JP2015034937A - Optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical connector which features more reliable mechanism for having tips of two optical fibers pressed against each other and does not use adhesives for assembling, which simplifies an assembling process and prevents failure.SOLUTION: An optical connector 1 includes a first housing 9 and second housing 38 to be engaged with each other, a first optical fiber 2 housed in the first housing 9, and a second optical fiber 3 housed in the second housing 38, and is configured to achieve an optical connection by having end surfaces of the first optical fiber 2 and the second optical fiber 3 butt against each other when the first housing 9 is engaged with the second housing 38. The second optical fiber 3, which is supported by the second housing 38 in a manner that allows movement along an axial direction and pressed in a direction of the connection by a coil spring 53, is pushed and displaced toward a side opposite the direction of the connection against the pressing force of the coil spring 53 by the first optical fiber 2 on the opposite side of the butt connection.

Description

  The present invention relates to an optical connector that performs optical connection by abutting two optical fiber terminals.

  In order to optically connect the optical fibers, it is necessary to perform end processing of the optical fibers. Conventionally, terminal processing for fixing an optical fiber to a ferrule with an adhesive is common. However, in the optical connector, deterioration of the adhesive for fixing the optical fiber to the ferrule and poor adhesion are one of the failure factors. Further, since the adhesive requires time for curing, it takes time to assemble the ferrule and the optical fiber. In addition, since the pot life of the adhesive is limited and it hardens and deteriorates with the passage of time, the handling requires attention, and the bonding process is often separated from all processes, resulting in a decrease in productivity. Moreover, epoxy adhesives are mainly used as an adhesive for fixing the optical fiber and the ferrule. However, since it is a two-component type, a process of mixing solvents is required.

  The following Patent Document 1 is a proposal made to solve the various problems as described above, and the optical connector disclosed here butts the end faces of the optical fiber without using a ferrule and an adhesive. To make an optical connection. More specifically, the optical connector includes a first optical fiber and a second optical fiber, and a resin-made first housing and a second housing that respectively accommodate the first optical fiber and the second optical fiber. Optical connection is made by abutting the end surfaces of the first optical fiber and the second optical fiber with the engagement.

JP 2006-317890 A

By the way, the optical connector of Patent Document 1 can solve the above-described problems, but has the following new problems.
(1) Since the optical fiber is bent and pressed, if the optical fiber is a glass optical fiber, there is a risk of breakage. If the optical fiber is a plastic optical fiber, the pressing force is secured by plastic deformation. It may not be possible.
Also, (2) when the optical fiber is plastically deformed into a bent shape, the tip of the optical fiber is drawn from a desired position when the optical connector is removed and the connection is released. For this reason, when the optical connector is repeatedly attached and detached, there is a possibility that the ends of the optical fibers do not come into contact with each other.
Further, (3) by providing a space for bending the optical fiber, the size of the optical connector increases in the longitudinal direction.

  The present invention has been made in view of the above-described circumstances, and an object thereof is a mechanism that presses the tips of optical fibers in an optical connector that abuts and connects the tips of optical fibers without using a ferrule. It is an object of the present invention to provide an optical connector that can improve the reliability of the apparatus and can simplify assembly and prevent failure by not using an adhesive for assembly.

In order to achieve the above-described object, an optical connector according to the present invention is characterized by the following (1) to (8).
(1) A first housing, a first optical fiber accommodated in the first housing, a second housing engaged with the first housing, and a second optical fiber accommodated in the second housing. ,
As the first housing and the second housing are engaged with each other, the end face of the first optical fiber and the end face of the second optical fiber are brought into contact with each other so that optical connection is performed. And
An elastic member held by one of the first housing and the second housing;
The one housing has a through-hole inserted through the optical fiber accommodated in the one housing, and holds the optical fiber movably along the axial direction.
The elastic member is fixed to the optical fiber, and is held by the one housing so as to urge the optical fiber along the axial direction in a state where the tip of the optical fiber protrudes from the through hole,
The optical fiber is displaced against the urging force of the elastic member by being pushed in while being abutted against the other optical fiber.
(2) An optical connector configured as described in (1) above,
The displacement dimension by which the optical fiber is displaced is smaller than the deformable dimension of the elastic member.
(3) An optical connector configured as described in (1) or (2) above,
The elastic member has a front end locked to the optical fiber,
The one housing has a spring stopper for locking the rear end of the elastic member.
(4) An optical connector configured as described in (3) above,
The one housing includes a housing main body and the spring stopper, and the spring stopper is detachable from the housing main body.
The spring stopper has a cutout portion through which the optical fiber is inserted, and the cutout portion is attached to the housing body while being inserted through the optical fiber.
(5) An optical connector configured as described in (1) or (2) above,
The elastic member is a helical coil spring through which the optical fiber is inserted,
The coil spring has a front end locked to the optical fiber and a rear end locked to the one housing.
(6) An optical connector configured as described in (5) above,
The front end of the coil spring is fixed by being crimped to the optical fiber.
(7) An optical connector configured as described in (6) above,
In the coil spring, the inner surface of the front end portion crimped to the optical fiber is roughened.
(8) An optical connector configured as described in (5) above,
The front end of the coil spring is locked to the optical fiber by an annular flange fixed to the optical fiber.

In the optical connector having the configuration (1), the elastic member is deformed at the time of fitting, so that it is possible to realize absorption of the extra length of the optical fiber and pressing between the tips of the optical fibers. For this reason, the bending of the optical fiber at the time of connection can be prevented. Therefore, even if a glass optical fiber is used as the optical fiber, the possibility of breakage can be eliminated, and even if a plastic optical fiber is used, the problem that the pressing force cannot be secured due to plastic deformation can be eliminated.
Further, since the optical fiber is displaced without being bent, even if the connection is released, the optical fiber is not plastically deformed and the tip position is not pulled from a predetermined position. For this reason, even if it attaches and detaches repeatedly, the malfunction that the front-end | tips of an optical fiber do not contact can be prevented.
In addition, there is no need for a space for bending the optical fiber, and therefore the size of the housing in the longitudinal direction can be reduced.
Further, since no adhesive is used to fix the optical fiber, assembly is easy and high reliability can be ensured.
In the optical connector having the configuration (2), the displacement dimension of the displaced optical fiber is smaller than the deformable dimension of the elastic member. Thereby, the elastic force of an elastic member can be reliably given to an optical fiber at the time of a connection, Therefore The front-end | tip part of a mutual optical fiber can be reliably faced | matched and optical connection can be performed favorably.
In the optical connector having the configuration (3), by attaching a spring stopper to the housing, it is possible to very easily lock the rear end portion of the elastic member and apply an elastic force to the optical fiber. it can.
In the optical connector having the configuration (4) described above, the spring stopper can be easily attached to the housing by passing the optical fiber through the notch portion of the spring stopper, and the assembly work can be facilitated.
In the optical connector having the configuration (5), by using a coil spring as the elastic member, it is possible to reliably apply an elastic force to the optical fiber at low cost.
In the optical connector having the configuration (6), the front end of the coil spring is fixed to the optical fiber by caulking the optical fiber, so that the cost can be reduced by simplifying the structure.
In the optical connector having the configuration (7), the inner surface of the front end portion crimped to the optical fiber of the coil spring can be securely fixed to the optical fiber by roughening the inner surface.
In the optical connector having the configuration (8), by using the flange, the coil spring can be locked to the optical fiber and an elastic force can be applied without processing the coil spring.

  According to the present invention, it is possible to improve the reliability of the mechanism that presses the tips of optical fibers in an optical connector that connects the tips of optical fibers by abutting each other without using a ferrule. By not using an adhesive, it is possible to provide an optical connector capable of simplifying assembly and preventing failure.

  The present invention has been briefly described above. Further, the details of the present invention will be further clarified by reading through a mode for carrying out the invention described below (hereinafter referred to as “embodiment”) with reference to the accompanying drawings. .

FIG. 1 is a cross-sectional view showing the configuration of the optical connector according to the first embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a perspective view of the spring stopper. FIG. 4A to FIG. 4D are views for explaining how to assemble the receptacle-side optical connector, and are sectional views, respectively. FIGS. 5A and 5B are views showing the connection state of the plug-side optical connector and the receptacle-side optical connector, respectively, and are cross-sectional views. FIG. 6 is a cross-sectional view of a plug-side optical connector for explaining an optical connector according to a second embodiment of the present invention. FIGS. 7A and 7B are diagrams for explaining the alignment portion of the plug-side optical connector, and are CC cross-sectional views in FIG. 6, respectively. FIGS. 8A and 8B are views showing the connection state of the plug-side optical connector and the receptacle-side optical connector, respectively, and are cross-sectional views. FIG. 9 is a cross-sectional view showing the configuration of the optical connector according to the third embodiment of the present invention. 10 (a) and 10 (b) are diagrams for explaining the plug-side V-groove and the receptacle-side V-groove, and FIG. 10 (a) is a sectional view taken along the line DD in FIG. 9, and FIG. 10 (b). FIG. 10 is an EE cross-sectional view in FIG. 9. FIG. 11A to FIG. 11C are diagrams showing a connection state of the plug-side optical connector and the receptacle-side optical connector, and are sectional views, respectively. 12 (a) and 12 (b) are diagrams for explaining the holding state of the optical fiber. FIG. 12 (a) is a cross-sectional view taken along line FF in FIG. 11 (b), and FIG. It is GG sectional drawing in FIG.11 (c). FIGS. 13A to 13D are views for explaining how to assemble the receptacle-side optical connector with the coil spring attached in the mounting structure according to the modification, and are respectively sectional views.

Hereinafter, an example of an embodiment according to the present invention will be described with reference to the drawings.
(First embodiment)
First, the optical connector according to the first embodiment will be described.
FIG. 1 is a cross-sectional view showing the configuration of the optical connector according to the first embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a perspective view of the spring stopper.

  As shown in FIG. 1, the optical connector 1 is a member for optically connecting the first optical fiber 2 and the second optical fiber 3, and is plug-side light provided at the end of the first optical fiber 2. A connector 4 and a receptacle-side optical connector 5 provided at the end of the second optical fiber 3 are provided.

First, the configuration and structure of the first optical fiber 2 and the second optical fiber 3 will be described.
Although the 1st optical fiber 2 and the 2nd optical fiber 3 are not specifically limited, the same thing is used. The first optical fiber 2 and the second optical fiber 3 include a resin / glass core / cladding portion 6 having optical transparency, a coating layer 7 covering the core / cladding portion 6, and a jacket (not shown). It is prepared for. The outer cover and the covering layer 7 are removed by a predetermined length and processed so that the core / cladding portion 6 is exposed. The first optical fiber 2 and the second optical fiber 3 are formed in a shape that is circular in cross section.

  The first optical fiber 2 and the second optical fiber 3 are illustrated as a single core in the first embodiment, but a plurality of the first optical fiber 2 and the second optical fiber 3 are arranged in the direction perpendicular to the paper surface of FIG. It is good also as a multi-core side by side. The first optical fiber 2 and the second optical fiber 3 in the figure are short, but actually a little longer.

Next, the configuration and structure of the optical connector will be described.
First, the configuration and structure of the plug-side optical connector 4 will be described.
The plug-side optical connector 4 includes a first optical fiber 2 and a first housing 9. In the first optical fiber 2, the coating layer 7 is removed by a predetermined dimension and the core / cladding portion 6 is exposed at the distal end side. The first housing 9 is a resin molded product, and as a resin material to be used, a resin material (for example, a material that does not break even when repeated engagement with the second housing 38 described later of the receptacle-side optical connector 5 is performed) PBT (polybutylene terephthalate)) is selected. Such a first housing 9 has a first housing front portion 12 and a first housing rear portion 14.

  The first housing front portion 12 is formed as an engagement portion with the second housing 38. A housing end surface 15 is formed at the tip of the first housing front portion 12. The housing end surface 15 is formed as a front end surface of the first housing 9.

  A guide surface 16 is formed on the inner surface of the first housing front portion 12. The guide surface 16 is formed as a surface for guiding an inner housing 40 described later of the second housing 38. A guide surface 25 is formed on the outer surface of the first housing front portion 12. The guide surface 25 is formed as a surface for guiding an outer housing 39 described later of the second housing 38. An engagement space 17 is formed in the first housing front portion 12. The engagement space 17 is disposed and formed inward of the housing end surface 15, and is defined by the guide surface 16. The inner housing 40 is inserted into the engagement space 17.

  An alignment portion 10 is formed in the first housing front portion 12. The aligning portion 10 is integrally formed with the first housing 9. The aligning portion 10 is formed with a tapered portion 18 at its tip that gradually becomes thinner toward the front. A non-tapered portion 19 having the same thickness in the front-rear direction is formed on the rear side of the tapered portion 18 of the aligning portion 10. Further, a rear taper portion 20 is formed on the rear side of the non-taper portion 19 and the thickness thereof is gradually increased toward the rear.

  The first housing 9 has a through hole 30 penetrating through the front and rear. The core / cladding portion 6 of the first optical fiber 2 is inserted into the through hole 30. As shown in FIG. 2, the inner diameter of the through hole 30 of the aligning portion 10 is set so that the core / cladding portion 6 of the first optical fiber 2 can be inserted. It is slightly larger than the diameter. The through-hole 30 is a coating layer insertion hole 31 having a large diameter at the rear portion 14 of the first housing. The portion of the coating layer 7 of the first optical fiber 2 is inserted through the coating layer insertion hole 31. The inner diameter of the coating layer insertion hole 31 is slightly larger than the outer diameter of the coating layer 7 portion of the first optical fiber 2 so that the coating layer 7 portion of the first optical fiber 2 can be inserted.

  The core / cladding portion 6 of the first optical fiber 2 from which the coating layer 7 is removed at the front end portion is inserted into the through hole 30 from the rear end side of the first housing 9. Then, the core / cladding portion 6 of the first optical fiber 2 is accommodated forward of the coating layer insertion hole 31. The portion of the coating layer 7 of the first optical fiber 2 is inserted through the coating layer insertion hole 31.

  The through hole 30 has a front end opening 33 that gradually increases in diameter toward the front at the tip of the aligning portion 10. In addition, a guide taper portion 34 that gradually narrows forward is formed at a boundary portion between the through hole 30 and the coating layer insertion hole 31. The guide taper portion 34 prevents the tip of the core / cladding portion 6 from being caught when the first optical fiber 2 is inserted into the through hole 30. The front end opening 33 prevents the tip of the core / cladding portion 6 from being caught when the second optical fiber 3 is inserted.

  The first optical fiber 2 inserted and accommodated in the through hole 30 is disposed at a position where the tip of the core / cladding portion 6 is drawn from the tip of the aligning portion 10. The tip position of the core / cladding portion 6 of the first optical fiber 2 is a position where it abuts against the tip of the core / cladding portion 6 of the second optical fiber 3. The first optical fiber 2 is fixed to the first housing 9 by an optical fiber fixing mechanism (not shown) and maintained in the state of being accommodated in the through hole 30.

Next, the configuration and structure of the receptacle-side optical connector 5 will be described.
The receptacle-side optical connector 5 includes the second optical fiber 3, the second housing 38, and a coil spring (elastic member) 53. The second optical fiber 3 has the core / cladding portion 6 exposed by removing the coating layer 7 by a predetermined dimension on the distal end side.

  A spiral coil spring 53 is attached to the second optical fiber 3. The inner diameter of the coil spring 53 is larger than the outer diameter of the coating layer 7. A portion of the coating layer 7 of the second optical fiber 3 is inserted into the coil spring 53. The coil spring 53 is fixed to the portion of the coating layer 7 of the second optical fiber 3 by caulking the front end side thereof. As the coil spring 53, an elastic material that is easily plastically deformed and has high rigidity is selected so that the coil spring 53 can be swaged and fixed to the coating layer 7 of the second optical fiber 3. As a material of the coil spring 53, for example, a metal material such as brass, aluminum, or stainless steel is used.

  The second housing 38 is a resin molded product, and as a resin material to be used, a resin material that does not break even when the plug-side optical connector 4 is repeatedly engaged with the first housing 9 (for example, PBT ( Polybutylene terephthalate)) is selected. Such a second housing 38 has a second housing front portion 41, a second housing rear portion 42, and a spring stopper 55.

  The second housing 38 has an outer housing 39 and an inner housing 40 in the second housing front portion 41, and a spring accommodating space 43 in the second housing rear portion 42.

  The inner housing 40 is disposed and formed inside the outer housing 39. The second housing rear portion 42 is disposed and formed so as to be continuous with the rear side of the outer housing 39 and the inner housing 40.

  The outer housing 39 is formed as an engagement portion with the first housing 9. A housing end surface 44 is formed at the tip of the outer housing 39. The housing end surface 44 is formed as a front end surface of the second housing 38. A guide surface 45 that is guided by the guide surface 25 on the outer surface side of the first housing 9 is formed on the inner surface of the outer housing 39. The outer housing 39 is formed with a tapered portion 49 that gradually expands forward at the tip.

