JPH11119057A - Optical connector plug - Google Patents

Abstract

(57) [Problem] An object of the present invention is to easily and surely connect ferrules, and to surely maintain connection between ferrules even after ferrule connection. SOLUTION: In an optical connector plug 2 according to the present invention, a ferrule accommodating space S is formed to be wide at the front end side of the housing 10 and narrow at the back side of the housing 10, and to have an outer wall surface 12 a of the ferrule 11 and an inner wall surface 10 of the housing 10.
a of the housing 1
It is a configuration that is gradually increased toward the front of 0.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connector plug for achieving ferrule connection by guide pins.

[0002]

2. Description of the Related Art Conventionally, as a technique in such a field, there is JP-A-63-139306. The optical connector described in this publication is a push-pull type optical connector, in which a plug having a coil spring for resiliently supporting a ferrule disposed in the front end of a housing (insertion guide) and a pair of plugs are inserted. By inserting a pair of left and right plugs into the through hole from both sides of the adapter.
The ferrules of each plug are connected via two guide pins. The plug connection is released by extracting the plug from the adapter. Further, the optical connector has an ejector which surrounds the housing and is urged by a spring, and adopts a configuration in which the ejector is engaged with a tab portion of the adapter, thereby enabling a one-touch structure. For example, a conventional optical connector 100 is shown in FIG.
The plug 101 has a ferrule housing 102 in the form of a sleeve.
A ferrule 103 is built in the front end portion of the coil 2, and the ferrule 103 is urged forward by a coil spring 104. Such a plug 101 is connected to the adapter 10
The connection between the ferrules 103 in the adapter 105 is achieved by inserting the through holes 105a from both sides in the adapter 105. In this case, the ferrule 103 has a predetermined clearance with the ferrule housing space 10 of the housing 102.
6 and held in a floating state within the housing 102. Therefore, when the plug 101 is attached or detached, the cord 11 of the housing 102 or the optical fiber 107 is not attached.
Even if a force is applied to zero, the influence on the ferrule 103 can be reduced as much as possible.

[0003]

However, since the conventional optical connector plug is configured as described above, there are the following problems.

That is, the plug 101 is connected to the housing 1
Since the ferrule 103 has a floating structure in which the ferrule 103 can move relative to the ferrule 103, if the clearance between the housing 102 and the ferrule 103 is too large, the ferrule 103 can easily move inside the housing 102 when the ferrules 103 are joined to each other. The guide pin 108 cannot be fitted into the guide pin hole 109 due to the inclination. Also, in order to increase the connection reliability between the ferrules 103,
If the clearance amount is reduced, the behavior of the housing 102 and the cord 110 in the bending direction is changed by the ferrule 103.
This causes a problem in that an excessive force is applied to the ferrule 103 after the plugs 101 are connected to each other, and an external force acts on the connection end face 103a of the ferrule 103 in the shearing direction, thereby causing an increase in connection loss.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. In particular, the present invention has been made to easily and surely connect ferrules, and to maintain the connection between ferrules even after ferrule connection. An object of the present invention is to provide a plug for a connector.

[0006]

According to the first aspect of the present invention, there is provided a plug for an optical connector according to the present invention, wherein the plug for an optical connector is viewed from an opening on the outlet side of a ferrule housing space provided at a front end of a ferrule housing. Has a ferrule resiliently supported outward, forming a predetermined clearance between the inner wall surface of the housing and the outer wall surface of the ferrule forming the ferrule receiving space, and the ferrule is formed within the housing. In the optical connector plug for holding the ferrule in a floating state and connecting the ferrules via the guide pin, the ferrule housing space is formed wide at the front end side of the housing and narrow at the back side of the housing,
The clearance formed between the outer wall surface of the ferrule and the inner wall surface of the housing is gradually increased toward the front of the housing.

[0007] In this optical connector plug, the ferrule accommodating space has a wide opening on the exit side and a narrow rear side, and the clearance between the ferrule and the housing is increased by the opening on the exit side. Therefore, when the plugs are connected to each other with the guide pin interposed therebetween, even if an external force in the bending direction is applied to the housing, the inner wall surface of the housing hardly collides with the outer wall surface of the ferrule, and the external force is transmitted to the ferrule. The situation is extremely small. As a result, in the connected state of the plug, a force in the shearing direction is less likely to be generated at the connection end face of the ferrule, and the optical connection state can always be kept constant.

