JP2002196189A - Optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical connector that can cope with termination connectable to connectors of a plurality of single-core coated optical fibers or the like, having a comparatively large diameter, by efficiently absorbing difference in array pitch between an optical fiber on an optical connector ferrule side and an optical fiber which is intended to be terminated. SOLUTION: The optical connector is equipped with a pitch-changing part 64, which changes pitch of several optical fibers, between a tip end wall 52j, with optical fibers fixed in the optical connector ferrule 52 and an aligning mechanism 59b of connecting mechanism.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical connector, and more particularly, to an optical connector ferrule-side optical fiber which can be connected to a connector by a connection mechanism provided at a rear end of the optical connector ferrule. The present invention relates to an optical connector for connecting an optical fiber.

[0002]

2. Description of the Related Art As an optical connector which can be easily connected simply by pushing it into an optical connector adapter, for example, FIG.
An optical connector 1 as shown in (a) and (b) is provided. The optical connector 1 is a so-called MTRJ type optical connector, and has a mechanism similar to an MPO type optical connector (Multifiber Push On) defined in JIS C5982, that is, a tensile strength member exposed to an optical cord 2 terminal. A caulking member for retaining (Kevlar) and an optical cord 2
An optical connector ferrule 3 for terminating an optical fiber (mainly an optical fiber core) drawn out from a terminal so as to be butt-connectable, and a biasing means (a coil spring or the like) for biasing the optical connector ferrule 3 forward in the butt-connection direction. ) Are provided inside the housing 5. When the optical connectors 1 are inserted from both sides of the optical connector adapter 6, the optical connector ferrules 3 of the optical connectors 1 abut each other, and the optical fibers internally fixed to the optical connector ferrules 3 are optically connected to each other. The optical connector ferrule 3 is a so-called M defined in JIS C5981.
Since a T-type optical connector (MT: Mechanically Transferable) is employed, a guide pin hole 3b formed on both sides of the joint end face 3a of the optical connector ferrule 3 on one optical connector 1 side is inserted into the other optical connector ferrule. By inserting a guide pin (not shown) protruding from the optical connector 3, the optical connector ferrules 3 are precisely positioned, and one or a plurality of optical connectors 1 are exposed at the joint end face 3 a of the optical connector ferrule 3. Optical fiber 2a (bare fiber;
8 (a) and 8 (b) are precisely positioned and butt-connected. In the optical connector 1 inserted into the optical connector adapter 6, the engaging claw 7b at the tip of the latch 7 protruding forward from the housing 5 in the direction of insertion into the optical connector adapter 6 has an engaging hole of the optical connector adapter 6. By being removably engaged with 8, the pull-out is restricted. As a result, the urging force of the urging means housed in the housing 5 of each optical connector 1 acts on the butting force between the butted optical connector ferrules 3 and the optical fiber 2
The desired low connection loss is realized between a (between the optical fibers 2). Latch 7 exposed outside optical connector adapter 6
When the lever 7a is pushed in to release the latch 7 from the engagement hole 7 of the optical connector adapter 6 to release the engagement, the optical connector 1 can be pulled out from the optical connector adapter 6. The flexible boot 9 attached to the rear end of the housing 5 (the rear end in the insertion direction into the optical connector adapter 6) prevents the optical cord 2 from being sharply bent so as to affect the optical characteristics. .

Meanwhile, there is a demand for an optical connector that can be easily assembled at the end of an optical fiber in the field. In view of this, recently, as shown in FIGS. There has been proposed an optical connector having a configuration in which an optical connector main body 23 in which a connection mechanism 27 is assembled on the rear end side (the side facing the joining end face 22a) is housed in a housing 5. The optical connector body 2
3 is a portion of the optical fiber 21 incorporated in the optical connector ferrule 22 inserted into the connection mechanism 27;
Optical fiber 26 inserted from its rear end into connection mechanism 27
Are butt-connected in the connection mechanism 27 so that the optical fiber 26 can be connected to a connector via the optical fiber 21 built in the optical connector ferrule 22 (hereinafter sometimes referred to as “connector termination”). ). The optical connector main body 23 is attached to the front side (left side in FIG. 9) of the optical connector in the connection direction of the optical connector by a biasing member 38 (spring here) built in the housing 5 as a rear end side of the optical connector main body 23. Although it is urged, it is prevented from coming off by a stopper (not shown) provided inside the front end of the housing 5 in the connection direction.

The optical connector ferrule 22 conforms to JIS C
MT type optical connector (MT: Mech
FIG. 10
As shown in FIG. 2, a plurality of optical fibers 21 (bare fiber.
In FIG. 10, two are built-in, and the polished joint end face 22a
, The tip of each optical fiber 21 is exposed and can be butt-connected. The positioning between the optical connector ferrules 22 to be connected is determined by the guide pins 22d inserted between the optical connector ferrules 22 in the same manner as the MT type optical connector. The portion of the optical fiber 21 protruding toward the rear end of the optical connector ferrule 22 is inserted into the connection mechanism 27, and the rear end of the connection mechanism 27 (separated from the optical connector ferrule 22). Butt-connected to another optical fiber 26 inserted from the rear end side of the optical fiber 26). The optical fiber 26 is a multi-core optical fiber tape, an optical cord, or the like (two-core optical fiber tape in FIGS. 9 and 10), and the optical fiber 26a having its distal end removed and exposed. Further, the bare fiber exposed by removing the coating at the tip is exposed to an aligning mechanism (here, an aligning groove 29) provided in an element portion 28 having a split structure constituting a connecting mechanism 27.
V-groove, U-groove, round groove, etc. (V grooves in FIGS. 11A and 11B)
Then, by inserting from the rear end side of the connection mechanism 27, the alignment of the optical connector ferrule 2 is adjusted with high accuracy.
The optical fibers 21 on the two sides are butt-connected.
9 and 10, the window 22f is filled with an adhesive or a refractive index matching material or the like into a fine hole 22g (see FIG. 9) for holding and positioning and holding the optical fiber 21 in the optical connector ferrule 22. It is for.

