JP3304387B2 - Optical 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 novel optical connector which reduces the emission of signal light from the end face of the optical connector when the connector is not connected.

[0002] An optical fiber is used for transmitting signal light. An optical connector is used to optically connect the optical fiber to various optical devices or optical fibers. Such an optical connector is provided with an optical fiber at the center, and it is indispensable to connect the optical connectors so that their axes are accurately aligned.

[0003] A semiconductor laser device is used as a light source of the signal light, and the emitted light and the optical fiber are optically connected to each other using the semiconductor laser device as a light source, and the laser signal light is transmitted through the optical fiber.
The optical signal light is transmitted and received at the end face of the optical connector in a state where the optical signal light is connected to another optical device or an optical fiber, but is emitted from the end face to a free space when the optical signal light is not connected.

[0004] Laser light has a high energy density due to its nature, and when signal light emitted from the optical connector into free space irradiates the human body, when it enters the eyes, it impairs the retina and is extremely dangerous. Great care must be taken to ensure that this does not happen.

[0005]

2. Description of the Related Art A conventional optical connector is shown in a sectional view of FIG. In the drawings, the left hand is referred to as the front and the right hand is referred to as the rear for convenience of description. A ferrule 2 is housed in the center of the inside of the connector housing 1. In the connector housing 1, the front half 3 and the rear half 4 are mutually connected and integrated by a screw portion 5.

[0006] A rubber bush 6 is fitted to the rear portion of the rear half body 4, which protects the optical fiber cord 7 against sudden bending. A compression coil spring 9 is interposed between the flange 8 of the ferrule 2 and the rear half 4 of the connector housing to urge the ferrule 2 forward. Part 10
At a constant pressure by a spring 9, and is positioned by this.

Outside the connector housing 1, a cylindrical nut 11 is formed at an intermediate portion of the inside thereof. A front surface of a ring portion 12 is engaged with a flange portion 13 of the front half 3 of the connector housing in front of the ring portion 12. It is configured as follows. A screw portion 14 is provided inside the front of the nut 11. A knurl 15 is formed on the outer peripheral surface of the nut 11 so that a rotating operation by hand can be easily performed.

The state of the conventional optical fiber cord and ferrule is shown in a sectional view of a ferrule assembly shown in FIG.
A holding bracket 18 for holding a ferrule 17 made of ceramic in which an optical fiber 16 is inserted at an accurate position inside the center is provided with an optical fiber cord 19 inside the adhesive 2.
At 0, it is adhesively fixed. The above-mentioned flange portion 8 is formed on the outer periphery of the holding bracket 18.

As shown in FIG. 7, a pair of the conventional optical connectors 21 is prepared, the ferrules 17 are opposed to each other, and a sleeve-shaped adapter 22 is disposed between the ferrules 17. The adapter 22 has a through-hole 23 formed therein that can be precisely fitted to the ferrule 17. A mounting flange 24 is provided at an outer central portion, and a male screw 25 that can be screwed with the screw portion 14 of the nut 11 on both sides thereof. Is formed.

The ferrule 17 is inserted into the through hole 23 from both sides of the adapter 22, and the nut 1 is inserted into the male screw 25.
1 is screwed. As a result, the end faces of the two ferrules 17 and 17 come into contact with each other, and the end 10 (FIG. 5) of the first half 3 of the connector housing 1 is
And is prevented from being pushed by the nut 11 any more.

In this state, the end faces of both ferrules 17 and 17 come into contact with each other, thereby compressing the spring 9 at the rear and retracting the ferrule 2 (FIG. 5). Therefore, the optical fibers can be optically connected to each other with an appropriate contact force without contacting with an excessive contact force.

[0012]

According to the above-described conventional optical connector connection structure, if one optical connector A in FIG. 7 is used as a signal light emitting side and the other optical connector B is used as a light receiving side, the signal optical connector A shown in FIG. If the optical connector A is disconnected while the optical fiber is being transmitted, and the end face of the ferrule is directly viewed, or the end face is carelessly directed toward the eyes, the eyes may be damaged.
For this reason, it is necessary to take care to remove the optical connector A at the same time as putting a blind cap on the optical connector A or to wear glasses for blocking the optical wavelength band of the laser light.

