JP4387732B2 - Optical connector - Google Patents

Description

  The present invention relates to an optical connector used for connecting an optical fiber, and in particular, can be connected to an optical fiber in the field or the like, and the optical fiber connected to the optical connector is also stored in a narrow place such as an outlet box. It relates to an optical connector.

As a technology for wiring optical fibers in buildings such as buildings and houses, an outlet for enabling optical fibers wired to walls and the like to be connected to optical fibers connected to indoor devices, etc. Various proposals have been made.
For example, Patent Document 1 describes an optical connector outlet in which an optical connector for connecting an optical fiber is provided on a front panel of a box.
In Patent Document 2, an optical connector provided on a cover (front plate) on the front surface of a box (box) and a mechanical connector housed in the box are connected in advance by an optical waveguide (optical fiber). An optical connector is described in which an optical fiber such as an optical fiber cable is connected to the optical waveguide via the mechanical connector.
JP 2001-141956 A JP-A-6-171978

However, in the case of the optical connector outlet described in Patent Document 1, in order to connect the wall-side optical fiber to the optical connector at the wiring site, the optical fiber is inserted and connected to the optical connector, and then the joint end surface of the optical connector is connected. Work such as polishing and various tools such as a polishing machine are required, which takes time and effort. Moreover, when the extra length of the optical fiber that can be pulled out from the wall is short, it may be difficult to apply the optical connector attached to the optical fiber to a tool such as a polishing machine.
In the case of the optical connector described in Patent Document 2, the two optical fibers connected by the mechanical connector are accommodated in the box without any restriction, so that the optical characteristics of the optical fiber are adversely affected. Such bending deformation may be applied to the optical fiber. For example, the optical fiber may be damaged when the cover is attached or detached.

  The present invention has been made in view of the above circumstances, is easy to assemble, can be attached to a narrow place such as an outlet box, and can suppress bending deformation exceeding an allowable limit to an optical fiber. It is an object to provide an optical connector.

In order to solve the above-mentioned problem, the present invention provides a portion protruding from the rear end of the ferrule of the connection optical fiber and another optical fiber at the rear end facing the joining end surface of the ferrule in which the connection optical fiber is preliminarily installed. A clamp portion for clamping and holding the butt connection state is provided, and the housing for housing the ferrule and the clamp portion is for inserting and housing the optical connector to be connected so as to be opposed to the joining end surface of the ferrule. The optical connector housing hole, and the housing includes a clamp portion housing portion for housing the clamp portion and a housing lid fitted to the clamp portion housing portion, and the housing lid on the rear end side of the housing. the rear end wall, the other has an optical fiber is an optical fiber insertion hole for inserting formed on the clamp portion, The peripheral portion of the optical fiber insertion hole, said there are other curved surface for light characteristics to ensure allowable bending radius than the bend radius such as to maintain the optical fiber, the rear end of the clamping portion, the A taper hole for inserting another optical fiber into the clamp portion is opened, and the curved surface has a maximum width at the rear end of the housing, and the maximum width is the rear end of the clamp portion. In a state where the diameter is reduced from the rear end of the housing toward the tapered hole at the rear end of the clamp portion , and the housing lid is integrated with the clamp portion storage portion. An optical connector is provided, wherein a curved surface is connected to a tapered hole at a rear end of the clamp portion .
In this optical connector, the clamp portion includes a pair of elements that sandwich the optical fibers, and the ferrule is harder than the integral member, and a ferrule base formed as a member integral with any of the elements. It is also possible to adopt a configuration comprising a ferrule tip member made of the above material and joined to the ferrule base.
Further, there is a configuration in which an opening member for ensuring the open state of the clamp portion is interposed in the clamp portion, and the clamping force to the optical fiber by the clamp portion acts by removing the release member. It can be adopted.
The optical connector of the present invention is suitable for an outlet box.

According to the optical connector of the present invention, since the clamp part for connecting the optical fiber is provided at the rear end of the ferrule, the connection optical fiber built in the ferrule is exposed to the outside of the ferrule and the clamp part. Therefore, the optical fiber for connection is accommodated in the ferrule and the clamp part, and there is no possibility that bending deformation exceeding the allowable limit is applied to the connecting optical fiber. Even at the site of wiring work, it is easy to assemble the optical connector at the tip of the optical fiber, and since the polishing of the ferrule is unnecessary, workability can be greatly improved.
Furthermore, by providing a curved surface at the peripheral edge of the optical fiber insertion hole formed on the rear end side of the housing, bending beyond the allowable limit can be applied to other optical fibers connected to the connecting optical fiber at the clamp portion. It is possible to suppress the deformation. In addition, since the opening amount on the rear end side of the optical fiber insertion hole can be increased, the optical fiber can be easily inserted into the clamp portion.
Therefore, even when the optical connector of the present invention is attached to a narrow place such as an outlet box, the connection characteristic of the optical fiber can be secured to a level sufficient for optical transmission.

