JP3024407B2 - Optical cable connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connector for an optical cable for connecting one or more optical cables in which an optical fiber in which a core wire composed of a core and a clad is covered with a silicon layer is covered with a sheath through a buffer layer. The present invention relates to a connector (hereinafter simply referred to as a connector), and particularly to a connector in which a reliable connection characteristic is maintained without instantaneous interruption even when a large shock or vibration is caused to improve the characteristic.

2. Description of the Related Art In recent years, in the field of electronic devices, an optical fiber is often used for a signal line connecting each device with an increase in the amount of information exchanged.
At the time of inspection, maintenance and inspection, etc., the optical fiber as a signal line is frequently switched or its connection is detached, so the bayonet type, which is easy to attach and detach, is used for the connector connecting the optical cables. It is becoming heavily used.

[0003]

2. Description of the Related Art FIG. 3 is a diagram schematically illustrating an example of a conventional connector configuration, in which (3-1) is a perspective view showing the configuration, and (3-2).
FIG. 4 is a sectional view showing an assembled state.

FIG. 1 shows an example of a connector for connecting one optical cable. The optical cable 1 (1 _{-1 in the} figure) located on the left side of the figure and the optical cable 1 located on the right side
Connector to connect the (1 _-2 in Figure) 2, fitting 28 to hold connection positioned between the connector body 21 and the respective connector body 21 to be mounted on the end of each respective light cables
It consists of

The inner optical cable 1 is an enlarged cross-sectional view extracted.
As shown in (a), an optical fiber 1c in which a core wire 1a composed of a clad including a core is covered with a silicon layer 1b is covered with an outer cover 1e via an elastic buffer layer 1d such as "aramid fiber". At the ends thereof, a core wire exposed area a and an optical fiber exposed area b each having a predetermined length are formed in advance.

The connector body 21 is provided with the optical cable 1.
A cable fixing tube 22 made of a sleeve-shaped metal pipe having an inner diameter substantially the same as the outer diameter of the optical fiber 1; and a through-hole 23a having an outer diameter substantially the same as the outer diameter of the optical cable 1 and through which the optical fiber 1c can smoothly pass along its central axis. An optical fiber holder 23 made of metal having a flange 23b on one end face of a pipe region in which a hole is drilled, and a bottomed pipe shape having an inner diameter slightly larger than the outer diameter of the flange 23b of the optical fiber holder 23 is provided on the bottom surface. A hole 24 through which the pipe area of the optical fiber holder 23 can pass with a margin.
a lock sleeve 24 in which a retaining groove 24b having an end piece as an opening is formed at one location on the opening side of the peripheral wall, and a cylindrical core-shaped core of the optical fiber 1c along its central axis. A ferrule 25 having a hole 25a through which only 1a can be formed, and a coil spring 26 having a diameter that can be inserted between the pipe area of the optical fiber holder 23 and the inner diameter area of the lock sleeve 24. ing.

The ferrule 25 has a hole 25a so as to coincide with the through hole 23a of the optical fiber holder 23.
It is fixed to the 23 flange surfaces by means such as bonding. Then, after inserting the cable fixing tube 22 into the outer diameter region of the optical cable 1, the above-mentioned optical fiber holder 23 in which the coil spring 26 and the optical fiber holder 23 are inserted in the pipe region in advance is used for the cable 1 described above. The optical fiber exposed area b and the core wire exposed area a are inserted into the optical fiber exposed area b from the pipe side, and are bonded and fixed to the holder 23 and the ferrule 25, respectively.
Further, while the cable fixing tube 22 is being moved to the boundary area between the outer diameter portion of the optical cable 1 and the end of the pipe area of the optical fiber holding member 23, the two are fixed by crimping by external pressure, whereby the connector body 21 shown It can be attached to the optical cable 1.

After the optical cable 1 and the optical fiber holder 23 are bonded and fixed, a ferrule 25 integrated with the holder 23 is provided.
By mechanically polishing the end face of the ferrule 25 together with the core wire 1a, the end face of the ferrule 25 and the core wire end face of the optical fiber 1c can be completely matched.