When the optical connector B is removed with the optical connector A attached to the adapter 22 and the through hole 23 of the adapter 22 is viewed, there is a similar danger. In such a case, it is necessary to provide a laser hazard prevention device on the opening side that automatically covers the opening of the adapter 22 by removing the optical connector B.

In the former case, it is necessary to prepare blind caps, glasses, etc., and it is troublesome to operate them each time. In the latter case, the laser hazard prevention device becomes complicated and large-scale. In addition, since the optical connector protrudes considerably from the opening end of the adapter 22, the operation of attaching and detaching the optical connector is troublesome, and the appearance is not preferable.

An object of the present invention is to provide an optical connector which solves the above-mentioned various problems in the related art.

[0016]

Means for solving the above-mentioned problems of the prior art is to provide an optical fiber in the center.
The fiber is exposed at the tip end of the fiber.
A first ferrule and a front ferrule.
Optical fiber in the center and the optical fiber
The second ferrule with the end of the bar exposed is connected
Optical connector arranged in series on the same axis inside the connector, and the above-described optical connector is connected to another optical connector to be optically connected.
The rear end face of the second ferrule is the front face of the first ferrule
Of the first and second ferrules
Optical connection is made between the first and second ferrules in a disconnected state.
Front the second ferrule so that the end faces of the rule are separated
An optical connector comprising a biasing means biased toward the optical connector. The first ferrule is an optical connector further comprising an urging means urged forward so as to be able to retreat in a connector-connected state.

The first ferrule and the second ferrule are optical connectors in which the second ferrule is housed in a common guide cylinder and held so as to be slidable in the axial direction.
Further, the urging means is a spring.

[0018]

According to the constitution of the present invention, since the second ferrule is urged forward so as to be able to move forward and backward, the optical connection is made closely in the connected state, and the first ferrule is connected in the disconnected state. This space is separated from the end faces of
Since the signal light emitted from the first ferrule is not in a reliable and sufficient optical connection state with the second ferrule, the light emitted from the second ferrule does not have a harmful light amount.

The fact that the first ferrule is biased so as to be able to retract in the connected state acts so as not to apply an unnecessarily large contact force to the end face of the ferrule in the connected state. The fact that the first ferrule and the second ferrule are accommodated in series in the common guide cylinder allows the optical connector to be reduced in size and improved in accuracy.

By using a compression coil spring as the spring of the urging means, sufficient reliability can be ensured for a long term in terms of quality.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the drawings and specific embodiments based on the constitutional summary.

FIG. 1 is a sectional view of a ferrule assembly according to a first embodiment of the optical connector of the present invention. In FIG. 1, for convenience of explanation, the left hand toward the figure is forward,
The right hand is described as backward. In the figure, reference numeral 51 denotes a first ferrule, and 52 denotes a second ferrule. Each of the first and second ferrules 51 and 52 is made of, for example, a ceramic material, but may be made of a metal. However, ceramic materials are preferred because of their excellent wear resistance.

The outer diameters of the first and second ferrules 51 and 52 are the same and are arranged in series on the axis of the optical fiber in a guide sleeve 53 which is a common guide cylinder, and are fitted precisely. In particular, the second ferrule 52 is freely slidable in the axial direction. Step portions 54 and 55 are formed on both sides of the opposing portion, and compression coil springs 5 are formed there.
6, the spring 56 is compressed by an appropriate length, and the restoring force urges the second ferrule 52 forward.

The rear end of the first ferrule 51 is fitted to a metal holding bracket 57 and is integrally connected. In the center of the front end face, an optical fiber wire 59 which is an optical fiber in the optical fiber code 58 is embedded and the end face is viewed. At the rear, an optical fiber cord 58 is adhesively fixed inside the holding bracket 57 with an adhesive 60.

An optical fiber 61, which is an optical fiber, is penetrated and fixed inside the center of the second ferrule 52, and both ends are optically polished. Note that the end face of the first ferrule 51 is also finished in the same manner. The second ferrule 52 extends sufficiently forward, and a circumferential groove is formed at a position appropriately separated from the front end of the guide sleeve 53, and a C-shaped ring 62 is fitted in this groove.

