guide pin guide hole perforated in the longitudinal direction of the ferrule and an obliquely polished tip surface, which is non-diagonal from the edge of the guide pin guide hole exposed on the oblique polished surface A groove-like depression is formed on the ferrule tip surface toward the polishing surface.

    FIG. 1 shows an embodiment of the present invention. A guide pin guide hole 2 drilled from the front end surface of a ferrule 1 through a side edge of the ferrule and an adhesive filling formed on the surface of the ferrule 1. A plurality of insertion holes 4 that are inserted into the hole 3 and the adhesive filling hole 3 to insert the tip of the optical fiber, and an oblique polishing surface 5 formed on the tip surface of the ferrule 1 and a non-obliquely polished surface that is not obliquely polished 6 is well known, and the features of the present invention are as follows.

  That is, in the vicinity of the entrance of the guide pin guide hole 2, a recess 7 is formed which communicates with the entrance, and the recess 7 extends in a groove shape along the ferrule tip surface 5 which is obliquely polished. The groove-shaped recess is configured to communicate with the ferrule upper surface 8.

The groove-like recess is configured to communicate with the ferrule upper surface 8 toward the non-obliquely polished surface side 6. This can avoid that the depth of the groove of the recess becomes shallow due to the inclination as compared with the case where the groove-shaped recess is formed toward the oblique polishing surface side.
The width of the groove-like recess is preferably equal to or larger than the diameter of the guide pin guide hole 2.

  The operation and effect of the present invention will be described with reference to FIG. 3. When a pair of ferrules pressurize and hold the ferrule 1 in the longitudinal direction by a pressurizing means such as a clamp spring, the slant polishing surface slides relatively along the slope, and the guide A shearing stress acts in the vicinity of the guide pin guide hole edge in contact with the pin P, and when this is repeated, a protruding portion Q is generated due to plastic deformation, but it is formed at the guide pin guide hole edge of the opposing diagonal polishing surface. The recessed part which accommodates this protrusion part Q accommodates. For this reason, the projecting portion Q does not press the mating oblique polishing surface to change the position.

  The raised portion protruding in this manner is configured to enter a recess formed in the vicinity of the edge of the guide pin guide hole 2, and this raised portion presses the diagonally polished surface of the opposing ferrule to face each other. Since no minute gap is generated between them, the PC contact is not hindered.

    In the first embodiment, the end of the recess 7 itself extends to the upper surface 8 of the ferrule 1 as it is, but instead of this, a mortar shape is formed around the entire guide pin guide hole 2 as shown in FIG. Once the recess 9 is formed, another groove can be formed continuously with the mortar-shaped recess.

  Further, the groove-like recess 7 shown in FIG. 1 and FIG. 2 is extended and formed until it reaches the ferrule upper surface 8, but instead of reaching the ferrule upper surface 8, the recess ends in the middle. It may be.

      The present invention can be applied to either a ferrule for MT connector or a ferrule of MPO connector, and the arrangement of the optical fiber insertion holes 4 drilled in the tip surface is not limited to one row but can be applied to a plurality of rows. Needless to say.

The perspective view which shows 1st Example of this invention The perspective view which shows 2nd Example of this invention Longitudinal sectional view showing the implementation status of the present invention A longitudinal sectional view showing the implementation status of a conventional optical connector A longitudinal sectional view showing the implementation status of a conventional optical connector

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ferrule 2 Guide pin guide hole 3 Adhesive filling hole 4 Optical fiber insertion hole 5 Obliquely polished surface 6 Non-inclined polished surface 7 Recessed part 8 Ferrule upper surface

Claims (4)

  An optical connector in which a pair of ferrules each having a guide pin guide hole drilled in the longitudinal direction of a ferrule and an obliquely polished tip surface are pressed and held so that the obliquely polished surfaces are in close contact with each other, An optical connector in which a recess is formed at an edge of a guide pin guide hole exposed on a polished surface.   The optical connector according to claim 1, wherein the recess is extended in a groove shape along the oblique polishing surface.   The optical connector according to claim 1, wherein the recess is extended in a groove shape along the oblique polishing surface, and the groove-like recess communicates with the upper surface of the ferrule on the non-oblique polishing surface side. The optical connector according to any one of claims 1 to 3, wherein a diameter of the recess is equal to or greater than a diameter of the guide pin guide hole.

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