The best mode for carrying out the present invention will be described below with reference to the drawings.
FIG. 1 is a front sectional view showing an optical connector of the present invention. FIG. 2 is a cross-sectional plan view showing the optical connector of FIG. FIG. 3 is a left side view showing the optical connector of FIG.
4 and 5 are views showing a ferrule with a clamp portion in the optical connector of FIG. 1, FIG. 4 is a front view sectional view, and FIG. 5 is a plan view sectional view. 6 is a drawing showing a housing body in the optical connector of FIG. 1, wherein (a) is a plan view, (b) is a front view, (c) is a left side view, and (d) is a right side view. 7 is a drawing showing a housing lid in the optical connector of FIG. 1, wherein (a) is a plan view, (b) is a front view, (c) is a left side view, and (d) is a right side view. FIG. 8 is an exploded perspective view of the optical connector of FIG.
FIG. 9 is a perspective view showing a state in which the optical connector and the opening member of FIG. 1 are opposed to each other. FIG. 10 is a cross-sectional view showing a state in which the wedge portion of the opening member attached to the optical connector of FIG. 1 is inserted into the clamp portion of the optical connector. 11 is a cross-sectional view showing a state in which the wedge portion of the opening member attached to the optical connector of FIG. 1 is detached from the clamp portion of the optical connector. 12 is a cross-sectional view showing a state in which another optical fiber is brought closer from the rear end side of the optical connector of FIG. 13 is a cross-sectional view showing a state in which another optical fiber is inserted from the rear end side of the optical connector of FIG. FIG. 14 is a cross-sectional view showing a state in which the connecting optical fiber and another optical fiber are connected in the clamp portion of the optical connector of FIG. 15 is a cross-sectional view showing a state where an optical connector plug is inserted and connected to the optical connector of FIG. FIG. 16 is a cross-sectional view showing a state in which an optical connector plug is disposed opposite to the optical connector of FIG.

As shown in FIG. 1, FIG. 15, FIG. 16, etc., the optical connector 1 includes a ferrule 3 in which a connecting optical fiber 34 is preliminarily built, a portion protruding from the rear end of the ferrule 3 of the connecting optical fiber 34, and the like. The clamp portion 4 for clamping and holding the butt connection state with the optical fiber 48 and the housing 2 for housing the ferrule 3 and the clamp portion 4 are provided.
As shown in FIGS. 4 and 5, the clamp portion 4 is connected to the ferrule 3 so as to extend from the rear end facing the joining end surface 32 of the ferrule 3. Thereby, the ferrule 30 with a clamp part in which the ferrule 3 and the clamp part 4 are integrated is configured.
As shown in FIGS. 15 and 16, the optical connector housing hole 11 for inserting and housing the optical connector 6 (optical connector plug) that is disposed to be opposed to and connected to the joining end face 32 of the ferrule 3 is provided. Functions as a connector receptacle.
Here, the optical connector plug 6 is an SC type optical connector plug (SC: Single fiber Coupling) defined in JIS C 5973 and the like, and as shown in FIGS. The ferrule 61 that fixes and holds the bare optical fiber (not shown) that has been removed and is held in the housing 63, and the optical fiber 64 exposed on the rear end side of the housing 63 is accommodated in the housing 63. It is configured to be protected by an elastomer (rubber or the like) boot 65 attached to the rear end.

As shown in FIGS. 1, 2, 4, and 5, the ferrule 3 includes a ferrule tip member 31 having a fine hole 33 therein, and an end portion 35 on the side opposite to the joining end surface 32 of the ferrule tip member 31. And a ferrule base 36 joined to each other.
The ferrule tip member 31 is made of a hard material such as ceramics such as zirconia or glass, and is formed in a substantially cylindrical shape. The outer peripheral surface 31a of the ferrule tip member 31 is a cylindrical surface. As the material of the ferrule tip member 31, a material harder than the material of the integral member 37 including the ferrule base portion 36 is used.
The central axis of the fine hole 33 is precisely positioned with respect to the outer peripheral surface 31 a of the ferrule tip member 31. Thus, as is well known, when the joining end faces 32 and 62 of the ferrules 3 and 61 of the two optical connectors 1 and 6 are opposed to each other and the end faces of the optical fibers 34 and 64 are butted, both ferrules are used. By attaching the split sleeve 14 to 3, 61, the optical fibers 34, 64 can be precisely aligned and optically connected.
The joining end face 32 of the ferrule tip member 31 may be polished after the connection optical fiber 34 is inserted into the fine hole 33. The connection optical fiber 34 includes a portion 34 a that is built in the ferrule 3 and a portion 34 b that protrudes from the rear end of the ferrule 3.