[0005] As shown in FIGS. 9 and 10, the element section 28 of the connection mechanism 27 is provided with the optical connector ferrule 2.
Rod-shaped element 2 fixed in a protruding state from the rear end side of element 2
An optical fiber 21 is connected between the optical fiber 21a and the two elements 28b and 28c connected in the longitudinal direction on the element 28a.
The connection mechanism 27 holds the optical fibers 21, 26a inserted between the element 28a and the elements 28b, 28c into the optical fibers 21, 26a.
8c-shaped sleeve-shaped spring 3 mounted on the outside of 8c
0 (see FIGS. 11 (a) and 11 (b)) so as to be clamped and clamped by the clamping force. Also,
The connection mechanism 27 includes a wedge-shaped opening member 3 at a separation boundary between the element 28a and the elements 28b and 28c from the side of the element section 28.
2 (see FIG. 10) is released by press fitting.
8 is closed by pulling out the opening member 32.

The element 28a fixed to the optical connector ferrule 22 is, specifically, a portion that sandwiches the optical fibers 21 and 26a between two elements 28b and 28c provided at the rear end of the optical connector ferrule 22. The extension 28e extending from the main body is inserted into the cutout 22h formed in the optical connector ferrule 22, and is fixed to the optical connector ferrule 22 by fixing with an adhesive or the like. . On the rear end side (the side opposite to the optical connector ferrule 22) of the separation surface facing the elements 28b and 28c of the element 28a, a coating accommodation groove 31 for accommodating the coating portion 26b of the optical fiber 26 is formed. The alignment groove 29
Is formed on the separation surface of the element 28a so as to penetrate from the coating storage groove 31 to the projecting tip of the extension 28e. The alignment groove 29 and the coating storage groove 31 are:
According to the two pairs of optical fibers 21 and 26a to be connected,
Two are formed in parallel. The end of the alignment groove 29 on the extension 28e side is continuous with the fine hole 22g on the optical connector ferrule 22 side.
The optical fiber 21 on the second side is housed in the alignment groove 29 through the fine hole 22g, and is connected to the optical connector ferrule 22.
And the optical connector ferrule 22
It is drawn to a position sandwiched between the element 28b on the side.

In order to connect the target optical fiber 26 to the optical fiber 21 on the optical connector ferrule 22 side by the connection mechanism 27, the connection mechanism 2 is connected by an opening member 62.
7, the optical fiber 26 having the optical fiber 26a exposed at the distal end is removed from the rear end side of the element portion 28 of the connection mechanism 27, specifically, the rear end opening 3 of the coating storage groove 31.
It is sufficient that the optical fiber is inserted into the coating storage groove 31 from 1a, reaches the alignment groove 29, and abuts against the optical fiber 21 on the optical connector ferrule 22 side. When the element section 28 is closed while maintaining this state, the optical fibers 21 and 26a are clamped and held by the element section 28 by the clamping force of the spring 30, and the butt connection state is maintained.
The coating portion 26b of the optical fiber 26 is clamped and fixed in the coating storage groove 31 to prevent the optical fiber 26 from being pulled out. Thus, the optical connector is assembled at the tip of the optical fiber 26a, and the optical fiber 26 is terminated so as to be connectable to the connector.
In addition, the coating accommodation groove 31 is provided in the tapered alignment accuracy transition portion 3.
Since the optical fiber 26a is communicated with the alignment groove 29 via 1b, the optical fiber 26a can be smoothly inserted from the coating storage groove 31 into the alignment groove 29.

[0008]

In the above-described optical connector (optical connector having the optical connector body 23), a multi-core optical fiber such as an optical fiber 26 which is a two-core optical fiber ribbon is used. In addition to the above-mentioned connector termination, development of a connector capable of responding to the connector termination of two single-core optical fibers is expected. In particular, there has been an increasing demand for the development of an optical connector capable of terminating two single-core optical fibers having a diameter of 0.9 mm, which are easy to handle, so that they can be connected to a connector (hereinafter sometimes referred to as “connector termination”). ing.

As shown in FIG. 10 and the like, in an optical connector corresponding to a connector termination of a two-core optical fiber ribbon, for example, between the optical fibers 26a in the two-core optical fiber tape which is the optical fiber 26. Corresponding to the separation dimension (core-to-core distance t) of 0.75 mm (see FIG. 12), the entire optical fiber 21, 26a is designed so as not to be subjected to excessive bending or the like. . In the connection mechanism 27 of the optical connector described above, a guide for guiding an optical fiber single core wire 39 to the alignment groove 29 as shown in FIG. When a groove 31c is formed (constituted by a groove formed on one or both of the elements 28a and 28c) and each optical fiber single fiber can be individually guided to the alignment groove 29, two light beams are formed. It is possible to cope with the termination of the connector of the single fiber fiber. However, for example, the aforementioned 0.9 m diameter
When an optical fiber single core wire having a relatively large diameter such as m is applied, it is impossible to make the arrangement pitch of the optical fiber single core wires (the arrangement pitch of the covering portions; the center-to-center distance) smaller than 0.9 mm. For this reason, it is necessary to increase the pitch (center-to-center distance) of the guide grooves 31c to 0.9 mm or more. In this case, the difference in the arrangement pitch of the guide grooves 31c with respect to the pitch between the micro holes 22g of the optical connector ferrule 22 becomes large (the guide groove 31c is smaller than the arrangement pitch of the joint end face 22a of the optical fiber 21 on the optical connector ferrule 22 side) The arrangement pitch of the optical fiber 31c is much larger), and there is no concrete configuration for absorbing a large pitch difference which occurs when the single optical fiber 39 having a diameter of about 0.9 mm is applied. Therefore, even if the guide groove 31c is used instead of the coating storage groove 31, it is practically impossible to terminate a plurality of optical fiber single-core wires having a relatively large diameter such as a diameter of 0.9 mm. Therefore, there is a need for a specific and appropriate technique capable of efficiently absorbing a pitch difference with a simple configuration and realizing a connector termination of an optical fiber single core wire having a relatively large diameter such as 0.9 mm. Was.

