JPS61252510A - Optical fiber connector - Google Patents

Abstract

PURPOSE:To reduce a wear caused by an attachment and a detachment, by providing a mechanism for pressing a deforming action member against a terminal member, immediately before or immediately after the terminal member reaches a prescribed connecting position. CONSTITUTION:A spring base 5' is pushed in the direction separated from the center part of an adaptor by a coil spring 7, therefore, a holding force does not work on an FF ferrule 2'. Also, when a plug 17' is inserted, a part of the plug pushes a rear part 11 of the spring base immediately before a tip 3' of the FF ferrule reaches the center part, the spring base 5' slides and a tip 8' of a pressure spring slides down along a projection part 9' and a holding force is applied to the FF ferrule 2', and the tip reaches the center. A position where the holding force by the pressure spring starts to be applied to the FF ferrule can be set at the same time when the connecting end of the FF ferrule reaches the connecting position, or after it has reaches, by changing a distance L1 between the tip part of the pressure spring and the rear part of the spring base, or a distance L2 between the tip of the FF ferrule and the surface of the plug. In this way, a wear powder generated by an attachment and a detachment can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical fiber connector (hereinafter abbreviated as optical connector) for connecting optical fibers used as transmission media for optical communication.

(Prior Art) Optical fibers, which have excellent transmission characteristics such as broadband and low loss, have recently been used on a large scale as transmission media for information and optical energy. Along with this, there has been a need for a low-cost, easy-to-operate optical connector that can connect small optical fibers with a diameter of about 0.1 mm, which are used especially when transmitting high-speed information, with low connection loss.

Optical fiber connections require more advanced technology than electrical connections, mainly due to the small diameter and fragility of optical fibers. In other words, in order to connect optical fibers with less energy loss at the connection point, it is necessary to align the optical axes of the optical fibers to be connected, and to precisely align them on the micron order so as to eliminate gaps between the end faces of the optical fibers. (This is called optical axis alignment).

As a conventional optical connector structure, for example, Japanese Patent Publication No. 55-2
A structure in which a ferrule and a sleeve are basic elements as shown in No. 2707 is common.゛The ferrule protects the optical fiber, so it is rod-shaped and has a circular cross section, with a through hole for inserting the optical fiber with a diameter slightly larger than the outer diameter of the optical fiber made with precision on its central axis. It is a member having a cylindrical portion with high roundness, while the sleeve is a cylindrical member for accurately butting the ferrules together. Pass the tips of the pair of optical fibers to be connected through the through holes of the pair of ferrules, align the end surfaces of the optical fibers and the ferrules on the same plane, and fix them. Then, insert the pair of ferrules into the sleeve. Optical fibers are connected by inserting the ferrule and butting the end faces of the ferrules together. At this time, if the optical axes of the optical fibers are bent (referred to as angular misalignment) or misaligned with each other at the optical fiber connection portion, the connection loss increases. Therefore, in order to make a good connection with low connection loss, in the past, the ferrule and sleeve were precisely machined, and the ferrule, which was designed not to bend (called a rigid ferrule), was suspended from the plastic by a spring or the like (a floating structure). structure), and the holding force of the sleeve that tightens the ferrules is sufficiently strong to prevent mutual angular or axial misalignment of the ferrules.

This holding force is necessary to reliably and accurately align the ferrules with each other to make a connection with low connection loss, but on the other hand, when considering operability and reliability when connecting and disconnecting the connector, it is difficult to connect and disconnect the connector. Sometimes it's unnecessary force. In other words, increasing the holding force increases the frictional force between the sleeve and ferrule, which increases the wear associated with connecting and disconnecting the connector, and as the connector is repeatedly connected and disconnected, the dimensions and shape of the precisely machined ferrule and sleeve change, degrading their characteristics. There is a risk of Furthermore, in the connection of optical fibers, abrasion particles generated by wear affect the scattering of light and the alignment of the optical axis of the ferrule, which requires precision on the order of microns, causing an increase in connection loss. Furthermore, if the frictional force is large, the insertion/extraction force when attaching/disconnecting the optical connector also becomes large, which poses a problem when attempting to increase the number of fibers in the optical connector. In other words, the insertion/extraction force increases in proportion to the number of fibers, so
When an optical connector has multiple fibers, the insertion/extraction force becomes very large, and there is a risk that it will not be easy to operate.

Furthermore, the large insertion/extraction force applies a large force to the ferrule when the connector is attached/disconnected, and depending on the manner in which the connector is attached/disconnected, the ferrule may be subjected to excessive force and may be damaged.

(Problems to be Solved by the Invention) A highly reliable optical connector is achieved by realizing a structure that provides a reliable connection when attaching and detaching an optical connector and does not apply excessive force to the ferrule when attaching and detaching the connector. 1. By realizing a structure in which no holding force is applied to the ferrule when attaching and detaching the connector, damage to the ferrule is prevented, and wear caused by attaching and detaching the connector is reduced, resulting in an optical connector with excellent reliability. 2. By reducing the insertion and removal force when connecting and disconnecting the connector,
To provide an optical connector that has excellent operability and can easily be made to have multiple fibers.

(Means for solving the problem) The above problem can be solved by a separately pending application, which is characterized in that bending deformation of a practical size is possible with an appropriate amount of force, and that the deformation does not cause damage. (Special application 1844-1983)
40) terminal member for optical fiber connection, [hereinafter referred to as FF (Fl
The structure of the optical fiber connector was developed by using the structure of the optical fiber connector (exibie Fine) 7 z71z-71/] and the structure of the separately pending patent application (Patent Application No. 6O-23330), which is characterized by connecting by deforming the OFF ferrule. This can be achieved by using the structure shown in claim 1.

As already mentioned (Japanese Patent Application No. 6O-23330), the feature of optical connectors using FF ferrules is that even if the FF ferrule itself is fixed in a slightly shifted position, the tip of the FF ferrule can be flexibly deformed. This means that the connection ends of the connectors can be placed in precise positions, allowing connections with low connection loss. The force that is essential for realizing such a connection is the force exerted by a member called a deformation member.
This is a holding force for deforming the F ferrule, and by this holding force, the tip of the FF ferrule is placed on a reference plane for alignment called an alignment plane, and optical axis alignment is performed.

On the other hand, since the FF ferrule is easier to bend than the conventional ferrule, it is preferable that no holding force is applied to the FF ferrule at least when the connector is attached or detached, considering wear, damage, reliability, etc. during attachment and detachment as mentioned above.

The key point of the present invention is that when the FF ferrule is placed at a predetermined position on the joint surface (referred to as the connection position), no force is applied by the deformation member before the connection end face of the FF ferrule reaches the connection position, and the connection position is The purpose is to arrange the deformation effect member or the matching surface so that the force by the deformation effect member is applied to the tip of the FF ferrule immediately before or just after reaching the FF ferrule. That is, the objective is to realize a structure in which a holding force is not applied to the FF ferrule when the connector is attached or detached, but is surely applied when it is connected.

The present invention will be explained in detail below with reference to the drawings.

FIG. 1 is a partially sectional perspective view of an embodiment of the present invention. After inserting the plug, by operating an external lever, a spring base to which a pressing spring, which is a deformation member, is fixed is rotated, thereby applying a holding force to the FF ferrule.

The adapter 12' is connected to the FF ferrule 21. t2///■
A spring base 5' that fixes the pressing springs 1z and ltq for pressing against the groove 4' and is provided with a protrusion 23 for support during rotation and a guide portion 13' for the FF ferrule, and locking springs 157/II, 15 /////, an adapter body 16' provided with a matching groove 4', an FF ferrule guide portion 13"', and a recess for supporting a spring base. Also, a plug 17"' is the tip of the FF ferrule 3 to protect the flexible FF ferrule 2.
The plug body 18 has a structure that covers the area near ``'', and the FF
A ferrule 2, a ferrule spring 19' and a plug screw 20' for applying an axial force to the FF ferrule and semi-fixing it so that it slides in the axial direction, and a protrusion 25' for rotating the spring base. lock lever with
26'.

Before inserting the plug 17' into the adapter 12', the spring base 5' can rotate freely, so the holding force by the pressing spring 1'' is not working.
As the ferrule is inserted into the guide part 1, the ferrule tip 3''
3' and the guide part 13'', the guide part guides the ferrule into the groove 4', and it advances to the center along the groove 4'. As shown in Figure 2, since the protrusion 24 of the spring base 5' is not pressed down, the spring base 5' can still rotate freely, so the holding force by the pressing spring 1'' does not act on the FF ferrule 2. . After the tip 3 of the FF ferrule reaches the center of the adapter, by sliding the lock lever 26, the protrusion 27 of the lock spring of the adapter 12' engages with the locking protrusion 28 of the plug shown in FIG. .

Thereafter, by further sliding the lock lever 26, the protrusion 24 of the spring base 5' is pushed down and the spring base 5' is rotated, as shown in FIG. A holding force acts on the ferrule 2, and the tip 3 of the FF ferrule is pressed against the groove 4', making it possible to align the optical axis.Even if the base 22' of the FF ferrule is slightly shifted, the pressing spring 1'' is held The FF ferrule 2'' is deformed by the force, and its tip 3'''
(2) is pressed against the groove 4', making it possible to align the optical axis and realize a connection with low connection loss.

In this way, the above-described embodiment allows no force to be applied to the FF ferrule when the connector is attached or detached, and force can be applied just before the connector reaches the connection position.

In addition, even if the roots of FF ferrule and 2' are arranged with some deviation, the holding force of the pressing spring 1' deforms the FF ferrule and presses the tip 3' against the groove 4', making it possible to align the optical axis. Therefore, a connection with low connection loss can be realized.

Furthermore, in this embodiment, the holding force of the pressing spring is applied to the FF ferrule by rotating the spring stand to which the pressing spring, which is the deformation member, is fixed. However, instead of rotating the spring stand in this way, For example, as shown schematically in Fig. 4, a spring riding projection 9' is provided at an appropriate position, the spring base is moved parallel to the groove, and the tip 877N of the pressing spring slides down the projection. Also, as shown in Figures 5(a) and (b),
(2) A similar effect can be obtained by utilizing the step provided in the groove 4'.

Further, as schematically shown in FIG. 6, the pressing spring 1'', which is a deformation member, is placed perpendicularly to the V-groove 4' [FIG. 6(a)].
Alternatively, the same effect can be obtained by moving the pressing spring diagonally into the groove 4' (Fig. 6 (b)) or rotating it so that the tip 8w of the pressing spring draws an arc [Fig. 6 (C)]. It is possible to obtain.

Alternatively, instead of moving the deformation member, by moving the matching surface in the direction where force is applied to the FF ferrule,
It is possible to obtain similar effects.

Further, as described above, as a device for moving the deformation member or the matching surface, in the above embodiment, the plug is inserted into the adapter and the external member is manipulated after the tip of the FF ferrule reaches the center. Therefore, the structure is designed to apply a holding force, but for example, by using a surface perpendicular to the plug insertion/extraction direction, or by providing a wedge-shaped protrusion or a diagonal surface in the plug insertion/extraction direction, the plug can be simply inserted. It is also possible to create a structure that allows desired effects to be obtained.

FIG. 7 is a partially sectional perspective view of another embodiment of the present invention, in which a leaf spring (hereinafter referred to as a pressing spring) is used as the deformation member and a groove is used on the matching surface. . When the pressing spring 1 presses the tip 3 of the FF ferrule 2, the FF ferrule 2 is bent, and the tip 3 is pressed against the ■groove 4 and aligned by the alignment surface (■groove 4), making it possible to align the optical axis. Become. The pressing spring is arranged so that no force is applied by the pressing spring before the connection end face of the FF ferrule reaches the connection position, and the force is applied to the tip of the FF ferrule by the pressing spring just before or after reaching the connection position. The device for this purpose is a pair of spring stands 5.5' to which pressing springs 1.1' are individually attached, a guide groove 6 provided in an adapter that allows these spring stands to move back and forth, and a pair of a coil spring 7 placed between the spring bases 5 and 5', a protrusion 9' on which the tip 8' of the pressing spring rests, and a surface 11 of a part of the plug for pressing against the rear part 10 of the spring base. It is composed of

The adapter 12 includes: ■ a groove 4 for alignment and a continuous stand 14 provided with an FF ferrule guide portion 13.13', and pressing springs l and 1' for pressing the FF ferrule against the groove.
It consists of spring bases 5, 5' to which are fixed, a coil spring 7, locking springs 15, 15', 15', 15'', an adapter body 16 having a spring metal collecting groove 6 and a protrusion 9. .The structure of the plug 17' is similar to that of the plug body 18.
' is structured to cover the vicinity of the tip 3' of the FF ferrule in order to protect the flexible FF ferrule 2'.

The FF ferrule 2 is semi-fixed so as to slide in the axial direction by a ferrule spring 19 that applies an axial force to the FF ferrule inside the plug body 18 and a plug screw 20.

As the plug 17' is inserted into the adapter 12, the ferrule tip 3' enters the insertion hole 21' and the plug body 18
' and the adapter body 16 begin to engage, and the ferrule tip 3' is guided to the ■ groove 4 by the guide portion 13', and advances along the ■ groove 4 toward the center. At this time, as shown in FIG. 8, the spring base 5' is pushed in the direction away from the center of the adapter by the coil spring 7, so the tip 8' of the pressing spring fixed thereto is pushed into the protrusion 9. Therefore, no holding force acts on the FF ferrule 2'. As the plug 17' is further inserted, as shown in FIG. 9, just before the tip 3' of the FF ferrule reaches the center, a part of the plug presses the rear part 11' of the spring base, causing the spring to spring out. The base 5' slides, and the tip 8' of the pressing spring slides down the protrusion 9', causing the FF
A holding force is applied to the ferrule 2', and in this state, the tip of the FF ferrule reaches the center.

In this example, the position where the holding force by the pressing spring starts to be applied to the FF ferrule is set just before the tip of the FF ferrule reaches the center, but this position is between the tip of the pressing spring and the rear part of the spring base. By changing the distance L1 or the distance L2 between the tip of the FF ferrule and the surface of the plug that presses the spring base, the connection end of the FF ferrule can be set at the same time as or after reaching the connection position.

Further, in the above-mentioned embodiment, a spring is used as the deformation member, but as already disclosed (Japanese Patent Application No. 6O-23330), the spring is used instead of the spring as the deformation member.
Even if a protrusion or a convex portion of a curved member is used as a guide to bend the F ferrule into a predetermined shape, the desired effect can be similarly achieved by moving or rotating the deforming member as described above. It is possible to obtain

(Effects of the Invention) As explained above, the present invention takes advantage of the characteristics of the flexible FF ferrule, and provides an optical connector that is simple in structure and economical, and that takes advantage of the flexibility of the FF ferrule. This can be achieved with a structure that does not require force. Therefore, it is possible to prevent damage to the FF ferrule when attaching and detaching the connector, and it is also possible to reduce wear on the basic elements of the optical connector such as the OFF ferrule and groove when attaching and detaching the connector.
Furthermore, it is possible to reduce abrasion powder generated when the connector is attached and detached. This makes it possible to realize a highly reliable optical connector with less deterioration in characteristics due to attachment and detachment.