A stopper 63 is provided at the front end of the C-ring 62. The rear of the stopper 63 has a sleeve shape, and this portion covers the guide sleeve 53, and the rear end is screwed into the holding bracket 57 with a screw 64. Fixed.

With the above configuration, the spring 5
The forward urging force of the second ferrule 52 due to the restoring force of 6 is locked by the contact portion between the C ring 62 and the stopper 63, and further forward movement is prevented, and the position is determined. .

For this reason, the front end of the second ferrule 52 projects a predetermined length beyond the stopper 63,
The facing distance L between the rear end face of the ferrule 52 and the front end face of the first ferrule 51 is determined in a relationship described later.

A large-diameter flange portion 65 is formed on the front side of the holding fitting 57, and a step portion 66 is formed on the rear side of the flange portion 65. The ferrule assembly 50 is configured as described above. The configuration of the ferrule assembly 50 as an optical connector is as follows. This will be described with reference to the sectional view of FIG. In FIG. 2, reference numeral 50 denotes the ferrule assembly described with reference to FIG. Therefore, the second ferrule 52 protruding from the stopper 63 is shown at the front left side, the optical fiber cord 58 extending rearward at the right side, and the holding bracket 57 is seen at the center.

The optical connector assembly 70 includes the ferrule assembly 50 described above, and the ferrule assembly 5
A connector housing 71 for accommodating the “0.”

The connector housing 71 includes a front half 74 and a rear half 75, which are connected by screws 76 and integrated. The front end face of the flange portion 65 of the ferrule assembly 50 is the end 77 of the front half 74.
, And the rear end face is in contact with a compression coil spring 72 inserted between the rear end face 75 and the front end face.

Since the spring 72 is inserted in a compressed state by an appropriate length, the ferrule assembly 50 is urged forward by its restoring force. A rubber bush 78 is fitted to the rear of the connector housing 71 to protect the optical fiber cord 58 against sudden bending.

A cylindrical nut 73 is provided outside the connector housing 71, and a front surface of a ring portion 79 formed in an intermediate portion thereof is engaged with and brought into contact with a flange portion 80 of a front half 74 of the connector housing in front of the nut 73. It is provided and configured as follows. A screw portion 81 is provided inside the front of the nut 73. A knurl 82 is formed on the outer peripheral surface of the nut 73 so that a rotating operation by hand can be easily performed.

As shown in FIG. 3, a pair of optical connectors 70 of the present invention are prepared, the second ferrules 52 are opposed to each other, and a sleeve-shaped adapter 83 is arranged between them.
The adapter 83 has a through hole 84 at an intermediate portion inside the second ferrule 52 and a stopper 63 at both sides thereof.
A concave portion 85 for accommodating the same is formed. A mounting flange 86 is formed at an outer central portion, and a male screw 87 which can be screwed with the screw portion 81 of the nut 73 is formed on both sides thereof.

The stopper 83 of the optical connector 70 is inserted into the concave portion 85 from both sides of the adapter 83.
Guide and insert. As a result of this insertion, the end of the second ferrule 52 is inserted into the through hole 84, so that the end faces of the two ferrules 52 abut on each other, and the guide sleeve 53 is formed.
The second ferrule 52 is pushed in the rearward direction (FIG. 1).

As a result, the opposing end faces of the first ferrule 51 and the second ferrule 52 are brought into contact with each other and optical coupling is possible. That is, the facing distance L shown in FIG.
Becomes zero. In such a relationship, the aforementioned interval L
Is set.

By further pushing, the end 77 (FIG. 2) of the front half of the connector housing 71 is
And is fixed so as not to be pushed by the nut 73 beyond it.

Thus, all the ferrules 5
The end faces of the first and second 52 and 52 abut against each other, so that the spring
2 is further compressed slightly as appropriate. That is, after the spring 56 in the ferrule assembly 50 is compressed, the spring 72 of the optical connector 70 is further compressed than the initially set compression amount. In other words, the compression force of the spring 72 is greater than the compression force of the spring 56 to urge the ferrule assembly 50 forward with a larger force.

As a result, the front end face of the flange portion 65 is slightly separated from the end 77 of the stopper 63. However, the front end face of the stopper 63 does not come into contact with the bottom face of the concave portion 85 of the adapter 83, and a slight gap is provided between them. This is because the second ferrules 52, 52
It is necessary to ensure that the contact connection between the end faces is performed without fail.

