JP4119800B2 - Field assembly optical connector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a field assembly optical connector.
[0002]
[Prior art]
In the connection of optical fibers, a mechanical splice method is conventionally performed in which the end faces of two bare fibers are butted and the vicinity of the butted portion is pressed and fixed from the side of the bare fiber.
[0003]
In the conventional mechanical splice method, a fiber groove into which a bare fiber is inserted is formed in a positioning member, while a pressing member is disposed opposite to the positioning member, and a spring is provided so that the positioning member and the pressing member are in close contact with each other. The connection is made by a structure sandwiched between clamp members having force. A wedge insertion groove is formed in the boundary portion between the positioning member and the pressing member, and the wedge is inserted into the wedge insertion groove to increase the distance between the positioning member and the pressing member. A bare fiber is inserted into the groove from both sides, and the end face of the bare fiber is abutted at the middle part of the fiber groove. After that, by removing the wedge from the wedge insertion groove, the positioning member and the holding member are closed by the spring force of the clamp member, so the vicinity of the butt portion of the two optical fibers is pressed from the side by these members and connected. The state is fixed (see Patent Document 1).
[0004]
[Patent Document 1]
Japanese Unexamined Patent Publication No. 2000-121863 (second page, FIG. 3)
[0005]
[Problems to be solved by the invention]
However, in the conventional optical fiber connection, since the positioning member and the pressing member for pressing and fixing the optical fiber from the side face are in close contact with each other by the spring force of the clamp member, the wedge is inserted into the wedge insertion groove when the optical fiber is inserted. Need to be inserted and pushed open. For this reason, a wedge as a tool other than the constituent members is required, and not only the connection work is troublesome, but also the inconvenience that the connection work cannot be performed when the wedge cannot be prepared. Further, since the wedge is used, it takes time and labor to complete the assembly, and the workability is poor. Furthermore, it is necessary to process the wedge insertion groove separately, which is troublesome.
[0006]
The present invention has been made in view of such conventional problems, and does not require an external tool such as a wedge, enables assembly with only constituent members, and performs assembly in a simple and short time. It is an object of the present invention to provide an on-site assembly optical connector that can be used.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an on-site assembly optical connector according to a first aspect of the present invention includes a cylindrical frame having a sleeve extending in the axial direction therein, and a fiber hole having both ends opened in the axial direction. A first holding member inserted into the sleeve and abutted against the ferrule, a second holding member fitted to the rear end portion of the first holding member, and a second holding member fitted to the rear end portion of the second holding member. 3 holding members, and a fourth holding member into which the rear of the third holding member is inserted,
The second holding member has a front half portion in which a fitting hole is formed to be fitted to the first holding member from the outside, and a second half portion having a tapered surface in which the diameter of the outer surface gradually decreases from the front portion toward the rear portion. And the front half side has a small diameter, the latter half side has a large diameter and is penetrated in the axial direction, and is formed by a stepped fiber hole coaxially communicating with the fiber hole of the first holding member,
The third holding member is formed in a substantially cylindrical shape with a flange projecting on the outer periphery of the front portion, and is inserted into the rear end of the frame so as to be movable in the axial direction with the flange protruding outward.
On the other hand, a taper hole fitted from the outside to the taper surface of the second holding member is formed at the front end portion, and the taper communicates coaxially with the stepped fiber hole in a state where the diameter gradually increases from the front portion toward the rear portion. Fiber hole is formed at the rear end,
The fourth holding member is formed in a substantially cylindrical shape, with a spring accommodating portion between the front frame periphery is formed, receiving substantially central portion spring inwardly are projected, the spring A spring is housed between the front collar part and the rear spring receiver in the accommodating part , and the gap between the collar part and the front end of the fourth holding member is caused by the biasing force of the spring against the collar part. The fourth holding member is fitted into the outer periphery of the rear end of the frame while being moved and held so as to be formed.
[0008]
In the first aspect of the present invention, the second holding member, the third holding member, and the fourth holding member are assembled in this order with the first holding member inserted and attached to the frame, and the screw holes of the fourth holding member are attached to the frame. By screwing, the fiber hole of the first holding member, the stepped fiber hole of the second holding member, the tapered fiber hole of the third holding member, and the insertion hole of the fourth holding member are communicated in the axial direction. .
[0009]
At this time, a hook is projected from the front outer periphery of the third holding member, and the third holding member moves forward in the frame by the biasing force of the spring interposed between the hook and the spring receiver of the fourth holding member. Is retained. That is, the tapered surface behind the second holding member is pressed by the tapered hole provided in the center portion of the third holding member, and a gap is formed between the flange portion and the front end of the fourth holding member.
[0010]
In this state, when the collar portion is pushed and the third holding member is moved rearward, the collar portion contacts the rear end of the third retaining member and the spring is compressed. As a result, the pressing state against the second holding member by the tapered hole of the third holding member is released, so that the stepped fiber hole that has been squeezed by the pressing force expands to the original state.
[0011]
Therefore, the optical fiber is inserted from the rear end opening of the fourth holding member through the tapered fiber hole of the third holding member into the stepped fiber hole of the second holding member and further to the fiber hole of the first holding member.
[0012]
After the operation of inserting the optical fiber is completed in this way, if the pressing force against the collar portion of the third holding member is released, the pressing force by the third holding member against the second holding member works again, and the stepped fiber of the second holding member The hole squeezes. As a result, the optical fiber can be fixed so as not to be broken.
[0013]
Accordingly, the first holding member to the fourth holding member can be transported to the site in a state where they are completely assembled in the factory. And, since it is only necessary to insert an optical fiber at the site, the workability is good.
[0014]
Further, since the optical fiber can be connected without using a wedge, it is not necessary to use a tool other than the constituent members, and it is not necessary to process a wedge insertion groove for inserting the wedge. Further, since the optical fiber can be connected only by the constituent members, it is not necessary to use an external tool such as a wedge, and therefore, the assembly is simple and can be completed in a short time.
[0015]
Furthermore, since the pressing force of the fourth holding member is transmitted to the third holding member while interposing an elastic force, the core wire is always kept at a constant pressing force regardless of variations in the thickness of the core wire inserted into the fiber hole. The connector can be manufactured at a low cost with a reduced material cost without subjecting both holding members to precise processing.
[0016]
The invention according to claim 2 is characterized in that a pair of long grooves are formed at the rear end of the frame, and on the other hand, a pair of guide pieces that are slidably fitted into the long grooves inside the flange portion of the front portion of the third holding member, and A pair of arc-shaped holes into which both arc-shaped pieces of the frame are inserted are respectively formed.
[0017]
In the invention of claim 2, the third holding member does not rotate in the circumferential direction of the frame, but merely reciprocates linearly in the axial direction. Can be retreated. On the other hand, if the pressing force by the fingertip or the like is released, the frame can be smoothly advanced by the urging force of the spring.
[0018]
According to a third aspect of the present invention, a small-diameter portion is formed at the rear of the third holding member through a locking step portion provided at a substantially central portion, and on the other hand, a tubular slider is fitted into the small-diameter portion. In addition, an engagement protrusion that engages with the rear end of the slider is provided at the rear end of the screw hole of the fourth holding member.
[0019]
In the invention of claim 3, in a state where the urging force of the spring against the flange is working, there is a gap (equivalent to the gap between the flange and the fourth holding member) between the locking step of the third holding member and the slider. When the third holding member is held and retracted against the urging force of the spring, the locking step is formed so as to contact the front end of the slider.
[0020]
Therefore, the third holding member can smoothly swing in the slider and can be stopped at a predetermined retracted position. On the other hand, there is no possibility that the slider will come out of the rear end of the third holding member.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be specifically described with reference to embodiments shown in the drawings.
FIG. 1 is an exploded perspective view of a basic structure of an on-site assembly optical connector according to an embodiment of the present invention, FIG. 2 is a cross-sectional view after assembling, and FIG. 4 is a cross-sectional view after mounting the optical fiber, FIG. 5 is a plan view of the assembled optical connector, FIG. 6 is a cross-sectional view of the same, and FIG. 7 is a cross-sectional view before mounting the optical fiber. Respectively.
[0022]
The field assembly optical connector (hereinafter referred to as an optical connector) 1 of this embodiment is inserted into the counterpart ferrule 2 by being abutted against the counterpart ferrule 2 provided inside the split sleeve 10 as shown in FIG. The optical fiber 3 thus connected is connected. The optical connector 1 includes a frame 4 into which a tip portion of the mating ferrule 2 is inserted, a first holding member 5 that is inserted into the frame 4 so as to abut against the mating ferrule 2, and a rear end of the first holding member 5 A second holding member 6 that fits into the portion, a third holding member 7 that fits into the rear end of the second holding member 6, and a second screw that engages with the frame 4 with the third holding member 7 inserted. 4 holding member 8 and a third holding member 7 and a spring 9 interposed between the fourth holding member 8.
[0023]
The frame 4 includes a split sleeve 10 that covers a region including the abutting portion between the counterpart ferrule 2 and the first holding member 5 along the axial direction, and the first holding member 5 is in the split sleeve 10. By inserting, the 1st holding member 5 will be in the state which can be matched with the other party ferrule 2. FIG. Further, the frame 4 is formed with a screw portion 11 on the outer periphery of the rear portion thereof, to which the fourth holding member 8 is screwed. A pair of long grooves 12 are formed through the threaded portion 11 so as to open to the rear end, whereby the threaded portion 11 is separated into a pair of arcuate pieces 13 at opposing positions. In the figure, reference numeral 14 denotes an optical signal control filter inserted into the filter groove 2 a of the counterpart ferrule 2. The counterpart ferrule 2 and the first holding member 5 are formed of zirconia.
[0024]
The first holding member 5 is formed in a cylindrical shape whose outer surface is circular. In addition, a fiber hole 15 for inserting an optical fiber is formed along the axial direction in the central portion of the inside. The fiber hole 15 can be inserted into an optical fiber by opening both front and rear ends. The rear end portion of the first holding member 5 has come out of the split sleeve 10, and the second holding member 6 is fitted to this rear end portion.
[0025]
The second holding member 6 extends along the axial direction, and is formed by connecting a front half 6a and a rear half 6b in the axial direction. The front half portion 6a is fitted to the rear end portion of the first holding member 5 from the outside, and a fitting hole 16 therefor is formed in the axial direction. Further, the front end surface of the front half 6a can be brought into contact with a stopper surface 17 formed on the inner surface of the frame 4, and the axial movement of the second holding member 6 is stopped by contact with the stopper surface 17. It has become so. The rear half 6b of the second holding member 6 is a tapered surface 18 whose outer surface diameter gradually decreases from the front to the rear (to the right in FIG. 1). Then, the third holding member 7 is fitted.
[0026]
A stepped fiber hole 19 for inserting an optical fiber is formed in the second holding member 6 so as to penetrate the central portion in the axial direction. The stepped fiber hole 19 is formed so as to communicate with the fiber hole 15 of the first holding member in the axial direction. Further, the stepped fiber hole 19 has a large diameter on the rear half 6b side and a small diameter on the front half 6a side. When the optical fiber is inserted from the rear half 6b side, a core wire enters the small diameter section and enters the large diameter section. The optical fiber is fixed by tightening only the jacket that has entered.
[0027]
The third holding member 7 is formed in a cylindrical shape 7a extending along the axial direction, and inside the front end thereof, as shown in FIG. 1, the third holding member 7 is outside the tapered surface 18 of the rear half 6b of the second holding member 6. The taper hole 20 which fits from is formed. Further, a tapered fiber hole 21 is formed in the inner central portion so as to penetrate in the axial direction. The tapered fiber hole 21 communicates with the stepped fiber hole 19 of the second holding member 6, and the optical fiber can be inserted from the third holding member 7 side by this communication. The tapered fiber hole 21 has a structure in which the diameter gradually increases from the front part toward the rear part (toward the right direction). Thereby, it is possible to smoothly insert the optical fiber.
[0028]
On the other hand, on the outer periphery of the third holding member 7, a flange portion 22 is projected from the front portion of the substantially cylindrical shape 7 a, and a small diameter portion 24 is formed at a substantially central portion on the rear side via a locking step portion 23. Has been.
[0029]
The cylindrical portion 7a is formed with an outer diameter so as to be slidably fitted to the rear end of the frame 4. On the other hand, the flange portion 22 is sandwiched between the pair of long grooves 12 at the rear end of the frame 4 and the pair of arc-shaped holes 26 into which the pair of arc-shaped pieces 13 are inserted between the flange portion 22 and the cylindrical portion 7a. And an annular body 27 provided integrally on the outer periphery thereof.
[0030]
Further, a circular slider 28 is slidably fitted to the small diameter portion 24 at the rear end of the substantially cylindrical shape 7a. The slider 28 is formed so that its thickness substantially coincides with the height of the locking step portion 23, and its length is shorter than that of the small diameter portion 24.
[0031]
The fourth holding member 8 is formed in a cylindrical shape 8a extending along the axial direction, and an insertion hole 29 having a size into which the frame 4 and the third holding member 7 are inserted is formed at the center. The insertion hole 29 is formed with a step 30 in the substantially inner wall of the central portion, a housing portion 31 of the spring 9 that is externally mounted on the frame 4 is formed in the front half portion, and the screw portion 11 at the rear end of the frame 4 is formed in the rear half portion. A screw hole 32 to be screwed to a taper hole and a tapered hole 33 having a rear end greatly widened are successively formed. Reference numeral 8 b denotes a locking portion for preventing the slider 28 from coming off around the rear end of the insertion hole 29.
[0032]
1 to 4, reference numeral 34 denotes a stopper, which is inserted into a recess 6c provided on the outer periphery of the front half 6a of the second holding member 6 through the insertion hole 4a of the frame 4, and is inserted into the frame 4 of the holding member 6. Movement in the axial direction can be prevented.
[0033]
35 is a refractive index matching agent such as silicone oil applied to the rear end face of the counterpart ferrule 2, 36 is a large-diameter ferrule connected to the tip of the counterpart ferrule 2, and 37 is both ferrules 2 and 36. Each holder for holding
[0034]
5 to 7, reference numeral 38 denotes a connector housing to which the optical connector 1 is mounted. The connector housing 38 includes an outer knob 39 and a frame 40 inserted therein so as to be movable in the axial direction. 41 is a spring for urging the holder 36 forward in the frame 40, and 42 is a ring-shaped guide built in the rear end of the knob 39, and fixes the optical connector 1 at a predetermined position in the connector housing 38. It works as follows.
[0035]
Further, 43 indicates a boot extrapolated to the rear end of the fourth holding member 8, and 44 indicates a core wire (bare fiber) obtained by peeling off the outer cover (UV coating) of the optical fiber 45 and exposing it.
[0036]
Next, an optical fiber connection operation in this embodiment will be described.
Prior to the connection, the optical fiber core wire 3 is inserted into the central portion of the ferrules 2 and 36 and fixed with an adhesive. Further, both ends of the ferrules 2 and 36 are polished.
[0037]
Next, after applying a refractive index matching agent 35 such as silicon oil to the front end surface of the first holding member 5, the first holding member 5 is inserted into the split sleeve 10 to cover the member 5 with the frame 4. To do. Then, after fitting the fitting hole 16 of the second holding member 6 to the rear end of the first holding member 5, the tapered hole 20 is fitted to the tapered surface 18 of the second holding member 6, and the third holding member. 7 is assembled.
[0038]
At this time, the cylindrical portion 7 a in the third holding member 7 is inserted into the frame 4, while a pair of guide pieces 25 provided between the cylindrical portion 7 a and the flange portion 22 are provided on both sides of the rear end of the frame 4. The pair of arc-shaped holes 26 are inserted into the arc-shaped pieces 13 on both sides of the rear end of the frame 4, and the annular body 27 protrudes from the outer periphery of the frame 4.
[0039]
Next, after the slider 28 is fitted to the small diameter portion 24 at the rear end of the cylindrical portion 7 a in the third holding member 7, the spring 9 is extrapolated to the cylindrical portion 7 a at the rear end of the flange portion 22, and further the fourth holding member 8. Screw together.
[0040]
At this time, the spring 9 is housed in an annular spring housing portion 31 provided at the front end of the cylindrical portion 8 a of the fourth holding member 8, and the front end abuts against the flange portion 22, while the screw at the rear end of the frame 4 The rear end abuts on a step 30 provided substantially at the center of the cylindrical portion 8 a when the screw hole 32 is screwed into the portion 11.
[0041]
Accordingly, the flange portion 22 of the third holding member 7 is separated from the front end of the fourth holding member 8 by the biasing force of the spring 9. That is, the tapered hole 20 of the third holding member 7 is in pressure contact with the tapered surface 18 at the rear end of the second holding member 6, and the stepped fiber hole 19 is squeezed (state shown in FIG. 2).
[0042]
Note that, by assembling the first to fourth holding members 5 to 8, the fiber hole 15 of the first holding member 5, the stepped fiber hole 19 of the second holding member 6, and the tapered fiber hole of the third holding member 7. 21 and the rear end of the insertion hole 29 of the fourth holding member 8 are in coaxial communication with each other.
[0043]
Therefore, the flange portion 22 is retracted until it abuts against the front end of the fourth holding member 8 against the urging force of the spring 9 (state of FIG. 3). As a result, the pressing force by the tapered hole 20 of the third holding member 7 against the tapered surface 18 of the second holding member 6 is released, and the stepped fiber hole 19 expands, so that light is transmitted from the rear end of the insertion hole 29 of the fourth holding member 8. The core wire 44 at the tip of the fiber 45 is inserted. The core 44 is inserted through the tapered fiber hole 21 of the third holding member 7, the stepped fiber hole 19 of the second holding member 6, and the fiber hole 15 of the first holding member 5, and the mating ferrule 2. Is stopped by abutting against the optical fiber core wire 3.
In addition, the pressing operation with respect to the collar part 22 is performed manually. However, it can also be performed by inserting a tool in a gap l (see FIG. 5) provided between the connector housing 38 and the front end of the flange portion 22.
[0044]
After that, when the pressing force against the hook part is released, the hook part 22 is separated from the front end of the fourth holding member 8 by the urging force of the spring 9, whereby the third holding member 7 against the tapered surface 18 of the second holding member 6 again. The pressure contact force of the taper hole 20 acts to squeeze the stepped fiber hole 19 and press and hold the core wire 44 (state of FIG. 4).
[0045]
By the way, the optical connector 1 is assembled at the factory, and only the assembly to the connector housing 38 and the assembly of the optical fiber core wire 44 and the boot 43 are performed at the site.
[0046]
In this embodiment, application to an optical connector having a termination function is shown. However, the present invention can be applied to optical connectors having other structures.
[0047]
【The invention's effect】
According to the on-site assembly optical connector of the present invention, the first holding member, the second holding member, the third holding member, and the fourth holding member are not temporarily assembled, but are assembled at the factory. Since the connection of the optical fiber core wire can be performed easily and reliably by only one-touch pressing operation, workability is extremely good.
[0048]
In addition, it is not necessary to use a wedge as an external tool, and it is not necessary to process a wedge insertion groove for inserting a wedge, so that the assembly is easy and can be completed in a short time, which is suitable for on-site assembly. Can be used.
[0049]
Further, since the pressing force of the fourth holding member is transmitted to the third holding member while interposing an elastic force, the core wire is always kept at a constant pressing force regardless of variations in the thickness of the core wire inserted into the fiber hole. Can be held.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a basic structure in an on-site assembly optical connector of the present invention.
FIG. 2 is a cross-sectional view after assembling.
FIG. 3 is a cross-sectional view showing a pre-process for attaching the optical fiber according to the first embodiment.
FIG. 4 is a cross-sectional view after attaching the optical fiber.
FIG. 5 is a plan view of the entire optical connector in an assembled state.
FIG. 6 is a cross-sectional view of the above.
FIG. 7 is a cross-sectional view before attaching an optical fiber.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Field assembly optical connector 2 Opposite side ferrule 3 Optical fiber core wire 4 Frame 5 1st holding member 6 2nd holding member 7 3rd holding member 8 4th holding member 9 Spring 11 Screw part 12 Long groove 13 Arc-like piece 15 Fiber hole 16 Fitting hole 17 Stopper surface 18 Tapered surface 19 Stepped fiber hole 20 Tapered hole 21 Tapered fiber hole 22 Gutter part 23 Locking step part 24 Small diameter part 25 Guide piece 26 Arc-shaped hole 27 Annular body 28 Slider 29 Insertion hole 30 Step 31 Spring storage part 32 Screw hole 44 Core wire

Claims (3)

A tubular frame in which an axially extending sleeve is provided; a first holding member that is formed in the axial direction with a fiber hole that is open at both ends, and that is inserted into the sleeve and abuts against the ferrule; A second holding member fitted to the rear end of the first holding member; a third holding member fitted to the rear end of the second holding member; and a fourth holding member into which the rear of the third holding member is inserted. And
The second holding member has a front half portion in which a fitting hole is formed to be fitted to the first holding member from the outside, and a second half portion having a tapered surface in which the diameter of the outer surface gradually decreases from the front portion toward the rear portion. And the front half side has a small diameter, the latter half side has a large diameter and is penetrated in the axial direction, and is formed by a stepped fiber hole coaxially communicating with the fiber hole of the first holding member,
The third holding member is formed in a substantially cylindrical shape with a flange projecting on the outer periphery of the front portion, and is inserted into the rear end of the frame so as to be movable in the axial direction with the flange protruding outward.
On the other hand, a taper hole that is fitted to the taper surface of the second holding member from the outside is formed at the front end, and the taper is coaxially communicated with the stepped fiber hole in a state where the diameter gradually increases from the front to the rear. Fiber hole is formed at the rear end,
The fourth holding member is formed in an approximately cylindrical shape, with a spring accommodating portion between the front frame periphery is formed, receiving substantially central portion spring inwardly are projected, the spring A spring is housed between the front collar in the housing and the rear spring receiver, and the third holding member is urged by the biasing force of the spring against the collar, and there is a gap between the collar and the front end of the fourth retaining member. A field assembly optical connector characterized in that it is moved and held so as to be formed, and the fourth holding member is fitted into the outer periphery of the rear end of the frame. A pair of long grooves are formed at the rear end of the frame. On the other hand, a pair of guide pieces that are slidably fitted into the long grooves are inserted inside the flange portion of the front portion of the third holding member, and both arc-shaped pieces of the frame are provided. 2. The field assembly optical connector according to claim 1, wherein a pair of arcuate holes to be inserted are formed. A small-diameter portion is formed at the rear of the third holding member via a locking step provided at a substantially central portion. On the other hand, a tubular slider is fitted to the small-diameter portion, and the first 2. The field assembly optical connector according to claim 1, wherein an engagement projection for engaging with the rear end of the slider is provided at the rear end of the screw hole of the four holding member.

Images