JP2002148477A - Optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the damage and the oscillation of an optical fiber cable. SOLUTION: The front end surface of core of an optical fiber cable 2 and a front end surface of covering are positioned in one plane. The optical fiber cable 2 is enveloped by a double-split ferrule 3 split, and the optical fiber cable 2 and the ferrule 3 are fixed by two fixtures 4. The front end surface of the optical fiber cable 2 and front end surface 3b of the ferrule 3 are positioned in one plane in a housing 1 so as not to project from the front end surface 1a of the housing 1. The peripheral wall 6a of the intermediate housing chamber 6 of the housing 1 has an inside diameter to closely contact the peripheral surface 3e of the ferrule 3, and the distance in the axial direction of the peripheral wall 6a is elongated a little than the distance between the projections 16 of the ferrule 3 and a flange 12. One groove 6b which passes the base part 21 of the fixture 4 forward and two grooves which pass the projections 16 of the ferrule 3 forward and do not pass the flange 12 are formed on the peripheral wall 6a of the intermediate housing chamber 6 of the housing 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connector having a ferrule attached to the tip of an optical fiber cable housed in a housing.

[0002]

2. Description of the Related Art In a conventional optical connector of this type, a core at an end of an optical fiber cable is stripped from a coating and projected from a front end surface of a housing, and a ferrule is locked to the housing by a flexible arm.

[0003]

However, since the core at the end of the optical fiber cable is stripped from the coating and projected from the front end surface of the housing, the core of the optical fiber cable is easily damaged. Further, since the ferrule is locked to the housing by the flexible arm, there is a problem that the optical fiber cable is easily swung.

An object of the present invention is to solve the above-mentioned problems,
An object of the present invention is to provide an optical connector that can prevent damage and swing of an optical fiber cable.

[0005]

An optical connector according to the present invention for achieving the above object has a ferrule attached to an outer peripheral surface of an optical fiber cable having a coating around a core, and the ferrule accommodated from a rear end surface side. An optical connector comprising a housing and a front end face of the core of the optical fiber cable and a front end face of the coating are formed on the same plane, and the ferrule is fixed in the housing.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail based on the illustrated embodiment. FIG. 1 is a front view of the embodiment, and FIG.
FIG. 2 is a partial cross-sectional view of the housing 1 of FIG. 1 taken along the line A-A. The optical fiber cable 2 is wrapped by a ferrule 3 divided into two, and the optical fiber cable 2 and the ferrule 3 are, for example, two fixtures. 4 fixed. In the housing 1, for example, the ends of two optical fiber cables 2 are accommodated and fixed via ferrules 3, and in FIG. Part is ferrule 3
Is housed through.

The housing 1 is made of a synthetic resin and has a front end face 1a and a rear end face 1b. The front end surface 1a side of the housing 1 is a front accommodation room 5 for accommodating the front part of the ferrule 3, and the middle between the front end surface 1a and the rear end surface 1b of the housing 1 is an intermediate accommodation room 6 for accommodating an intermediate part of the ferrule 3. The rear end face 1b side of the housing 1 is a rear accommodation chamber 7 for accommodating the rear part of the ferrule 3. A mating housing (not shown) is fitted into the front housing chamber 5 of the housing 1, and the ferrule 3 is fixed so as not to swing in the intermediate housing chamber 6.

FIG. 3 is an assembled perspective view of the optical fiber cable 2 and the ferrule 3, FIG. 4 is a side view, FIG.
FIG. 6 is a cross-sectional view taken along the line BB of FIG. 4. The optical fiber cable 2 includes a core 2a made of an optical fiber and a coating 2b for protecting the core 2a. Is cut and polished so that the front end face of the core 2a and the front end face of the coating 2b are located in the same plane.

The ferrule 3 is formed in two pieces from a synthetic resin material and has a contact surface 3a, a front end surface 3b, a rear end surface 3c, an inner peripheral surface 3d and an outer peripheral surface 3e. The inner diameter of the circle formed by the inner peripheral surfaces 3 d of the two ferrules 3 is smaller than the outer diameter of the optical fiber cable 2, and the ferrule 3 can be pressed against the optical fiber cable 2. On the outer peripheral surface 3e of the ferrule 3, a small diameter portion 11 is provided on the front end surface 3b side, and a flange 12 is formed near the rear end surface 3c.

A pair of left and right slots 13 communicating between the inside and outside of the ferrule 3 are formed in two rows at the rear of the small diameter portion 11 and the rear of the flange 12 of the ferrule 3. The portion of the ferrule 3 sandwiched between the left and right slots 13 is the fixing device 4
Of the ferrule 3 and a second locked portion 15 which is locked by the other part of the fixing tool 4. I have. A pair of left and right projections 16 is formed at the rear of the second row of slots 13 from the front end face 3b of the ferrule 3 so as to be engaged with a peripheral wall of the housing 1 to be described later. Is provided with a guide surface 16a.

As shown in the perspective view of FIG. 7, the fixture 4 has a substantially U-shape and has a base 21 having a concave longitudinal section for engaging with the first locked portion 14 of the ferrule 3. I have. Base 21
From the four corners, four arm portions 22 respectively entering the adjacent slots 13 of the ferrule 3 are raised substantially at right angles. At the tip of the arm 22, a protrusion 23 that engages with the second locked portion 15 of the other ferrule 3,
A blade portion 24 for cutting the coating 2b of the optical fiber cable 2 so as not to reach the core 2a is formed. At least the blade portion 24 of the protrusion 23 and the blade portion 24 is provided so as not to protrude from the outer peripheral surface 3 e of the other ferrule 3. And the ferrule 3 has its front end face 3b
The optical fiber cable 2 is fixed to the optical fiber cable 2 by a fixture 4 so that the front end face of the optical fiber cable 2 is located in the same plane.

The peripheral wall 6a of the intermediate storage chamber 6 of the housing 1 has an inner diameter which is in close contact with the outer peripheral surface 3e of the ferrule 3, and the axial distance of the peripheral wall 6a is equal to the protrusion 1 of the ferrule 3.
It is slightly longer than the distance between 6 and the flange 12. One groove 6b is formed in the peripheral wall 6a of the intermediate storage chamber 6 of the housing 1 to allow the base 21 of the fixture 4 to pass forward, and the protrusion 16 of the ferrule 3 is caused to pass forward but the flange 12 passes. Two grooves 6c that are not to be formed are formed. The ferrule 3 is fixed to the peripheral wall 6a of the housing 1 so that the front end face of the optical fiber cable 2, that is, the front end face 3b of the ferrule 3 does not project from the front end face 1a of the housing 1.

When the ferrule 3 is attached to the optical fiber cable 2, the front end faces 3 b of both ferrules 3 are aligned with the front end face of the optical fiber cable 2, and both ferrules 3 are connected to the outer peripheral surface of the optical fiber cable 2. , And the arm 22 of the fixture 4 is pushed into the slot 13 of the one ferrule 3. As a result, the protrusion 23 of the fixture 4 is pressed against the outer side wall of the slot 13 of the ferrule 3, the arm 22 is bent inward, and the blade 24 advances while cutting the coating 2 b of the optical fiber cable 2. .

At the same time that the base 21 of the fixture 4 comes into contact with the first locked portion 14 of the one ferrule 3, the projection 23 of the fixture 4 is moved to the slot 1 of the other ferrule 3.
3, the arm 22 of the fixture 4 is restored, and the protrusion 23 is engaged with the second locked portion 15 of the other ferrule 3. As a result, the fixture 4 is connected to the optical fiber cable 2.
The two ferrules 3 are fixed to the optical fiber cable 2 with the front end face of the ferrule 3 and the front end face 3b of the ferrule 3 aligned.

Next, when the ferrule 3 attached to the optical fiber cable 2 is housed in the housing 1, the fixture 4 of the ferrule 3 and the projection 16 are inserted from the rear end face 1 b of the housing 1 into the grooves 6 b and 6 c of the housing 1. , And the ferrule 3 is pushed into the housing 1. As a result, the front fixture 4 and the projection 16 of the ferrule 3 appear in the front storage chamber 5 of the housing 1, and the flange 12 of the ferrule 3 comes into contact with the rear surface of the peripheral wall 6 a of the housing 1. At this time, the inner peripheral surface of the peripheral wall 6a of the housing 1 is in close contact with the outer peripheral surface 3e of the ferrule 3 to prevent rattling in a direction orthogonal to the axis of the ferrule 3. And
When the ferrule 3 is rotated while being pressed sufficiently, the projection 16 and the flange 12 of the ferrule 3 slide on the front and rear surfaces of the peripheral wall 6a, respectively, and the front and rear surfaces of the peripheral wall 6a of the housing 1 are brought into contact with the projection 16 and the flange 12 of the ferrule 3. The ferrule 3 is pressed to prevent the ferrule 3 from rattling in the axial direction.