Thus, the ferrule assembly 50
As a result, the end faces of the second ferrules 52, 52 come into contact with each other due to the restoring force of the spring 72, and do not contact with excessive contact force. Is performed.

As described above, both optical connectors are provided with the second ferrule 52, so that the optical connector 70 is in close contact with the first ferrule 51 when the optical connector 70 is connected. The transmission of the optical signal light is reliably performed in the optical connector 70, and the optical signal light is transmitted to the other optical connector 70 in the same manner.

When one of the optical connectors 70 is disconnected and disconnected, the first and second ferrules 51 and 52 are separated from each other, and as a result, the optical fiber 5 of the first ferrule 51 is removed.
The optical signal light emitted from the optical fiber 9 forms a space between the optical fiber 61 and the second ferrule 52, so that the optical signal light spreads into the space. Therefore, the emitted light incident on the optical fiber 61 of the second ferrule 52 is very small. Amount. In this state, the amount of light emitted from the second ferrule 52 to the outside is not harmful. Therefore, the facing distance L between the first and second ferrules 51 and 52 needs to be set in such a relationship.

As described above, both are connected to the second ferrule 5
The optical connector 70 having the optical connectors 2 and 52 can be configured so that the optical signal light is transmitted to any one of the optical connectors 70. A conventional optical connector may be combined with the output side as the optical connector of the present invention.

A second embodiment of the ferrule assembly according to the present invention will be described below with reference to the sectional view of FIG. In this figure, the left hand is the front and the right hand is the back, and the same parts as those in FIG. 1 are denoted by the same reference numerals as those in FIG.

In FIG. 4, the ferrule assembly 90
1, has a first ferrule 51, a second ferrule 52, and a guide sleeve 53, which is a common guide cylinder for guiding and holding the first ferrule 51 and the second ferrule 52 therein. 1 between the first ferrule 51 and the second ferrule.
The step faces 54 and 55 and the spring 56 are not provided, and the opposed end faces of the ferrule are all flat.

The rear end of the first ferrule 51 is held and fixed by a holding bracket 57, and an optical fiber cord 58 is provided inside.
Are bonded and fixed with an adhesive 60, and an optical fiber wire 59, which is an optical fiber inside the optical fiber code 58, is a first fiber.
Of the ferrule 51.

An optical fiber 61, which is an optical fiber, is housed and fixed at the center of the second ferrule 52, and is exposed at both end faces. A groove is formed around an intermediate portion of the second ferrule 52, and a C ring 62 is fitted therein. The front surface of the C ring 62 is positioned in contact with a stopper 63 disposed in front of the C ring 62,
Behind the stopper 63 covers the guide sleeve 53 a sleeve-like, rear end is fixed screw 64 Deneji write <br/> or are in the holding fixture 57.

The front end of the holding member 57 has a flange-like portion 6.
5 and a step portion 66 is provided on the rear surface side in almost the same manner as in FIG. Here, in the present embodiment, a compression coil spring 91 is disposed between the guide sleeve 53 and the sleeve-like portion of the stopper 63. The spring 91 has a front end in contact with the rear surface of the C-ring 62 and a rear end surface in contact with the bottom surface of the front recess 92 of the holding fitting 58. In this state, the spring 91 is slightly compressed, and the restoring force urges the second ferrule 52 forward. This urging force is applied to the spring 7 of the optical connector shown in FIG.
The second ferrule 52 is set to be compressed only after the end faces of the second ferrule 52 abut against the first ferrule 51.

With the above configuration, the ferrule assembly of this embodiment is the same as the ferrule assembly 50 shown in FIG.
By applying the same as above, exactly the same operation can be obtained. According to this embodiment, since the steps 54 and 55 are not formed between the facing ferrules, the fitting length between the guide sleeve 53 and the ferrules 51 and 52 can be made sufficient by this amount. Ferrule 51,
52 can be less inclined. However, the guide sleeve 53 and the stopper 63 shown in FIG.
The diameter can be reduced by minimizing the distance between the sleeve and the sleeve-shaped portion.

