JP7526637B2 - Optical connector and method for manufacturing the same - Google Patents

Description

The present invention relates to an optical connector and a method for manufacturing an optical connector.

Patent Document 1 discloses an optical connector that includes a ferrule, a spring that biases the ferrule, and a housing that accommodates the ferrule. When assembling such an optical connector, a member that holds the ferrule is generally inserted into the housing from the rear.

JP 2007-121599 A

When assembling optical connectors, the member that holds the ferrule is inserted from the rear of the housing, which can make assembly difficult.

The present invention was made in consideration of these circumstances, and aims to provide an optical connector or a method for manufacturing an optical connector that can improve the ease of assembly.

In order to solve the above problem, an optical connector according to one aspect of the present invention includes a ferrule body having a fiber hole and a connection end face in which the fiber hole opens, and when the connection end face side of the fiber hole in the axial direction is the front and the opposite side is the rear, the optical connector has a ferrule unit that holds a first optical fiber that is inserted into the fiber hole and extends rearward from the ferrule body so that it can be connected to another optical fiber, a first insertion port into which the ferrule unit can be inserted from the front, and a second insertion port into which the other optical fiber can be inserted from the rear, a housing that accommodates at least a part of the ferrule unit inside, and a spring that is accommodated inside the housing and biases the ferrule unit forward within the housing, and when the direction that intersects the center axis of the fiber hole as viewed from the axial direction is the radial direction, the ferrule unit has a flange portion that is the outermost part of the ferrule unit in the radial direction, and the housing has a locking piece that is elastically deformable in the radial direction, and the locking piece has an abutment portion that abuts against the flange portion from the front.

According to the above aspect, the abutment portion of the housing abuts against the flange portion from the front, preventing the ferrule unit biased by the spring from falling out of the housing forward. When manufacturing the optical connector, the ferrule unit can be inserted into the housing from the front, elastically deforming the locking piece and causing the abutment portion to abut against the flange portion from the front. This allows the ferrule unit to be biased forward by the spring and to be movable backward within the housing. This improves the workability when assembling the optical connector.

Here, the flange portion may contact the spring and the abutment portion.

The housing may also have a third insertion opening through which the spring can be inserted into the housing from the outside in the radial direction.

The flange portion may also have a notch formed therein, and the abutment portion may extend into the inside of the notch.

A method for manufacturing an optical connector according to one aspect of the present invention includes a step of accommodating the spring inside the housing from the outside in the radial direction, and then accommodating the ferrule unit inside the housing through the first insertion opening.

The above aspects of the present invention provide an optical connector or a method for manufacturing an optical connector that can improve assembly workability.

1 is a perspective view of an optical connector according to an embodiment of the present invention. FIG. 2 is an exploded perspective view of the optical connector of FIG. 1 . FIG. 2B is an exploded view of the ferrule unit of FIG. 2A. 3 is a cross-sectional view taken along the line III-III of FIG. 1. FIG. 4 is a view seen from the direction IV in FIG. 3, with the coupling omitted. 5A to 5C are diagrams illustrating a manufacturing method of the optical connector according to the embodiment. FIG. 5B is a diagram illustrating a process following FIG. 5A. FIG. 11 is a perspective view of a ferrule unit in an optical connector according to a first modified example of the present embodiment. 1 is a cross-sectional view of an optical connector according to a first modified example of the present embodiment. FIG. 11 is a cross-sectional view of an optical connector according to a second modified example of the present embodiment. FIG.

Hereinafter, the optical connector of this embodiment will be described with reference to the drawings.
As shown in FIGS. 1 and 2A, the optical connector 1A includes a ferrule unit 2, a housing 50, a spring S, a coupling 60, and a boot 70.
As shown in Fig. 2B, the ferrule unit 2 includes a ferrule body 10, a holding member 20, a biasing member 30, pressing members 40A and 40B, and a first optical fiber F1 (see Fig. 3). A fiber hole 11 is formed in the ferrule body 10, and the first optical fiber F1 is inserted into the inside of the fiber hole 11. The ferrule body 10 has a connection end face 12 in which the fiber hole 11 opens. The first optical fiber F1 is exposed at the connection end face 12. Note that the first optical fiber F1 is usually inserted and fixed in the ferrule body 10, and is therefore also called an inserted optical fiber.

