JPH05188241A - Method for inserting ferrule for optical connector and its device - Google Patents

Abstract

PURPOSE:To provide the new method for inserting a ferrule for an optical connector which can rapidly, easily and surely insert an optical fiber into the ferrule and its the device. CONSTITUTION:The optical fiber 12 is inserted down into an optical fiber insertion hole 15 of the ferrule 14 for the optical connector and a cylindrical body 6 is so put on the ferrule 14 for the optical connector as to enclose the ferrule in the state. Compressed air 8 is thereafter passed into the cylindrical body 6 from the front end side of the ferrule 14 for the optical connector to insert the optical fiber 13 positioned in the optical fiber insertion hole 15 of the ferrule 14 for the optical connector into the positioning hole 17 of the ferrule 14 for the optical connector by the air pressure of the compressed air 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for inserting a ferrule for an optical connector into the tip of an optical fiber.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 3, a generally known ferrule a for an optical connector has an optical fiber strand b exposed at the tip of an optical fiber e by removing the coating from the tip. It has a small-diameter positioning hole c for inserting and positioning it correctly, and an optical fiber insertion hole d having a relatively larger diameter than the positioning hole c at the rear end thereof. d has a cylindrical shape connected inside. Also, this positioning hole c
The center axis of the is precisely drilled so as to be correctly aligned with the center axis of the outer diameter of the ferrule a, and is slightly larger than the outer diameter of the optical fiber element wire b. Similarly, the optical fiber insertion hole d is drilled with high precision so that its central axis is exactly aligned with the central axis of the outer diameter of the ferrule a and is slightly larger than the outer diameter of the optical fiber e. Has been done.

Then, as shown in FIG. 4, the optical fiber e is inserted into the ferrule a until the optical fiber strand b penetrates through the positioning hole c, and the optical fiber insertion hole d is previously filled with the adhesive. It is inserted and fixed with the agent f or the like. still,
At this time, the connecting portion between the positioning hole c and the fiber insertion hole d is formed in a tapered shape. Conventionally, as an apparatus for inserting an optical fiber into the ferrule a for an optical connector having such a structure, FIG. There was something like that shown in 6. First, in the device g shown in FIG. 5, an optical fiber fixing base j for attaching the optical fiber e is erected at one end of the base i, and a ferrule fixing base k for attaching the ferrule a is erected at the other end to fix the optical fiber. The optical axis e of the table j and the center axis of the ferrule a are aligned. Also, the ferrule fixed base k
Is fixed to a movable table m that can move in the axial direction of the optical fiber e on the straight guide rail l, and this movable table m is driven by being connected to a linear actuator (not shown).
Then, the optical fiber e and the ferrule a are attached to the optical fiber fixing base j and the ferrule fixing base k, respectively, and the ferrule fixing base k is moved to the optical fiber fixing base j to insert the optical fiber e into the ferrule a. It is a thing. However, in this device g, when there is a slight axial deviation or angular deviation between the axis of the optical fiber e and the central axis of the ferrule a, the optical fiber wire b is tapered at the entrance of the positioning hole c of the ferrule a. There was a defect that it was caught in the part and was broken. Moreover, since the insertion operation is a mechanical pushing operation by the moving table m, even if the optical fiber element wire b is broken during the insertion, the insertion operation is continued, so that the broken optical fiber element wire b There is also a problem that the ferrule a cannot be reused because it is clogged inside the ferrule a.

On the other hand, the device h shown in FIG. 6 was proposed in order to improve these problems, and although the basic structure is the same, the ferrule fixing base k is arranged in the axial direction of the optical fiber e. It is fixed to a slidable slide n, and this slide n
Is guided by a linear guide rail l ', which is different from the device g in that the linear guide rail l'is connected to a linear actuator (not shown). The device h is similar to the device g in that the optical fiber e is inserted into the ferrule a by the pushing operation of the moving table m, but the optical fiber strand b is positioned in the positioning hole c of the ferrule a.
If the sliding table n can be retracted when it is caught at the entrance of the optical fiber, that is, the taper portion, the disconnection of the optical fiber element wire b can be avoided.

Further, as in Japanese Patent Laid-Open No. 1-138531, there has been proposed a device similar to the device g shown in FIG. 5 provided with a sensor for detecting the backward movement amount of the sliding base n.

[0006]

However, the basic operation of inserting the ferrule a in the device h shown in FIG. 6 is the same as that of the device g shown in FIG. 5, and the optical fiber strand b is the ferrule a. In the case where the sliding table n is retracted and escapes from the disconnection when it is caught at the entrance of the positioning hole c, it does not mean that the optical fiber element b can be easily inserted into the positioning hole c. If the optical fiber e cannot be inserted by the single insertion operation, the optical fiber e may be reattached to the optical fiber fixing base j, or the optical fiber e may be easily inserted while the moving base m is moving. Since b has to be rotated, there is a problem that work efficiency is extremely poor.

Therefore, the present invention has been devised in order to effectively solve the above-mentioned problems, and an object of the present invention is to newly insert an optical fiber into a ferrule easily in a short time and surely. Another object of the present invention is to provide an optical connector ferrule insertion method and device.

[0008]

Next, according to the present invention,
We examined what kind of situation would occur when inserting an optical fiber into a ferrule. First, the ferrule was filled with an adhesive, the optical fiber was inserted into the ferrule, the insertion operation was stopped in the state of being caught on the way, the adhesive was cured, and then the ferrule was cut vertically to investigate the caught state. FIG. 7 shows a state of the connecting portion o between the optical fiber insertion hole d and the positioning hole c in the ferrule, and as shown in the figure, the optical fiber wire b is positioned in the positioning hole c.
On the other hand, it was found that there was a catch in the inclined state.

Therefore, the approach angle of the optical fiber element wire b which can be inserted into the positioning hole c was geometrically analyzed. FIG. 8 shows a state in which the optical fiber strand b has entered the positioning hole c with an inclination. The approaching state of the optical fiber strand b shown by the solid line in the figure is the limit state in which the optical fiber strand b can be inserted into the positioning hole c, and the approaching angle θ at this time is expressed by the following equation (1). ..

[0010]

[Equation 1]

If the angle of approach is larger than this, the state shown by the broken line in the figure occurs, and the optical fiber strand b cannot be inserted into the positioning hole c. That is, it has been clarified that unless the angle of approach of the optical fiber strand b to the positioning hole c is controlled to be ± θ or less, reliable insertion cannot be achieved only by pushing the ferrule. As a result, it is possible to correct the position of the ferrule according to the approach angle θ, but it is extremely difficult to detect the approach angle of the optical fiber strand b inside the ferrule.

In order to achieve the above object, the first method of the present invention is to provide a small-diameter positioning hole at the tip for correctly positioning the optical fiber strand exposed from the tip of the optical fiber. In addition to having an optical fiber insertion hole having a relatively large diameter at the rear end, the method of inserting an optical connector ferrule in which the positioning hole and the optical fiber insertion hole communicate with each other into the optical fiber, The optical fiber is inserted into the optical fiber insertion hole of the ferrule for an optical connector, and in that state, the ferrule for an optical connector is covered with a tubular body so as to surround the ferrule, and then the optical connector is placed in the tubular body. Compressed air is caused to flow from the tip direction of the ferrule for use in the optical fiber, and the optical fiber element is positioned in the optical fiber insertion hole of the ferrule for optical connector by the air pressure of the compressed air. The is intended to inserted into the positioning hole of the ferrule for the optical connector, the second inventive method,
The flow of the compressed air causes the ferrule for optical connector to rotate or vibrate. Further, the third invention device has a positioning hole of a small diameter for correctly positioning the optical fiber strand exposed from the tip of the optical fiber, and inserts a relatively large diameter optical fiber at the rear end. An optical connector ferrule inserting device for inserting an optical connector ferrule having a hole, wherein the positioning hole and the optical fiber inserting hole communicate with each other inside the optical fiber, up to the optical fiber inserting hole A cylindrical body that covers the ferrule for an optical connector in a state where the optical fiber element wire is inserted, and a compressed air nozzle that is connected to the cylindrical body and introduces compressed air into the inside. is there.

[0013]

As described above, according to the present invention, since the optical fiber is gradually inserted into the ferrule for optical connector by utilizing the compressed air, the diameter of the optical fiber element wire is small, and the optical fiber element for the positioning hole is small. In the situation where the ferrule can be easily inserted, such as when the axis deviation or angle deviation of the wire is small, it goes without saying that even if the ferrule is inserted quickly and vice versa, it is difficult It will be inserted relatively slowly but surely without applying excessive force. Further, it is possible to rotate or vibrate the ferrule by generating a vortex depending on how compressed air is flown, and it is possible to further improve the effect of inserting the ferrule.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of an optical connector ferrule inserting apparatus 1 of the present invention. As shown in the figure, this ferrule insertion device for optical connector 1 has a base 2
And an optical fiber fixing base 3 erected on the base 2,
The guide rail mounting base 5 is provided upright at the other end of the base 2 and has a guide rail 4 mounted along its length, and is vertically positioned above the optical fiber fixing base 3. Together with the tubular body 6 whose lower end is opened, one end supports the tubular body 6, and the other end is the guide rail 4 described above.
It is mainly configured by a support tool 7 that is engaged with and is movable in the vertical direction, and a compressed air nozzle 8 connected to the upper end portion of the tubular body 6.

An optical fiber holder 10 having a vertical positioning groove 9 is provided at the upper end of the optical fiber fixing base 3, and an optical fiber 12 is fitted into the positioning groove 9 as shown in the figure. As a result, the coating layer at the tip is peeled off, and the optical fiber 12 is exposed.
Is supported vertically. An optical connector ferrule 14 is fitted to the end of the optical fiber 12,
Specifically, the optical fiber element wire 13 is inserted into the optical fiber insertion hole 15 of the ferrule 14 and is in a loose fitting state.

Further, the tubular body 6 can be raised and lowered by a linear actuator (not shown) connected to a support member 7 engaged with the guide rail 4, and when descending, the ferrule for optical connector is used. It is designed to surround 14. Further, the compressed air nozzle 8 is connected to the upper end side portion of the tubular body 6 so as to be inclined in the circumferential direction, and when compressed air is blown in the tangential direction inside the tubular body 6, the compressed air nozzle 8 is compressed. It is designed to generate a vortex.

Next, the operation of this embodiment will be described.

First, the cylindrical body 6 is moved to a position sufficiently distant from the optical fiber fixing base 3, and the coating layer at the terminal portion is removed to expose the optical fiber 12 to the optical fiber 12. The optical fiber holder 10 is attached and fixed in the positioning groove 9. Next, the ferrule 14 into which the adhesive has been injected is conveyed by a manipulator (not shown) and inserted into the tip of the optical fiber wire 13 of the optical fiber 12 fixed to the optical fiber fixing base 3. The ferrule 14 is inserted by the manipulator into the optical fiber insertion hole 15 at the rear end of the ferrule 14, and not into the positioning hole 17 at the tip of the ferrule 14 described above.

Next, the cylindrical body 6 is lowered to move the ferrule 1
4 to surround the compressed air nozzle 8 in this state.
When the compressed air is delivered to the compressed air, the compressed air is blown out from the compressed air nozzle 8 in the tangential direction in the tubular body 6 and in an oblique direction, and a vortex flow of the compressed air is generated inside the tubular body 6.
As a result, the ferrule 14 is pushed down by the compressed air while rotating. Then, when the optical fiber element wire 13 projects from the tip of the ferrule 14, the delivery of the compressed air is stopped, the cylindrical body 6 is lifted and separated from the optical fiber fixing base 3, and then the optical fiber 12 is fixed. The ferrule insertion work is completed by removing it from the stand 3.

As described above, according to the present invention, the ferrule for an optical connector is inserted into the optical fiber by utilizing the compressed air. Therefore, the diameter of the optical fiber element wire is small, and the axis of the optical fiber element wire with respect to the positioning hole is small. In a situation where it is easy to insert the ferrule, such as when the deviation or angle deviation is small, it goes without saying that even if it is difficult to insert the ferrule quickly, and conversely, it is difficult to insert the ferrule into the optical fiber as in the past. It will be inserted relatively slowly but surely without applying force.

Although the ferrule was inserted into 1000 optical fibers by the device of the present invention, none of the optical fiber wires were broken inside the ferrule. Further, the tubular body is preferably formed of transparent glass or transparent resin so that the inserted state of the tubular body can be easily seen from the outside.

In the above embodiment, the compressed air nozzle 8 is provided tangentially and obliquely to the outer periphery of the tubular body 6 to generate a vortex inside the tubular body 6. As shown in FIG. 5, by providing compressed air toward the axial direction inside the tubular body 6 by providing it on the upper end of the tubular body 6 and applying vibration to the ferrule 14, the same operation as in the above embodiment,
The effect can be obtained. Further, in the above embodiment, the ferrule insertion into the optical fiber was carried out only with compressed air, but the delivery of the compressed air was stopped at the stage where the tip of the optical fiber element wire passed through the positioning hole inlet inside the ferrule, and thereafter, There is virtually no problem even if the insertion operation is performed by mechanical operation. Further, the ferrule for optical connector is not necessarily limited to the one for single core, and may be a ferrule for multi-core optical connector having a plurality of positioning holes and optical fiber insertion holes.

[0024]

In summary, according to the present invention, it is possible to prevent disconnection due to the insertion of a ferrule into an optical fiber, and it is possible to perform insertion work reliably and in a short time with a simple device. It has an excellent effect that the work efficiency of inserting the ferrule into the optical fiber is greatly improved.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of the present invention.

FIG. 2 is a side view showing another embodiment of the present invention.

FIG. 3 is a vertical cross-sectional view showing an optical fiber and an optical connector ferrule.

FIG. 4 is a longitudinal sectional view showing a state in which an optical fiber is inserted through a ferrule for an optical connector.

FIG. 5 is a side view showing an embodiment of a conventional ferrule inserting device for an optical connector.

FIG. 6 is a side view showing another embodiment of the conventional ferrule inserting device for an optical connector.

FIG. 7 is a partially enlarged view showing a state in which an optical fiber element wire is hooked at an inlet of a positioning hole of a ferrule for an optical connector.

FIG. 8 is a partial enlarged view showing a state in which an optical fiber element wire is inserted into a positioning hole inlet of a ferrule for an optical connector.

[Explanation of symbols]

 6 Cylindrical body 8 Compressed air nozzle 12 Optical fiber 13 Optical fiber element wire 14 Ferrule for optical connector 15 Optical fiber insertion hole 17 Positioning hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuya Murakami 5-1-1 Hidaka-cho, Hitachi-shi, Ibaraki Hitachi Cable Co., Ltd.

Claims (3)

[Claims] 1. An optical fiber insertion hole having a relatively large diameter is provided at a rear end while a positioning hole having a small diameter is provided at a front end for correctly positioning an optical fiber element wire exposed from the front end of the optical fiber. In the method of inserting an optical connector ferrule in which the positioning hole and the optical fiber insertion hole communicate with each other into the optical fiber, the optical fiber is inserted into the optical fiber insertion hole of the optical connector ferrule. In that state, the ferrule for the optical connector is covered with a tubular body so as to surround the ferrule, and then compressed air is flown into the tubular body from the tip direction of the ferrule for the optical connector, and the air pressure of the compressed air is applied. Inserting the optical fiber element wire located in the optical fiber insertion hole of the optical connector ferrule into the positioning hole of the optical connector ferrule. Method for inserting ferrule for optical connector, characterized by: 2. The ferrule inserting method for an optical connector according to claim 1, wherein the ferrule for the optical connector is rotated or vibrated by the flow of the compressed air. 3. An optical fiber insertion hole having a relatively large diameter is provided at the rear end while a positioning hole having a small diameter is provided at the front end for correctly positioning the optical fiber strand exposed from the end of the optical fiber. An optical connector ferrule inserting device for inserting and inserting an optical connector ferrule in which the positioning hole and the optical fiber inserting hole communicate with each other, the optical fiber up to the optical fiber inserting hole A cylindrical body that covers the ferrule for an optical connector in a state where the strands are inserted, and a compressed air nozzle that is connected to the cylindrical body and introduces compressed air into the inside thereof. Ferrule insertion device for optical connector.