JP2002267886A - Optical connector - Google Patents

Abstract

(57) [Summary] [Problem] It is preferable to connect an optical connector optical fiber and a mating optical fiber or a mating optical component, which can reduce shock when connecting optical connectors and realize stable connection characteristics. To provide an optical connector that can be used for the optical connector. SOLUTION: The optical connector according to the present invention has a ferrule 2 having at least one optical fiber positioning hole 2a and a pair of guide holes 2c, a locking claw 3a for fitting, and a groove 3b for retaining the locking claw 3a. And a housing 3 for housing the ferrule 2 therein. When the housings 3 are fitted to each other, the end face 2 of the ferrule 2 is provided.
b. The locking claws 3a and the housing 3 are brought into contact with each other earlier than the timing of contact between them, and the reaction force after the locking claws 3a are elastically deformed reduces the impact force between the end faces 2b of the ferrule 2. It is characterized by.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connector used for connecting an optical fiber to another optical fiber or an optical component.

[0002]

2. Description of the Related Art On an optical transmission line, it is necessary to connect optical fibers to each other or to connect optical fibers to optical components. Although there are various connection methods, it is common practice to connect the ends of the optical fibers into connectors. Examples of such an optical connector include U.S. Pat. No. 6,116,790 and JP-T-2000-515986.
And the like described in Japanese Patent Application Laid-Open Publication No. H10-163, etc. are known. The optical connectors described in these publications include a ferrule for holding an end of an optical fiber and positioning the optical fiber with a mating optical fiber (optical component), and housing the ferrule therein to fit with the mating optical connector. And a housing provided with a mechanism for performing the above.

[0003] By fitting the optical connectors together, the connection end faces of the ferrules are brought into contact with each other to form a so-called P connector.
Connect to C (Physical Contact). The fitting of the optical connectors is performed by locking the locking projections (claws) and the locking recesses (grooves) formed on the housing. Further, the positioning of the ferrules is performed by a pair of guide pins and guide holes.

[0004]

However, when the above-mentioned optical connector is repeatedly attached and detached, the impact of the contact between the end faces at the time of fitting is repeatedly applied, so that the end face of the optical fiber is scratched to improve the connectivity. It is feared that it will worsen.
The ferrule is generally a resin molded product, but is often filled with a glass filler to improve dimensional stability. Due to the repeated impact of the contact between the end faces at the time of fitting, the glass filler falls off and enters between the end faces of the optical fiber, damaging the optical fiber or forming a gap, thereby preventing the PC connection from being performed normally. It is also feared.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an optical connector which can reduce the shock at the time of connection between optical connectors and realize stable connection characteristics.

[0006] In a connector such as an SC connector or an MU connector, the ferrules are positioned by using a member called a split sleeve. Since a structure in which friction occurs between the split sleeve and the ferrule is employed, if the optical connector is positioned using a member such as the split sleeve, there is no concern about the damage due to the collision between the connection end faces described above. The present invention relates to an optical connector that does not have such a split sleeve, and to an optical connector that positions a ferrule with each other using a guide hole.

[0007]

According to a first aspect of the present invention, there is provided an optical connector including a ferrule having at least one optical fiber positioning hole and a pair of guide holes, a locking claw for fitting, and a locking claw. An optical connector having a housing having a groove for retaining and housing a ferrule therein, wherein when the housings are fitted to each other, the locking claws and the housing are first moved in comparison with the timing at which the ferrule end faces come into contact with each other. The method is characterized in that the impact force between the ferrule end faces is reduced by the reaction force after the locking claw is elastically deformed by contact.

[0008] The optical connector according to the second aspect is the first aspect.
In the invention described in the above, the material of the housing is PBT resin, and the contact position between the locking claw and the housing is
Move the contact position between the ferrule end faces backward by 0.2 to 2.0.
It is characterized by having a configuration arranged with a shift amount of mm.

The optical connector according to the third aspect is the second aspect.
In the invention described in the above, the above-mentioned shift amount is set to 0.4 to
It is characterized by 1.5 mm. This defines a particularly preferable range among the ranges described in claim 2.

An optical connector according to a fourth aspect is the optical connector according to the first aspect.
In the invention described in the above, the material of the housing is PPS resin, and the contact position between the locking claw and the housing is
Move the contact position between the ferrule end faces backward by 0.2 to 2.0.
It is characterized by having a configuration arranged with a shift amount of mm.

The optical connector according to the fifth aspect is the fourth aspect of the present invention.
In the invention described in the above, the above-mentioned shift amount is set to 0.4 to
It is characterized by 1.5 mm. This defines a particularly preferable range among the ranges described in claim 4.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the optical connector according to the present invention will be described with reference to the drawings. 1 shows the upper surface of the optical connector, FIG. 2 shows the side surface, FIG. 3 shows the lower surface, and FIG. 4 shows the connection end surface. 5 is a sectional view taken along line BB in FIG. 2, FIG. 6 is a sectional view taken along line CC in FIG. 2, and FIG. 7 is a sectional view taken along line AA in FIG. However, the optical connector shown in FIGS. 1 to 4 is a type that does not have a guide pin described later. On the other hand, the optical connector shown in FIGS. 5 to 7 is a type having a guide pin. The only difference between the two is the presence or absence of a guide pin.

The optical connector of the present embodiment is an optical fiber 1
And a housing 3 housing the ferrule 2 therein and having a fitting mechanism. The ferrule 2 is a commonly used MT ferrule. Inside the ferrule 2, an optical fiber positioning hole 2a for accommodating and positioning the distal end of the tape-shaped optical fiber 1 is formed (see FIG. 4). The end face of the distal end of the optical fiber 1 housed in the optical fiber positioning hole 2 a is exposed at the connection end face 2 b of the ferrule 2.

The ferrule 2 is formed with a pair of guide holes 2c parallel to the optical fiber 1 so as to be located on both sides of the optical fiber 1. Each guide hole 2c is formed to penetrate from the connection end surface 2b to the opposite end surface (referred to as a rear end surface 2d). A pink lamp 4 is pressed by a spring 5 on the rear end face 2 d of the ferrule 2. In the case of the optical connector having the guide pin 6, the pink lamp 4 clamps (clamps) the base end of the guide pin 6. In the case of the optical connector having no guide pin 6, the pink lamp 4 is simply the rear end face 2d of the ferrule 2.
(A hole for attaching the base end of the guide pin 6 may or may not be formed).

A pair of guide pins 6 whose base ends are held by the pink lamp 4 are inserted into the above-described guide holes 2c,
The tip protrudes from the connection end face 2b. The ferrule 2 is housed in a housing 3 which is a cylindrical body having a substantially square cross section. The housing 3 has a stepped portion inside, and the stepped portion narrows the internal space on the distal end side of the housing 3. The flange of the ferrule 2 abuts on the stepped portion so that the ferrule 2 pressed by the spring 5 does not protrude from the housing 3.

A sub-housing 7 is fitted on the base end side of the housing 3 to form a reaction force surface on the base end side of the spring 5. The sub-housing 7 has a hole formed in the center thereof, and the above-described optical fiber 1 is inserted into this hole. A further easily deformable boot 8 made of rubber is attached to the base end of the sub housing 7. Boots 8
The optical fiber 1 is also inserted. Boots 8
Prevents the optical fiber 1 from being sharply bent at the base end side of the optical connector.

On the front end side of the housing 3, a pair of locking claws (locking claws) 3a and a pair of locking recesses (grooves for locking the locking claws) 3b are formed. For convenience of explanation, the upper surface of the optical connector shown in FIG. 2 will be described as an upper surface, and the lower surface will be described as a lower surface. Further, the front end side of the optical connector is defined as the front side, and the base end side is defined as the rear side. The locking claw 3a is formed on the upper surface side of the optical connector with the claws facing each other. The locking claw 3a has a claw at the tip of a cantilevered arm, and this arm can be elastically deformed. This locking claw 3
a is formed so as to slightly protrude outside the housing 3 main body. On the other hand, the pair of locking recesses 3b is formed on the lower surface side of the optical connector so as to be adjacent to each locking claw 3a. Each locking recess 3 b is formed on the outer surface of the housing 3.

As described above, the locking claw 3a and the locking recess 3
Since the b is formed, the optical connector having the guide pin 6 and the optical connector having no guide pin 6 can be fitted upside down. At this time,
One of the locking claws 3a is locked by the other locking recess 3b, and the other locking claw 3a is locked by the one locking recess 3b to maintain the fitted state.

Further, the positioning of the optical connectors in the vertical direction at the time of fitting is performed by a positioning plane 3c formed on the side wall surface of the housing 3. The positioning plane 3c is formed on a side wall surface perpendicular to the arrangement plane of the pair of guide holes 2c, and the extending direction of the plane is parallel to the guide holes 2c. When the optical connectors are fitted to each other, the positioning planes 3c are brought into contact with each other, so that the optical connectors are roughly positioned in the vertical direction. The accurate positioning of the ferrules 2 is performed by the above-described guide holes 2c and the guide pins 6.

Incidentally, a cylindrical adapter (not shown) may be used to facilitate the fitting between the optical connectors. Such an adapter is configured to house the optical connector therein, is attached to the outside of one optical connector in advance, and performs approximate positioning with the other optical connector therein. When the other optical connector is inserted into the adapter attached to one of the optical connectors, the positions of the guide pins 6 and the guide holes 2c substantially match, and the other optical connectors are pushed in as they are, so that the other optical connectors are pushed in. Are fitted.

FIGS. 8 to 1 show the connection process between the optical connectors.
3 is shown. One (left side in the figure) optical connector does not have the guide pin 6. The other (right side in the figure) optical connector has a guide pin 6. The pair of optical connectors are configured using exactly the same members except for the presence or absence of the guide pins 6. As can be seen from the figure, upon connection, the pair of optical connectors are arranged such that the upper and lower surfaces are upside down. In this state, when the two members are moved forward with respect to each other, first, the tips of the pair of guide pins 6 are inserted into the guide holes 2c of the optical connector (FIG. 9).

When the optical connectors are further advanced with respect to each other, the locking claw 3a comes into contact with the wall near the locking recess 3b (FIG. 10). Elastic deformation of the periphery of 3b starts (FIG. 11).
The peripheral portion of the locking recess 3b is elastically deformed toward the inner ferrule 2 by the reaction force received from the locking claw 3a side, and the locking claw 3a is deformed outward by the reaction force received from the locking claw 3b side. And
Immediately before the locking claw 3a is locked by the locking recess 3b, the amount of elastic deformation of both becomes maximum (FIG. 12).
a and the locking recess 3b are locked (FIG. 13). When the optical connectors are locked with each other, each ferrule 2 has a spring 5
The connection end faces 2b are pressed against each other, and the connection end faces 2b are brought into close contact with each other.

Here, the optical connector of the present embodiment is formed such that the locking claw 3a and the housing 3 come into contact with each other before the connection end surfaces 2b of the ferrule 2 come into contact with each other when the optical connectors are connected. I have. That is, as can be seen from FIG. 10, when the optical connectors are connected to each other, first, the locking claw 3a and the wall portion in front of the locking recess 3b of the housing 3 abut. Then, as shown in FIG.
Are elastically deformed (although not so much as the locking claws 3a, the peripheral wall of the locking recess 3b of the housing 3 can also be deformed), and the connection end faces 2b are brought into contact with each other. By doing so, the impact force between the connection end surfaces 2b of the ferrule 2 can be reduced by the elastic restoring force of the locking claw 3a. As a result, it is possible to prevent the end face of the optical fiber 1 from being damaged by the collision at the time of contact between the connection end faces 2b.

More specifically, the housing 3 of the present embodiment is made of PBT resin.
As shown in FIG. 14, the locking recess 3 of the housing 3 (
The position Z of the connection end face 2b of the ferrule 2 is disposed rearward with a shift amount of 0.2 to 2.0 mm with respect to the contact position Y between the front wall portion b) and the locking claw 3a of the mating optical connector. (See distance α in FIG. 14). PBT housing 3
When formed of resin, by constructing such a dimensional relationship, it is possible to more effectively reduce the impact caused by the contact between the connection end faces 2b.

If the shift amount is less than 0.2 mm, the elastic restoring force (reaction force after deformation) of the locking claw 3a cannot be sufficiently utilized. On the other hand, if the above-mentioned shift amount exceeds 2.0 mm, the stroke amount after contact at the time of connection of the optical connector is large, and the optical connector becomes large in size to secure this stroke amount. There is a strong demand for optical fibers (optical connectors) to have higher densities and higher integration, and it will be difficult to achieve this.

In this embodiment, the position Z of the connection end face 2b is located rearward of the contact position Y described above. However, as shown in FIG. 15, the position Z of the connection end face 2b is located rearward (preferably within the range described above) with respect to the contact position X between the locking claw 3a and the housing 3 of the mating optical connector. (See distance β in FIG. 15). Even in this case, it is possible to reduce the impact by using the elastic restoring force of the locking claw 3a when the connection end surfaces 2b come into contact with each other.

That is, at least one of the contact position Y between the housing 3 and the locking claw 3a of the mating optical connector or the contact position X between the locking claw 3a and the housing 3 of the mating optical connector is connected. If the position Z of the end face 2b is located rearward (preferably within the range described above), the connection end face 2
At the time of contact between b, the impact can be reduced by using the elastic restoring force of the locking claw 3a. Naturally, if the position Z of the connection end face 2b is disposed rearward (preferably within the above-mentioned range) with respect to both the contact positions X and Y described above, when the connection end faces 2b come into contact with each other, the locking claw is formed. It is possible to reduce the impact by using the elastic restoring force of 3a.

Further, when the housing 3 is made of PBT resin, the above-mentioned shift amount range is particularly preferably in the range of 0.4 to 1.5 mm even within the above-mentioned range. Within this range, it is possible to achieve a high level of balance between the shock mitigation and the suppression of the increase in the size of the optical connector. Note that the contact position and the shift amount described above can be determined only by themselves because the connection partner is an optical connector having the same configuration (only the presence or absence of the guide pin 6 is different). However, the present invention may be connected to optical connectors having the same configuration (the only difference is the presence or absence of the guide pins 6). In this case, the locking mechanism should have the same form, and the same effect can be obtained.

The dimensions of the locking claw 3a are 3 mm in width and 7 m in length.
m, thickness 0.8 mm, and made of PBT resin (filled with 30% glass fiber). Locking claw 3a and housing 3
An optical connector in which the contact position between the single surfaces of the ferrules was shifted backward by 0 to 1.5 mm with respect to the contact position with the ferrule was prototyped. As a result of repeatedly performing the detachment test using the prototyped optical connector, when the shift amount is 0.5 mm or more, the fiber end face is hardly damaged, and the connection loss is 0.2 dB or less even after 500 times of repeated connection and detachment. was gotten.

In the embodiment described above, the housing 3 is
The case of forming with BT resin has been described.
It may be formed by PS resin. Also in the case where the housing 3 is formed using PPS resin, the preferable range of the above-mentioned shift amount is 0.2 to 2.0 mm, and the particularly preferable range is 0.4 to 1.5 mm. The reason is the above-mentioned PB
It is exactly the same as in the case of T resin.

The present invention is not limited to the above embodiment. For example, the form of the optical connector is not limited to the embodiment described above. An optical connector comprising a ferrule having at least one optical fiber positioning hole and a pair of guide holes, a locking claw for fitting, a housing having a groove for retaining the locking claw and accommodating the ferrule therein. If the present invention is applicable,
For example, the present invention can be applied to an optical connector described in U.S. Pat.

[0032]

According to the optical connector of the present invention, the impact caused by the contact of the end face of the ferrule is reduced by utilizing the elastic restoring force (reaction force after deformation) of the locking claw when the optical connector is connected. However, damage to the optical fiber and the ferrule can be effectively prevented.

[Brief description of the drawings]

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

FIG. 2 is a side view of the optical connector of FIG.

FIG. 3 is a bottom view of the optical connector of FIG. 1;

FIG. 4 is a front view (a front view of a connection end face) of the optical connector of FIG. 1;

FIG. 5 is a sectional view taken along line BB in FIG. 2;

FIG. 6 is a sectional view taken along line CC in FIG. 2;

FIG. 7 is a sectional view taken along line AA in FIG. 1;

8 is a cross-sectional view showing a connection process between the optical connectors of FIG.

9 is a cross-sectional view showing a process of connecting the optical connectors of FIG.

FIG. 10 is a cross-sectional view showing a process of connecting the optical connectors of FIG.

FIG. 11 is a cross-sectional view showing a process of connecting the optical connectors of FIG.

FIG. 12 is a cross-sectional view showing a connection process between the optical connectors of FIG. 1;

13 is a cross-sectional view showing a connection process between the optical connectors of FIG.

FIG. 14 is a cross-sectional view showing a positional relationship among a housing, a locking claw, and a connection end surface.

FIG. 15 is a diagram corresponding to FIG. 14 when the dimensional relationship is different from that of FIG. 14;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Optical fiber, 2 ... Ferrule, 2a ... Optical fiber positioning hole, 2b ... Connection end surface, 2c ... Guide hole, 2d ... Rear end surface, 3 ... Housing, 3a ... Locking claw (locking nail), 3
b: locking recess (groove), 3c: positioning plane, 4: pink lamper, 5: spring, 6: guide pin, 8: sub housing, 9: boot.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toshiaki Kakii 1-chome, Taya-cho, Sakae-ku, Yokohama-shi, Kanagawa F-term (reference) in Yokohama Works, Sumitomo Electric Industries, Ltd. 2H036 JA02 QA03 QA31 QA49 QA57 QA59

Claims (5)

[Claims] 1. A ferrule having at least one optical fiber positioning hole and a pair of guide holes, a locking claw for fitting, a housing having a groove for retaining the locking claw and accommodating the ferrule therein. An optical connector comprising: when the housings are fitted to each other, the locking claw and the housing are brought into contact with each other earlier than a timing at which the ferrule end faces contact each other, so that the locking claw is An optical connector characterized in that an impact force between the end faces of the ferrule is reduced by a reaction force after the elastic deformation. 2. A material of the housing is PBT resin, and a contact position between the locking claw and the housing of the mating optical connector or a contact position between the housing and the locking claw of the mating optical connector is set. 2. The optical connector according to claim 1, wherein the optical connector has a configuration in which at least one of the ferrule end faces is disposed rearward with a shift amount of 0.2 to 2.0 mm. 3. 3. The optical connector according to claim 2, wherein the shift amount is set to 0.4 to 1.5 mm. 4. A contact position between the locking claw and the housing of the mating optical connector, or a contact position between the housing and the locking claw of the mating optical connector, wherein the material of the housing is PPS resin. 2. The optical connector according to claim 1, wherein at least one of the ferrules has a configuration in which the ferrule end face is arranged rearward with a shift amount of 0.2 to 2.0 mm. 3. 5. The optical connector according to claim 4, wherein the shift amount is 0.4 to 1.5 mm.