On the other hand, the connecting member 28 is formed of a metal pipe having an outer diameter that can be fitted in the inner diameter portion of the lock sleeve 24 and having a through hole 28a having a diameter along which the ferrule 25 can be smoothly fitted along its central axis. The length is slightly shorter than the length of the two ferrules.

A guide pin 29 having a head diameter slightly smaller than the width of the retaining groove 24b of the lock sleeve 24 is implanted at each of the positions near the both end surfaces.
Thus, after the connector body 21 described above is mounted by the above method to each end of the optical cable 1 _-1 and 1 _-2 connecting, connector 28
On both sides from it to engage the guide pins 29 of the connector body 21 the arrows A _1, A inserted Rotate the _two retaining the locking sleeve 24 in the groove 24b and the connector 28, the optical cable 1 _- may _{be 1} and 1 _-2 configure the connector 2 can be connected.

In such a connector, the optical fiber holder 23
Since the coil spring 26 itself receives a force in the direction of being pressed by each other, the end faces of the ferrule 25 and thus the end face of the core wire 1a can be brought into close contact with each other, so that reliable connection between the optical fibers can be realized.

[0012]

However, in the connector having such a structure, the ferrule 25 to which the optical fiber is fixed, and thus the optical fiber holder 23 and the optical cable jacket 1e are integrated via the cable fixing tube 22. Therefore, when a sudden shock or large vibration exceeding the pressing force between the holders 23 by the coil spring 26 is applied to the optical cable 1, instantaneous separation occurs between the core wires which are in close contact with each other, and the relative position is reduced. There has been a problem that a shift may occur, and as a result, a signal to be exchanged may be momentarily interrupted.

[0013]

An object of the present invention is to provide an optical cable comprising two or more optical cables, each of which has an outer cover covering one or a plurality of optical fibers in a lump with a buffer layer at least below the outer cover. The optical fiber comprises a connector body fixed to the outer sheath and a connector for positioning and connecting each connector body, and the optical fiber is fixed such that a core end face of the optical fiber projecting from the end of the optical cable is exposed to the ferrule end face. Each of the connector bodies, each of which is composed of an optical fiber holder and a lock sleeve movably mounted in the direction of the ferrule end face via a coil spring on the optical fiber holder, faces both ends of the connector. When the lock sleeve of each connector body is engaged with the connector and each connector body is fixed to the connector, the ferrule of each optical fiber holding device is fixed. An optical cable connector configured such that end faces thereof are in close contact with each other, wherein a connector body is fixed to the outer cover between the lock sleeve and the optical fiber holder, and the connector body is fixed to the lock sleeve and the optical fiber holder. This is achieved by an optical cable connector having a connector housing which can be engaged with only two coil springs including the above-mentioned coil spring and can move in the axial direction.

[0014]

In an optical cable in which an optical fiber is covered with a sheath through a buffer material, the buffer material region can be used as a lengthwise buffer material between the sheath and the optical fiber.

Therefore, in the present invention, the optical fiber holder 23 integrated with the optical cable jacket 1e and the ferrule 25 fixed to the optical fiber 1c are engaged via the coil spring via the cable fixing tube 22. Thus, shocks and vibrations are absorbed by the buffer layer 1d interposed between the optical cable sheath 1e and the optical fiber 1c.

Therefore, it is possible to eliminate the influence of the sudden shock or vibration added to the optical cable on the ferrule 25, and to configure a connector capable of suppressing the occurrence of instantaneous signal interruption without lowering the operability of the connector. it can.

[0017]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view for explaining an example of the configuration of a connector according to the present invention together with its operation. FIG. 1 (1-1) is a view showing the connector configuration of the present invention. It is a figure showing the state where it was connected.

FIG. 2 is a diagram showing another embodiment. Note that, in the drawings, the case of the connector described in FIG. 3 is used as an example, and therefore, the same target members and parts as those in FIG. 3 are denoted by the same symbols, and redundant description is omitted. .