  The ferrule base portion 36 is a portion interposed between the ferrule tip member 31 and the clamp portion 4, and an outer peripheral surface 36 a thereof is substantially cylindrical. The diameter (outer diameter) of the ferrule base 36 is slightly smaller than the diameter (outer diameter) of the ferrule tip member 31. That is, the outer peripheral shape of the ferrule base 36 is smaller than the outer peripheral shape of the ferrule tip member 31. For this reason, even if the dimensional accuracy of the ferrule base 36 is somewhat low, the outer peripheral surface 36a is prevented from protruding from the outer peripheral surface 31a of the ferrule tip member 31, and when the split sleeve 14 is attached to the ferrule tip member 31 The outer peripheral surface 36a of the ferrule base 36 is prevented from interfering with the split sleeve 14. Therefore, alignment of the optical fibers 34 and 64 can be performed with high accuracy.

The end portion 35 of the ferrule tip member 31 is an extending portion whose outer peripheral shape is smaller than the outer peripheral shape of the ferrule tip member 31 (hereinafter, the end portion 35 may be referred to as the extending portion 35). The ferrule tip member 31 and the ferrule base 36 are joined so that the outer peripheral surface 35 a of the extension 35 is covered by a part of the ferrule base 36 and the extension 35 is embedded in the ferrule base 36. .
An annular groove 35 b is formed on the outer peripheral surface 35 a of the extending portion 35 along the periphery of the extending portion 35. As described above, since the outer peripheral surface 35a has irregularities such as the groove 35b, the resin forming the ferrule base 36 is solidified into irregularities, and the bonding strength is high.

As shown in FIGS. 4, 5, and 8, the clamp portion 4 is attached to the elements 41, 42, 43 having a split structure and the outside of these elements 41, 42, 43, and clamps them by sandwiching them. A U-shaped spring member 46 is provided. Here, the elements 41, 42, 43 are composed of a base body 41 and lid bodies 42, 43 that are arranged side by side facing the base body 41, and are integrated into a prismatic shape by the clamping force of the spring member 46. It has become.
The elements 41, 42, and 43 may be cylindrical (each element divided in half is semicircular in cross section). In this case, the spring member 46 may be C-shaped.

  The base body 41 and the ferrule base portion 36 are integrally formed of a synthetic resin to form an integral member 37. Hereinafter, the integral member 37 may be referred to as a main member resin molding portion 37, and the ferrule base member 36 of the main member resin molding portion 37 may be referred to as a main member 38. The ferrule 30 with a clamp portion is assembled by combining the main body member 38 with the lid bodies 42 and 43 and clamping the base body 41 and the lid bodies 42 and 43 with the spring member 46. As described above, in the optical connector 1 according to this embodiment, the main member 38 is integrally formed, so that the base body 41 is always stably supported at a fixed position with respect to the ferrule 3. Therefore, the stability of the connection (see FIG. 14) between the optical fibers 34 and 48 in the clamp portion 4 is improved.

A positioning groove 44 that positions and aligns the optical fibers 34 and 48 is provided in the longitudinal direction of the base 41 as a centering mechanism on the mating surfaces 41a and 42a where the base 41 and the lid 42 on the front end side are overlapped. It is formed to extend. Here, the positioning groove 44 is formed on the mating surface 41a of the base body 41. However, the present invention is not limited to this, and the configuration in which the positioning groove 44 is formed on the mating surface 42a on the lid body 42 side, or the base body 41 and the lid body. A configuration formed on both sides of 42 can also be adopted. The cross-sectional shape of the positioning groove 44 is, for example, a V groove, but may be a U groove, a round groove (a groove having a semicircular cross section), or the like. The positioning groove 44 is provided for each pair of optical fibers 34 and 48 to be connected (for the number of cores). The optical fiber 48 is a connector that is optically connected to a connecting optical fiber 34 (specifically, a portion 34 b protruding from the rear end of the ferrule 3 of the connecting optical fiber 34) housed in the ferrule 3. An optical fiber, here, a bare optical fiber exposed by removing the coating on the tip side of a single-core optical fiber (optical fiber).
In the present invention, the other optical fiber 48 that is optically connected to the connecting optical fiber 34 and terminated by the optical connector 1 is an optical fiber, a multi-fiber, depending on the configuration of the ferrule 3 or the like. Various single-core or multi-core optical fibers such as an optical fiber ribbon can be used.

