WO2008108582A1

WO2008108582A1 - Field-installable optical connector

Info

Publication number: WO2008108582A1
Application number: PCT/KR2008/001258
Authority: WO
Inventors: Oh Joon Kwon; Jin Seong Yang; Yong Han Jeon; Myung Oan Kim; Chan Woo Park; Sung Ho Kim; Ho Seok Han; Ji Hoon Seo
Original assignee: Sehf-Korea Co., Ltd.; Novaoptics Co., Ltd.
Priority date: 2007-03-05
Filing date: 2008-03-05
Publication date: 2008-09-12

Abstract

The present invention provides a field-installable optical connector which can easily and stably connect a main wire (A) of a ferrule 30 to a main wire (B) of an optical cable in the field and can be reused. In the present invention, a main wire connecting member 300 is fixedly- connected to a plug 200 by a fixing cap 400. The main wire connecting member 300 includes a lower plate 310 and an upper plate 320. The lower plate 310 includes insertion grooves connected to each other and receiving and connecting a main wire, a coated main wire and an element wire, respectively. The main wire connecting member 300 is formed with a taper shape, and an inner diameter of a fixing member 600 for fixing the middle portion of the main wire connecting member 300 also has a taper shape. An end portion of the main wire connecting member projects from the fixing member 600, and the fixing clip 700 is detachably connected to the fixing member 600 and the main wire connecting member 300 such that an insertion groove for fixing the optical cable projecting from the end portion of the main wire connecting member 30 is formed.

Description

[DESCRIPTION]

[invention Title]

FIEID-INSTALIABLE OPTICAL CONNECTOR

[Technical Field]

The present invention relates to an optical connector and, more particularly, to a field-installable optical connector which can carry out the connection of optical fibers stably and easily in the field and can be reused.

[Background Art]

A fiber-to-the-home (FTTH) system, in which optical cables are directly connected to homes to provide various information including broadcast and communications to customers, has been proposed and applied to a newly-built apartment and the like.

In the FTTH system, the optical cable is reached at the surface of the inner wall of the home of the customer, for example, and its end is closed with a connector and installed on the surface of the inner wall. At this time, a worker introduces the optical cable into the home by setting the length of the optical cable to be several meters longer than the actually measured length. Then, the worker cuts the optical cable in the home, assembles an optical connector to its end, connects the optical connector to an optical adapter, and installs the same on the inner wall of the home .

Meanwhile, an optical fiber comprises a core layer and a cladding layer, which are generally called a main wire or core wire. Such a main wire has a diameter of approximately 125 μm. A coating layer having a thickness of approximately 250 μm is covered on the outer circumference of the main wire, which is called a coated main wire. An exterior covering having a thickness of approximately 900 μm is coated on the outer circumference of the coated main wire, which is called an element wire. Then, a jacket formed of PVC, for example, is coated on the outer circumference of the element wire via a buffering material such as Kevlar (aramid yarn) for the improvement of tensile strength. The optical fiber transmits and receives a desired signal through light transmitted via the core layer. Accordingly, it is necessary to accurately align the main wires of the optical cable in order to minimize the transmission loss of light during construction of the optical cable.

FIGS. IA and IB are diagrams illustrating the structure of a conventional field-installable optical connector which connects optical cables through the above- described main wire alignment process, in which FIG. IA is an assembled cross-sectional view of the conventional field- installable optical connector and FIG. IB is an exploded cross-sectional view thereof.

As shown in the figures, the conventional field- installable optical connector comprises a housing 10 and a plug 20 inserted into the housing 10. The plug 20 includes a ferrule receiving hole 21 in which a ferrule 30 is received, and a main wire connecting member receiving hole 22 in which a main wire connecting member 40 is received. The ferrule 30 and the main wire connecting member 40 are fixedly connected by epoxy resin, for example. A C-shaped clip 50 is connected to the outside of the main wire connecting member 40. Moreover, a fixing member 70 is connected to the plug 40 while elastically supporting the main wire connecting member 40 in one direction through a spring 60 disposed inside thereof, and a free end of the fixing member 70 is sealed by a protective cover 80.

The main wire connecting member 40 is formed in a clip shape. As shown in FIG. 2, the main wire connecting member 40 includes a cut groove 40a formed along the longitudinal direction thereof and a main wire insertion hole 41 formed inside the cut groove 40a. Accordingly, when the C-shaped clip 50 is connected to the main wire connecting member 40, the inner diameter (r) of the main wire insertion hole 41 becomes smaller and thus the main wires disposed inside the main wire insertion hole 41 are stably fixed. In the optical connector having the above-described structure, a main wire (A) of the ferrule and a main wire (B) of the optical cable are inserted into the main wire insertion hole 41 of the main wire connecting member 40 to be closely aligned and then the C-shaped clip 50 is connected to the main wire connecting member 40, thus stably connecting both the main wires (A and B) . Subsequently, the resulting assembly is fixedly connected to the plug 20 through the fixing member 70, and the protective cover 80 is finally connected to the fixing member 70, thus stably connecting the optical cable with respect to the main wire (A) of the ferrule.

However, the above-described structure has some drawbacks in that, since the worker determines whether or not the main wires are normally connected only with the worker' s hand sense, the wire connection cannot be done precisely and, if the wire connection is not done correctly, the assembling process of the optical connector should be repeated. Moreover, since the C-shaped clip 50 is fixedly connected to the wire connecting member 40 and the fixing member 70 is fixedly connected to the plug 20, in the case where the main wire (A) of the ferrule and the main wire (B) of the optical cable are not connected correctly, or in the case where the connection of the optical cable should be repeated by other necessities, the optical connector in which the main wires have been completely connected should be broken down and the operation should be repeated using a new optical connector. Meanwhile, Korean Patent No. 10-0507543 discloses a field-installable optical connector capable of being reused.

FIGS. 3A and 3B are diagrams illustrating the structure of the conventional field-installable optical connector disclosed in the above patent, in which FIG. 3A is an assembled cross-sectional view and FIG. 3B is an exploded cross-section view thereof. In FIGS. 3A and 3B, substantially the same elements as those shown in FIGS. IA and IB have the same reference numerals, and their detailed description will be omitted. In the optical connector as shown in FIGS. 3A and 3B, a flange 31 is fixedly connected to a ferrule 30, which constitute a main wire aligning member 90. The flange 31 is inserted and fixed to a flange holder 40' a of a main wire connecting member 40' . The main wire connecting member 40' is formed in a clip shape, the same as the optical connector of FIG. 1, and a main wire insertion hole 41' , into which a main wire (B) of the optical cable is inserted, is formed in the center portion thereof. In particular, the main wire (B) and an element wire (C) of the optical cable are inserted into the main wire insertion hole 41' . That is, the main wire insertion hole 41' has a diameter capable of receiving the element wire (C) of the optical cable.