(Direction definition)
In this specification, the direction in which the fiber hole 11 extends is referred to as the axial direction X. In the axial direction X, the connection end face 12 side (+X side) as viewed from the ferrule body 10 is referred to as the front or tip side, and the opposite side (-X side) is referred to as the rear or base side. As viewed from the axial direction X, the direction intersecting the central axis of the fiber hole 11 is referred to as the radial direction, and the direction going around the central axis is referred to as the circumferential direction.

As shown in FIG. 1, the coupling 60 is formed in a rectangular tubular shape extending in the axial direction X. When the optical connector 1A is assembled, the ferrule body 10 protrudes forward from the coupling 60. A cap for protecting the connection end face 12 may be attached to the front end of the ferrule body 10. In this case, it is possible to prevent dirt and the like from adhering to the first optical fiber F1 exposed at the connection end face 12. As shown in FIG. 3, the coupling 60 is formed with insertion holes 61 and 62 for inserting a wedge member (not shown).

The ferrule body 10 has a cylindrical shape extending along the axial direction X. However, the shape of the ferrule body 10 can be appropriately changed, and may be, for example, a rectangular column shape. As shown in FIG. 3 , the first optical fiber F1 extends rearward from the ferrule body 10.
The holding member 20 holds the ferrule body 10. As shown in Fig. 3, the holding member 20 has a flange portion 21 and a fiber holding portion 22. The flange portion 21 has a circular tubular shape extending in the axial direction X. The rear end of the ferrule body 10 is fitted inside the flange portion 21. The flange portion 21 has a first seating surface 23 facing rearward. A spring S is in contact with the first seating surface 23 (see Fig. 4).

A pair of restricting grooves 21a recessed radially inward are formed on the outer peripheral surface of the flange portion 21 (see FIG. 2B). Each restricting groove 21a extends along the axial direction X. A pair of restricting protrusions 26 (see FIG. 5A) formed on the housing 50 fit into each restricting groove 21a, thereby restricting rotation of the retaining member 20 relative to the housing 50. However, the shape of the flange portion 21 may be modified as appropriate.

As shown in FIG. 3, the fiber holding portion 22 extends rearward from the flange portion 21. A fiber groove 22a is formed in the fiber holding portion 22 for holding the first optical fiber F1 and the second optical fiber F2, which is another optical fiber. With the first optical fiber F1 and the second optical fiber F2 positioned by the fiber groove 22a, the rear end face of the first optical fiber F1 and the front end face of the second optical fiber F2 are abutted against each other. This optically connects the first optical fiber F1 and the second optical fiber F2.

The outer diameter of the fiber holding portion 22 is smaller than the outer diameter of the flange portion 21. In other words, the flange portion 21 protrudes radially outward from the fiber holding portion 22. The flange portion 21 is the portion of the ferrule unit 2 that is located radially outward. More specifically, the diameter of the outer peripheral surface of the flange portion 21 is the maximum outer diameter of the ferrule unit 2. Pressing members 40A and 40B abut against the fiber holding portion 22. Pressing member 40A is located forward of pressing member 40B.

The biasing member 30 is, for example, a U-shaped clip, formed in a semi-cylindrical shape by an elastic material such as metal, and is elastically deformable. The biasing member 30 biases the pressing members 40A, 40B toward the fiber holding portion 22, and the optical fibers F1, F2 are sandwiched between the fiber holding portion 22 and the pressing members 40A, 40B. As a result, the first optical fiber F1 inserted in the ferrule body 10 and the second optical fiber F2, which is the other optical fiber to be connected, are fixed to the ferrule unit 2 and maintained in an optically connected state. When a wedge member (not shown) is inserted between the fiber holding portion 22 and the pressing members 40A, 40B through the insertion holes 61, 62 of the coupling 60, the gap between the pressing members 40A, 40B and the fiber holding portion 22 widens. Therefore, the fixation of the optical fibers F1, F2 can be released.
In this manner, the component in which the optical fiber F1 (inserted optical fiber) and F2 (other optical fiber) are fixed to the ferrule unit 2 by the fiber holding portion 22 and the biasing member 30 is generally referred to as a mechanical splice element (or sometimes simply referred to as an element).

As shown in FIG. 2A, the boot 70 is cylindrical and extends in the axial direction X. A cylindrical screw member 71 is fixed to the inside of the front end of the boot 70. A female screw portion is formed on the inner peripheral surface of the screw member 71. An outer cover 72 extends rearward from the boot 70. The outer cover 72 houses the second optical fiber F2 inside. The second optical fiber F2 is covered by a coating layer C. However, the front end of the second optical fiber F2 is not covered by the coating layer C, and the second optical fiber F2 is exposed. This exposed portion is inserted into the fiber groove 22a of the ferrule unit 2.

2A, the housing 50 is cylindrical and extends in the axial direction X, and accommodates at least a portion of the ferrule unit 2 therein. In this embodiment, the front end of the ferrule body 10 protrudes forward from the housing 50, but the entire ferrule unit 2 may be accommodated in the housing 50. As shown in FIG. 2A and FIG. 3, the housing 50 has a first insertion opening 51, a second insertion opening 52, a third insertion opening 53, a pair of locking pieces 54, and a second seat surface 55. The first insertion opening 51 is an opening at the front of the housing 50, and the second insertion opening 52 is an opening at the rear of the housing 50. The inner diameter of the first insertion opening 51 is larger than the maximum outer diameter of the ferrule unit 2 (the outer diameter of the outer peripheral surface of the flange portion 21). Therefore, the ferrule unit 2 can be inserted into the housing 50 through the first insertion opening 51.

The inner diameter of the second insertion port 52 is larger than the outer diameter of the coating layer C that covers the second optical fiber F2. Therefore, the second optical fiber F2 can be inserted into the housing 50 through the second insertion port 52. The second insertion port 52 is cylindrical and extends in the axial direction X, and has a male thread formed on its outer circumferential surface. The female thread of the screw member 71 is screwed into the male thread of the second insertion port 52, thereby joining the housing 50 and the boot 70.

As shown in FIG. 2A, the third insertion opening 53 opens on the side surface (the surface facing radially outward) of the housing 50. The third insertion opening 53 is formed so that the spring S can be inserted into the housing 50 from the radially outer side.

The pair of locking pieces 54 are plate-shaped extending in the axial direction X. Each locking piece 54 is elastically deformable radially outward from the front end of the locking piece 54. The locking pieces 54 are located forward of the third insertion port 53. As shown in FIG. 3, the pair of locking pieces 54 are arranged to sandwich the ferrule body 10 between them in the radial direction. The rear end of each locking piece 54 is formed with an abutment portion 54a that protrudes radially inward. The dimension between the abutment portions 54a is smaller than the outer diameter of the flange portion 21. Each abutment portion 54a has an inclined surface 54b and an abutment surface 54c facing rearward. The inclined surface 54b is inclined radially inward as it approaches rearward.

The second seating surface 55 is formed inside the housing 50 and faces forward. As shown in Fig. 4, a spring S compressed in the axial direction X is disposed between the first seating surface 23 and the second seating surface 55. With this configuration, the holding member 20 receives a forward biasing force from the spring S.
The contact surface 54c of the housing 50 contacts the flange portion 21 from the front. Therefore, the holding member 20, which is biased forward by the spring S, is prevented from falling off the housing 50 in the forward direction.

Next, an example of an assembly method (manufacturing method) for the optical connector 1A configured as described above will be described.

First, the spring S is accommodated in the housing 50 through the third insertion opening 53 from the outside in the radial direction.
Next, as shown in Fig. 5A, the ferrule unit 2 is inserted into the housing 50 from the front through the first insertion opening 51. At this time, the first optical fiber F1 is provided in the ferrule unit 2, but the second optical fiber F2 is not provided. When the ferrule unit 2 is moved rearward by a predetermined distance, the flange portion 21 abuts against the inclined surfaces 54b of the pair of abutment portions 54a. When the ferrule unit 2 is further moved rearward, the inclined surfaces 54b are pressed, causing the locking pieces 54 to elastically deform radially outward, and the interval between the abutment portions 54a increases.

As shown in FIG. 5B, when the ferrule unit 2 is further moved rearward, the spring S abuts against the first seat surface 23, the flange portion 21 moves rearward over the abutment portion 54a, and the locking piece 54 is restored and deformed toward the inside in the radial direction. As a result, the holding member 20 is biased forward by the spring S, and the flange portion 21 abuts against the abutment surface 54c, restricting the forward movement of the holding member 20.

Then, the optical connector 1A is completed by performing a process of inserting the second optical fiber F2 from the rear into the fiber groove 22a of the ferrule unit 2 and a process of attaching the coupling 60, etc.

As described above, the optical connector 1A of this embodiment includes a ferrule unit 2 including a ferrule body 10 having a fiber hole 11 and a connection end face 12 where the fiber hole 11 opens, a housing 50, and a spring S. When the connection end face 12 side of the fiber hole 11 in the axial direction X is the front and the opposite side is the rear, the ferrule unit 2 holds the first optical fiber F1 inserted into the fiber hole 11 and extending rearward from the ferrule body 10 so as to be connectable to another optical fiber (second optical fiber F2). The housing 50 has a first insertion port 51 through which the ferrule unit 2 can be inserted from the front and a second insertion port 52 through which the second optical fiber F2 can be inserted from the rear, and accommodates at least a portion of the ferrule unit 2 inside. The spring S is accommodated inside the housing 50 and urges the ferrule unit 2 forward within the housing 50. When viewed from the axial direction X, the direction intersecting the central axis of the fiber hole 11 is taken as the radial direction, the ferrule unit 2 has a flange portion 21 which is the part of the ferrule unit 2 located at the outermost radial position, and the housing 50 has a locking piece 54 which is elastically deformable in the radial direction, and the locking piece 54 has an abutment portion 54a formed thereon which abuts against the flange portion 21 from the front.

According to the above configuration, the abutment portion 54a of the housing 50 abuts against the flange portion 21 from the front, preventing the ferrule unit 2 biased by the spring S from falling forward from the housing 50. When manufacturing the optical connector 1A, the ferrule unit 2 is inserted into the housing 50 from the front, causing the locking piece 54 to elastically deform and the abutment portion 54a to abut against the flange portion 21 from the front. This allows the ferrule unit 2 to be biased forward by the spring S and to be movable backward within the housing 50. This improves the workability when assembling the optical connector 1A.

Furthermore, the flange portion 21 has a first seat surface 23 that contacts the spring S, and also contacts the contact surface 54c of the contact portion 54a. In this way, by having the flange portion 21 contact both the spring S and the contact portion 54a, the number of parts required to hold the ferrule unit 2 in a forward biased state is reduced, and costs can be reduced.

In addition, the housing 50 has a third insertion opening 53 through which the spring S can be inserted into the housing 50 from the outside in the radial direction. This makes it easier to accommodate the spring S in the housing 50.

The manufacturing method of the optical connector 1A of this embodiment also includes a step of accommodating the spring S from the outside in the radial direction inside the housing 50, and then accommodating the ferrule unit 2 inside the housing 50 through the first insertion opening 51. By adopting such a manufacturing method, the workability of assembling the optical connector 1A is improved.

The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

(First Modification)
For example, as shown in FIG. 6, a pair of notches 21b may be formed in the flange portion 21. The notches 21b are recessed radially inward from the outer peripheral surface of the flange portion 21 and open forward. Furthermore, as shown in FIG. 7, the abutting portion 54a may enter the inside of the notch 21b. In this case, the abutting surface 54c of the abutting portion 54a abuts against the inner surface (front-facing surface) of the notch 21b, thereby restricting the ferrule unit 2 from falling forward from the housing 50. Furthermore, the abutting portion 54a enters the notch 21b, so that the rotation of the holding member 20 can be restricted by the abutting portion 54a. In FIG. 6 and FIG. 7, the pair of abutting portions 54a enter the pair of notches 21b, respectively. Moreover, the restricting grooves 21a and the notches 21b are alternately arranged at substantially equal intervals in the circumferential direction. However, the number of the notches 21b and the abutting portions 54a can be changed as appropriate, and the restricting groove 21a does not have to be provided.

(Second Modification)
8, the spring S does not have to be in contact with the flange portion 21. In the example of Fig. 8, the first seating surface 23 is formed at the rear end of the fiber holding part 22. Also, the second seating surface 55 is formed on the inner surface of the housing 50 in a portion facing the first seating surface 23 in the axial direction X. Even with this configuration, it is possible to insert the ferrule unit 2 from the front of the housing 50.

(Other Modifications)
In the above embodiment, the optical connector 1A is a single-core connector. However, the optical connector 1A may be a multi-core connector. In this case, the ferrule body 10 has a plurality of fiber holes 11, and a first optical fiber F1 is inserted into each fiber hole 11. Furthermore, a plurality of second optical fibers F2 are housed in the outer jacket 72, and the ferrule unit 2 is configured to hold the plurality of first optical fibers F1 and the plurality of second optical fibers F2 in an optically connected state.

In addition, the components in the above-described embodiments may be replaced with well-known components as appropriate without departing from the spirit of the present invention, and the above-described embodiments and variations may be combined as appropriate.

1A...Optical connector 2...Ferrule unit 10...Ferrule body 11...Fiber hole 12...Connection end surface 21...Flange portion 50...Housing 51...First insertion port 52...Second insertion port 53...Third insertion port 54...Latching piece 54a...Abutment portion F1...First optical fiber F2...Second optical fiber S...Spring X...Axial direction

Claims (4)

a ferrule unit including a ferrule body having a fiber hole and a connection end face in which the fiber hole opens, the ferrule unit holding a first optical fiber inserted into the fiber hole and extending rearward from the ferrule body so as to be connectable to another optical fiber when the connection end face side in the axial direction of the fiber hole is defined as a front side and the opposite side is defined as a rear side;
a housing having a first insertion opening into which the ferrule unit can be inserted from the front and a second insertion opening into which the other optical fiber can be inserted from the rear, the housing accommodating at least a portion of the ferrule unit therein;
a spring that is accommodated inside the housing and biases the ferrule unit forward within the housing,
When viewed from the axial direction, a direction intersecting the central axis of the fiber hole is defined as a radial direction.
the ferrule unit has a flange portion which is a portion of the ferrule unit located outermost in the radial direction,
The housing has a locking piece that is elastically deformable in the radial direction, and a contact portion is formed on the locking piece that contacts the flange portion from the front ,
the housing has a third insertion opening through which the spring can be inserted into the housing from an outer side in the radial direction,
An optical connector , wherein the first insertion opening, the second insertion opening, the third insertion opening, and the locking piece are formed in a single member serving as the housing. The optical connector according to claim 1, wherein the flange portion contacts the spring and the abutment portion. A notch is formed in the flange portion,
3. The optical connector according to claim 1, wherein the contact portion is disposed inside the notch. A method for manufacturing the optical connector according to any one of claims 1 to 3 , comprising the steps of:
A method for manufacturing an optical connector, comprising the steps of accommodating the spring inside the housing from the outside in the radial direction, and then accommodating the ferrule unit inside the housing through the first insertion opening.

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