A taper hole 45 b for inserting the optical fiber 48 into the clamp part 4 is opened at the rear end of the clamp part 4. The tapered hole 45b is formed in a funnel shape on the mating surfaces 41a and 43a of the base body 41 and the lid 43 on the rear end side.
Between the positioning groove 44 and the tapered hole 45b, a covering housing groove 45a communicating with the positioning groove 44 and the tapered hole 45b is provided. The covering housing groove 45a is formed at a position where the mating surfaces 41a and 43a where the base body 41 and the lid 43 on the rear end side are overlapped face each other. The sheath receiving groove 45a accommodates the tip end portion of the sheath portion 48b of the optical fiber 48, and when the elements 41 and 43 are clamped by the spring member 46, the sheath portion 48b of the optical fiber 48 can be firmly clamped. It has a shape.

  Further, a wedge insertion groove 47 for inserting a wedge 51 (details will be described later) of the opening member 5 is formed on one side edge portion of the mating surfaces 41a, 42a, 43a on which the base body 41 and the lid bodies 42, 43 are overlapped. ing. As shown in FIG. 10 and the like, the clamp portion 4 can push open the base body 41 and the lid bodies 42 and 43 against the clamping force of the spring member 46 by press-fitting the wedge 51 into the wedge insertion groove 47. It can be done. When the wedge 51 is removed from the wedge insertion groove 47, the space between the base body 41 and the lid bodies 42 and 43 can be closed, and the state can be brought into an integrated state again by the clamping force of the spring member 46.

As shown in FIGS. 1, 2, 8, and the like, the housing 2 includes a plug insertion portion 10, a housing main body 15 fixed to the rear end side of the plug insertion portion 10, and a rear end portion of the housing main body 15. 17 and a housing lid 20 that is detachably fitted to and integrated with the housing lid 20.
As shown in FIGS. 1 and 2, the plug insertion portion 10 has an optical connector accommodation hole 11 opened on the distal end side (left side in FIGS. 1 and 2). In this optical connector housing hole 11, an optical connector 6 (optical connector plug) that is disposed so as to be opposed to and connected to the joining end surface 32 of the ferrule 3 can be detachably accommodated (see FIG. 16). In the optical connector housing hole 11, a pair of elastic engagement pieces 12 facing each other are provided so as to project from the back side of the optical connector housing hole 11 toward the opening 11 a. Engaging protrusions 12 a for engaging with engaging recesses 63 a formed on both sides of the housing 63 of the optical connector plug 6 are provided at the protruding tips of the respective elastic engaging pieces 12. A sleeve holder 13 having a ferrule accommodation hole 13a for accommodating the ferrule 61 of the optical connector plug 6 is provided between the elastic engagement pieces 12 so as to protrude from the opening 11a.

As shown in FIGS. 1, 2, and 6, the housing main body 15 includes a base portion 16 having a ferrule housing hole 16 a and a square cylindrical clamp portion housing portion 17 protruding toward the rear end side of the base portion 16. The housing body 15 and the plug insertion portion 10 are joined with an adhesive or the like so that the ferrule accommodation holes 13a and 16a are communicated with each other. In a state where the plug insertion portion 10 and the housing body 15 are joined, the ferrule accommodation holes 13a and 16a are connected so that the optical connector accommodation hole 11 of the plug insertion portion 10 communicates with the internal space 17c of the clamp portion accommodation portion 17. The space between the sleeve holder 13 and the base 16 is penetrated.
A split sleeve 14 having a C-shaped cross section is mounted in the ferrule receiving holes 13a and 16a so as to straddle the plug insertion portion 10 and the housing main body 15.
The ferrule 3 of the optical connector 1 and the ferrule 61 of the optical connector plug 6 are inserted into the split sleeve 14 with the joining end faces 32 and 62 facing each other. The split sleeve 14 guides the outer peripheral surfaces 31a and 61a of the ferrules 3 and 61 in order to precisely align the optical fibers 48 and 64 housed in the ferrules 3 and 61, respectively.

The plug insertion portion 10 inserts the front end portion of the optical connector plug 6 into the optical connector receiving hole 11, the engagement protrusions 12 a at the tip of the elastic engagement piece 12, and engagement recesses 63 a on both sides of the housing 63 of the optical connector plug 6. And the ferrule 61 of the optical connector plug 6 is inserted into the ferrule housing hole 13a so as to face the ferrule 3 of the optical connector 1 in the split sleeve 14, whereby the connecting optical fiber 34 is connected to the optical fiber 64. And optical connection.
The optical connector plug 6 inserted and connected to the optical connector receiving hole 11 of the optical connector 1 is a housing 63 (more specifically, a knob mounted on the outside of the plug frame having the engaging recess 63a in the housing 63. Part) is pulled toward the rear end 63b with a finger or a tool to release the engagement between the engagement recess 63a of the housing 63 and the engagement protrusion 12a of the optical connector 1 and remove it from the optical connector accommodation hole 11 Can be done.

The clamp part storage part 17 has an internal space 17c in which the clamp part 4 is stored. The internal space 17c opens to the rear end side that is the opposite side of the base 16 (opening 17d). The housing body 15 is configured such that the ferrule 3 can be accommodated in the ferrule accommodation hole 16 a and the clamp portion 4 can be accommodated in the clamp portion accommodation portion 17 by inserting the ferrule 30 with a clamp portion from the opening 17 d.
On the two side surfaces of the clamp portion storage portion 17 facing each other, an elastic engagement piece 18 having a locking claw 18a at the tip is formed on each of the side surfaces. The locking claw 18 a protrudes outward from the clamp portion storage portion 17, and the elastic engagement piece 18 is elastic so that the locking claw 18 a moves backward toward the internal space 17 c of the clamp portion storage portion 17. Can be curvedly deformed.
Further, wedge insertion ports 17 a and 17 b for inserting the wedge 51 toward the clamp portion 4 are formed on the other side surface of the clamp portion storage portion 17 different from the surface having the elastic engagement piece 18.
In the internal space 17c of the clamp part storage part 17, elements 41, 42, and so on by inserting a wedge 51 between the clamp part 4 (specifically, between the clamp part 4 and the back surface of the elastic engagement piece 18). A clearance necessary for opening and closing 43 is secured.

  The housing lid 20 is provided at a rectangular tube-shaped exterior part 21 fitted to the outer surface of the clamp part storage part 17 and a rear end of the exterior part 21, and has an opening 17 d in the internal space 17 c of the clamp part storage part 17. And a rear end wall 22 for covering. The exterior portion 21 includes a window portion 21 a formed in a cutout shape corresponding to the wedge insertion ports 17 a and 17 b of the clamp portion storage portion 17, and a pair of elastic engagement pieces 18 and 18 of the clamp portion storage portion 17. It has a pair of engagement holes 21b and 21b formed corresponding to the position of the locking claw 18a. Further, the rear end wall 22 has an optical fiber insertion hole 23 that extends in a tapered shape toward the rear end 24 of the housing lid 20 at the center. Specifically, the peripheral edge of the optical fiber insertion hole 23 includes the front-rear direction of the housing 2 (the direction in which the ferrule housing holes 13a and 16a extend, as shown in FIGS. 1 and 2). In the cross section, the curved surface 23a is curved in an arc shape. The curved surface 23 a is reduced in diameter from the rear end 24 of the housing lid 20 toward the tapered hole 45 b of the clamp portion 4. The curvature radius of the curve of the cut surface (see FIGS. 1 and 2) in the cross section including the front-rear direction of the housing 2 of the curved surface 23a is larger than the allowable bending radius that can maintain the optical characteristics (such as bending loss) of the optical fiber 48. It is preferable to do.

When the housing lid 20 is attached to the outside of the clamp portion storage portion 17, the locking claw 18 a of the elastic engagement piece 18 of the clamp portion storage portion 17 engages with the engagement hole 21 b of the housing lid 20, and the housing main body 15. The housing lid 20 is integrated. In a state in which the housing main body 15 and the housing lid 20 are integrated, the wedge insertion ports 17 a and 17 b of the clamp portion storage portion 17 are exposed to the outside through the window portion 21 a of the housing lid 20. The clamp part 4 is accommodated in the clamp part accommodating part 17 so that the direction of the wedge insertion groove 47 matches the positions of the wedge insertion ports 17a and 17b and the window part 21a.
Further, in this housing 2, the locking claw 18 a of the elastic engagement piece 18 is pushed into the inner space 17 c side of the clamp portion storage portion 17 and is released from the engagement hole 21 b, thereby removing the housing lid 20 from the housing body 15. It is possible.

As shown in FIGS. 9 to 11, the opening member 5 includes five plate-like movable pieces 52 a, 52 a, 52 b, 52 b, 52 c connected in a ring shape via elastic hinges 53 b, 53 b, 53 c, 53 c. The wedge drive unit 52, the holder unit 54 connected to both ends of the wedge drive unit 52 via elastic hinges 53a and 53a and assembled to the outside of the housing 2 of the optical connector 1, and the wedge drive unit 52 A wedge 51 protruding toward the holder portion 54 from a movable piece 52c located at the end opposite to the holder portion 54 (hereinafter, sometimes referred to as the movable piece 52c). Have.
Here, the opening member 5 can be manufactured as a synthetic resin-based integrally molded product. However, in the present invention, the opening member 5 is not particularly limited thereto, and may be composed of a plurality of parts.

  As shown in FIGS. 9, 12, etc., the wedge 51 has two tip portions 51 a, 51 b corresponding to the two lid bodies 42, 43 of the clamp portion 4. The respective front end portions 51a and 51b of the wedge 51 can be inserted into the wedge insertion groove 47 of the clamp portion 4 through the wedge insertion ports 17a and 17b.

  The holder portion 54 includes a bottom wall 54b protruding from each end portion 53a of the wedge drive portion 52 toward the other end portion 53a, and a side wall 54a projecting perpendicularly from the end portion 53a to the bottom wall 54b. Each of the side walls 54a has a bent end portion 54c that is bent in an L shape from the tip of the side wall 54a toward the other side wall 54a, and is configured in a U-shaped cross section. Between both side walls 54a, there is an accommodation recess 55 in which the housing 2 is removably accommodated. The holder portion 54 holds the housing 2 disposed in the housing recess 55 between the opposite side walls 54a, and engages the bottom wall 54b and the bent end portion 54c with both side surfaces of the housing 2, thereby 2 can be held.

The opening member 5 assembles the housing 2 to the holder portion 54 and presses the movable end portion 52 c toward the clamp portion 4 in the housing 2, so that the tip portions 51 a and 51 b of the wedge 51 are connected to the element 41 of the clamp portion 4. , 42, 43 can be inserted.
As shown in FIG. 10, when the tip 51a of the wedge 51 is inserted into the wedge insertion groove 47 from the wedge insertion port 17a, the space between the mating surfaces 41a and 42a of the base body 41 and the lid 42 is opened, and the positioning groove 44 is irradiated with light. A gap is created so that the fiber 48 can be inserted. Although not shown in FIG. 10, the tip 51b of the wedge 51 is inserted into the wedge insertion groove 47 from the wedge insertion port 17b at the same time and in the same manner as the tip 51a. The space between the mating surfaces 41a and 43a is also opened.
Further, as shown in FIG. 11, by pressing the wedge drive unit 52 from both sides (the side of the elastic hinges 53b and 53b), the movable end 52c is deformed so as to move away from the holder unit 54, and the wedge 51 The tip portions 51a and 51b are extracted from between the elements 41, 42 and 43.
As shown in FIG. 10, the optical connector 1 according to this embodiment can be sold, carried, etc. with the housing 2 attached to the holder portion 54 of the opening member 5.

Next, an example of how to use the optical connector 1 will be described.
As shown in FIGS. 10 and 12, the front end portions 51 a and 51 b of the wedge 51 are inserted into the wedge insertion groove 47 of the clamp portion 4, and the optical fiber insertion hole 23 at the rear end of the optical connector 1 is barely connected to the front end. The optical fiber 48 with the optical fiber 48 a exposed is inserted between the elements 41, 42 and 43. At this time, since the peripheral edge portion of the optical fiber insertion hole 23 is a curved surface 23a whose diameter is reduced toward the tapered hole 45b of the clamp portion 4, the distal end of the optical fiber 48 is tapered by the curved surface 23a. The optical fiber 48 can be easily inserted.
When the optical fiber 48 is inserted into the clamp portion 4, the end surface of the bare optical fiber 48 a is abutted against the end surface of the connection optical fiber 34 b in the clamp portion 4 in the positioning groove 44 as shown in FIG. 13. At this time, since the optical fiber 48 bends (bent portion 48t) in the vicinity of the curved surface 23a of the optical fiber insertion hole 23, the contact force between the end faces of the optical fibers 34 and 48 is secured by the elasticity of the optical fiber 48 itself. be able to.
After confirming the bent portion 48t of the optical fiber 48 as described above, the wedge of the opening member 5 is removed from the clamp portion 4 as shown in FIGS. Then, the optical fibers 34 and 48 are clamped and held between the elements 41, 42, and 43 by the clamping force of the clamp portion 4 (specifically, the spring member 46), with the end faces butting each other. The optical connection is maintained. As indicated by a two-dot chain line in FIG. 14, even if a side pressure such as a side pull (lateral pull) is applied to a portion of the optical fiber 48 protruding from the rear end of the housing 2, the optical fiber 48 follows the curved surface 23a. As a result, the bending radius of the optical fiber 48 can be avoided to be smaller than the curvature radius of the curved surface 23a, and the optical characteristics of the optical fiber 48 can be easily maintained at a sufficient level.

As described above, according to the optical connector of the present embodiment, the clamp portion 4 for connecting the optical fibers 34 and 48 is connected to the ferrule 3 so as to extend from the rear end of the ferrule 3. Since the ferrule 30 with the clamp portion is configured, the connecting optical fiber 34 built in the ferrule 3 is accommodated in the ferrule 30 with the clamp portion without being exposed to the outside of the ferrule 30 with the clamp portion. Therefore, there is no possibility that bending deformation exceeding the allowable limit is applied to the connection optical fiber 34.
Further, since the curved surface 23 a is provided at the peripheral edge of the optical fiber insertion hole 23 formed on the rear end 24 side of the housing 2, another optical fiber connected to the connection optical fiber 34 at the clamp portion 4. Also about 48, it can suppress that the bending deformation exceeding an allowable limit is added. Accordingly, since the rubber boot for protecting the optical fiber 48 can be omitted, the number of parts can be reduced.
Since the housing 2 has the optical connector housing hole 11 into which the optical connector plug 6 is inserted, the push spring that presses the ferrule 3 in the direction of the ferrule 61 of the optical connector plug 6 can be omitted. For this reason, the number of parts can be further reduced.
The length of the optical connector can be shortened, and the optical connector can be attached to a narrow place such as an outlet box or an outdoor termination box. In addition, in this case, the connection characteristics of the optical fiber can be ensured to a degree sufficient for optical transmission.
Since the opening amount of the optical fiber insertion hole 23 is large, it is easy to insert the optical fiber 48 into the housing 2.

The base 41 of the clamp part 4 is formed as a main member resin molding part 37 integral with the ferrule base part 36, and the tip part of the ferrule 3 is a ferrule tip member 31 made of a material harder than the main member resin molding part 37. Since it is comprised, hard materials, such as a ceramic, can be used only for the front-end | tip part of the ferrule 3, and cost can be reduced. Since the main member resin molding portion 37 is molded so as to embed the extended portion 35 of the ferrule tip member 31 in the ferrule base portion 36, the reliability of joining with the ferrule tip member 31 is improved. Since the hard ferrule tip member 31 is secured, the positional accuracy of the fine holes 33 can be ensured with high accuracy, and the optical fibers housed in the ferrule can be reliably aligned by the split sleeve 14.
Further, since the bending force applied to the distal end portion of the ferrule 3 is received and alleviated by the entire hard ferrule distal end member 31 and the resin ferrule base portion 36, the ferrule distal end member 31, the main member resin molding portion 37, and The joint strength is improved. Moreover, durability with respect to the bending of the ferrule 30 with a clamp part can be improved.

If the wedge 51 of the opening member 5 is preliminarily inserted into the wedge insertion groove 47 of the clamp portion 4, the trouble of inserting the wedge 51 into the wedge insertion groove 47 during assembly work can be omitted. Since the opening member 5 can be operated to insert and remove the wedge 51 only by manually pressing the wedge driving unit 52, the operation of assembling the optical connector 1 at the tip of the optical fiber 48 becomes very simple. Since a dedicated tool for assembly is not required, particularly in the field where optical fibers are wired, it is extremely advantageous in terms of efficiency of wiring work and cost reduction.
By integrally molding the opening member 5 with resin, it can be manufactured at a low cost, and a significant cost reduction can be realized as compared with the case of using a dedicated tool.

The present invention is not limited to the best mode described above, and various modifications can be made without departing from the gist of the present invention.
In the above embodiment, the case of an optical connector having a cylindrical ferrule has been described. However, the present invention is not limited to this, and can be applied to, for example, an optical connector having a substantially rectangular parallelepiped ferrule. In this case, if the width and thickness of the ferrule base (each of two lengths orthogonal to the connection direction of the optical connector) are smaller than the width and thickness of the ferrule tip member, the outer peripheral shape of the ferrule base is The outer peripheral shape of the ferrule tip member can be made smaller.
The structure of the clamp part is not particularly limited as long as it is a structure that aligns the optical fiber and clamps and holds the butt connection between the end faces. For example, the number of lids facing the substrate of the element may be one or more. The wedge insertion groove may be provided separately for each tip of the wedge, or may be connected to one as shown in the above embodiment.
The present invention can also be applied to an optical connector in which a plurality of optical fiber holes are formed in a ferrule and a connecting optical fiber is housed in each optical fiber hole. In this case, if the alignment mechanism such as the positioning groove provided in the clamp part is provided at least for the number of optical fibers for connection, each optical fiber terminated by the optical connector is connected by the alignment mechanism. The optical fiber can be optically connected. As such an optical connector, for example, an optical connector whose ferrule is an MT type optical connector ferrule (MT: Mechanically Transferable) defined in JIS C 5981 or the like is exemplified.