[0019] In the FIG. 1 (1-1), the connector 3 for connecting the optical cable 1 _-2 positioned to the optical cable 1 ₁ and the right to the left end position, Figure 3 similarly to the end of each respective light cables It comprises a connector body 31 to be mounted and a connector 28 of FIG. 3 for holding and connecting the connector bodies 31 to each other.

[0020] Incidentally, each optical cable 1 _-1, 1 _-2 in the state where both Figure 3 the same terminal processing is performed. The connector body 31 includes a cable fixing tube 22 shown in FIG. 3, an optical fiber holder 32 having the same configuration as that shown in FIG. 3, a ferrule 25 shown in FIG. 3, a connector housing 33 accommodating the optical fiber holder 32,
It comprises a lock sleeve 34 having the same configuration as in FIG. 3, and two coil springs 35 and 36.

The optical fiber holder 32 has the same configuration as the optical fiber holder 23 described with reference to FIG. 3, but only the length of the pipe region equal to the outer diameter of the optical cable is equal to the length of the optical fiber holder. It is formed shorter than the tool 23,
A ferrule 25 is integrally fixed to the flange surface as in FIG.

The connector housing 33 is formed such that the coil spring insertion portion 33b and the flange 33c sequentially increase in diameter while minimizing the cable fixing portion 33a whose outer diameter is equal to the outer diameter of each optical cable. Is a hole 33d and an optical fiber 1c into which the optical fiber holder 32 can be inserted with a margin including the flange from the flange side.
Is coaxially formed with a hole 33e which can penetrate with a margin.

The retaining rings 331 and 332 can be attached to the cable fixing portion side end of the coil spring insertion portion 33b and the opening side end of the hole 33d by means of, for example, a screw.

On the other hand, a hole 34a is formed in the shape of a bottomed pipe whose inner diameter is slightly larger than the flange diameter of the connector housing 33 and through which a coil spring insertion portion 33b of the housing 33 can pass with a margin. Lock sleeve 34
The stopper groove 24b described in FIG. 3 is provided at one position on the opening side of the peripheral wall, as in FIG.

Therefore, after inserting the cable fixing tube 22 into the outer diameter region of the optical cable 1 as in FIG.
Insert the coil spring 36 and the lock sleeve 34 into the connector housing 33 to which the
Attach.

Next, after the housing 33 without the retaining ring 332 is inserted into the optical fiber area, an adhesive is applied to the tip and the core area of the optical fiber area, and the coil spring 35 is mounted. The optical fiber holder 32 is inserted together with the ferrule into the distal end of the optical fiber area, and the two are bonded and fixed, and the ring 331 is mounted.

Further, similarly to FIG. 3, while the cable fixing tube 22 is moved to the boundary area between the outer diameter of the optical cable 1 and the end of the cable fixing portion of the connector housing 33, they are fixed by crimping by external pressure. Required connector body 31
Can be attached to the optical cable 1 as shown.

Then, the connector body 31 is inserted from both sides of the connector 28 as in FIG.
The 24b and optical cable 1 _-1 and 1 _-2 connect connector 3 by engaging the guide pins 29 of the connector 28 (1
-2).

In this connector, a connector housing 33 fixed to the outer sheath 1e of the optical cable 1 via the cable fixing tool 22 is connected to the optical fiber holder 32 adhesively fixed to the optical fiber including the core wire and the housing 33. The coil springs 35 and 36 respectively engage with the lock sleeve 34 connected to the other optical cable 1 via the fixture 28.

Therefore, the optical fiber holder 32 is a coil spring.
Since force is applied in the direction in which the ferrules 25 are pressed against each other at 35, the end faces of the ferrule 25 can be brought into close contact with each other as in FIG. 3 so that reliable connection between the optical fibers can be realized, and the optical cable 1 is held by the coil spring 35. Even when a sudden shock or large vibration exceeding the pressing force between the tools 32 is applied,
The stress applied to 1e is absorbed by the coil springs 35 and 36, and the stress is not transmitted to the optical fiber holder 32 and the ferrule 25, so that the end faces are kept in close contact. Can be suppressed.

The connector 4 for connecting a plurality of in FIG. 2 to illustrate the case of a connector applied to an optical cable comprising an optical fiber and optical cable _11-2 located optical cable 11 _-1 and the right on the left side, like FIG. 1 The connector body 41 is attached to the end of each of the optical cables, and a connector 51 for holding and connecting the connector bodies 41 to each other.

Each of the optical fibers constituting the optical cables 11 _-1 and 11 _-2 has been subjected to the same terminal processing as in FIG. A connector main body 41 having substantially the same configuration as the connector main body 21 described in FIG.
And a ferrule 43, an optical fiber holder 44, a connector housing 45, a lock sleeve 46, and coil springs 47 and 48.

Among them, the cable fixing tube 42 is substantially similar to the cable fixing tube 22 of FIG.
It is formed so as to match the outer diameter of 11.
Further, both the ferrule 43 and the optical fiber holder 44 are formed and formed so that the respective optical fibers and the core wires can be bonded and fixed individually in parallel corresponding to the number of optical fibers constituting the optical cable 11. In particular, in this case, one or a plurality of ferrules 43 are provided on the contact surface with the other ferrule 43 in order to secure a relative positional relationship with the other ferrule 43. (One in the figure) guide pin 43a and guide hole 43b fitted in it
Are provided at respective corresponding positions.

Further, the connector housing 45, the lock sleeve 46, and the coil springs 47, 48 are substantially similar to the connector housing 33, the lock sleeve 34, and the coil springs 35, 36 in FIG. It is formed while maintaining a dimensional relationship corresponding to the size of the tool 44.

On the other hand, the connector 51 has a shape substantially similar to the connector 28 of FIG. 1, but has an inner diameter formed so that the ferrule 43 can be fitted with its outer diameter. Therefore,
Each of the optical cables 11 _-1 and 11 _-2 is assembled by assembling the constituent members in the order described with reference to FIG. 1, attaching the connector body 41 to the end of each optical cable, and then interposing the connecting tool 51 therebetween.
Can be configured to be able to be connected.

[0036]

As described above, according to the present invention, it is possible to provide a connector for an optical cable in which a reliable connection characteristic is maintained without causing an instantaneous interruption even when a large shock or vibration occurs, thereby improving the characteristic.

[Brief description of the drawings]

FIG. 1 is a view for explaining an example of the configuration of a connector according to the present invention together with its operation.

FIG. 2 is a diagram showing another embodiment.

FIG. 3 is a diagram schematically illustrating an example of a conventional connector configuration.

[Explanation of symbols]

3,4 cable connector 1 _-1, 1 _-2, 11 _-1, 11 _-2 cable 22,42 cable fixing tube 24b retaining grooves 25, 43 ferrules 28,51 connector 29 guide pins 31 and 41 connector body 32 , 44 Optical fiber holder 33,45 Connector housing 34,46 Lock sleeve 35,36,47,48 Coil spring 43a Guide pin 43b Guide hole 331,332 Retaining ring 332

────────────────────────────────────────────────── ─── Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 6/36 G02B 6/40 JICST file (JOIS)

Claims (1)

(57) [Claims] 1. A connector body fixed to one end of one of two optical cables, the outer cover of which covers one or a plurality of optical fibers in a lump with at least a buffer layer thereunder. And a connector for positioning and connecting each of the connector bodies, and an optical fiber holding fixture to which the optical fiber is fixed such that a core end surface of the optical fiber protruding from the optical cable end is exposed to the ferrule end surface. The connector bodies each comprising a lock sleeve movably mounted in the direction of the end face of the ferrule via a coil spring on the optical fiber holder, are disposed opposite to both ends of the connector, and the respective connector bodies are provided. The ferrule end faces of the optical fiber holders are brought into close contact with each other when the lock sleeve is engaged with the connector and each connector body is fixed to the connector. An optical cable connector, comprising: a connector body (31) fixed between the lock sleeve (34) and the optical fiber holder (32) to the outer sheath, and the lock sleeve (34) and the optical fiber. The holder (32) is provided with a connector housing (33) that can be moved in the axial direction by engagement with only two coil springs (35, 36) including the above-mentioned coil spring (35). An optical cable connector characterized by the following: