JPH08122569A - Optical connector - Google Patents

Abstract

PURPOSE: To provide an optical connector which is easily aligned and is extracted/inserted by a small force. CONSTITUTION: A ferrule 1 having an optical fiber has the figure 8-shaped section like two partially overlapped circles, and a fixed block 6 having a V groove which is brought into contact with one circular arc part of the ferrule 1 and a mobile block 7 having a V groove which is brought into contact with the other circular arc part are provided in parallel in an adapter 2 to which the ferrule 1 is inserted, and a pressing member 8 which faces the V groove sides of both blocks 6 and 7 with the ferrule 1 between them and presses the ferrule 1 to these V grooves is provided in the adapter 2, and the mobile block 7 is moved sideways to the inserting direction of the ferrule 1 by this pressing force.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connector for connecting an optical fiber to an optical element or the like, and more particularly to an optical connector which is easy to position and has a small insertion / removal force.

[0002]

2. Description of the Related Art A receptacle type connector is used for detachably connecting an optical fiber to an optical element or the like fixed to a module.

As shown in FIG. 9, the receptacle type connector is a detachable connector, in which a plug (ferrule) 91 is inserted into a receptacle (adapter) 92 for use. The ferrule 91 has an end portion of the optical fiber 93, and the adapter 92 is attached to the module so that the ferrule 91 can be inserted and removed reproducibly. Within the adapter, as shown in FIG. 10, a structure 94 is required such that the ferrule 91 is fixed in the same position each time it is inserted.

When a cylindrical ferrule is used, FIG.
As shown in FIG. 1 (a) and FIG. 11 (b), a V-groove block 11 in which a V-shaped groove (V-groove) 111 is dug in an adapter.
2 is provided, and the ferrule 113 is placed in this V groove 111,
There is a method in which the ferrule 113 is pressed against the V-groove block 112 from above to perform alignment.

[0005]

[Problems to be Solved by the Invention]
As shown in (b), when the ferrule 123 has a cross-sectional shape of a figure 8 in which two circles are connected, in order to apply the above method, the V-groove block 122 has two rows in contact with each circular arc portion. The V-shaped groove 121 is required.

However, the cylindrical ferrule 113 has a V
The 8-shaped ferrule 123 comes into contact with the V-shaped groove 121 at four points, while it comes into contact with the groove 111 at two points. More specifically, as shown in FIG. 5, the alignment cannot be achieved unless the ferrule 51 and the V groove 52 are in contact with each other at the four points 53, 54, 55, 56 as seen from the cross section. However, it is difficult to align them so that all four points touch. This is because the ferrule has a slight difference in width (outer diameter). It is also difficult to process the ferrule 51 and the V groove 52 so that all four points are in contact with each other.

However, if all four points come into contact with each other, the force for pressing the ferrule from above is dispersed, the pulling-out force becomes small, and it becomes easy to attach and detach.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the above problems and provide an optical connector which is easy to align and has a small insertion / removal force.

[0009]

In order to achieve the above object, the present invention is directed to a ferrule having an optical fiber having an eight-shaped cross section in which two circles are connected, and the ferrule is inserted into an adapter. And a movable block having a V groove in contact with one circular arc portion of the ferrule and a movable block having a V groove in contact with the other circular arc portion are arranged side by side, and face each other to the V groove sides of both blocks via the ferrule in this adapter. A pressing member for pressing the ferrule against these V grooves is provided, and the pressing force causes the movable block to move laterally with respect to the inserting direction of the ferrule.

Means for limiting the moving range of the movable block may be provided in the adapter.

Further, there are two ferrules having an optical fiber.
It has an 8-shaped cross section in which two circles are connected, and the cross section of the adapter into which the ferrule is inserted has two parallel sides that are in contact with both sides of the ferrule in the major axis direction, and the positions on these two sides that oppose each other. A cross-sectional shape having two hypotenuses extending in directions closer to each other is provided, and a pressing member that faces the inner angles of both hypotenuses via ferrules and presses the ferrules against these hypotenuses is provided in this adapter.

[0012]

According to the present invention, as shown in FIG. 6, the two V-grooves 61 and 62 are fixed blocks 63 and movable blocks 64.
It will be provided separately. Movable block 6
4 is movable laterally with respect to the inserting direction, that is, in a direction perpendicular to the axis of the ferrule. This causes the movable block 64 to move in accordance with the outer shape of the ferrule when inserting the ferrule.

As shown in FIG. 7, the movable block 64 is in an unspecified position before the ferrule is inserted.