In addition to the feature of the optical connector connection method using the FF ferrule that allows connection even if the FF ferrule is fixed at a slightly shifted position, the feature of the present invention that the insertion/extraction force can be reduced makes it possible to connect multiple optical fibers. It is possible to realize a multi-core optical connector that simultaneously connects multiple fibers with low insertion/extraction force and good operability.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional perspective view of an embodiment of the present invention, FIGS. 2 and 3 are sectional views for explaining the operation of the embodiment shown in FIG. 1, and FIGS. Figures (a), (b) and Figure 6 (a),
(b). (C) is a schematic diagram illustrating a mechanism in which a holding force is not applied to the FF ferrule when connecting or disconnecting the connector, but is surely applied when connecting, and FIG. 7 is a partially sectional perspective view of another embodiment of the present invention. , FIGS. 8 and 9 are sectional views for explaining the operation of the embodiment shown in FIG. 7. 1, 1 z, 1 g, 1#/, 1////・
・・Press spring 2.2/, 21.2M, 2#/・・
・FF ferrule 3.3', 311.31M, 31
///...FF ferrule tip 4.4', 4'...
・■Groove 5.5', 5'...Spring base 6...Spring base guide groove 7...Coil spring 8.8', 8', 8'' g//l/...Press spring Tips 9.9', 9'... Spring riding projections 10, 10
'...Rear part of the spring stand 11.11'... Surfaces 12, 12 that press the rear part of the spring stand
'... Adapter 13.13', 13 ', 13''... Ferrule guide section 14... ■ Series 15.15', 15.15 .15 .15...
・Lock springs 16, 16'...Adapter body 17, 17', 17', 17"'...Plugs 18, 18', 18', 18"...
・Plug body 19.19', 19'...Ferrule spring 20.20', 20'...Plug screw 21.2
1', 21'... Ferrule insertion hole 22.22
', 22'... Root of the FP ferrule 23... Rotation support protrusion 24... Spring stand protrusion 25, 25'
... Lock lever protrusion 26.26'... Lock lever 27, 27'... Adapter lock spring protrusion 28.2
8'...Protrusion for locking the plug 29.29'...
Optical fiber 30.30'... Optical fiber core wire 31... Adhesive Figure 4 Figure 5 29-1-Force! Funai Iv Figure 6 (a) (C)

Claims (1)

[Scope of Claims] 1. A highly circular cylindrical portion having a through hole for inserting an optical fiber having a diameter slightly larger than the outer diameter of the optical fiber with high accuracy in the center; a pair of optical fiber connection end members whose portions can be elastically bent; a pair of deformation members for applying force to the tips of the end members to cause them to bend; In an optical connector having a matching surface composed of two planes for pressing the tip ends of a pair of terminal members and aligning the central axes of both terminal members, the optical connector is arranged opposite to the matching surface. The deformation effect member is rotatable or movable, a space in which the deformation effect member can rotate or a groove in which the deformation effect member can move, a member for rotating or moving the deformation effect member, and the deformation effect member within the space or the groove. By rotating or moving the terminal member with the optical fiber attached thereto, the terminal member is placed at a position on the matching surface where the optical fiber can be connected. An optical fiber connector characterized by having a mechanism that does not press the deforming member against the terminal member, but presses the deforming member against the terminal member immediately before or after the terminal member reaches a predetermined connection position. 2. In the optical fiber connector according to claim 1, the space is provided in the adapter having the matching surface, and the mechanism has a protrusion attached to the plug after mating the plug and the adapter. By operating a lock lever, the deformation member, which is attached to be rotatable around a predetermined position in the space, is pushed by a protrusion of the lock lever, rotated, and placed at a predetermined position. Features of optical fiber connectors. 3. In the optical fiber connector according to claim 1, the groove is provided in the adapter having the matching surface, and the mechanism is configured to insert the plug for attaching and holding the terminal member into the adapter, and The deformation effecting member in the adapter is pushed by the surface or protrusion that is disposed in the adapter to move it in a direction approaching the terminal member, and the spring placed between the pair of deformation effecting members disposed in the groove causes the deformation effecting member in the adapter to An optical fiber connector characterized by having a mechanism for moving the terminal effecting member in a direction away from the terminal member.