[0008] In this case, the inner wall surface of the housing in the ferrule accommodating space is formed by surrounding the four sides with a flat surface, and the outer wall surface of the ferrule is formed by surrounding the four sides with a flat surface. Preferably, the wall surface forms an inclined surface facing each outer wall surface of the ferrule, and each inclined surface is preferably disposed around the ferrule. When such a configuration is employed, an unreasonable load is not applied to the ferrule against bending in all directions applied to the housing.

It is preferable that a stepped contact surface is formed on the inner wall surface of the housing to be engaged with a front end surface of a flange provided at a rear portion of the ferrule. When such a configuration is adopted, the flange portion of the ferrule can be pressed against the contact surface of the step portion of the housing when the plugs are not connected to each other, so that the step-shaped contact surface is used as a reference surface. The positioning of the ferrule within the housing can be facilitated, and the reliability of the plug connection can be increased.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a plug for an optical connector according to the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view showing an optical connector.
The optical connector 1 shown in FIG. 1 is a push-pull type optical connector. That is, by simply pushing the pair of plugs 2 and 3 into the adapter 4, plug connection with the adapter 4 interposed is achieved with one touch. When the ejector (knob) 5 provided on the plug 2 and the ejector (knob) 5 provided on the plug 3 are pulled out while being pinched by a finger, the plugs 2 and 3 can be easily removed from the adapter 4. Hereinafter, the structures of the plugs 2 and 3 and the adapter 4 will be described.

As shown in FIGS. 2 and 3, the plug 2 is
It has a ferrule housing 10 in the form of a sleeve made of plastic, and a plastic ferrule 11 is accommodated in the housing 10. Specifically, a ferrule housing space S having a rectangular cross section is formed at the front end of the housing 10, and a square pillar-shaped ferrule main body 12 is housed in the ferrule housing space S. Also,
A flange 13 is provided at the rear end of the ferrule 11, and a front end surface 13 a of the flange 13 is provided on the inner wall surface 10 of the housing 10.
a is in contact with the step-shaped contact surface 10b formed in the step a.

Further, the plug 2 has a hollow holder 14 fixed to the rear end of the ferrule housing 10. A pin clamp member 15 is disposed in front of the holder 14, and the pin clamp member 15 clamps the rear end of the guide pin P that has penetrated the ferrule 11. Then, the pin clamp member 15 is connected to the ferrule 1.
The pin clamp member 1 is brought into contact with the
5 and the holder 14 are separated from each other, and the coil spring 16 for pressing the ferrule is disposed at this portion. As a result, the ferrule 11 is elastically supported forward by the urging force of the spring 16, and the front end face 13 a provided on the flange 13 of the ferrule 11 is provided on the contact surface 10 b provided on the inner wall surface 10 a of the housing 10. Pressed.

When the stepped contact surface 10b is used as a reference surface, the positioning of the ferrule 11 in the housing 10 is reliably achieved, and the front end of the ferrule 11 is connected to the outlet side opening 17 of the ferrule housing space S. The ferrule 11 can be securely held by the housing 10 in such a state that the part can be slightly viewed. The guide pin P is disposed in a pin insertion hole 9 penetrating in the longitudinal direction (coupling direction) of the ferrule 11, and the tip of the guide pin P protrudes from the connection end face 11 a of the ferrule 11.

Further, the plug 2 is provided with a sleeve-shaped ejector 5 located on the outer periphery of the housing 10 and the holder 14.
The ejector 5 slides in the longitudinal direction of the housing 10. The ejector 5 is elastically supported forward by a coil spring 18 for the ejector. Specifically, the coil spring 18 is disposed between a spring receiver 19 fixed to the rear outer peripheral surface of the holder 14 and a projection 5a formed on the front inner peripheral surface of the ejector 5, and moves the ejector 5 forward. It is energizing. As a result, when the ejector 5 is retracted while being pinched by a finger, the ejector 5 is retracted against the spring force of the coil spring 18, and
When the finger is released, the ejector 5 moves forward by the spring force. In the vicinity of the tip of the ejector 5, the housing 10
A claw fitting recess 20 for engaging with a claw portion 23 (see FIG. 4) of the adapter 4 is formed on the outer wall surface 10c of the adapter 4.