A fixing member 70' is inserted into the outside of the main wire connecting member 40' and fixedly connected to a plug 20. The flange 31 is elastically supported to the fixing member 70' by means of a spring 60' .

A tightening member 50' is inserted into the outside of the main wire connecting member 40' to surround the main wire connecting member 40' . In this case, the tightening member 50' is detachably connected to the main wire connecting member 40' . A protective cover 80 is inserted into the outside of the tightening member 40' to surround a free end of the tightening member 40' and connected to the fixing member 70' In the above-described structure, the tightening member 50' is detachably connected to the main wire connecting member 40' to fix the element wire (C) inserted into the main wire connecting member 40' . Accordingly, after separating the tightening member 50' from the main wire connecting member 40', the main wire (B) of the optical cable can be repeatedly connected. That is, it is possible to reuse the optical connector.

Moreover, FIG. 4 is an exploded cross-sectional view showing a field-installable optica L connector having another structure disclosed in the above-cited reference. As shown in FIG. 4, a ferrule receiving hole 31a for receiving and fixing a ferrule 40' b is included in a flange 31 constituting a main wire aligning member 90' , and the ferrule 40' b is inserted into a flange holder 40' a of a main wire connecting member 40' . The other elements are substantially the same as those shown in FIGS. 3A and 3B.

In the above-described structure, a main wire (A) of the ferrule is inserted into the main wire connecting member 40' through the ferrule 30 of the main wire aligning member 90' and a main wire (B) of the optical cable is inserted into the main wire connecting member 40' through a protective cover 80 and a tightening member 50' such that both the main wires (A and B) are connected to each other in a main wire insertion hole 41' of the main wire connecting member 40' .

In the structure of FIG. 4, the main wire (A) of the ferrule is inserted into the main wire connecting member 40' through the ferrule 30 of the main wire aligning member 90' so as to eliminate the inconvenience that the main wire (B) of the optical cable, inserted from the protective cover 80 into the main wire alignment member 90 and led to the outside of a front end of the ferrule 30, should be cut and ground in the structure of FIGS. 3A and 3B.

However, the above-described conventional optical connectors have the following drawbacks. 1. In the conventional optical connectors, the main wire connecting member 40' for connecting the main wires (A and B) is formed in a clip shape and the diameter of the main wire insertion hole 41' is set to a diameter corresponding to the element wire (C) .

Accordingly, in the conventional optical connector, the main wire connecting member 40' cannot stably support the main wires, and thus the main wire aligning member 90 is required for the alignment of the wires. That is, additional elements such as the flange 31 and the ferrule 40'b are required.

Moreover, in the structure of FIG. 4, since the diameter of the main wire insertion hole 41' is set to be larger than that of the main wires (A and B) inserted thereinto, the optical alignment between both the main wires (A and B) is not done precisely. Moreover, in the case where the tightening member 50' is connected to the main wire connecting member 40' , the main wires (A and B) , especially, the connection portion of the main wires (A and B) is not fixed and supported stably in the main wire insertion hole 41' . Accordingly, the optical alignment between the main wires (A and B) may be damaged by external vibration or impact.

2. In the conventional optical connectors, the main wire connecting member 40' for connecting the main wires (A and B) is formed in a clip shape and the tightening member 50' for tightening the main wire connecting member 40' is detachably connected to the main wire connecting member 40' . Accordingly, the main wire (B) of the optical cable may not be stably fixed in the main wire connecting member 40' .

That is, in the structure shown in FIG. 1, the main wire connecting member 40 in a clip shape is firmly fixed by means of the C-shaped clip 50. In this case, the C-shaped clip 50 is inserted in the perpendicular direction to the main wire connecting member 40. Accordingly, the diameter of the C-shaped clip 50 is set to be smaller than that of the main wire connecting member 40 to firmly tighten the main wire connecting member 40.

However, the conventional optical connectors as shown in FIGS. 3 and 4 have the following drawbacks:

(1) Only the element wire (C) is fixed by the main wire connecting member 40' ;

(2) Since the tightening member 50' is inserted into the longitudinal direction of the main wire connecting member 40" , it is impossible to set the clamping force of the tightening member 50' with respect to the main wire connecting member 40' to more than a predetermined strength in view of the detachability; and

(3) Since the length of the element wire (C) inserted into the inside of the main wire connecting member 40' is restricted to less than a predetermined length, the clamping force between the main wire insertion hole 41' and the element wire (C) is not sufficiently ensured.

Accordingly, in the optical connectors as shown in FIGS. 3 and 4, the main wire (B) and the element wire (C), i.e., the optical cable may be separated from the optical connector even when a relatively low external tensile force is applied to the optical connector.

3. In the conventional optical connectors, since the connections between the main wires (A and B) through the main wire connecting members 40 and 40' are made only with the worker's hand sense, the operation accuracy is low.

4. In the conventional optical connectors, since the connection portions of the main wires (A and B) are not supported inside the main wire connecting members 40 and 40', the alignment state between the main wires (A and B) may be damaged when the C-shaped clip 50 or the tightening member 50' is connected thereto after the alignment of the main wires (A and B) during operations.

[Disclosure] [Technical Problem]

Accordingly, the present invention has been made in an effort to solve the above-described drawbacks. An object of the present invention is to provide a field-installable optical connector having excellent field-installation characteristics and capable of being reused.

Another object of the present invention is to provide a field-installable optical connector capable of connecting optical cables stably and firmly.

[Technical Solution]

The present invention provides a field-installable optical connector, in which a main wire of a ferrule and a main wire of an optical cable are connected in an optical alignment state, the field-installable optical connector comprising: a housing; a plug inserted and fixed to the housing; a ferrule to which the main wire of the ferrule is connected; a main wire connecting member including a ferrule holder formed on a front end thereof to connect the ferrule and connecting and fixing the main wire of the ferrule and the main wire of the optical cable; a fixing cap elastically supporting the main wire connecting member and fixedly connected to the plug; a fixing member including a connecting member insertion hole, into which the main wire connecting member is detachably inserted, and connected to the fixing cap; and a fixing clip detachably connected to an end portion of the main wire connecting member and fixedly maintaining the optical cable led from the main wire connecting member. The fixing clip may include a clip portion having first and second clip plates, separately formed along the longitudinal direction that the optical cable is inserted, and a connecting means for connecting and separating the first and second clip plates, in which a connecting member receiving hole connected to the end portion of the main wire connecting member is connected to an optical cable receiving hole for fixing the optical cable projecting from the end potion of the main wire connecting member. The clip portion may further include a fixing member receiving hole connected to an end portion of the fixing member.

A step height may be formed along the inner circumference of the connecting member receiving hole, and a connecting groove connected to the step height may be provided on the end portion of the main wire connecting member.

The optical cable receiving hole may include a first receiving hole for fixing an element wire coated with a yarn and a second receiving hole for fixing the optical cable coated with a jacket, and a plurality of projections for fixing the yarn may be provided on the opposite surface of the first and second clip plates corresponding to the first receiving hole. A plurality of bent portions having a shape corresponding to each other may be provided on the opposite surface of the first and second clip plates corresponding to the first receiving hole.

The connecting means may be hinge-connected to at least one of the first and second clip plates of the clip portion.

The connecting means may be formed into a C-shaped clip.

The first clip plate or the second clip plate may be integrally connected to the inside of the connecting means.

The connecting means may include a connecting wing hinge-connected to both the top and the bottom of the clip portion or to at least one of them.

First and second guide pins may be provided on the top of the first and second clip plates, and the connecting means may include guide holes having an oval shape provided in positions corresponding to the first and second guide pins .

A locking lever including a locking ring may be rotatably provided on the top of at least one of the first and second clip plates, and a locking projection connected to the locking ring may be provided on the top of the other clip plate.

A plurality of projections may be formed on the opposite surface of the clip portion and the connecting means such that a clamping force between the first and second clip plates is increased when the clip portion is connected by the connecting means.

The main wire connecting member may include first and second plates, separately formed along the longitudinal direction that the main wire is inserted, the first plate may include first and second insertion grooves, the first insertion groove, connected to the ferrule holder and inserting the main wire, being connected to the second insertion groove for inserting the element wire, the first insertion groove having a V-shaped cross section, and the second plate may include a third insertion groove formed in a position corresponding to the second insertion groove.

A forth insertion groove for inserting a coated main wire may be further included between the first and second insertion grooves, the forth insertion groove having a V- shaped cross section.

At least two point projections may be provided on the outer circumference of the main wire connecting member. The main wire connecting means may have a taper shape and the connecting member insertion hole of the fixing member may have a taper shape corresponding to the main wire connecting member.

At least one of the first .and second plates may be formed of a transparent material. A C-shaped clip may be connected to the front end of the main wire connecting member.

A penetrating hole may be provided on the housing and the fixing cap, respectively, in a position corresponding to the region where the main wire of the ferrule and the main wire of the optical cable are connected.

[Description of Drawings]

FIGS. IA and IB are diagrams illustrating the structure of a conventional field-installable optical connector;

FIG. 2 is a diagram illustrating the structure of a main wire connecting member 40 of FIG. 1;

FIGS. 3A, 3B and 4 are diagrams illustrating the structure of a conventional optical connector capable of being reused;

FIG. 5 is an assembled perspective view of a field- installable optical connector in accordance with a preferred embodiment of the present invention; FIG. 6 is an exploded perspective view of the field- installable optical connector of FIG. 5;

FIG. 7 is an assembled cross-sectional view of the field-installable optical connector of FIG. 5;

FIG. 8 is an exploded cross-sectional view of the field-installable optical connector of FIG. 5; FIGS. 9A and 9B are an assembled perspective view and an exploded perspective view of a main wire connecting member 300 shown in FIG. 6;

FIGS. 1OA and 1OB are diagram illustrating the structure of a fixing clip 700 shown in FIG. 6; and

FIGS. HA to 14B are diagrams schematically showing other examples of the structure of the fixing clip shown in FIG. 6.

[Mode for Invention]

Hereinafter, preferred embodiments in accordance with the present invention will be described with reference to the accompanying drawings. The preferred embodiments are provided so that those skilled in the art can sufficiently understand the present invention, but can be modified in various forms and the scope of the present invention is not limited to the preferred embodiments.

FIGS. 5 to 8 are diagrams illustrating a field- installable optical connector in accordance with a preferred embodiment of the present invention, in which FIG. 5 is an assembled perspective view of the field-installable optical connector, FIG. 6 is an exploded perspective view of the field-installable optical connector, FIG. 7 is an assembled cross-sectional view of the field-installable optical connector, and FIG. 8 is an exploded cross-sectional view of the field-installable optical connector.

In the field-installable optical connector in accordance with the present invention, a plug 200 is fixedly inserted into a housing 100, and a main wire connecting member 300 is connected to the plug 200 by a fixing cap 400. The main wire connecting member 300 is elastically supported to the fixing cap 400 by means of a spring 500. A ferrule 30 is fixedly connected to a front end of the main wire connecting member 300, and a fixing member 600 is detachably inserted into a free end of the main wire connecting member 300. The fixing member 600 is detachably connected to the fixing cap 400.

The plug 200 is connected to the housing 100 to be moved in the longitudinal direction thereof. A connecting groove 110 for connecting the plug 200 to the housing 100 is formed on both lateral sides of the housing 100. A fixing projection 260 of the plug 200 is connected to the connecting groove 110. In particular, the length of the connecting grooves 110 is set to be larger than that of the pair of fixing projections 260 formed on the plug 200 so that the housing 100 may move a predetermined distance in with respect to the plug 200 along the longitudinal direction thereof.

Moreover, a guide projection 110a for connecting the present connector to the other connector is formed on the upper surface of the housing 100, and a penetrating hole 120 is provided on at least one of the upper and lower surfaces of the housing 100. The penetrating hole 120 is formed in a position corresponding to the region where the main wires are connected in the main wire connecting member 300. As will be described below, the worker can visually check the alignment and connection state of the main wires in the main wire connecting member 300 through the penetrating hole 120, or insert an external tool into the alignment region of the main wires through the penetrating hole 120 to temporarily fix the alignment region when assembling the optical connector using a jig and the like.

The plug 200 includes a fixing cap receiving hole 210 for receiving and fixing the fixing cap 400 and an optical outlet connecting hole 230 for connecting an optical outlet, not depicted. Moreover, the plug 200 includes a ferrule penetrating hole 220, through which the ferrule 30 penetrates from the fixing cap receiving hole 210 toward the optical outlet connecting hole 230. A fixing projection 270 connected to a rotation preventing projection 312 of the main wire connecting member 300 is formed on one side of the fixing cap receiving hole 210.

As described above, the pair of fixing projections 260 for connecting the plug 200 to the housing 100 is formed on both lateral sides of the plug 200, respectively, and a fixing cap connecting hole 250 for connecting the fixing cap 400 is formed thereon. A cut groove 240 for elastically fixing the fixing cap 400 is formed on the upper and lower surfaces of the plug 200, and a fixing cap connecting groove 280 connected to a connecting ring 450 of the fixing cap 400 to more firmly fix the fixing cap 400 is formed on the inner circumference of the plug 200.

A ferrule holder 311 for receiving and fixing the ferrule 30 is provided on the front end of the main wire connecting member 300. The rotation preventing projection 312 for preventing the main wire connecting member 300 from being rotated in the plug 200 is formed on the outer circumference of the ferrule holder 311. The rotation preventing projection 312 includes a connecting groove 312a connected to the fixing projection 270 provided in the fixing cap receiving hole 210 of the plug 200.

As shown in FIGS. 9A and 9B, the main wire connecting member 300 includes first and second plates 310 and 320. In the present embodiment, the first plate 310 corresponds to a lower plate and the second plate 320 corresponds to an upper plate. Moreover, the ferrule holder 311 may be integrally connected to one of the first and second plates 310 and 320; however, the ferrule holder 311 is integrally connected to the lower plate 310 in the present embodiment. The lower plate 310 includes a plurality of guide grooves 314 and the upper plate 320 includes a plurality of guide projections 322 in positions corresponding to the guide grooves 314. With such guide grooves 314 and the guide projections 322, the worker can easily connect the lower plate 310 to the upper plate 320.

A main wire insertion groove 313 is formed on the middle portion of the upper surface of the lower plate 310 along the longitudinal direction thereof. The main wire insertion groove 313 is connected to the inside of the ferrule holder 311. The main wire insertion groove 313 includes first to third insertion grooves 3131 to 3133. The first to third insertion grooves 3131 to 3133 are integrally connect to each other and have a width and a height different from each other. As described above, the main wire has a diameter of approximately 125 μm, the coated main wire has a diameter of approximately 250 μm, and the element wire has a diameter of approximately 900 μm. The first to third insertion grooves 3131 to 3133 have a size capable of receiving and fixing the main wire, the coated main wire and the element wire, respectively.

The first and second insertion grooves 3131 and 3132 have a V-shaped cross section, and the third insertion groove 3133 has a circular cross section and includes a projection 3133a having a triangular cross section in a direction perpendicular to the longitudinal direction thereof. In particular, the projection 3133a is inclined from the free end toward the rotation preventing projection

312 so that the element wire may be freely introduced from the free end to the main wire insertion groove 313 and the element wire introduced to the main wire insertion groove

313 may not be drawn out in the reverse direction.

Moreover, the portions of the upper plate 320 corresponding to the first and second insertion grooves 3131 and 3132 are formed evenly, and the portion of the upper plate 320 corresponding to the third insertion groove 3133 includes a fourth insertion groove 321 having the same shape as the third insertion groove 3133. The fourth insertion groove 321 also includes a projection 321a in the same manner as the third insertion groove 3133. Accordingly, the main wires (A and B) and the coated main wire disposed in the first and second insertion grooves 3131 and 3132 are depressed downward by the upper plate 320 and firmly fixed in the V-shaped groove, and the element wire (C) is closely fixed in the third and fourth insertion grooves 3133 and 321.

Moreover, at least two point projections 323 are formed on the outer circumference of the lower and upper plates 310 and 320 along the longitudinal direction thereof. Preferably, the point projection 323 is provided in positions corresponding to the first to third insertion grooves 3131 to 3133 one by one. With the point projections 323, the frictional force between the main wire connecting member 300 and the fixing member 600 is minimized and the clamping force between the lower plate 310 and the upper plate 320 of the main wire connecting member 300 is maximized.

As described above, in order to increase the clamping force between the lower plate 310 and the upper plate 320 of the main wire connecting member 300, the inner diameter of the fixing member 600 should be set to be smaller than the outer diameter of the main wire connecting member 300. However, if so, the frictional force between the main wire connecting member 300 and the fixing member 600 is highly increased, and thus the detachability of the fixing member 600 with respect to the main wire connecting member 300 is significantly reduced.

Meanwhile, if the inner diameter of the fixing member 600 is set to be larger than the outer diameter of the main wire connecting member 300, the detachability of the fixing member 600 with respect to the main wire connecting member 300 is improved; however, the clamping force between the lower plate 310 and the upper plate 320 of the main wire connecting member 300 is reduced.

In an ideal case, it is preferable that the outer diameter of the main wire connecting member 300 be set to be the same as the inner diameter of the fixing member 600. However, if so, the fixing member 600 cannot be practically connected to the main wire connecting member 300 by the frictional force between the main wire connecting member 300 and the fixing member 600.

Preferably, when the point projections 323 are formed on the outside of the main wire connecting member 300 and the inner diameter of the fixing member 600 is set to be an intermediate value between the outer diameter of the main wire connecting member 300 and the outer diameter of the point projections 323, the contact area between the fixing member 600 and the main wire connecting member 300 is reduced by the point projections 323, and thus the frictional force therebetween is reduced. Moreover, since the portion where the point projections 323 are provided on the main wire connecting member 300 has an outer diameter greater than that of the other portion, the lower plate 310 and the upper 320 are firmly tightened, thus improving the clamping force between the lower plate 310 and the upper plate 320.

In accordance with another preferred embodiment, the main wire connecting member 300 is formed to have a taper shape so that the outer diameter of the main wire connecting member 300 becomes smaller as it goes to the free end, and a connecting member insertion hole 620 of the fixing member 600 is formed to have a taper shape corresponding to that of the main wire connecting member 300.

In this case, it is possible to minimize the frictional force between the main wire connecting member 300 and the fixing member 600 when the fixing member 600 is connected to the main wire connecting member 300, thus closely connecting the main wire connecting member 300 to the fixing member 600.

Moreover, when the point projections 323 are formed on outer circumference of the main wire connecting member 300, it is possible to improve the clamping force between the lower plate 310 and the upper plate 320 of the main wire connecting member 300.

Preferably, either the lower plate 310 or the upper plate 320 or both the lower and upper plates 310 and 320 of the main wire connecting member 300 may be formed of a transparent material. If so, the worker can visually check the connection state when connecting the main wires using the optical connector, and thus the alignment of the main wires can be carried out precisely.

Suitably, a connecting groove 324 connected to a step height 712a of a fixing clip 700 is provided on an end portion of the outer circumference of the main wire connecting member 300. Preferably, a C-shaped clip 330 is connected to a connecting groove 325 formed on the upper end of the main wire connecting member 300. In this case, the length of the C-shaped clip 330 is set to be smaller than that of the main wire (A) of the ferrule led into the main wire insertion groove 313. If the length of the C-shaped clip 330 is greater than that of the main wire (A) of the ferrule, the C-shaped clip 330 presses the connection region between the main wire (A) of the ferrule and the main wire (B) of an optical cable (S) , thus making it difficult to insert the main wire (B) to be closely adhered to the main wire (A) . The C-shaped clip 330 stably fixes the main wire (A) of the ferrule with respect to the main wire insertion groove 313 and, particularly, tightens the front end of the main wire connecting member 300 to widen the gap between the lower plate 310 and the upper plate 320 of the end portion thereof, thus making it easy to insert the main wire (B) into the main wire insertion groove 313.

The fixing cap 400 connects the main wire connecting member 300 to the plug 200 so that the main wire connecting member 300 may move a predetermined distance along the longitudinal direction thereof. The fixing cap 400 is formed in a cylindrical shape and includes a spring receiving hole 420 formed inside the front end thereof to receive the spring 500. The spring 500 elastically supports the rotation preventing projection 312 of the main wire connecting member 300.

An insertion projection 430 and the connecting ring 450 connected to the fixing cap connecting hole 250 and the fixing cap connecting groove 280, respectively, and a connecting ring 440 inserted and connected to a connecting groove 640 of the fixing member 600 are provided on the outer circumference of the fixing cap 400. In this case, a connecting groove 441 to be connected to a connecting projection 641 of the fixing member 600 is formed on the connecting ring 440. With the connecting rings 450 and 440, the worker can stably connect the fixing cap 400 to the plug 200 and the fixing member 600. Moreover, the connecting rings 450 and 440 generate a connection sound during the connection so that the worker can confirm the connection state.

Moreover, the fixing cap 400 includes a penetrating hole 410 formed in a position corresponding to the penetrating hole 120 of the housing 100. The penetrating hole 410 is formed in a position corresponding to the region where the main wires are connected in the main wire connecting member 300 like the penetrating hole 120. With the penetrating hole 410, the worker can visually check the alignment and connection state of the main wires in the main wire connecting member 300 or insert an external tool into the alignment region of the main wires to temporarily fix the alignment position of the main wire connecting member 300 when assembling the optical connector using a jig and the like.

The fixing member 600 includes a cut groove 610 formed in a position corresponding to the penetrating hole 410 of the fixing cap 400. Moreover, the fixing member 600 includes a fixing cap receiving hole 630 formed inside thereof to receive the lower portion of the fixing cap 400, and the connecting member insertion hole 620 connected to the fixing cap receiving hole 630 and fixing the main wire connecting member 300 inserted through.

The fixing cap connecting groove 640 and the connecting projection 641, connected to the connecting ring 440 and the connecting groove 441 of the fixing cap 400, are formed inside the fixing cap receiving hole 630. In this case, the fixing cap connecting groove 640 has a length in the longitudinal direction thereof greater than that of the connecting ring 440 so that the fixing member 600 may move along the longitudinal direction with respect to the fixing cap 400.

The connecting member insertion hole 620 has an inner diameter capable of properly pressing the lower plate 310 and the upper plate 320 of the main wire connecting member 300. Preferably, in the case where the main wire connecting member 300 is formed in a taper shape, the connecting member insertion hole 620 has a taper shape corresponding to that of the main wire connecting member 300.

Moreover, a connecting projection 650 for connecting the fixing clip 700 to the fixing member 600, which will be described below, is provided on the end portion of the fixing member 600.

The fixing member 600 is formed with a color that matches the kind of the optical connector.

The fixing clip 700 is provided to firmly maintain the connection state of the main wire connecting member 300 and the optical cable (S) so as to prevent the optical cable (S) from being separated from the main wire connecting member 300. Moreover, the fixing clip 700 firmly connects the assembly of the main wire connecting member 300 and the optical cable (S) to the fixing member 600 so as to stably maintain the connection state of the main wire connecting member 300, the fixing member 600 and the optical cable (S), thus stably maintaining the connection state of the optical connector of the invention. The fixing clip 700 includes a clip portion 710 that protects the end portion of the fixing member 600, is connected to the main wire connecting member 300, and fixes the optical cable (S) in which the main wire (B) is inserted into the main wire connecting member 300, and a connecting means 720 for stably maintaining the connection state of the clip portion 710.

The clip portion 710 includes a fixing member receiving hole 711 for fixing the end portion of the fixing member 600, a connecting member receiving hole 712 for receiving the end portion of the main wire connecting member 300 projecting to the outside of the fixing member 600, and an optical cable receiving hole 713 for receiving the optical cable (S) projecting to the outside of the main wire connecting member 300. A connecting groove 711a connected to the connecting projection 650 provided on the end portion of the fixing member 600 is provided on one end of the fixing member receiving hole 711. Accordingly, when the clip portion 710 is connected by the connecting means 720, the connecting projection 650 of the fixing member 600 is connected to the connecting groove 711a, and thus the fixing clip 700 is firmly fixed to the fixing member 600.

The connecting member receiving hole 712 includes the step height 712a having a diameter corresponding to that of the connecting groove 324 formed on the end portion of the outer circumference of the main wire connecting member 300. In this case, the inner diameter of the step height 712a is set to be smaller than that of the connecting groove 324. Accordingly, when the clip portion 710 is connected by the connecting means 720, the connecting groove 324 of the main wire connecting member 300 is adhered and fixed to the step height 712a, and thus the fixing clip 700 is firmly connected to the main wire connecting member 300.

The optical cable receiving hole 713 includes first and second receiving holes 7131 and 7132. The first receiving hole 7131 has a diameter capable of fixing the element wire (C) and the second receiving hole 7132 has a diameter capable of receiving the optical cable (S) . As can be seen from FIGS. 1OA and 1OB, a plurality of projections 7132a for pressing and fixing the optical cable (S) is provided on the inside of the second receiving hole 7132. As shown in FIGS. 1OA and 1OB, the clip portion 710 includes first and second clip plats 710a and 710b. A clearance groove 740a and a locking projection 740b are formed on each one end of the first and second clip plats 710a and 710b at a predetermined interval such that the second clip plate 710b is opened by a predetermined angle with respect to the first clip plate 710a. Moreover, when the first and second clip plates 710a and 710b are connected, they form the above-described fixing member receiving hole 711, connecting member receiving hole 712, and optical cable receiving hole 713 in the middle thereof.

In the first and second clip plates 710a and 710b, a plurality of triangular projections 714 is formed on both sides of the first receiving hole 7131 to correspond to each other, and bent portions 715a and 715b are formed to correspond to each other. Such projections 714 and bent portions 715a and 715b are provided to firmly fix the yarn (Y) that wraps the element wire (C) positioned in the first receiving hole 7131.

A guide projection 716 is provided on the outer surface of the first clip plate 710a, and a guide groove 717 is formed in a position, corresponding to the guide projection 716, of the second clip plate 710b such that the connection state of the first and second clip plates 710a and 710b is stably maintained.

The connecting means 720 is formed into a C-shaped clip to accommodate the clip portion 710. A hinge pin 721 is provided on both side surfaces of the end portion of the second clip plate 710b, and a hinge hole 721a connected to the hinge pin 721 is provided on both sides of the end portion of the connecting means 720. Accordingly, the second clip plate 710b can be rotated with respect to the connection means 720 through a hinge connection with the connecting means 720.

Moreover, first and second guide pins 722 and 723 are provided on both side surfaces of the first clip plate 710a at a predetermined interval along the longitudinal direction thereof to support the rotational movement of the first clip plate 710a, and first and second guide holes 722a and 723a in the shape of a long hole are provided on the connecting means 720 in positions corresponding to the guide pins 722 and 723. The first guide hole 722a is formed in a direction horizontal to the longitudinal direction and the second guide hole 723a is formed to be inclined with respect to the first guide hole 722a so as to support the rotational movement, i.e., the angular movement, of the first clip plate 710a. The first and second guide pins 722 and 723 and the first and second guide holes 722a and 723a are provided to guide the rotational movement of the first clip plate

710a and, at the same time, restrict the rotational movement of the first clip plate 710a within a predetermined angle. Moreover, it is possible to provide only each one of the first and second guide pins 722 and 723 and only each one of the first and second guide holes 722a and 723a instead of the two pins and two holes .

A connecting projection 724 is provided on both inside surfaces of an opening portion of the connecting means 720, and a connecting groove 718 is formed on both side surfaces, corresponding to the connecting projection 724, of the second clip plate 710b such that the clip portion 710 may be accommodated in the inside of the connecting means 720 and connected thereto.

Moreover, a connecting hole 731 (refer to FIG. 7) for connecting a screw 730 (also refer to FIG. 7) is formed on a surface corresponding to the first clip plate 710a of the connecting means 720, and a support plate 732, formed of a metal material, for example, is provided in a position corresponding to the connecting hole 731 of the first clip plate 710a. Accordingly, when the screw 730 is inserted into the connecting hole 731 and tightly screwed toward the clip portion 710 after the clip portion 710 is connected to the connecting means 720, it is possible to firmly connect the first clip plate 710a and the second clip plate 720a. The method of firmly connecting the first clip plate 710a and the second clip plate 720a is not limited to the above method. For example, it is possible to provide a projection on any one surface of the first clip plate 710a and the connecting means 720 so as to press and connect the clip portion 710 to the connecting means 720.

Moreover, the structures of the clip portion 710 and the connecting means 720 are not particularly limited, but various structures can be applied.

FIGS. 11 to 14 show examples of the structures of the clip portion 710 and the connection means 720 applicable to the present invention.

In FIG. 11, a first clip plate 710a of the clip portion 710 is integrally formed with the connecting means 720, and a locking projection 1100 is provided on an end portion of the connecting means 720. The second clip plate 710b is hinge-connected to the connecting means 720 via a hinge pin 721.

In this configuration, the second clip plate 710b is pressed and connected to the connecting means 720 through the locking projection 1100. The other elements are the same as those the above embodiment, and thus their detailed description will be omitted.

In FIG. 12A, the clip portion 710 is connected by a connecting wing 1200. In the clip portion 710 of FIG. 12A, first and second clip plates 710a and 710b are foldably connected to each other at their end portions. In this case, the first and second clip plates 710a and 710b might be connected through a hinge means. A hinge pin 1210 is provided on the other end portion of the first clip plate 710a and the connecting wing 1200 is connected thereto to be moved angularly. Moreover, a guide pin 1220 is provided on the other end of the second clip plate 710b, and a guide hole 1230 for guiding the guide pin 1220 in the shape of a long hole is provided in the connecting wing 1200. The guide hole 1230 and the guide pin 1220 are provided to guide the rotational movement of the second clip plate 710b and, at the same time, restrict the rotational movement of the second clip plate 710b within a predetermined angle. Especially, one end of the guide hole 1230 is positioned adjacent to the hinge pin 1210 and the other end thereof is positioned away from the hinge pin 1210 such that the clip portion 710 is opened and closed by the rotation of the connecting wing 1200.

In FIG. 12B, first and second connecting wings 1200a and 1200b are provided on the top and the bottom of the clip portion 710, respectively. Since the other elements are substantially the same as the above embodiment, they have the same reference numerals as FIG. 12A and their detailed description will be omitted. In FIG. 12C, first and second connecting wings 1200a and 1200b are provided on the top and the bottom of the clip portion 710, respectively, the same as FIG. 12B. However, in FIG. 12C, the first connecting wing 1200a is hinge- connected to the first clip plate 710a through a hinge pin 1210a, and the second connecting wing 1200b is hinge- connected to the second clip plate 710b such that the first and second connecting wings 1200a and 1200b are rotated in the opposite direction to each other to connect the clip portion 710. The other elements are substantially the same as those of FIG. 12B, and their detailed description will be omitted.

FIGS. 13A and 13B show another example of the fixing clip 700, in which FIG. 13A shows a state where the fixing clip 700 is connected and FIG. 13B shows a state where the fixing clip 700 is released. In FIGS. 13A and 13B, the bottoms of first and second clip plates 710a and 710b that constitute the clip portion 710 are foldably connected to each other, and guide pins 1310 and 1320 are provided on the middle of the top surface of the first and second clip plates 710a and 710b.

A rectangular connecting wing 1300 is provided on the top of the clip portion 710. Moreover, circular guide holes 1310a and 1310b are formed in positions corresponding to the guide pins 1310 and 1320 in the connecting wing 1300. The guide holes 1310a and 1310b have a generally oval shape. Accordingly, when the guide pins 1310 and 1320 are located in positions corresponding to a short axis of the guide holes 1310a and 1310b, the clip portion 710 is connected, whereas, when the guide pins 1310 and 1320 are located in positions corresponding to a long axis of the guide holes 1310a and 1310b, the clip portion 710 is released. The other elements are substantially the same as those of the above embodiment, and their detailed description will be omitted. FIGS. 14A and 14B show a modified structure of the fixing clip 700 of FIG. 13, in which FIG. 14A shows a state where the fixing clip 700 is connected and FIG. 14B shows a state where the fixing clip 700 is released.

In FIG. 14, a locking lever 1400 is rotatably connected on the top of a second clip plate 710b, and a locking ring 1410 is rotatably connected to the locking level 1400. Moreover, a locking projection 1420 to which the locking ring 1410 is locked is provided on the top of a first clip plate 710a. In this configuration, the locking ring 1410 is locked to the locking projection 1420 and then the locking lever 1400 is rotated to the opposite side of the locking projection 1420, thus connecting the clip portion 710.

Next, the assembly process of the field-installable optical connector having the above configuration will be described.

First, the ferrule 30 from which the main wire (A) extends a predetermined length is inserted and fixed to the ferrule holder 311 of the main wire connecting member 300. The worker cuts the optical cable led into the home in a necessary position and divides the front end of the optical cable (S) into the main wire (B) and the element wire (C) . In this case, a predetermined portion of the optical cable (S) positioned on the outside of the main wire connecting member 300 is covered with the yarn (Y) .

Then, the worker places the upper plate 320 on the lower plate 310 of the main wire connecting member 300 and connects the C-shaped clip 330 on the connecting groove 325 formed on the upper end of the main wire connecting member 300. At this time, the lower plate 310 and the upper plate 320 of the end portion of the main wire connecting member 300 are opened a predetermined interval by the C-shaped clip 330, thus facilitating the insertion of the main wire (B) .

The worker sequentially inserts the spring 500 and the fixing cap 400 into the main wire connecting member 300. Then, the worker pushes the fixing cap 400 into the inside of the plug 200 and connects the plug 200 to the housing 100. At this time, the spring 500 is received inside the fixing cap 400 to elastically support the main wire connecting member 300 in one direction.

In the above state, the worker sequentially inserts the front portion of the optical cable (S) through the fixing clip 700 and the fixing member 600 and then pushes the optical cable (S) into the main wire insertion groove 313 of the main wire connecting member 300 to align the main wire (A) of the ferrule and the main wire (B) of the optical cable (S) . At this time, in the case where the main wire connecting member 300 is formed of a transparent material, the worker can check the connection state of the main wires (A and B) , made in the inside of the main wire connecting member 300, with naked eyes through the penetrating hole 120 of the housing 100 and the penetrating hole 410 of the fixing cap 400.

Next, the worker pushes the fixing member 600 into the outside of the main wire connecting member 300 so that the connecting groove 441 of the connecting ring 400 formed on the fixing cap 400 may be engaged with the connecting projection 641 formed inside the fixing member 600.

Accordingly, the main wire (B) and the element wire (C) disposed in the main wire insertion groove 313 are adhered and fixed to the lower plate 310 and the upper plate 320 of the main wire connecting member 300. Especially, the clamping force between the lower plate 310 and the upper plate 320 of the main wire connecting member 300 is increased by the point projections 322 formed on the outer circumference of the main wire connecting member 300.

In the state where the fixing member 600 is connected to the main wire connecting member 300, the end portion of the main wire connecting member 300 is projected to the outside of the fixing member 600. Moreover, the element wire (C) wrapped by the yarn (Y) and the optical cable (S) coated with a jacket are drawn out to the outside of the end portion of the main wire connecting member 300.

In the above state, the worker arranges the end portion of the fixing member 600 and that of the main wire connecting member 300 in the fixing member receiving hole 711 and the connecting member receiving hole 712, respectively, formed on the clip portion 710 of the fixing clip 700. The worker disposes the element wire (C) wrapped with the yarn (Y) and the optical cable (S) , drawn out from the end portion of the main wire connecting member 300, in the optical cable receiving hole 712, and connects the clip portion 710 and the connecting means 720. With the connection between the clip portion 710 and the connecting means 720, the main wire connecting member 300, the fixing member 600, and the optical cable (S) are integrally and firmly adhered and connected to each other.

Moreover, since the main wire connecting member 300 is firmly connected to the plug 200 through the fixing cap 400, and the fixing clip 700 is firmly fixed to the main wire connecting member 300, the optical cable (S) can be stably fixed to the optical connector.

Meanwhile, as described above, in order to separate the assembled optical connector to connect a new optical cable, the worker separates the clip portion 710 of the fixing clip 700 from the connecting means 720, and then sequentially separates the fixing clip 700 and the fixing member 600 from the optical connector. In this state, the worker can draw out the optical cable (S) from the main wire connecting member 300 to the outside.

Moreover, as described above, the worker can reassemble the field-installable optical connector by inserting the new optical cable (S) into the main wire insertion groove 313 of the main wire connecting member 300 through the fixing clip 700 and the fixing member 600. According to the above embodiment, it is possible to connect the optical cable (S) to the optical connector by a simple operation that inserts the main wire (B) of the optical cable into the main wire connecting member 300, connects the fixing member 600, and then connects the fixing clip 700. Moreover, it is possible to separate the optical cable (S) from the optical connector by a simple operation that separates the fixing clip 700 from the optical connector and draws out the fixing member 600 from the main wire connecting member 300. That is, it is thus possible to realize the field-installable optical connector that can easily connect and separate the optical cable (S) to and from the optical connector in the field.

Moreover, since the first and second insertion grooves 3131 and 3132 for the insertion of the main wire have a V- shaped cross section and the third insertion groove 3133 for the insertion of the element wire includes the projections 3133a, the main wire and the element wire led into the main wire connecting member 300 can be firmly fixed in the main wire connecting member 300. Accordingly, the connection state between the main wire (A) of the ferrule and the main wire (B) of the optical cable (S) are stably maintained even in the case where a tensile force above a predetermined level is applied from the outside after the optical cable (S) is connected by the main wire connecting member 300. Furthermore, the yarn (Y) wrapping the element wire (C) of the optical cable (S) is firmly adhered and fixed to the fixing clip 700 by the projections 714 formed on both sides of the first receiving hole 7131 and by the bent portions 715a and 715b, and the optical cable (S) is pressed and fixed to the fixing clip 700 by the projections 7132a provided on the inside of the second receiving hole 7132. As a result, the optical cable (S) is firmly connected to the fixing clip 700. In addition, the main wire connecting member 300 is firmly connected to the plug 200 through the fixing cap 400, and the fixing clip 700 is firmly connected to the main wire connecting member 300 and the fixing member 600. As a result, the optical cable (S) is stably and firmly connected to the optical connector. Moreover, with the point projections 323 formed on the outer circumference of the main wire connecting member 300, it is possible to facilitate the attachment and detachment of the fixing member 300 with respect to the main wire connecting member 300 by minimizing the frictional force between the main wire connecting member 300 and the fixing member 600, and further it is possible to prevent the main wire of the optical cable (S) from being separated from the main wire connecting member 300 by maximizing the clamping force between the lower plate 310 and the upper plate 320 of the main connecting member 300. Furthermore, since the main wire connecting member 300 has a taper shape and the connecting member insertion hole 620 of the fixing member 600 has a taper shape corresponding to that of the main wire connecting member 300, it is possible to maximize the clamping force between the fixing member 600 and the main wire connecting member 300.

Additionally, since the main wire connecting member 300 is formed of a transparent material, and the penetrating holes 120 and 410 and the cut groove 610 are provided in the positions corresponding to the connection position of the main wire (A) of the ferrule and the optical cable (S) , the worker can accurately assemble the optical connector while checking the connection state of the main wires in the field.

The invention is not limited to the disclosed embodiments, but is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

[industrial Applicability] As described above, the present invention can provide the field-installable optical connector having excellent field-installation characteristics and capable of being reused and connecting the optical cables stably and firmly.

Claims

[CLAIMS]

[Claim l]

A field-installable optical connector, in which a main wire of a ferrule and a main wire of an optical cable are connected in an optical alignment state, the field- installable optical connector comprising: a housing; a plug inserted and fixed to the housing; a ferrule to which the main wire of the ferrule is connected; a main wire connecting member including a ferrule holder formed on a front end thereof to connect the ferrule and connecting and fixing the main wire of the ferrule and the main wire of the optical cable; a fixing cap elastically supporting the main wire connecting member and fixedly connected to the plug; a fixing member including a connecting member insertion hole, into which the main wire connecting member is detachably inserted, and connected to the fixing cap; and a fixing clip detachably connected to an end portion of the main wire connecting member and fixedly maintaining the optical cable led from the main wire connecting member.

[Claim 2] The field-installable optical connector of claim 1, wherein the fixing clip includes a clip portion having first and second clip plates, separately formed along the longitudinal direction that the optical cable is inserted, and a connecting means for connecting and separating the first and second clip plates, in which a connecting member receiving hole connected to the end portion of the main wire connecting member is connected to an optical cable receiving hole for fixing the optical cable projecting from the end potion of the main wire connecting member.

[Claim 3]

The field-installable optical connector of claim 2, wherein the clip portion further includes a fixing member receiving hole connected to an end portion of the fixing member.

[Claim 4]

The field-installable optical connector of claim 2, wherein a step height is formed along the inner circumference of the connecting member receiving hole, and a connecting groove connected to the step height is provided on the end portion of the main wire connecting member.

[Claim 5] The field-installable optica] connector of claim 2, wherein the optical cable receiving hole includes a first receiving hole for fixing an element wire coated with a yarn and a second receiving hole for fixing the optical cable coated with a jacket, and a plurality of projections for fixing the yarn is provided on the opposite surface of the first and second clip plates corresponding to the first receiving hole.

[Claim 6] The field-installable optical connector of claim 2, wherein a plurality of bent portions having a shape corresponding to each other is provided on the opposite surface of the first and second clip plates corresponding to the first receiving hole.

[Claim 7]

The field-installable optical connector of claim 2, wherein the connecting means is hinge-connected to at least one of the first and second clip plaites of the clip portion.

[Claim 8]

The field-installable optical connector of claim 2, wherein the connecting means is formed into a C-shaped clip.

[Claim 9] The field-installable optical connector of claim 2, wherein the first clip plate or the second clip plate is integrally connected to the inside of the connecting means.

[Claim 10]

The field-installable optical connector of claim 2, wherein the connecting means includes a connecting wing hinge-connected to both the top and the bottom of the clip portion or to at least one of them.

[Claim ll]

The field-installable optical connector of claim 2, wherein first and second guide pins are provided on the top of the first and second clip plates, and the connecting means includes guide holes having an oval shape provided in positions corresponding to the first and second guide pins.

[Claim 12]

The field-installable optical connector of claim 2, wherein a locking lever including a locking ring is rotatably provided on the top of at least one of the first and second clip plates, and a locking projection connected to the locking ring is provided on the top of the other clip plate. [Claim 13]

The field-installable optical connector of claim 2, wherein a plurality of projections is formed on the opposite surface of the clip portion and the connecting means such that a clamping force between the first and second clip plates is increased when the clip portion is connected by the connecting means.

[Claim 14] The field-installable optical connector of claim 1, wherein the main wire connecting member includes first and second plates, separately formed along the longitudinal direction that the main wire is inserted, the first plate includes first and second insertion grooves, the first insertion groove, connected to the ferrule holder and inserting the main wire, being connected to the second insertion groove for inserting the element wire, the first insertion groove having a V-shaped cross section, and the second plate includes a third insertion groove formed in a position corresponding to the second insertion groove.

[Claim 15]

The field-installable optical connector of claim 14, wherein a forth insertion groove for inserting a coated main wire is further included between the first and second insertion grooves, the forth insertion groove having a V- shaped cross section.

[Claim 16] The field-installable optical connector of claim 1, wherein at least two point projections are provided on the outer circumference of the main wire connecting member.

[Claim 17] The field-installable optical connector of claim 1, wherein the main wire connecting means has a taper shape and the connecting member insertion hole of the fixing member has a taper shape corresponding to the main wire connecting member .

[Claim 18]

The field-installable optical connector of claim 14, wherein at least one of the first and second plates is formed of a transparent material.

[Claim 19]

The field-installable optical connector of claim 14, wherein a C-shaped clip is connected to the front end of the main wire connecting member. [Claim 20]

The field-installable optical connector of claim 1, wherein a penetrating hole is provided on the housing and the fixing cap, respectively, in a position corresponding to the region where the main wire of the ferrule and the main wire of the optical cable are connected.