It is front view sectional drawing which shows the optical connector of this invention. FIG. 2 is a plan view sectional view showing the optical connector of FIG. 1. It is a left view which shows the optical connector of FIG. It is front view sectional drawing which shows the ferrule with a clamp part in the optical connector of FIG. FIG. 2 is a cross-sectional plan view showing a ferrule with a clamp portion in the optical connector of FIG. 1. 2A and 2B are views showing a housing body in the optical connector of FIG. 1, in which FIG. 1A is a plan view, FIG. 1B is a front view, FIG. 1C is a left side view, and FIG. It is drawing which shows the housing cover in the optical connector of FIG. 1, (a) is a top view, (b) is a front view, (c) is a left view, (d) is a right view. It is a disassembled perspective view of the optical connector of FIG. It is a perspective view which shows the state which made the optical connector and opening member of FIG. 1 oppose. It is sectional drawing which shows the state which inserted the wedge part of the open member with which the optical connector of FIG. 1 was mounted | worn in the clamp part of the optical connector. It is sectional drawing which shows the state which removed the wedge part of the open member with which the optical connector of FIG. 1 was mounted | worn from the clamp part of the optical connector. It is sectional drawing which shows a mode that another optical fiber is made to approach from the rear end side of the optical connector of FIG. It is sectional drawing which shows the state which inserted the other optical fiber from the rear end side of the optical connector of FIG. It is sectional drawing which shows the state which connected the optical fiber for connection and another optical fiber within the clamp part of the optical connector of FIG. It is sectional drawing which shows the state which inserted and connected the optical connector plug to the optical connector of FIG. FIG. 2 is a cross-sectional view illustrating a state where an optical connector plug is disposed opposite to the optical connector of FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Optical connector (optical connector receptacle), 2 ... Housing, 3 ... Ferrule, 4 ... Clamp part, 5 ... Opening member, 6 ... Optical connector (optical connector plug), 11 ... Optical connector accommodation hole, 23 ... Optical fiber insertion Hole, 23a ... curved surface, 24 ... rear end of housing (rear end of housing lid), 31 ... ferrule tip member, 32 ... joining end face, 34 ... optical fiber for connection, 34b ... rear end of ferrule of optical fiber for connection 36, ferrule base, 37 ... integral member (main member resin molding part), 41, 42, 43 ... element, 48 ... other optical fiber.

Claims (4)

A portion (34b) projecting from the rear end of the ferrule of the connection optical fiber and other light at the rear end facing the joining end surface (32) of the ferrule (3) in which the connection optical fiber (34) is preliminarily installed. A clamp part (4) for clamping and holding the butt connection state with the fiber (48) is provided, and the housing (2) for housing the ferrule and the clamp part is disposed opposite to the joining end face of the ferrule. An optical connector housing hole (11) for inserting and housing the optical connector (6) to be connected;
The housing includes a clamp portion storage portion (17) for storing the clamp portion, and a housing lid (20) fitted to the clamp portion storage portion, and the housing lid on the rear end (24) side of the housing. An optical fiber insertion hole (23) for inserting the other optical fiber into the clamp part is formed in the rear end wall (22) . There is a curved surface (23a) for ensuring a bending radius greater than the allowable bending radius so that the optical characteristics of the optical fiber can be maintained,
A tapered hole (45b) for inserting the other optical fiber (48) into the clamp part is opened at the rear end of the clamp part, and the curved surface is formed at the rear end (24) of the housing. The width of the curved surface is maximized, the maximum width is larger than the width of the rear end of the clamp part, and the diameter is reduced from the rear end of the housing toward the tapered hole of the rear end of the clamp part. The optical connector (1 ), wherein the curved surface (23a) is connected to a tapered hole (45b) at the rear end of the clamp portion in a state where the housing lid is integrated with the clamp portion storage portion. ).   The clamp portion includes a pair of elements (41, 42, 43) that sandwich the optical fibers, and the ferrule includes a ferrule base (36) formed as a member (37) integral with any of the elements. The optical connector according to claim 1, further comprising a ferrule tip member (31) made of a material harder than the integral member and joined to the ferrule base.   An opening member (5) for securing the open state of the clamp part is interposed in the clamp part, and the clamping force to the optical fiber by the clamp part acts by removing the open member. The optical connector according to claim 1, wherein the optical connector is formed.   The optical connector according to claim 1, wherein the optical connector is used for an outlet box.

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