[0050]

As described above in detail, according to the optical connector of the present invention, the second ferrule is brought into close contact with the first ferrule in the connected state of the connector, and is separated forward in the disconnected state. The second ferrule is configured to be provided with an urging means that can be energized, so that the second ferrule can move forward and backward, so that the amount of optical signal light transmitted to the second ferrule in a disconnected state is extremely reduced. 2 has an excellent effect that the amount of light emitted from the end of the ferrule does not cause a dangerous state.

In addition to the fact that the second ferrule is urged forward so as to be able to advance and retreat as described above, the first ferrule is further provided with an urging means for urging the first ferrule so that it can advance and retreat. Since unnecessary contact force does not act on the contact surface of the ferrule, the reliability of the optical connection can be improved such that the end face of the optical fiber is not damaged.

The present invention includes the fact that the first ferrule and the guide cylinder which is the guide sleeve are integrally formed. However, the first ferrule and the second ferrule can be separately formed as a separate guide cylinder. By fitting the ferrule into the guide sleeve, the outer circumference of each ferrule can be formed into a straight circular shape having the same diameter, and the fitting accuracy with the guide sleeve can be improved.

The urging means includes all those having elasticity and a restoring force against compression. For example, rubber, a disc spring, and a diaphragm correspond. However, by using a spring having compression rebound, high safety and long-term reliability are ensured.

Various modifications and application examples of the optical connector of the present invention can be considered. The cylindrical nut is not limited to the screw connection of the embodiment, but may be a bayonet connection structure.
A one-touch detachable structure can be provided. Further, the present invention can be applied to connection with various optical devices instead of connection between connectors. As for the C-shaped ring, it is also possible to directly form the ring-shaped portion integrally with the second ferrule, and to fix the ring with a set screw.

As described above, the optical connector of the present invention has various excellent practical functions and effects, and is extremely useful when applied to a connection portion for signal light.

[Brief description of the drawings]

FIG. 1 is a sectional view of an optical connector according to the present invention (first embodiment of a ferrule assembly).

FIG. 2 is a cross-sectional view of the optical connector of the present invention (assembly completed).

FIG. 3 is an explanatory view of connection of the optical connector of the present invention.

FIG. 4 is a sectional view of an optical connector according to the present invention (second embodiment of the ferrule assembly).

FIG. 5 is a cross-sectional view of a conventional optical connector (completed assembly).

FIG. 6 is a sectional view of a conventional optical connector (a ferrule assembly).

FIG. 7 is a connection explanatory view of a conventional optical connector.

[Explanation of symbols]

 Reference Signs List 50 ferrule assembly 51 first ferrule 52 second ferrule 53 guide sleeve 54, 55 step 56, 72, 91 spring 57 holding fitting 58 optical fiber code 59, 61 optical fiber wire 60 adhesive 62 C ring 63 stopper 65 Flange-like part 70 Optical connector assembly 71 Connector housing 73 Nut 74 Front half 75 Back half 77 End 78 Bush 81 Screw 83 Adapter 84 Through hole 85 Concave part 88 End face 90 Ferrule assembly 91 Spring

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G02B 6/36-6/43 G02B 6/24

Claims (4)

(57) [Claims] An optical fiber is provided at the center and said light is
A first ferrule that exposes the end of the fiber,
It is located in front of the first ferrule and has an optical fiber in the center.
With an eyebar, the ends of the optical fiber are exposed at both end faces.
And the second ferrule are on the same axis inside the connector
An optical connector arranged in series, said second optical connector being connected to another optical connector to be optically connected;
The rear end face of the ferrule is pressed against the front end face of the first ferrule.
And between the optical fibers of the first and second ferrules.
Optical connection is made and the first and second ferrules are not connected.
Attach the second ferrule forward so that the end faces of the
Optical connector characterized by comprising comprises a biasing means which is energized. 2. The optical connector according to claim 1, wherein said first ferrule comprises a biasing means which is biased forward so as to be able to retreat in a connector-connected state. 3. A process according to claim, characterized in that above the first ferrule and the second ferrule is accommodated in a common guide tube the second ferrule is formed by slidably held in the axial direction
2. The optical connector according to 1 . 4. The optical connector according to claim 1, wherein said urging means is a spring.