As shown in FIG. 8, when the ferrule 81 is inserted, the ferrule 81 is pushed by the pressing member.
It is pressed against the two V grooves 61 and 62. Ferrule 81
When the position of the V groove is not aligned with that of the fixed block 6,
The ferrule 81 is displaced with respect to 3 and is aligned with the V groove 61. With respect to the movable block 64, a force acts on the side of the V groove 62 that is in contact with the ferrule 81, and no force acts on the side that is not in contact with the ferrule 81. Therefore, according to this force, the movable block 64 is inserted in the insertion direction. With respect to the ferrule 81, the ferrule 81 is aligned with the V groove 62. In this way, the ferrule contacts the respective V-grooves at the above-mentioned four points, and the alignment is achieved.

The movable block 6 before inserting the ferrule
Even if 4 is in an unspecified position, the V groove 62 should not come off from the arc portion of the ferrule. By providing a means for limiting the moving range of the movable block 64 in the adapter, the movable block does not move more than necessary.

Further, the cross-sectional shape of the adapter into which the ferrule is inserted has two parallel sides which are in contact with both sides in the major axis direction of the ferrule, and two oblique sides extending in directions approaching each other from the positions facing each other on these two sides. When the cross-sectional shape is held, the ferrule is pressed against these hypotenuses by the pressing member. The ferrule is aligned by contacting two parallel sides and two hypotenuses at four points.

[0017]

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

As shown in FIG. 1, the main part of the optical connector comprises a ferrule 1 and an adapter 2. 1a is
It is a plug housing part. The ferrule (8-shaped ferrule) 1 having the ends of the plurality of optical fibers 3 has a cross-sectional shape that is formed by joining two circles, that is, a 8-shaped shape. The tip of the ferrule 1 is tapered. On the other hand, an adapter 2 is provided between the optical element array fixed to the module and the ferrule 1 so as to have reproducibility of insertion and removal.

As shown in FIG. 2, the optical element array 4 has an effective light receiving surface in the shape of a figure eight.
A guide plate 5 having a countersink-shaped through hole whose cross-sectional shape is a figure of 8 and whose diameter is narrowed according to the depth is provided on the insertion side of the adapter 2 attached to the. A substantially rectangular hollow portion surrounded by an inner wall is provided in the adapter 2, and a fixed block 6, a movable block 7, and a pressing member 8 are provided in the hollow portion.

As shown in FIG. 3, a fixed block 6 having a V groove and a movable block 7 having a V groove are provided side by side on the lower side of the hollow portion in the adapter 2, and a pressing member 8 is provided on the upper side. ing. The V groove of the fixed block 6 is symmetrical in inclination, and the oblique side on the movable block 7 side is short. The V-groove of the movable block 7 is symmetrical in inclination, and the oblique side on the fixed block 6 side is short. The fixed block 6 and the movable block 7 have equal heights on their side surfaces facing each other,
When the two are put together, it becomes a block having exactly two rows of V-grooves, and when they are separated, it becomes like a division into two in the mountain portion between the V-grooves. The fixed block 6 is fixed to the adapter 2 at a position in contact with the inner wall on one side, and the movable block 7 is not fixed. The sum of the lateral width of the fixed block 6 and the lateral width of the movable block 7 is smaller than the lateral width of the hollow portion. Movable block 7
Can be moved laterally.

On the lower side of the movable block 7, a laterally projecting protrusion 9 is provided. The inner wall of the adapter 2 is provided with a groove 10 into which the protrusion 9 is fitted. The projecting portion 9 and the groove 10 are means for limiting the moving range of the movable block 7, and restrict unnecessary movement of the movable block 7. For example, if the movable block 7 is largely separated from the fixed block 6 when the ferrule 1 is not inserted, it is inconvenient that the arc portion of the ferrule is located outside the V groove when the ferrule 1 is inserted.
The movable block 7 is restricted from being largely separated from the fixed block 6. Further, if the movable block 7 is completely free to move in the direction of the pressing member 8, the movable block 7 may overturn or overlap the fixed block 6 when the ferrule 1 is not inserted, and the ferrule 1 is inserted. At this time, the desired alignment operation cannot be obtained, so that the movable block 7 is engaged by the engagement of the protrusion 9 and the groove 10.
The movement of the pressing member in the direction of 8 is restricted.

The width of the upper side of the hollow portion is widened on both sides, and the holding plate 11 and the leaf spring 12 constituting the pressing member 8 are accommodated in the wide portion. The leaf spring 12 contacts the upper portion of the inner wall of the adapter 2 on both sides of the wide portion, and bulges downward at the central portion. The holding plate 11 is in contact with the bulge of the plate spring 12. When the ferrule 1 is inserted downward, the holding plate 11 serves to push the ferrule 1 downward by the bias of the leaf spring 12.

Next, the operation of the embodiment will be described.

When inserting the ferrule 1 into the adapter 2, first the tip of the ferrule 1 is guided by the guide plate 5,
It is inserted between the fixed block 6 and the movable block 7 and the pressing member 8. By the guide of the guide plate 5, the tip end of the ferrule 1 almost comes to the position of the V groove of the fixed block 6 in the outer peripheral portion corresponding to one arc portion. At this time, the movable block 7 is in an indefinite position within the range allowed by the means for limiting the moving range.

When the ferrule 1 is inserted, the movable block 7 is moved by the outer peripheral portion corresponding to the other circular arc portion at the tip of the ferrule 1. As a result, each V groove comes to a position where it is almost in contact with the ferrule 1 at the four points described in FIG. Then, the ferrule 1 stops at an appropriate position according to the difference in the minute width (outer diameter) of the ferrule 1.

Another embodiment of the present invention will be described.

FIG. 4 shows an embodiment of the optical connector which does not use the V groove block. Different from the example of FIG. 3 except that the pressing member 8 is the same, the inner wall of the hollow part of the adapter 2 contacts the ferrule 1. Therefore, the width of the hollow portion is substantially equal to the major axis of the ferrule 1. Then, the side edges 42 contacting both sides of the ferrule 1 in the major axis direction are parallel to each other,
Oblique sides 43, 43 are formed at the corners of the lower side 41 and the side sides 42, 42. The oblique sides 43, 43 extend so as to be closer to each other than the positions on the side edges 42, 42 opposed to each other and inclined at the same angle. The pressing member 8 is the hypotenuse 4
It will face the inner corner of 3,43.

In this case, when the ferrule 1 is inserted, the ferrule 1 is pushed by the pressing member 8 and comes into contact with the side edge 42 and the oblique edge 43 at four points for alignment. This structure does not use the V-groove block and therefore has an advantage of being inexpensive.

[0029]

The present invention exhibits the following excellent effects.

(1) Since the V groove is designed to move laterally,
A positional relationship in which four points contact each other can be obtained simply by inserting a ferrule, which facilitates positioning.

(2) Since all four points are in contact with each other, the force for pressing the ferrule from above is dispersed, the insertion / removal force becomes small, and the attachment / detachment becomes easy.

[Brief description of drawings]

FIG. 1 is a perspective view of an optical connector showing an embodiment of the present invention.

FIG. 2 is an exploded perspective view of an adapter of the optical connector of FIG.

FIG. 3 is a cross-sectional view showing a state where the optical connector of FIG. 1 is inserted.

FIG. 4 is a sectional view showing a state in which an optical connector according to another embodiment of the present invention is inserted.

FIG. 5 is a cross-sectional view showing how the ferrule and the V groove are in contact with each other.

FIG. 6 is a sectional view of a fixed block and a movable block of the present invention.

FIG. 7 is a sectional view of the adapter before inserting the ferrule of the present invention.

FIG. 8 is a sectional view of the adapter when the ferrule of the present invention is inserted.

FIG. 9 is a perspective view of a receptacle-type connector.

FIG. 10 is a perspective view of the receptacle-type connector as viewed from inside the adapter.

FIG. 11 is a cross-sectional view and a perspective view showing a method of aligning a cylindrical ferrule.

12A and 12B are a cross-sectional view and a perspective view showing a method of aligning the figure-8 ferrule.

[Explanation of symbols]

 1 Ferrule 2 Adapter 6 Fixed block 7 Movable block 8 Pressing member

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuo Teraoka 5-1-1 Hidaka-cho, Hitachi-shi, Ibaraki Hitachi Cable Company, Ltd., Optro System Laboratories (72) Inventor Takeshi Kato 1-chome, Higashikoigakubo, Kokubunji, Tokyo No. 280, Central Research Laboratory, Hitachi, Ltd.

Claims (3)

[Claims] 1. A fixing block in which a ferrule having an optical fiber has a sectional shape of a figure 8 in which two circles are connected, and a V groove which is in contact with one arc portion of the ferrule is provided in an adapter into which the ferrule is inserted. And a movable block having a V groove in contact with the other circular arc portion are provided side by side,
A pressing member that faces the V groove sides of both blocks via the ferrule and presses the ferrule against these V grooves is provided in this adapter, and the pressing force causes the movable block to move laterally with respect to the inserting direction of the ferrule. Optical connector characterized by 2. The optical connector according to claim 1, wherein means for limiting a moving range of the movable block is provided in the adapter. 3. A ferrule having an optical fiber has a cross-sectional shape of a figure 8 in which two circles are connected, and the cross-sectional shape of an adapter into which the ferrule is inserted has a parallel shape that is in contact with both sides in the major axis direction of the ferrule. It has a cross section with two sides, which have sides and extend in a direction closer to each other than the positions facing each other on these two sides, and the ferrule is pressed into these adapters by facing the inner angles of both sides via ferrules in this adapter. An optical connector comprising a pressing member.