[0010] Further, the optical connector main body as described above (a connection mechanism for aligning and connecting the optical fiber of the optical connector ferrule side and the target optical fiber to the rear end side of the optical connector ferrule by a centering mechanism is provided. The optical connector to which the present invention is applied is not limited to the MTRJ type optical connector, and various configurations such as an MPO (Multifiber Push On) type optical connector can be adopted. It is common to various optical connectors to which the connector body can be applied.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has a connection mechanism for butt-connecting a plurality of target optical fibers terminated to be connectable to a connector and a plurality of optical fibers on an optical connector ferrule side. In the optical connector comprising, it is possible to efficiently absorb the difference in the arrangement pitch between the optical fiber on the optical connector ferrule side and the intended optical fiber to be terminated, and to cope with a termination that can be connected to a plurality of optical fibers by a connector, In particular, an object of the present invention is to provide an optical connector that can handle a connector-connectable termination of a plurality of optical fibers having a relatively large diameter such as a diameter of 0.9 mm.

[0012]

According to the first aspect of the present invention, there is provided an optical connector for holding a plurality of optical fibers positioned side by side so that they can be butt-connected by being inserted into a tip wall having a joint end face for butt-connection. A ferrule, a centering mechanism for aligning another optical fiber with respect to the plurality of optical fibers provided on the rear end side of the optical connector ferrule facing the joining end face and protruding toward the rear end side of the optical connector ferrule; An optical connector comprising: a connection mechanism for positioning, aligning, and butt-connecting the optical fibers, wherein the alignment mechanism sets the another optical fiber from a horizontal arrangement pitch of the plurality of optical fibers on the joint end face of the optical connector ferrule. Are also arranged side by side at a wide array pitch to align the positioning. Between the tip wall and the centering mechanism of the connection mechanism, a plurality of optical fibers on the optical connector ferrule side are bent or inclined and drawn through, so that the arrangement pitch between the optical fibers side by side is reduced. A pitch converter for conversion is provided. Claim 2
According to a preferred embodiment of the present invention, in the optical connector according to the first aspect, the pitch converter is provided with a length of 6.7 mm or more between the tip wall and the alignment mechanism. And

In this optical connector, by inserting an optical fiber into the connection mechanism and connecting the optical fiber to the optical fiber on the optical connector ferrule side, the optical connector ferrule can easily terminate the target optical fiber so that the connector can be connected. It is possible to easily assemble the optical connector at the end of the target optical fiber. In the connection mechanism, an optical fiber (optical fiber on the optical connector ferrule side) pulled in from the optical connector ferrule via a pitch conversion unit provided between the tip wall of the optical connector ferrule and the element unit of the connection mechanism is used. The centering mechanism aligns the position so that the butt connection is possible. The pitch converter is a region between the tip wall of the optical connector ferrule and the element portion of the connection mechanism through which the optical fiber of the optical connector ferrule is bent or inclined and is drawn. When the pitch between the alignment axes of the mechanism and the arrangement pitch of the optical fibers in the end wall of the optical connector ferrule are different from each other, the plurality of optical fibers on the optical connector ferrule side are curved or inclined to the pitch conversion unit. By adjusting the pitch between the optical fibers to the pitch between the alignment axes, the optical fiber can be pulled into the alignment mechanism of the connection mechanism without difficulty. In the invention according to claim 2, the pitch between the centering axes of the centering mechanism is ensured by securing a length of 6.7 mm or more in the extending direction in the pitch conversion part extending from the distal end wall to the centering mechanism. The difference between the pitch of the optical fibers on the tip wall of the optical connector ferrule and the pitch of the optical fibers (side by side) can be efficiently absorbed without adversely affecting the optical characteristics of the optical fibers on the optical connector ferrule side. . In the description, the “array pitch” may be abbreviated as “pitch” in some cases. The same applies to the following.

For example, in a case where a plurality of single-core optical fibers having a relatively large diameter such as a diameter of 0.9 mm are terminated so as to be connectable to a connector, as described in "Problems to be Solved by the Invention", Generally, the horizontal arrangement pitch of the optical fibers in the connection mechanism is larger than the horizontal arrangement pitch of the optical fibers on the optical connector ferrule side, but it is longer than 6.7 mm in the extending direction. By adjusting the arrangement pitch between the plurality of optical fibers on the optical connector ferrule side by the pitch conversion section that ensures the pitch, the pitch between the alignment axes of the alignment mechanism that positions the target optical fiber to be terminated. Can be adapted to

In a configuration in which the pitch conversion unit provided between the tip wall of the optical connector ferrule and the element unit of the connection mechanism converts the arrangement pitch between the optical fibers on the optical connector ferrule side, the pitch conversion unit extends If the length in the direction is too short,
When the optical fiber on the optical connector ferrule side is deformed such as a curve for pitch conversion, the optical characteristics are adversely affected (increase in loss, etc.). Therefore, as a result of diligent studies, the present inventor has found a configuration that secures a length of 6.7 mm or more in the extending direction of the pitch conversion section in the case of two cores, which is the minimum number of cores to be applied. If the pitch converter has a length of 6.7 mm or more in the extending direction, for example, in accordance with the design of a general MT type optical connector, a small pitch in a small area of the tip wall of the optical connector ferrule is used. The optical fibers arranged side by side at high density are arranged with a size of 0.9 mm or more, which is the minimum arrangement pitch of optical fibers of 0.9 mm in diameter, due to deformation such as bending at the pitch conversion part. Even if the pitch is converted, there is no effect on the optical characteristics and no inconvenience such as an increase in loss occurs. Further, the optical connector of the present invention is not limited to two-core optical connectors, but is also applicable to connector terminations of three or more optical fibers. When applied to an optical fiber having three or more cores, if the arrangement pitch of the optical fibers on the optical connector ferrule side is to be changed (enlarged) by deformation such as bending in the pitch conversion section, generally the ends (one end or both ends) are arranged side by side. Although the amount of deformation of the located optical fiber tends to increase, by increasing the length of the pitch converter in the extending direction (to a length exceeding 6.7 mm),
The arrangement pitch can be converted without adversely affecting the optical characteristics of the optical fiber.

The third aspect of the present invention is the first or second aspect.
The optical connector according to claim 1, wherein the connection mechanism includes the alignment mechanism between elements constituting an element part having a split structure that sandwiches the optical fiber on the optical connector ferrule side and the another optical fiber, and an optical connector ferrule. The other optical fiber and the other optical fiber are configured to be clamped and held on the element portion by a clamping force of a spring, and on one element constituting the element portion, the one optical element is projected from the one element. The optical fiber housing groove, into which the optical fiber on the optical connector ferrule side is freely drawn and wired within the groove width, is inserted from the centering mechanism over the extended portion fixed to the cut portion of the optical connector ferrule. The pitch conversion unit is formed so as to be continuous with a position where the optical fiber is fixed on the distal end wall of the optical connector ferrule. Characterized in that by the optical fiber storage groove on an extension portion which is a region for converting the arrangement pitch between the optical fibers of the optical connector ferrule side. According to this optical connector, the overall size of the optical connector can be reduced due to the configuration in which the extension part forming the pitch conversion unit is housed in the optical connector ferrule.

According to a fourth aspect of the present invention, in the optical connector according to the third aspect, the extension portion is inserted into a space provided inside the optical connector ferrule, and is opened at a side portion of the optical connector ferrule. The optical fiber on the optical connector ferrule side is bonded and fixed to the optical fiber storage groove by an adhesive filled in the optical fiber storage groove on the extension portion in the space through the opened window. It is characterized by the following. According to this optical connector, the optical fiber housing groove of the extension inserted into the space inside the optical connector ferrule can be visually confirmed from the outside through the window opened on the side of the optical connector ferrule.
The optical fiber can be efficiently bonded and fixed to the optical fiber storage groove on the extension in the space inside the optical connector ferrule.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical connector 50 according to an embodiment of the present invention will be described below with reference to the drawings. The optical connector 50 employs an optical connector main body denoted by reference numeral 53 instead of the optical connector main body 23 of the optical connector illustrated in FIGS. 9 to 11, and includes the housing 5 and the urging member 38 (coil spring). Employs the same one as the optical connector illustrated in FIGS. In the figure, the same parts as those in FIGS. 9 to 11 are denoted by the same reference numerals, and the description is simplified.

FIG. 1 shows an optical connector body 5 of the optical connector 50.
3 is a perspective view showing the optical fiber main body 53, and FIG. 3 is a connection mechanism 5 of the optical connector main body 53.
7 is a plan view showing an element 58a (an element fixed to the optical connector ferrule 52), FIG. 4 is a cross-sectional view taken along the line BB of FIG. 1, (a) is an open state, and (b) is This shows a clamp state.

As shown in FIGS. 1-4 (a) and (b),
The optical connector 50 has a configuration in which an optical connector main body 53 in which a connection mechanism 57 is assembled on the rear end side of the optical connector ferrule 52 (the side facing the joint end face 52a) is housed in the housing 5. The optical connector main body 53 includes an optical fiber 5 built in the optical connector ferrule 52.
The optical fiber 56 is optically connected to the optical connector ferrule by butt-connecting the portion inserted into the connection mechanism 57 and the optical fiber 56 inserted into the connection mechanism 57 from the rear end side. The connector 52 can be connected to a connector via an optical fiber 51 incorporated therein. The optical connector main body 53 is biased by a biasing member 38 (here, a coil spring) built in the housing 5 as a rear end side of the optical connector main body 53.
It is urged forward in the connection direction of the optical connector (left side in FIG. 9). However, since the optical connector main body 53 is prevented from falling off by a stopper (not shown) provided inside the front end of the housing 5 in the connection direction, it does not come off from the front end of the housing 5. The optical connector body 53 also functions independently as the optical connector according to the present invention.

The optical connector ferrule 52 conforms to JIS C
MT type optical connector (MT: Mech
3, a plurality of optical fibers 51 (bare fiber; two in FIG. 2) are built in, and a polished joint end face 52a is provided with a tip of each optical fiber 51 as shown in FIG. Are exposed and can be connected by butt connection. The guide pin 52d (see FIGS. 1 and 2) is a guide pin for the MT type optical connector defined in JIS C5981.
When the optical connector ferrule 5 is inserted into the optical connector ferrule 52, it functions as a pin for positioning between the optical connector ferrules 52 at the time of butt connection.
In 2, it is adhesively fixed. The optical connector ferrule 52 has a space 52c therein, and the joint end face 52a
Is formed on the outer surface side of the tip wall 52j on the tip side in the connection direction of the optical connector ferrule 52. The optical fiber 51 on the optical connector ferrule 52 side is connected to the distal end wall 52j.
And a fine hole 52 opened in the joint end face 52a
Inserted and fixed to g. The fine hole 52g corresponds to a fixing position of the optical fiber 51 on the distal end wall 52j of the optical connector ferrule 52. The optical connector ferrule is not limited to a processed MT type optical connector. For example, the arrangement pitch of a plurality of optical fibers arranged side by side on the joint end face, the arrangement pitch of the guide pins, and the like are the same as those of the MT type. It does not have to be the same as the optical connector,
By making these arrangement pitches narrower than MT-type optical connectors,
What reduced the whole size and the like can also be adopted. However, the same structure as that of the MT-type optical connector is employed for positioning the optical connector ferrules at the time of joining by using guide pins inserted over both optical connector ferrules.

Optical connector ferrule 5 of optical fiber 51
2 The part protruding to the rear end side is inserted into the connection mechanism 57, and the connection mechanism 57 uses the connection mechanism 57 from the rear end side (the rear end side separated from the optical connector ferrule 52). It is butt-connected to another optical fiber 56 to be inserted. The optical fiber 56 is a single-core optical fiber (sometimes referred to as an “optical fiber single core”), an optical cord, or the like (in this embodiment, an optical fiber single core),
The coating at the end is removed to expose the optical fiber 56a. Further, the bare fiber exposed at the end of the optical fiber 56a is connected to a centering mechanism provided in an element portion 58 having a split structure constituting the connection mechanism 57. Alignment groove 59 (V
Groove, U groove, round groove, etc. 4 (a), (b) V groove)
By inserting from the rear end side of the connection mechanism 57, the positioning and alignment are performed with high precision, and the butt connection is made to the optical fiber 51 on the optical connector ferrule 52 side.

1 and 3, an optical connector ferrule 52 is shown.
The window 52f formed in the above is for injecting an adhesive or a refractive index matching material or the like into the fine hole 52g of the optical connector ferrule 52. Further, another window 52i opened at the center of the side wall of the optical connector ferrule 52 is used to inject an adhesive into a space 52c inside the optical connector ferrule 52 or to extend an extension 58e (described later) inserted into the space 52c. )
The optical fiber 51 is used for storing and fixing the optical fiber 51 in the upper optical fiber storing groove 59a.

As shown in FIGS. 1 and 3, the connection mechanism 5
7 is provided with the optical connector ferrule 52.
Rod-like element 58 fixed in a protruding state from the rear end side
a in the longitudinal direction of the element 58a.
8a and two elements 58b and 58c which sandwich the optical fibers 51 and 56a. The connection mechanism 57 connects the optical fibers 51 and 56a inserted between the element 58a and the elements 58b and 58c to these elements 5a and 5b.
The springs 60 (see FIGS. 4 (a) and 4 (b)) having a U-shaped cross section are mounted on the outer sides of the springs 8a, 58b and 58c, and are clamped and fixed by the clamping force. Further, the connection mechanism 57 is provided from the side of the element portion 58.
The wedge-shaped opening member 62 is pressed into the separation boundary between the element 58a and the elements 58b, 58c to be opened, and the element portion 5 is opened.
8 is closed by pulling out the opening member 62.

The element 58a fixed to the optical connector ferrule 52 is, specifically, a portion where the optical fibers 51 and 56a are sandwiched between two elements 58b and 58c provided on the rear end side of the optical connector ferrule 52. And an extension 58e extending from the body and inserted and fixed in a cutout 52h formed in the optical connector ferrule 52. On the rear end side of the element portion 58,
The grooves formed on the separation surfaces of the elements 58a and 58c facing each other (FIG. 6 (b) include grooves 61c on the element 58c side).
), A plurality (two in this case) of guide grooves 61 for guiding the optical fiber 56 inserted from the rear end of the element portion 58 to the alignment groove 59 are formed side by side and in parallel. The guide groove 61 also functions as a cover storage groove for storing the cover 56b of the optical fiber 56. A plurality of (two in this case) alignment grooves 59 formed on the separation surface of the element 58a are formed in parallel with each other in correspondence with the plurality of guide grooves 61.

As shown in FIG. 6B, the element 58b provided on the optical connector ferrule 22 side on the element 58a
The groove 58f is formed only at the end (the right side in FIG. 6B) on the side where the element 58c is joined on the separation surface for the element 58a.
Are formed. As shown in FIGS. 1 and 5, the concave groove 58 f is provided on the optical connector ferrule 52 side with respect to the tapered alignment accuracy transition portion 61 b provided between the guide groove 61 and the alignment groove 59. A bending prevention groove and an alignment groove 59 which are provided adjacently and guide the optical fiber 56a passing from the guide groove 61 to the alignment accuracy transition portion 61b to the alignment groove 59 without giving a sharp bend. The optical fiber 56a is pressed by the pressing force applied to the optical fiber 56a which is inserted into the optical fiber 51 on the optical connector ferrule 52 side.
It functions as a curved part storage groove or the like for storing the curved part formed in a. Since the curved portion of the optical fiber 56a housed in the concave groove 58f attempts to return to the original linear shape by its own elasticity, this elastic force can function as a butting force between the optical fibers 51 and 56a. .

FIG. 5 is a perspective view showing the element 58a fixed to the optical connector ferrule 52 by the extension 58e. As shown in FIG. 5, the groove 58f of the element 58a
Alignment accuracy transition portion 61b and alignment groove 5
A communication portion with the communication groove 9 is located, and projecting walls 58h projecting from both sides of the communication portion are housed in the concave groove 58f. The optical fiber 56a guided by the guide groove 61 is inserted into the alignment groove 59 through a space between the pair of protruding walls 58h.
There is no need to worry about jumping out of the alignment accuracy transition portion 61b or the alignment groove 59.

As shown in FIGS. 3 and 5, between the optical connector ferrule 52 and the element 58a, in addition to the insertion and fixing of the extension 58e into the cutout 52h of the optical connector ferrule 52, Since the guide pin 52d protruding to the rear end side of the ferrule 52 is firmly connected to the pin fixing portion 58i of the element 58a, even if the optical connector ferrule 52 is used for a long time.
It is possible to reliably prevent the displacement such as the displacement between the cable and the connecting mechanism 57 and the deformation such as the distortion of the extension 58e.
The optical characteristics of the optical fiber 51 inserted over 7 can be stably maintained. Guide pin 52d at pin fixing portion 58i
Various configurations such as fitting, bonding with an adhesive, and the like can be adopted as the fixing method.

The alignment groove 59 is connected to the optical connector ferrule 5 through the optical fiber housing groove 59a on the extension 58e.
52 g of the second fine holes. The optical fiber 51 on the optical connector ferrule 52 side is housed in the optical fiber housing groove 59a and the alignment groove 59 from the micro hole 52g, and is sandwiched between the element 58b and the element 58a on the optical connector ferrule 52 side. Have been drawn up.

In order to terminate the optical fiber 56 by this optical connector so that the optical fiber 56 can be connected to the connector, the optical fiber 56 is attached to the distal end.
The optical fiber 56 exposing a is opened from the rear end side of the element portion 58 of the connection mechanism 57 previously opened by the opening member 62, specifically, the rear end opening 61a of the guide groove 61.
From the optical fiber 56a, the bare fiber portion at the tip of the optical fiber 56a reaches the alignment groove 59, and the optical fiber on the optical connector ferrule 52 side is precisely aligned and aligned by the alignment groove 59. Butt connection to 51 is made. Then, while maintaining this state, the release member 62 is pulled out of the element portion 58 and the element portion 58 is closed, and the optical fibers 51 and 56a are clamped and held to the element portion 58 by the clamping force of the spring 60 and butt-connected. The state is maintained. Thereby, the optical fiber 5
An optical connector is assembled at the tip of the optical fiber 56a.
Are terminated so as to be connectable to a connector. The covering portion 56b of the optical fiber 56 is accommodated in the guide groove 61, and is also clamped and fixed to the element portion 58 by the clamping force of the spring 60, thereby preventing the optical fiber 56 from being pulled out. Since the guide groove 61 has lower alignment accuracy than the alignment groove 59, the insertion of the optical fiber 56a from the rear end opening 61a into the guide groove 61 is easy.
In addition, the guide groove 61 is provided with a tapered alignment shift portion 61.
b, the guide groove 6 communicates with the alignment groove 59.
The insertion of the optical fiber 56a from 1 into the alignment groove 59 is performed smoothly.

As shown in FIG. 2, the spring 60 comprises two pairs of leaf spring portions 60b, 60b separated through a slit 60a.
c is the element portion 5 corresponding to the elements 58b and 58c, respectively.
Since it functions independently as a spring for clamping of 8, the clamp fixing of the optical fibers 51 and 56a and the clamp fixing of the covering portion 56b of the optical fiber 56 are reliably performed with appropriate clamping forces. On the other hand, the opening member 62 also includes a plurality of insertion projections 62a, 62b individually inserted into a plurality of recesses 63a, 63b formed on the separation boundary corresponding to the elements 58b, 58c on the side surface of the element portion 58. Since there,
It is easy to adjust the amount of opening of each part of the element unit 58 by the opening member 62.

As shown in FIG. 4A, the elements 58a,
In a state where the release member 62 is press-fitted into the separation boundaries 8b and 58c to open the element portion 58 against the clamping force of the spring 60, the optical fiber 56a can be freely inserted into or pulled out of the alignment groove 59. , As shown in FIG.
When the release member 62 is pulled out from the element portion 58, the element portion 58 is closed by the clamping force of the spring 60, and the element 58 is closed.
The optical fiber 56a is clamped and fixed between a and 58b,
Moreover, the optical fibers 51 and 56a are pressed toward the bottom of the alignment groove 58, and are positioned and aligned with high precision. From this clamped state, if the release member 62 is again pressed into the separation boundary of the element portion 58 to be in the release state, the connection mechanism 57
From the optical fiber 56a. Thus, the replacement of the optical connector 50 with the optical fiber 56 can be performed efficiently.

As shown in FIG. 3, in the optical connector 50, the horizontal pitch of the guide grooves 61 of the connection mechanism 27 is smaller than the horizontal pitch of the joint end face 52a of the optical fiber 51 on the optical connector ferrule 52 side. Is larger. The optical fiber receiving groove 59a connects the optical fiber 51 on the optical connector ferrule 52 side to the connection mechanism 5.
Optical fiber 56 within optical fiber 7 (optical fiber 56a in detail)
Performs the function of guiding to a butt connection position with respect to The aligning groove 59 functions as an aligning mechanism as a whole. In particular, the optical fibers 51 and 56a
The portion where is pressed functions as an alignment mechanism for positioning and aligning the optical fibers 51 and 56 so that they can be butt-connected (hereinafter, “alignment mechanism 59b”).

As shown in FIG. 1, FIG. 3, and FIG. 5, the optical fiber housing groove 59a is a pitch conversion section 6 which is an area secured between the distal end wall 52j and the alignment mechanism 59b.
4, two optical fibers 51 on the optical connector ferrule 52 side and two alignment mechanisms 59b on the connection mechanism 57 side.
, Two are formed side by side. In addition, each optical fiber housing groove 59a is provided with the alignment groove 59 of the alignment mechanism 59b.
The optical fiber 51 can be freely drawn through and wired (for example, a curved wiring) depending on the range of the groove width. For this reason, for example, two optical fibers 51
Can be converted (in this case, expanded) in such a way that the horizontal arrangement pitch is gradually expanded from the front end wall 52j side to the alignment mechanism 59b side. The pitch between the optical fibers 51 can be freely changed within the range of the groove width of the optical fiber housing groove 59 a and can be drawn into the connection mechanism 57.

In other words, the pitch converter 64 is configured such that the plurality of optical fibers 51 on the optical connector ferrule 52 side are curved or inclined in the optical fiber housing groove 59a (in the present embodiment, formed on the extension 58e). When the two optical fibers 51 are drawn through the two optical fiber receiving grooves 59a (relative inclination between the two optical fibers 51), the horizontal arrangement pitch between the optical fibers 51 is changed. A sufficient length of 6.7 mm or more is ensured in the extending direction from the distal end wall 52j to the aligning mechanism 59b (the extending direction of the fine hole 52g or the direction along the aligning axis of the aligning mechanism 59b). The plurality of optical fibers 51 whose arrangement pitch has been converted by the pitch conversion unit 64 are pitch-converted without being adversely affected by optical characteristics such as an increase in loss. It is drawn into the b. Thereby, the plurality of optical fibers 51 can be positioned and aligned with respect to the intended plurality of optical fibers 56 (optical fibers 56a) to be connected to a connector at an arrangement pitch capable of butt-connecting. For example, the butt connection of the two optical fibers 51 on the optical connector ferrule 52 side to the optical fiber 56, which is a single optical fiber having a diameter of 0.9 mm, adversely affects the optical characteristics of the optical fiber 51. No, it can be easily realized.

Here, the pitch conversion section 64 is specifically formed by an extension 58e of the element 58a, and the extension of the extension 58e from the body of the element 58a has a length of 6.7 mm or more. Is secured. The extension 58e is inserted into a space 52c provided inside the optical connector ferrule 52, and is inserted and fixed in the cutout 52h. The optical fiber 51 on the optical connector ferrule 52 side is housed in the optical fiber housing groove 59a by working in the space 52c.
The optical fiber 51 is bonded and fixed to the optical fiber housing groove 59a by an adhesive 66 (see FIG. 1) filled in the optical fiber housing groove 59a. The housing of the optical fiber 51 in the optical fiber housing groove 59a and the bonding of the optical fiber 51 are performed by the window 5 opened in the optical connector ferrule 52.
2i (see FIG. 2 etc.), the optical fiber 5
1 and the optical fiber housing groove 59a can be efficiently and reliably performed while being visually observed. Further, the configuration in which the pitch conversion section 64 is accommodated in the optical connector ferrule 52 can reduce the overall size of the optical connector 50.

As shown in FIG. 5, in the pitch conversion portion 64 (extended portion 58e), on both sides of a ridge 58g extending along the longitudinal direction (the direction of projection from the main body of the element 58a),
Since the optical fiber storage grooves 59a are arranged separately,
In the work of storing the optical fiber 51 in the optical fiber storage groove 59a, the optical fiber 51 does not contact with each other, and the like.
The operation of housing and fixing the optical fiber 51 in the predetermined optical fiber housing groove 59a can be performed efficiently. Moreover, since the fixed optical fiber 51 is stored and protected in the optical connector ferrule 52, the fixed state can be stably maintained, and the optical characteristics can be stably maintained.

The optical connector according to the present invention is not limited to the MTRJ type optical connector, but is applicable to other optical connectors. FIG. 7 shows an example of application to an MPO optical connector, in which an optical connector main body 53 according to the present invention is housed in a housing 65 of the MPO optical connector.

It should be noted that the present invention is not limited to the above embodiment, and various modifications are possible. For example, the design of the optical connector according to the present invention is not limited to two cores, and the design can be changed to be applicable to a connector termination of a single core optical fiber having three or more cores.
Change the number of optical fibers on the optical connector ferrule side and the number of coating storage grooves formed in the element part of the connection mechanism according to the number of optical fibers (number of optical fibers) to be terminated. Needless to say, more than the number of fibers is required). The single-core optical fiber to be terminated by the optical connector according to the present invention is not limited to a single-core optical fiber, and may be, for example, an optical fiber cord. Further, the optical fiber applied to this optical connector is not limited to a single optical fiber,
For example, the present invention can be applied to a connector termination of a multi-core optical fiber or the like such as a multi-core optical fiber ribbon having a relatively large arrangement pitch between single-core optical fibers. The fiber can be efficiently terminated.
The alignment mechanism provided in the connection mechanism is not limited to the one using the alignment groove, and includes, for example, (1) an optical fiber inserted from both sides of a micro-capillary and butt-connected, (2) Various configurations such as one in which an optical fiber is carried between three or more precision balls or precision rods can be employed. In the connection mechanism using the alignment mechanisms (1) and (2) other than the alignment grooves, for example, on both sides of the alignment mechanism, the optical fibers to be connected are clamped and held on the element portion by a spring clamping force. Is adopted.

[0040]

As described above, according to the optical connector of the present invention, the pitch conversion portion extending from the distal end wall forming the joining end face of the optical connector ferrule to the centering mechanism is provided on the optical connector ferrule side. The arrangement pitch of the optical fibers is changed by passing a plurality of optical fibers in a curved or inclined manner. Specifically, the pitch of the optical fibers is 6.7 mm in the extending direction. By ensuring the above-mentioned length, the pitch difference between the pitch between the alignment axes of the alignment mechanism and the pitch (arrangement of the optical fibers) at the joint end face of the optical connector ferrule is determined by the optical connector ferrule side. Can be efficiently absorbed without adversely affecting the optical characteristics of the optical fiber. Thereby, for example, a single-core optical fiber having a relatively large diameter such as a diameter of 0.9 mm and having a large difference in the arrangement pitch in the side-by-side arrangement compared to the arrangement pitch in the joint end face of the optical fiber on the optical connector ferrule side. In the connection mechanism, the connection with the optical fiber on the optical connector ferrule side can be realized without difficulty, and the connector can be connected efficiently.

According to the third aspect of the present invention, since the extension forming the pitch converter for converting the pitch of the optical fiber on the optical connector ferrule side is inserted and fixed in the cutout of the optical connector ferrule, The configuration accommodated in the connector ferrule provides an excellent effect that the overall size of the optical connector can be reduced.

According to the fourth aspect of the present invention, the extension portion is inserted into a space provided inside the optical connector ferrule, and the space is opened via a window opened on a side portion of the optical connector ferrule. The optical fiber on the optical connector ferrule side is adhered and fixed to the guide groove by an adhesive filled in the guide groove on the extension portion in the optical connector. Since the guide groove of the extension inserted into the space inside the ferrule can be visually checked from the outside, the adhesive fixation of the optical fiber to the guide groove on the extension can be efficiently performed in the space inside the optical connector ferrule. It is possible to improve the efficiency of assembling work even with a miniaturized optical connector due to the structure in which the pitch conversion section is housed inside the optical connector ferrule. It exhibits the kind of excellent effect.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing an optical connector according to an embodiment of the present invention.

FIG. 2 is a perspective view showing an optical connector main body applied to the optical connector of FIG.

FIG. 3 is a plan view showing an element fixed to an optical connector ferrule among elements having a split structure constituting a connection mechanism of the optical connector main body in FIG. 2;

FIGS. 4A and 4B are cross-sectional views taken along line BB of FIG. 1, wherein FIG. 4A shows an open state, and FIG. 4B shows a clamped state.

FIG. 5 is a perspective view showing an element fixed to an optical connector ferrule by an extension.

6A and 6B are diagrams showing two elements that sandwich an optical fiber between an element constituting a connection mechanism of the optical connector main body of FIG. 2 and an element fixed to an optical connector ferrule, and FIG. FIG. 2B is a front view of the two elements, as viewed from the separation surface side.

FIG. 7 is a perspective view showing an application example of the present invention to an MPO-type optical connector.

8A and 8B are diagrams illustrating an example of a conventional optical connector, wherein FIG. 8A is an exploded perspective view, and FIG. 8B is a perspective view illustrating a state where the optical connector is inserted into an optical connector adapter.

FIG. 9 is a front sectional view showing an optical connector provided with a connection mechanism.

FIG. 10 is a perspective view showing an optical connector main body of the optical connector of FIG.

11 is a sectional view taken along the line AA of FIG. 9, and FIG.
Indicates an open state, and (b) indicates a clamped state.

FIG. 12 is a sectional view showing a multi-core optical fiber ribbon applied to the optical connector of FIG. 9;

FIG. 13 is a plan view showing a case where a guide groove for guiding a single-core optical fiber is formed in the connection mechanism of the optical connector main body of the optical connector of FIG. 9;

[Explanation of symbols]

5 housing, 50 optical connector, 51 optical fiber (optical fiber on optical connector ferrule side), 52 optical connector ferrule, 52a joining end face, 52c space
52g: Fixing position (micro hole) of optical fiber on tip wall of optical connector ferrule, 52h: Cut, 52i ...
Window 52j tip wall 56 optical fiber (single optical fiber) 56a optical fiber 57 connection mechanism 58
Element part, 58a, 58b, 58c: Element, 58e: Extension part, 59: Alignment groove (alignment mechanism), 59a: Optical fiber housing groove, 59b: Alignment mechanism, 60: Spring, 64: Pitch conversion part, 65 ... housing.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yasuhiro Tamaki 1440, Musaki, Sakura-shi, Chiba F-term in Fujikura Sakura Works (reference) 2H036 JA01 QA02 QA22 QA50

Claims (4)

[Claims] 1. A joint end face for butt connection (52a)
An optical connector ferrule (52) for holding a plurality of optical fibers (51) positioned side by side so as to be inserted into the end wall (52j) formed with the connector so as to be butt-connected, and faces the joint end face of the optical connector ferrule. A plurality of optical fibers (56, 56a) provided on the rear end side and protruding to the rear end side of the optical connector ferrule are positioned and aligned with another optical fiber (56, 56a) by a centering mechanism (59, 59b). Connection mechanism for butt connection (57)
Wherein the centering mechanism arranges the other optical fibers side by side at a wider arrangement pitch than the arrangement pitch of the plurality of optical fibers at the joint end face of the optical connector ferrule. Between the distal end wall of the optical connector ferrule and the alignment mechanism of the connection mechanism, a plurality of optical fibers on the optical connector ferrule side are curved or inclined. An optical connector (50), comprising a pitch conversion unit (64) for converting a horizontal arrangement pitch between the optical fibers by being drawn. 2. The optical connector according to claim 1, wherein the pitch converter is provided with a length of 6.7 mm or more between the tip wall and the alignment mechanism. . 3. The element (58a, 5a, 5a, 5b) that constitutes an element portion (58) having a split structure that sandwiches the optical fiber on the optical connector ferrule side and the another optical fiber.
8b, 58c) and the centering mechanism is provided.
The optical fiber on the optical connector ferrule side and the another optical fiber are configured to be clamped and held on the element unit by a clamping force of a spring (60). Notch (5) protruding from the element of
2h) over the extension (58e) inserted and fixed, the optical fiber on the optical connector ferrule side is freely drawn through and wired within the range of the groove width.
9a) a fixing position (52) of the optical fiber on the distal end wall of the optical connector ferrule from the centering mechanism;
g), wherein the pitch conversion portion is a region for changing the arrangement pitch between the optical fibers on the optical connector ferrule side by the optical fiber housing groove on the extension portion. The optical connector according to claim 1. 4. A window (52i) in which the extension is inserted into a space (52c) provided inside the optical connector ferrule, and is opened on a side portion of the optical connector ferrule.
The optical fiber on the optical connector ferrule side is bonded and fixed to the optical fiber storage groove by an adhesive filled in the optical fiber storage groove on the extension portion in the space through the optical fiber storage groove. The optical connector according to claim 3, wherein: