JPH02281213A - Optical connector - Google Patents

Abstract

PURPOSE:To reduce splice loss and to apply an optical connector to a single mode fiber by locking a ferrule and fixing the position of the circumferential direction of the ferrule to the position where the splice loss of an optical fiber measured while the ferrule and the optical fiber are rotated around a shaft is the most excellent. CONSTITUTION:In the optical connector for connecting the optical fiber by plugging an element on a plug side where the optical fiber is provided in an element on a jack side, the element on the jack side has the ferrule 1 on the jack side, a locking part 5c which locks the ferrule 1 to a set position in a shaft direction and a holder 5 which contains them. Then, the ferrule 1 is fixed to the position where the light power value of the optical fiber 9 measured by rotating the ferrule 1 and the optical fiber 9 around the shaft is large. Thus, the splice loss is made low and the optical connector which is well attached and detached and which has excellent reproducibility where the ferrule is not rotated on the completed jack side is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a plug-in type optical connector, and particularly to an optical connector suitable for reducing connection loss.

[Conventional technology]

Conventional optical connectors include optical connectors that have the same external shape as electrical connectors and can be used together in the same external housing.

Related optical connectors of this type include, for example, Japanese Unexamined Patent Publication No. 121808/1983.

[Problem to be solved by the invention]

The above-mentioned conventional technology has a structure in which the rotation of the ferrule is not regulated, and because it is an asynchronous optical connector, there are difficulties in reproducibility and reliability when attaching and detaching, especially since it will become the mainstream of optical communication fibers in the future. No consideration has been given to applicability to single-mode fibers, and the first purpose of the grafting invention is to solve the problems of the prior art and apply it to single-mode fibers to reduce splice loss and improve reproducibility during attachment/detachment. and has sufficient strength. Our goal is to provide optical connectors.

A second object of the present invention is to absorb manufacturing variations in parts between the jack side element 1- and the plug side element,
An object of the present invention is to provide an optical connector that can further reduce connection loss and improve reproducibility during attachment and detachment.

[Means to solve the problem]

The first and second objects are such that the jack-side element has a structure including a jack-side ferrule, a locking portion that locks the ferrule at a set position in the axial direction, and a holder containing these, and This is achieved by providing a coupling means between the holder and the ferrule that fixes the ferrule so as not to rotate at a position where the optical power value of the optical fiber measured by rotating the ferrule and the optical fiber around the axis is large.

Further, the object is to include the jack-side Niremen I, the ferrule, a cylindrical alignment sleeve fitted on the outer periphery of the ferrule, a frame fitted on the ferrule and the outer periphery of the alignment sleeve, and The ferrule has a large diameter flange at approximately the middle in the axial direction, and a frame is attached to the ferrule, and a groove provided in the flange and a hood that covers the optical fiber are provided. The frame is mounted inside the holder so as to be movable in the axial direction and unrotatable in the circumferential direction via a projection provided on the inner periphery, and the frame is mounted inside the holder so as to be movable in the axial direction and in the circumferential direction. is provided with a coupling means that locks the holder in a non-rotatable manner and a locking portion that locks at a set position in the axial direction, and the coupling means between the holder and the frame rotates the frame, the ferrule, and the optical fiber together around the axis. coupling means for fixing the frame so as not to rotate at a position where the optical power value of the optical fiber measured is large; the hood is coupled to the holder via a bayonet coupling means; This is achieved by interposing a compression spring that biases the frame in a direction that brings the frame into close contact with the locking portion.

[Effect]

To assemble this optical connector and complete the element part,
First, a ferrule is wired to the optical fiber, a hood pressing spring that has been inserted into the optical fiber in advance is moved to the ferrule side, and then the ferrule is inserted and assembled by aligning the arbitrary convex portion with the groove of the holder. In this state, the plug is mated with the opposing plug or the master plug with the eccentric direction matched, and the first connection loss is measured.The combination of the convex portion of the claim and the groove of the holder is changed and the measurement is performed again. By repeating this operation at least three times, the best value can be found, and as a result, a product with low connection loss can be obtained. Furthermore, in the completed jack, an optical connector with good connection/detachment reproducibility in which the ferrule does not rotate can be easily realized.

In addition, in the frame and holder locking structure, the holder has a recess and the frame has a protrusion, so
This has the advantage that the frame, which has a small diameter and a thin wall, is reinforced by the protrusions, making the frame less likely to break.

Further, in the present invention, a coupling means is provided between the holder and the frame attached to the ferrule to fix the frame so as to be movable in the axial direction but not rotated, and the ferrule is movable in the axial direction with respect to the frame and is fixed to the frame so as not to rotate. A compression spring is interposed between the hood, which is non-rotatably engaged and connected to the jack side element via bayonet coupling means, and a large diameter flange provided on the ferrule, and this compression spring allows the frame to be connected to the jack. It is made to come into close contact with a locking part provided inside the side element. As a result, in the present invention, manufacturing variations in each member can be absorbed, and connection loss can be further reduced and reproducibility during attachment and detachment can be improved.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a front view with half of the optical connector jack element according to the present invention in cross section, FIG. 2 is a front view of the frame,
3 is a left side view of FIG. 2, and a left side view of FIG. 4.

The jack element includes a ferrule 1 to which an optical fiber 9 is attached, and an alignment sleeve 2 fitted around the outer periphery of the ferrule 1.
, a frame 4 fitted on the outside of the ferrule 1 and the alignment sleeve 2, a hood 6 covering the optical fiber 9, and a holder 5, and is used by being attached to an external housing 8.

The ferrule 1 is made of ceramic or metal, has a large diameter flange 1a formed approximately in the middle in the axial direction, and has polished end faces. The flange 1a includes:
A plurality of fitting grooves 1b are formed at regular intervals in the circumferential direction.

The alignment sleeve 2 is made of an elastic material and has a cylindrical shape, and has a vertically long slit (not shown) formed therein.

The frame 4 is formed into a cylindrical shape from metal or synthetic resin. On the outer periphery of this frame 4, as shown in FIGS. 2 and 3, first protrusions 4a are provided at equal intervals in the circumferential direction, and at the end of this embodiment, as shown in FIG. , second protrusions 4b that fit into the fitting grooves 1b formed in the flange 1a are provided at equal intervals in the circumferential direction, and the frame 4 is attached to the ferrule 1 so as to fit into the fitting grooves 1b.
b is fitted with the second protrusion 4b, so that it is movable in the axial direction and unrotatable in the circumferential direction. Furthermore, as shown in FIG. 1, the other end of the frame 4 is provided with a third ring-shaped projection 4C for preventing the alignment sleeve 2 from slipping off.

The hood 6 is formed of metal or synthetic resin into a socket shape, as shown in FIG. 1, and holds the optical fiber 9. This hood 6 is provided with two pins 6a at equal intervals in the circumferential direction for bayonet connection with a holder 5, which will be described later, and which constitutes a jack-side element B.

A compression spring 3 is interposed between the flange 1a and the hood 6. This compression spring 3 biases the frame 4 via the flange 1a in a direction to tightly contact a locking portion 5G, which will be described later, formed on the holder 5 of the jack-side double-men 1 to B, as shown in FIG. ing.

The holder 5 is made of metal or synthetic resin and is formed into a cylindrical shape capable of accommodating the frame 4 and the hood 6, as shown in FIGS. 1 and 4.

As shown in FIG. 5, the inner peripheral surface of one half of the holder 5 in the axial direction is provided with first protrusions 4a provided on the frame 4 at equal intervals in the circumferential direction. In this embodiment, six recesses 5a are formed, and after measuring the optical power value of the optical fiber 9, the recesses 5a and the first protrusion 4a fitted therein are used to determine the measured optical power value. A coupling means for fixing the optical fiber 9, ferrule 1, and frame 4 to the jack-side element B is configured at a large position. Furthermore, crank-shaped engagement grooves 5b that engage with pins 6a provided on the hood 6 are formed at one end of the holder 5 at equal intervals in the circumferential direction. The hood 6 is bayonet-coupled to the holder 5 through engagement with the holder 6a. Furthermore, as shown in FIG. 1, a locking portion 5C is provided on the inner circumferential surface of the holder 5 at an approximately intermediate portion in the axial direction.
is adapted to lock the frame 4 at a set position in the axial direction. Furthermore, fixing claws 7 are provided at the other end of the holder 5 at equal intervals in the circumferential direction, and are formed by cutting and raising a part of the holder 5 or from a separate member. The holder 5 is inserted into the outer housing 8 through the
is fixed.

The optical connector of the above embodiment is assembled and used as follows.

That is, the ferrule 1 is attached to the optical fiber 9 in advance, the hood 6 is placed over the optical fiber 9, and the ferrule 1 is attached to the optical fiber 9.
An alignment sleeve 2 is fitted to the ferrule 1, a frame 4 is mounted across the flange 1a of the ferrule 1 and the shim 2, and a compression spring 3 is interposed between the flange 1a and the hood 6.

On the other hand, the holder 5 is inserted into the outer housing 8 and fixed in advance via the fixing claws 7.

Next, the flange 1a of the ferrule 1 and the alignment sleeve 2
The frame 4 and the optical fiber 9
The hood 6 that covers the hood 6 is inserted into the holder 5. When inserting the frame 4, the first protrusion 4a provided on the outer periphery of the frame 4 is fitted into an arbitrary recess 5a formed on the outer periphery of the holder 5, and the holder 5 is inserted.
Temporarily position the frame 4, ferrule 1, and optical fiber 9 in the circumferential direction, and place the end surface of the frame 4 where the first protrusion 4a is provided against the locking portion 5C provided on the holder 5. Let them come into contact with you. On the other hand, the hood 6 pushes the pin 6a provided therein to a position where it engages with the engagement groove 5b formed in the holder 5, and the pin 6a
is engaged with the engagement groove 5b, and the hood 6 is bayonet connected to the holder 5. When the hood 6 is bayonet connected to the holder 5, the flange 1a of the ferrule 1
Due to the elastic force of the compression spring 3 interposed between the and the hood 6,
The frame 4 is pushed through the flange 1a, and the end surface of the frame 4 on the side where the first protrusion 4a is provided is crimped to the locking portions 5c formed on the holder 5. , a frame 4 is installed inside the holder 5.
The axial positions of the ferrule 1 and the optical fiber 9 are determined.

After positioning the frame 4, ferrule 1, and optical fiber 9 in the circumferential direction and axial direction with respect to the holder 5, the connection loss of the optical fiber 9 is measured. The splice loss of this optical fiber 9 can be measured using an optical power meter (not shown).
Record the splice loss displayed in , and compare it with the most preferable value determined in advance by experiment. Then, the first protrusion 4a of the frame 4 is inserted into any recess 5a of the holder 5.
The optical power value of the optical fiber 9 is measured. Furthermore, the frame 4 and hood 6 are removed from the holder 5, and the frame 4 is attached to another four parts 5a of the holder 5.
The first protrusion 4at! - At the same time as fitting the holder 5
Then, the frame 4 and the hood 6 are positioned and connected through the actions of the above-mentioned members, and the optical power value is measured again. This operation is repeated three times for each of the four parts of the holder 5 in this embodiment, and the frame 4, ferrule 1, and optical fiber 9 are fixed to the holder 5 at the position where the optical power value is the largest. do.

Therefore, according to this embodiment, by repeating the measurement of the optical power value described above three times around the axis of the ferrule 1, it is possible to connect the optical fiber 9 in the best state for connection loss. It becomes possible.

Further, in this embodiment, when inspecting the optical connector, etc., after disassembling each member at the time of attachment/detachment, the recess 5a is attached to the holder 5.
The frame 4, ferrule 1, and optical fiber 9 are fixed around the axis at a position where the optical power value is the largest through fitting with the first protrusion 4a, and the locking portion 5c is provided inside the holder 5. The frame 4, ferrule 1, and optical fiber 9 can be positioned and fixed in the axial direction through the engagement of the first protrusion 4a on the frame 4 and assembled.
It is possible to easily reproduce this when attaching and detaching.

In the present invention, the coupling means for fixing the ferrule 1 and the optical fiber 9 in the frame so as not to rotate with respect to the holder is a first protrusion 4a provided in the frame 4 and a recess 5a formed in the holder 5. 3 in the circumferential direction.
The structure is not limited to projections and recesses that fit at equally divided positions, but any structure that can measure optical power values at a plurality of positions may be used.

〔Effect of the invention〕

As explained above, according to the present invention, the ferrule is locked at a set position in the axial direction by the locking part provided inside the jack side element, and the optical fiber is measured while rotating the ferrule around the axis. Since the position of the ferrule in the circumferential direction is fixed by the coupling means provided between the jack side element and the ferrule at the position where the connection loss is the best, the connection loss can be reduced.
It is applicable to single mode fibers and has the effect of reproducing good usage conditions when connecting and disconnecting plugs and jacks.

Furthermore, according to the second aspect of the present invention, a coupling means is provided between the holder and the frame attached to the ferrule to fix the frame so as to be movable in the axial direction but not to rotate, and the holder is attached with a bayonet. A compression spring is interposed between the hood connected via the coupling means and the large diameter flange provided on the ferrule, and this compression spring causes the frame to engage the locking part provided inside the jack side element. Since they are brought into close contact with each other, variations in manufacturing of each member in the axial direction are absorbed, which has the effect of further reducing connection loss and improving reproducibility during attachment and detachment.

[Brief explanation of drawings]

Fig. 1 is a front view with half of the optical connector according to the present invention in cross section, Fig. 2 is a front view of the frame, Fig. 3 is a left side view of Fig. 2, and Fig. 4 is a half of the holder. FIG. 5 is a front view in section, and FIG. 5 is a left side view of FIG. 4. 1... Ferrule, 1a... Flange, 1
b... Fitting groove, 2... Alignment sleeve, 3
...Compression spring, 4...Frame, 4 a
, 4 b, 4 c - 1st. Second. third protrusion,
5...Holder, 5a...Recess, 5b...
- Engagement groove, 5c...Locking portion, 15...16, 6...Hood, 7...Fixing claw, 9...Optical fiber. 6a...Pin, 8...External housing, 5th country 5α--Pin S...Small Rude γ--To optical fiber"

Claims (1)

[Claims] 1. In an optical connector in which a plug-side element having a plug-side ferrule with an optical fiber attached thereto is inserted and coupled into a jack-side element, the jack-side element is connected to the jack-side ferrule, and this ferrule is attached as an axis. The light of the optical fiber is measured by rotating the ferrule and the optical fiber around an axis between the holder and the ferrule. An optical connector characterized in that a coupling means is provided to fix the ferrule so that it does not rotate at a position where the power value is large. 2. The jack-side element includes the jack-side ferrule, a cylindrical alignment sleeve fitted around the outer periphery of the jack-side ferrule, a frame fitted around the ferrule and the outer periphery of the alignment sleeve, a holder containing these, and a light. a hood that covers the fiber; a large-diameter flange is provided approximately in the middle in the axial direction of the ferrule; a frame is provided on the ferrule; and a fitting groove is formed on either the flange or the frame. and a protrusion provided on the other side, the holder is mounted movably in the axial direction and non-rotatably in the circumferential direction, and is disposed inside the holder to lock the frame at a set position in the axial direction. A concave portion for holding the stop portion movably in the axial direction and non-rotatably in the circumferential direction is provided, and a protrusion that engages with the concave portion of the holder is provided on the outer periphery of the frame, so that the frame is held between the holder and the frame. and a coupling means for fixing the frame to the holder so as not to rotate at a position where the optical power value of the optical fiber measured by rotating the ferrule and the optical fiber together around the axis is large, and bayonet coupling means for the hood to the holder. 2. The optical connector according to claim 1, further comprising a compression spring interposed between the flange and the hood to bias the frame in a direction that brings the frame into close contact with the locking portion.