A plurality of (for example, four or eight) optical fibers 8 are embedded in the tape core 7, and the tape core 7 extends from the rear end of the ferrule 11, and the tape core 7 extends.
Extend outside through the plug 2. A boot 21 is fixed to the rear of the plug 2.
1 protects the tape core 7 and prevents the tape core 7 from being bent at the end of the plug 2.

As shown in FIG. 4, the adapter 4 for receiving the plug 2 having such a structure has a through hole 25 for inserting the housing 10 of the plug 2 therein. Is a plastic protective cover 2
2 is formed. On the inner wall surface 22a side of the protective cover 22, a pair of claw portions 23 having a spring property extend in the plug insertion direction in a cantilevered state over the entire length of the through hole 25. At the tip, a convex portion 24 that engages with the claw fitting concave portion 20 of the plug 2 is formed. The projections 24 are formed at both ends of the claw 23.
This is because the plug 2 and the plug 3 (see FIG. 1) are to be inserted from both sides of the through hole 25 of the adapter 4 respectively.

Next, the connection between the plug 2 and the plug 3 via the adapter 4 will be briefly described. The plug 3 has substantially the same configuration as the plug 2 and will be described with the same reference numerals.

First, as shown in FIG. 5, the plug 2 is inserted from one side of the through hole 25 of the adapter 4 and the adapter 4 is inserted.
, And the ferrule 11 of the plug 2 is positioned in the adapter 4. Thereafter, as shown in FIG. 6, when the plug 3 is inserted from the other side of the through hole 25 of the adapter 4, the guide pin P provided on the ferrule 11 of the plug 2 is changed to the pin insertion provided on the ferrule 11 of the plug 3. It enters the hole 9. Then, as the plug 3 is pushed into the adapter 4, the ejector 5 continues to be retracted against the spring force of the coil spring 18 while the end of the claw portion 23 hits the ejector 5.

Thereafter, as shown in FIG. 7, the protrusion 24 provided at the tip of the claw 23 is engaged with the claw fitting recess 20 of the plug 2.
At the same time, the ejector 5 is released from the claw 23, and the ejector 5 returns by the spring force of the coil spring 18, and presses the projection 24 of the claw 23 from above. As a result, the claw portion 23 of the adapter 4 and the housing 1 of the plug 3
0 and the plug 3 with respect to the adapter 4
Is achieved. At the same time that the retaining is completed, the ferrule 1 of the plug 2 is
1 and the end face of the plug 3 with the ferrule 11 are completed.

When the plug 2 is inserted into the adapter 4, the same assembling operation as described above is performed. When removing the plug 2 and the plug 3 from the adapter 4, when the ejector (knob) 5 is pulled out while pinching it with a finger, the pressing of the claw 23 by the ejector 5 is released, and the plugs 2 and 3 are easily removed from the adapter 4. Can be removed.

Here, the plug 2 with the adapter 4 interposed
In order to make the connection between the plug and the plug 3 smooth, a floating structure that allows the ferrule 11 to be moved within the housing 10 is adopted for each of the plugs 2 and 3. That is, as shown in FIG. 8, the ferrule 11 is housed in the ferrule housing space S of the housing 10 with a predetermined clearance. In this case, the ferrule accommodation space S is wide at the front end side of the housing 10 and the housing 10
Is formed narrower on the back side of. Specifically, the clearance C formed between the outer wall surface 12a of the ferrule main body 12 of the ferrule 11 and the inner wall surface 10a of the distal end portion of the housing 10 is gradually increased toward the front of the housing 10.

Further, the inner wall surface 10a of the housing 10 in the ferrule housing space S is formed by surrounding the four sides with a flat surface, and the outer wall surface 12a of the ferrule main body 12 in the ferrule 11 is surrounded with the four flat surfaces. It is formed by doing. Further, each inner wall surface 10a is formed as an inclined surface facing each outer wall surface 12a of the ferrule 11, and by arranging each inclined surface 10a around the ferrule 11, the entire peripheral surface of the ferrule main body 12 is formed as each inclined surface. Surrounded by 10a. For example, ferrule accommodation space S
In the outlet opening 17, the clearance L between the outer wall surface 12a of the ferrule main body 12 and the inner wall surface 10a of the housing 10 is set to about 300 to 600 μm, and the inclination angle α of the inner wall face 10a is preferably set to about 3 to 6 degrees. is there.

As a result, as shown in FIG. 9, even when an external force in the bending direction X is applied to the housing 10 and the boot portion 21 in a state where the plug 2 and the plug 3 are connected with the guide pin P interposed therebetween, The inner wall surface 10a of the ferrule 1 hardly collides with the outer wall surface 12a of the ferrule body 12, and the ferrule 1
The situation in which an external force is transmitted to 1 is extremely reduced. Therefore, in the connection state between the plug 2 and the plug 3, a force in the shearing direction is less likely to be generated at the connection end face 11a of the ferrule 11, and the optical connection state can always be kept constant. In addition, the entire peripheral surface of the ferrule body 12 is
When the ferrule 11 is surrounded by “a”, an unreasonable load is not applied to the ferrule 11 for bending in all directions applied to the housing 10 and the boot 21.

[0025]

The plug for an optical connector according to the present invention is configured as described above, and thus has the following effects. That is, the ferrule housing space is formed wider at the front end side of the housing and narrower at the back side of the housing, and the clearance formed between the outer wall surface of the ferrule and the inner wall surface of the housing gradually increases toward the front of the housing. By doing so, the connection between the ferrules can be easily and reliably performed, and the connection between the ferrules can be reliably maintained even after the ferrule connection.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an optical connector to which a plug according to the present invention is applied.

FIG. 2 is a cross-sectional view of the plug shown in FIG. 1 taken along the line II-II.

FIG. 3 is a cross-sectional view of the plug shown in FIG. 1, taken along line III-III.

FIG. 4 is a partially cutaway sectional view of the adapter.

FIG. 5 is a partially cutaway sectional view showing a state where one plug is inserted into an adapter.

FIG. 6 is a partially cutaway sectional view showing a state in which the other plug is being inserted into the adapter.

FIG. 7 is a partially cutaway sectional view showing a state where both plugs are completely inserted into the adapter.

FIG. 8 is an enlarged sectional view of a main part of the plug according to the present invention.

FIG. 9 is a cross-sectional view schematically showing a state where a plug is inserted into the adapter.

FIG. 10 is a sectional view showing a conventional optical connector.

[Explanation of symbols]

S: ferrule accommodation space, C: clearance, P: guide pin, 1: optical connector, 2, 3, plug, 10: housing, 10a: inner wall surface (inclined surface) of housing, 10
b: contact surface, 11: ferrule, 12: ferrule body, 12a: outer wall surface of ferrule, 13: flange, 13a
... Front end face of the flange, 17 ... Exit side opening.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshiaki Kakii 1, Tayacho, Sakae-ku, Yokohama-shi, Kanagawa Prefecture Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Masaaki Takaya 3-9-1, Nishishinjuku, Shinjuku-ku, Tokyo No. Nippon Telegraph and Telephone Corporation (72) Inventor Shinji Nagasawa Nippon Telegraph and Telephone Corporation

Claims (3)

[Claims] The ferrule has a ferrule which is resiliently supported outward in the ferrule receiving space so as to be seen from an outlet side opening of a ferrule receiving space provided at a front end portion of a ferrule housing. Forming a predetermined clearance between the inner wall surface of the housing and the outer wall surface of the ferrule forming the ferrule housing space, holding the ferrule in a floating state in the housing, and guiding the ferrules to each other with a guide pin. In the optical connector plug for coupling via, the ferrule housing space is formed wide at the front end side of the housing and narrow at the back side of the housing, the outer wall surface of the ferrule and the inner wall surface of the housing, Between the clearance, gradually toward the front of the housing An optical connector plug, characterized in that the listen. 2. The inner wall surface of the housing in the ferrule receiving space is formed by surrounding four sides with a flat surface, and the outer wall surface of the ferrule is formed by surrounding all sides with a flat surface. And the inner wall surfaces are
2. The optical connector plug according to claim 1, wherein an inclined surface is formed to face each of said outer wall surfaces of said ferrule, and each of said inclined surfaces is arranged around said ferrule. 3. A stepped contact surface which engages with a front end surface of a flange provided at a rear portion of the ferrule is formed on the inner wall surface of the housing. 2. The plug for an optical connector according to 2.