As described above, in the embodiment, the front end face of the core 2a of the optical fiber cable 2 and the front end face of the coating 2b are formed in the same plane, so that the side face of the core 2a can be exposed as in the conventional case. In addition, damage to the optical fiber cable 2 can be prevented.

If the front end faces 3b of the two ferrules 3 and the front end face of the optical fiber cable 2 are located in the same plane and are not projected from the front end face 1a of the housing 1, damage to the optical fiber cable 2 can be obtained. Can be more favorably prevented. The inner peripheral surface of the peripheral wall 6a of the housing 1 prevents rattling in the direction perpendicular to the axis of the ferrule 3, and the front and rear surfaces of the peripheral wall 6a of the housing 1 rattle in the axial direction of the ferrule 3. , The swing of the ferrule 3 can be reliably prevented.

In the above-described embodiment, the description has been given of the case where the ferrule 3 is attached to the optical fiber cable 2. It goes without saying that a similar effect can be achieved.

FIG. 8 shows another embodiment, in which elastic rubber 30 or the like is attached to the inside of the tip of the ferrule 3 so that the tip of the optical fiber cable 2 maintains a stable posture. . Alternatively, a gap may be provided between the optical fiber cable 2 and the ferrule 3, and a rubber ring or the like may be fitted therein.

[0020]

As described above, in the optical connector according to the present invention, since the front end face of the core of the optical fiber cable and the front end face of the coating are formed in the same plane, the side face of the core is not exposed. Thus, damage to the optical fiber cable can be prevented.

A first projection and a second projection are provided on the outer peripheral surface of the ferrule at an interval in the axial direction, and the first projection of the ferrule is allowed to pass through the housing and the second projection is provided. If a peripheral wall is provided between the first projection and the second projection that has a groove that makes the portion impermeable,
The swing of the optical fiber cable can be prevented.

[Brief description of the drawings]

FIG. 1 is a front view of an embodiment.

FIG. 2 is a partial cross-sectional view of the housing of FIG. 1 taken along line AA.

FIG. 3 is an assembled perspective view of an optical fiber cable and a ferrule.

FIG. 4 is a side view.

FIG. 5 is an exploded vertical sectional view.

FIG. 6 is a sectional view taken along line BB of FIG. 4;

FIG. 7 is a perspective view of a fixture.

FIG. 8 is a cross-sectional view of another embodiment.

[Explanation of symbols]

 Reference Signs List 1 housing 1a front end surface 1b rear end surface 2 optical fiber cable 2a core 2b coating 3 ferrule 3a contact surface 3b front end surface 3c rear end surface 3d inner peripheral surface 3e outer peripheral surface 4 fixture 6 intermediate storage chamber 6a peripheral wall 6b, 6c groove 12 flange 16 protrusions

Claims (6)

[Claims] 1. An optical connector comprising: a ferrule attached to an outer peripheral surface of an optical fiber cable having a coating around a core; and a housing accommodating the ferrule from a rear end surface side. The front end face and the front end face of the coating are formed as the same plane,
An optical connector, wherein the ferrule is fixed in the housing. 2. A front end face of the optical fiber cable and a front end face of the ferrule are located in the same plane.
An optical connector according to claim 1. 3. The optical connector according to claim 1, wherein the ferrule has a split structure. 4. The optical connector according to claim 1, wherein the split ferrule is fixed by a fixture. 5. A first projection and a second projection are provided on an outer peripheral surface of the ferrule at intervals in an axial direction, and the first projection of the ferrule is allowed to pass through the housing. The optical connector according to claim 1, further comprising a peripheral wall having a groove that prevents passage of the second protrusion and being in close contact between the first protrusion and the second protrusion. 6. The axial distance between the peripheral wall of the housing and the first protrusion of the ferrule is equal to the distance of the second protrusion.
6. The optical connector according to claim 5, wherein the distance between the protrusions is slightly larger than the distance between the protrusions.