  Similar to the outer housing 39, the inner housing 40 is formed as an engagement portion with the first housing 9. The inner housing 40 is also formed as an engagement portion with the aligning portion 10 of the plug-side optical connector 4. A guide surface 46 that is guided by the guide surface 16 on the inner surface side of the first housing 9 is formed on the outer surface of the inner housing 40.

  An insertion portion 48 is formed on the distal end surface 47 of the inner housing 40 by recessing the distal end surface 47. The insertion portion 48 is formed in a concave shape that is substantially concave, and is integrally formed with the inner housing 40. The insertion portion 48 is formed in a shape that allows the alignment portion 10 to be inserted. The insertion portion 48 has an inner diameter that is larger than the outer diameter of the second optical fiber 3.

  A groove 50 into which the first housing front portion 12 of the first housing 9 is inserted is formed between the outer housing 39 and the inner housing 40. The groove 50 is formed to a depth such that the housing end surface 15 of the first housing 9 does not contact the bottom.

  The second housing 38 has a through hole 51 penetrating through the front and rear. The through hole 51 is formed as a hole having a circular cross section that penetrates straight from the bottom surface 48 a of the insertion portion 48 of the inner housing 40 toward the rear end of the second housing rear portion 42. The core / cladding portion 6 of the second optical fiber 3 is inserted into the through hole 51. The second optical fiber 3 inserted through the through hole 51 is held in the through hole 51 so as to be movable in the axial direction. The inner diameter of the through hole 51 is slightly larger than the outer diameter of the core / cladding portion 6 of the second optical fiber 3 so that the core / cladding portion 6 of the second optical fiber 3 can be inserted. The through hole 51 communicates with a spring accommodating space 43 formed in the second housing rear portion 42. A coil spring 53 attached to the coating layer 7 of the second optical fiber 3 is inserted into the spring accommodating space 43. The inner diameter of the spring accommodating space 43 is slightly larger than the outer diameter of the coil spring 53 so that the coil spring 53 can be inserted.

  In addition, a guide taper portion 52 that gradually narrows forward is formed at a boundary portion between the through hole 51 and the spring accommodating space 43. The guide taper portion 52 prevents the tip of the core / cladding portion 6 from being caught when the second optical fiber 3 is inserted into the through hole 51.

  The core / cladding portion 6 of the second optical fiber 3 from which the coating layer 7 is removed at the tip portion is inserted into the through hole 51 from the rear end side of the second housing 38. The core / cladding portion 6 of the second optical fiber 3 is accommodated forward of the spring accommodating space 43. The core / cladding portion 6 of the second optical fiber 3 inserted into the through hole 51 is disposed so that the tip protrudes from the bottom surface 48 a of the insertion portion 48. Further, the portion of the coating layer 7 of the second optical fiber 3 where the coil spring 53 is mounted is accommodated in the spring accommodating space 43.

  The spring stopper 55 is attached to the rear end of the second housing rear portion 42 of the second housing 38. As shown in FIG. 3, the spring stopper 55 is formed in a box shape having an opening 56 on the mounting side to the second housing rear portion 42. The spring stopper 55 is attached to the second housing 38 by fitting the rear end of the second housing rear portion 42 into the opening 56. An engagement groove 57 is formed on the inner surface of the spring stopper 55. By attaching the spring stopper 55 to the second housing 38, the engagement protrusion 59 formed on the outer surface of the second housing rear portion 42 is engaged with the engagement groove 57 of the spring stopper 55. Thereby, the spring stopper 55 is maintained in a state where it is mounted on the second housing 38. The spring stopper 55 has a notch 63 formed from a side plate 61 forming one side surface to a bottom plate 62 forming a bottom surface. The width dimension of the notch 63 is larger than the outer diameter of the portion of the coating layer 7 of the second optical fiber 3 and smaller than the outer diameter of the coil spring 53. When attaching the spring stopper 55 to the second housing rear portion 42, first, the second optical fiber 3 is passed through the notch portion 63 and then fitted to the second housing rear portion 42. The spring stopper 55 is attached to the second housing rear portion 42, whereby the coil spring 53 is locked and maintained in the state of being accommodated in the spring accommodating space 43 of the second housing 38.

  Instead of the notch 63, a hole that is larger than the outer diameter of the coating layer 7 of the second optical fiber 3 and smaller than the outer diameter of the coil spring 53 is formed in the bottom plate 62 of the spring stopper 55. May be. In this case, the second optical fiber 3 is inserted in advance through the hole of the bottom plate 62 of the spring stopper 55, the coil spring 53 is attached to the second optical fiber 3, and the second optical fiber 3 is inserted into the through hole 51. After that, the spring stopper 55 is attached to the rear portion 42 of the second housing.

Next, how to assemble the optical connector will be described.
First, how to assemble the plug-side optical connector 4 will be described.

  To assemble the plug-side optical connector 4, first, the coating layer 7 of the first optical fiber 2 is peeled to a predetermined length to expose the core / cladding portion 6 so that the end surface of the core / cladding portion 6 is smooth. Process.

  Next, the first optical fiber 2 is inserted into the through hole 30 of the aligning part 10 until the coating layer 7 hits the step of the through hole 30 of the aligning part 10. At this time, the length at which the coating layer 7 of the first optical fiber 2 is peeled off is adjusted so that the tip position of the core / cladding portion 6 of the first optical fiber 2 is disposed within the range B in FIG.

  When the optical fiber connector 5 is fitted with the receptacle-side optical connector 5, the length of the second optical fiber 3 inserted into the through hole 30 of the aligning portion 10 is about four times or more the outer diameter of the optical fiber. Setting the tip position of the fiber 2 prevents the tip of the second optical fiber 3 from being inclined. For example, when the outer diameter of the optical fiber is 0.5 mm, the first optical fiber 2 is drawn from the tip of the alignment part 10 by 2 mm or more.

  Thereafter, the covering layer 7 of the first optical fiber 2 is fixed to the first housing 9 by an optical fiber fixing mechanism (for example, caulking, wedge, adhesion, welding, etc.), and the plug-side optical connector 4 is disconnected from the first optical fiber 2. To prevent.

Next, how to assemble the receptacle-side optical connector 5 will be described.
FIG. 4A to FIG. 4D are views for explaining how to assemble the receptacle-side optical connector, and are sectional views, respectively.

  First, as shown in FIG. 4A, the coating layer 7 of the second optical fiber 3 is peeled to a predetermined length to expose the core / cladding portion 6 so that the end surface of the core / cladding portion 6 is smooth. Process.

  Next, the second optical fiber 3 whose end has been processed is inserted into the coil spring 53.

  Then, the distal end side of the coil spring 53 is caulked in the vicinity of the end of the coating layer 7 of the second optical fiber 3. In this way, the coil spring 53 is fixed to the coating layer 7 of the second optical fiber 3. When the coil spring 53 is caulked, the inner diameter of the coil spring 53 is deformed to be, for example, about 5% of the outer diameter of the coating layer 7. Further, in order to prevent the coil spring 53 from coming off from the second optical fiber 3, the surface roughness of the inner surface of the coil spring 53 is set so that the frictional force between the portion where the coil spring 53 is crimped and the coating layer 7 is increased. Keep it rough.

  Next, as shown in FIG. 4C, the second optical fiber 3 is inserted into the through hole 51 of the second housing 38 from the rear side of the second housing 38, and the core / cladding portion of the second optical fiber 3 is inserted. 6 is arranged at a position where the tip position of 6 protrudes from the bottom surface 48 a of the insertion portion 48. The protruding length L1 of the second optical fiber 3 from the bottom surface 48a of the insertion portion 48 is based on a distance L2 from the tip of the first optical fiber 2 to the bottom surface 48a of the insertion portion 48 when the plug-side optical connector 4 is fitted. Lengthen. The difference (L1−L2) between the protrusion length L1 and the distance L2 is the displacement dimension of the second optical fiber 3. The displacement dimension (L1-L2), which is the difference between the protruding length L1 and the distance L2, is adjusted to be shorter than the deformable dimension L3 that is the maximum value of the coil spring 53 that can be compressed and deformed. That is, adjustment is performed so that the following equation is established between the displacement dimension (L1-L2) and the deformable dimension L3. Note that the protruding length L1 of the second optical fiber 3 is adjusted by the length at which the coating layer 7 is peeled off.

    0 <L1-L2 <L3

  Thereafter, as shown in FIG. 4D, the spring stopper 55 is fitted from the rear end of the second housing 38. In this manner, the spring stopper 55 is fixed to the second housing 38 by the engagement protrusion 59 of the second housing rear portion 42 engaging with the engagement groove 57 of the spring stopper 55. When the spring stopper 55 is fixed and attached to the second housing 38, the coil spring 53 is pushed forward by the spring stopper 55 and is slightly compressed and is housed and held in the spring housing space 43. .

Next, how to connect the optical connector will be described.
FIGS. 5A and 5B are views showing the connection state of the plug-side optical connector and the receptacle-side optical connector, respectively, and are cross-sectional views.

  In order to connect the plug side optical connector 4 and the receptacle side optical connector 5, the plug side optical connector 4 and the receptacle side optical connector 5 are brought close to each other.

  Then, as shown in FIG. 5A, the first housing front portion 12 of the plug-side optical connector 4 enters inside the outer housing 39 of the receptacle-side optical connector 5, and is formed in the inner housing 40 of the receptacle-side optical connector 5. The alignment portion 10 of the plug-side optical connector 4 enters the inserted portion 48 while being guided by the tapered portion 18.

  The tip of the core / cladding portion 6 of the second optical fiber 3 of the receptacle-side optical connector 5 is inserted into the through hole 30 of the alignment portion 10 of the plug-side optical connector 4. Thereby, the end surface of the first optical fiber 2 of the plug-side optical connector 4 and the end surface of the second optical fiber 3 of the receptacle-side optical connector 5 are brought into contact with each other.

  Further, when the plug-side optical connector 4 and the receptacle-side optical connector 5 approach each other, as shown in FIG. 5B, the end surface of the first optical fiber 2 of the plug-side optical connector 4 and the receptacle-side optical connector 5 The first housing front portion 12 of the plug-side optical connector 4 further enters the inner side of the outer housing 39 of the receptacle-side optical connector 5 in a state where the end faces of the second optical fiber 3 face each other, and the receptacle-side optical connector 5 The alignment portion 10 of the plug-side optical connector 4 further enters the insertion portion 48 formed in the inner housing 40. When the plug-side optical connector 4 and the receptacle-side optical connector 5 are completely fitted, the first housing 9 and the second housing 9 are locked by the locking mechanism (not shown) provided in the first housing 9 and the second housing 38. The housing 38 is engaged with each other and maintained in a fitted state.

  Thus, when the plug-side optical connector 4 and the receptacle-side optical connector 5 are fitted, the second optical fiber 3 of the receptacle-side optical connector 5 is pushed backward with respect to the second housing 38. When the second optical fiber 3 is pushed backward with respect to the second housing 38, the coil spring 53 is compressed and deformed in the longitudinal direction, and the extra length portion of the second optical fiber 3 is the second housing rear portion 42 of the second housing 38. It is drawn to the side. At this time, the second optical fiber 3 is urged and pressed against the first optical fiber 2 by the reaction force of the compressive deformation formed by the elastic force of the coil spring 53. As a result, the core / cladding portion 6 of the first optical fiber 2 and the core / cladding portion 6 of the second optical fiber 3 are maintained in contact with each other.

  Further, the extra length of the second optical fiber 3 held by the receptacle-side optical connector 5 is absorbed by the compression deformation of the coil spring 53. Thereby, management of the drawing-in length of the 1st optical fiber 2 hold | maintained at the plug side optical connector 4 and the protrusion length of the 2nd optical fiber 3 becomes easy.

  As described above, according to the optical connector according to the first embodiment, when the plug-side optical connector 4 and the receptacle-side optical connector 5 are fitted, the coil spring 53 is compressed and deformed, so that the second optical fiber 3 is compressed. Absorption of the remaining length and pressing of the tips of the first optical fiber 2 and the second optical fiber 3 can be realized. For this reason, the bending of the 1st optical fiber 2 and the 2nd optical fiber 3 at the time of a connection can be prevented. Therefore, even if glass optical fibers are used as the first optical fiber 2 and the second optical fiber 3, there is no risk of breakage, and even if a plastic optical fiber is used, the pressing force cannot be secured due to plastic deformation. Can be eliminated.

  Further, since the second optical fiber 3 is displaced without being bent, the second optical fiber 3 is not plastically deformed and the tip position is not drawn from a predetermined position even if the connection is released. For this reason, even if the plug-side optical connector 4 and the receptacle-side optical connector 5 are repeatedly attached and detached, it is possible to prevent a problem that the tips of the first optical fiber 2 and the second optical fiber 3 are not in contact with each other.

  In addition, a space for bending the second optical fiber 3 is not required, and therefore the size of the second housing 38 in the longitudinal direction can be reduced.

  Moreover, since no adhesive is used to fix the first optical fiber 2 and the second optical fiber 3, assembly is easy and high reliability can be ensured.

  Further, the displacement dimension (L1-L2) of the second optical fiber 3 displaced by the opposed first optical fiber 2 is made smaller than the deformable dimension (L3) of the coil spring 53. Thereby, at the time of connection, the elastic force of the coil spring 53 can be reliably applied to the second optical fiber 3, and thus the distal end portions of the first optical fiber 2 and the second optical fiber 3 are reliably abutted against each other. Can be optically connected.

  In addition, by using the coil spring 53 as the elastic member, it is possible to reliably apply an elastic force to the second optical fiber 3 at a low cost.

  In addition, since the tip of the coil spring 53 is fixed to the second optical fiber 3 by crimping the second optical fiber 3, the cost can be reduced by simplifying the structure.

  Further, by roughening the inner surface of the front end portion of the coil spring 53 that is crimped to the second optical fiber 3, the coil spring 53 can be reliably fixed to the second optical fiber 3.

  Further, by attaching the spring stopper 55 to the second housing 38, the rear end portion of the coil spring 53 can be locked very easily, and the elastic force can be applied to the second optical fiber 3. .

  Further, by passing the second optical fiber 3 through the notch 63 of the spring stopper 55, the spring stopper 55 can be easily attached to the second housing 38, and the assembling work can be facilitated.

  In particular, according to the first embodiment, when the plug-side optical connector 4 and the receptacle-side optical connector 5 are fitted, the outer diameters of the first optical fiber 2 and the second optical fiber 3 and the through-hole 30 of the aligning portion 10. There is almost no gap (clearance) in the inner diameter of the first optical fiber 2, and hence the axial deviation between the first optical fiber 2 and the second optical fiber 3 can be suppressed. For this reason, a low-loss optical connection can be realized.

  Further, since the aligning portion 10 has the function of holding the tips of the first optical fiber 2 and the second optical fiber 3, it is possible to eliminate the possibility that the optical connection loss increases due to vibration or impact.

  In addition, since high accuracy is not required for the through hole 30 of the aligning portion 10, the fabrication can be facilitated and the yield can be improved.

  Further, since the aligning portion 10 can be integrally formed with the first housing 9 and the insertion portion 48 can be integrally formed with the second housing 38, the component cost of the optical connector 1 can be reduced.

  In the first embodiment, the aligning portion 10 is provided in the first housing 9 of the plug-side optical connector 4 and the insertion portion 48 is provided in the second housing 38 of the receptacle-side optical connector 5. May be provided in the second housing 38 of the receptacle-side optical connector 5, and the insertion portion 48 may be provided in the first housing 9 of the plug-side optical connector 4.

  In the first embodiment, the second optical fiber 3 of the receptacle-side optical connector 5 is pressed and held by the coil spring 53, but the first optical fiber 2 of the plug-side optical connector 4 is pressed and held by the coil spring 53. Alternatively, both the first optical fiber 2 of the plug-side optical connector 4 and the second optical fiber 3 of the receptacle-side optical connector 5 may be pressed and held by the coil spring 53.

(Second Embodiment)
Next, an optical connector according to the second embodiment will be described.
Note that the same components as those of the optical connector according to the first embodiment are denoted by the same reference numerals and description thereof is omitted.

  FIG. 6 is a cross-sectional view of a plug-side optical connector for explaining an optical connector according to a second embodiment of the present invention. FIGS. 7A and 7B are diagrams for explaining the alignment portion of the plug-side optical connector, and are CC cross-sectional views in FIG. 6, respectively. FIGS. 8A and 8B are views showing the connection state of the plug-side optical connector and the receptacle-side optical connector, respectively, and are cross-sectional views.

  As shown in FIGS. 6 and 7A, in the optical connector 1A according to the second embodiment, three slits 10a along the axial direction are formed in the alignment portion 10 of the plug-side optical connector 4 from the intermediate portion to the tip portion. Is formed over. These slits 10a are formed at equal intervals in the circumferential direction. Thereby, the alignment part 10 is provided with the three division bodies 10b arrange | positioned with respect to the central axis of the through-hole 30 in which the core / cladding part 6 of the 1st optical fiber 2 is penetrated. In the aligning portion 10, the outer diameter of the non-tapered portion 19 is slightly larger than the inner diameter of the insertion portion 48 of the receptacle-side optical connector 5. As shown in FIG. 7B, as the aligning portion 10, four slits 10 a are formed along the axial direction, and the four divided bodies 10 b are located at point-symmetric positions with respect to the central axis of the through hole 30. An arranged structure may be used.

  Note that the method of assembling the plug-side optical connector 4 and the receptacle-side optical connector 5 in the optical connector 1A according to the second embodiment is the same as that in the first embodiment, and thus the description thereof is omitted.

  Next, the case where the plug side optical connector 4 and the receptacle side optical connector 5 are connected will be described.

  In order to connect the plug side optical connector 4 and the receptacle side optical connector 5, the plug side optical connector 4 and the receptacle side optical connector 5 are brought close to each other.

  Then, as shown in FIG. 8A, the first housing front portion 12 of the plug-side optical connector 4 enters the inner side of the outer housing 39 of the receptacle-side optical connector 5 and is formed in the inner housing 40 of the receptacle-side optical connector 5. The alignment portion 10 of the plug-side optical connector 4 enters the inserted portion 48 while being guided by the tapered portion 18.

  The tip of the core / cladding portion 6 of the second optical fiber 3 of the receptacle-side optical connector 5 is inserted into the through hole 30 of the alignment portion 10 of the plug-side optical connector 4. Thereby, the end surface of the first optical fiber 2 of the plug-side optical connector 4 and the end surface of the second optical fiber 3 of the receptacle-side optical connector 5 are brought into contact with each other.

  Further, when the plug-side optical connector 4 and the receptacle-side optical connector 5 approach each other, as shown in FIG. 8B, the end face of the first optical fiber 2 of the plug-side optical connector 4 and the receptacle-side optical connector 5 The first housing front portion 12 of the plug-side optical connector 4 further enters the inner side of the outer housing 39 of the receptacle-side optical connector 5 in a state where the end faces of the second optical fiber 3 face each other, and the receptacle-side optical connector 5 The alignment portion 10 of the plug-side optical connector 4 further enters the insertion portion 48 formed in the inner housing 40. When the plug-side optical connector 4 and the receptacle-side optical connector 5 are completely fitted, the first housing 9 and the second housing 9 are locked by the locking mechanism (not shown) provided in the first housing 9 and the second housing 38. The housing 38 is engaged with each other and maintained in a fitted state.

  Further, the aligning portion 10 formed to have a diameter slightly larger than the inner diameter of the insertion portion 48 is fitted into the insertion portion 48, so that the plurality of divided bodies 10 b of the alignment portion 10 are directed toward the center of the through hole 30. And elastically deforms. Thereby, the divided body 10b of the aligning portion 10 is pressed around the mutually abutted tip portions of the core / cladding portion 6 of the first optical fiber 2 and the core / cladding portion 6 of the second optical fiber 3. Therefore, the periphery of the mutually abutted tip portions of the core / cladding portion 6 of the first optical fiber 2 and the core / cladding portion 6 of the second optical fiber 3 is securely held by the divided body 10b that is pressed evenly. It will be.

  The alignment portion 10 is fitted into the insertion portion 48 and the inner diameter of the through hole 30 is the core / core of the first optical fiber 2 and the second optical fiber 3 when the divided body 10b is elastically deformed toward the center. It is preferable to form it so as to be smaller than the outer diameter of the clad portion 6 by about 1% to 5%. In this way, the tip of the core / cladding portion 6 of the first optical fiber 2 and the second optical fiber 3 can be securely held without rattling, and even if an external force such as an impact acts, The leading ends of the core / cladding portions 6 of the first optical fiber 2 and the second optical fiber 3 can be sufficiently retained.

  Also in the case of the second embodiment, when the plug-side optical connector 4 and the receptacle-side optical connector 5 are fitted, the second optical fiber 3 of the receptacle-side optical connector 5 is pushed backward with respect to the second housing 38. . When the second optical fiber 3 is pushed backward with respect to the second housing 38, the coil spring 53 is compressed and deformed in the longitudinal direction, and the extra length portion of the second optical fiber 3 is the second housing rear portion 42 of the second housing 38. It is drawn to the side. At this time, the second optical fiber 3 is urged and pressed against the first optical fiber 2 by the reaction force of the compressive deformation formed by the elastic force of the coil spring 53. As a result, the core / cladding portion 6 of the first optical fiber 2 and the core / cladding portion 6 of the second optical fiber 3 are maintained in contact with each other.

  Thus, also in the case of the optical connector 1A according to the second embodiment, when the plug-side optical connector 4 and the receptacle-side optical connector 5 are fitted, the coil spring 53 is compressed and deformed, so Long absorption and pressing of the tips of the first optical fiber 2 and the second optical fiber 3 can be realized. For this reason, the bending of the 1st optical fiber 2 and the 2nd optical fiber 3 at the time of a connection can be prevented. Therefore, even if glass optical fibers are used as the first optical fiber 2 and the second optical fiber 3, there is no risk of breakage, and even if a plastic optical fiber is used, the pressing force cannot be secured due to plastic deformation. Can be eliminated.

  Further, since the second optical fiber 3 is displaced without being bent, the second optical fiber 3 is not plastically deformed and the tip position is not drawn from a predetermined position even if the connection is released. For this reason, even if the plug-side optical connector 4 and the receptacle-side optical connector 5 are repeatedly attached and detached, it is possible to prevent a problem that the tips of the first optical fiber 2 and the second optical fiber 3 are not in contact with each other.

  In addition, there is no need for a space for bending the second optical fiber 3, and thus the size of the second housing 38 can be reduced in the longitudinal direction.

  Moreover, since no adhesive is used to fix the first optical fiber 2 and the second optical fiber 3, assembly is easy and high reliability can be ensured.

  In particular, in the second embodiment, the divided body 10b of the aligning portion 10 is uniformly pressed around the tip portions of the first optical fiber 2 and the second optical fiber 3 that are abutted against each other. And the 2nd optical fiber 3 can be hold | maintained more reliably by the division body 10b.

  Note that the cross-sectional shape of the aligning portion 10 may be a shape that applies an equal pressure around the core / cladding portion 6 when fitted to the insertion portion 48.

  Also in the second embodiment, the aligning portion 10 is provided in the first housing 9 of the plug-side optical connector 4 and the insertion portion 48 is provided in the second housing 38 of the receptacle-side optical connector 5. The portion 10 may be provided in the second housing 38 of the receptacle-side optical connector 5, and the insertion portion 48 may be provided in the first housing 9 of the plug-side optical connector 4.

  Also in the second embodiment, the second optical fiber 3 of the receptacle-side optical connector 5 is pressed and held by the coil spring 53, but the first optical fiber 2 of the plug-side optical connector 4 is pressed by the coil spring 53. Alternatively, both the first optical fiber 2 of the plug side optical connector 4 and the second optical fiber 3 of the receptacle side optical connector 5 may be pressed and held by the coil spring 53.

(Third embodiment)
Next, an optical connector according to a third embodiment will be described.
Note that the same components as those of the optical connector according to the first embodiment or the second embodiment are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 9 is a cross-sectional view showing the configuration of the optical connector according to the third embodiment of the present invention. 10 (a) and 10 (b) are diagrams for explaining the plug-side V-groove and the receptacle-side V-groove, and FIG. 10 (a) is a sectional view taken along the line DD in FIG. 9, and FIG. 10 (b). FIG. 10 is an EE cross-sectional view in FIG. 9.

  As shown in FIG. 9, the optical connector 1 </ b> B includes a plug-side optical connector 64 provided at the end of the first optical fiber 2 and a receptacle-side optical connector 65 provided at the end of the second optical fiber 3. The

  The plug-side optical connector 64 includes the first optical fiber 2, the first housing 69, and the coil spring 53.

  In the first optical fiber 2, the coating layer 7 is removed by a predetermined dimension and the core / cladding portion 6 is exposed at the distal end side.

  A coil spring 53 is attached to the first optical fiber 2. The inner diameter of the coil spring 53 is larger than the outer diameter of the coating layer 7. The portion of the coating layer 7 of the first optical fiber 2 is inserted into the coil spring 53. The coil spring 53 is fixed to the portion of the coating layer 7 of the first optical fiber 2 by caulking the tip side. For the coil spring 53, an elastic material that is easily plastically deformed and highly synthesized is selected so that the coil spring 53 can be crimped and fixed to the coating layer 7 of the first optical fiber 2. As a material of the coil spring 53, for example, a metal material such as brass, aluminum, or stainless steel is used.

  The first housing 69 is a resin molded product, and as a resin material to be used, a resin material that does not break even if the receptacle-side optical connector 65 is repeatedly engaged with a second housing 88 described later (for example, PBT (polybutylene terephthalate)) is selected. Such a first housing 69 has a first housing front portion 72, a first housing rear portion 74, and a spring stopper 55.

  The first housing front portion 72 is formed as an engagement portion with the second housing 88. A housing end surface 75 is formed at the tip of the first housing front portion 72. The housing end surface 75 is formed as a surface at the front end position in the first housing 69.

  The first housing front part 72 is formed with a guide part 77 and a pressing part 78 extending forward. A pressing portion insertion space 79 is formed in the first housing front portion 72 between the guide portion 77 and the pressing portion 78. The guide portion 77 has a plug-side V-groove 80 extending on the pressing portion 78 side and extending to the tip of the first housing 69 along the axial direction. The plug-side V groove 80 accommodates the core / cladding portion 6 of the first optical fiber 2. As shown in FIG. 10A, the angle of each wall surface 80a of the plug-side V-groove 80 is 45 ° with respect to the vertical downward direction. As a result, the first optical fiber 2 accommodated in the plug-side V-groove 80 receives pressure equally from each wall surface 80a. The depth of the plug-side V-groove 80 is slightly smaller than the radius of the core / cladding portion 6 of the first optical fiber 2. Accordingly, the core / cladding portion 6 of the first optical fiber 2 accommodated in the plug-side V-groove 80 is disposed outside the plug-side V-groove 80 with the center O below the lower surface of the guide portion 77.

  The pressing portion 78 has a stepped portion 82 on the first housing rear portion 74 side. The step portion 82 is formed with a pressing guide surface 83 that is gradually inclined toward the guide portion 77 toward the first housing rear portion 74. The pressing guide surface 83 has a function of pressing a later-described pressing portion 93 of the receptacle-side optical connector 65 toward the guide portion 77.

  A through-hole 84 is formed in the first housing rear portion 74 so as to penetrate through the front and rear. The first housing rear portion 74 is formed with a spring accommodating space 85 communicating with the through hole 84 on the rear end side. The through hole 84 communicates with the plug-side V groove 80. The core / cladding portion 6 of the first optical fiber 2 is inserted into the through hole 84. The first optical fiber 2 inserted through the through hole 84 is held in the through hole 84 so as to be movable along the axial direction. The inner diameter of the through hole 84 is slightly larger than the outer diameter of the core / cladding portion 6 of the first optical fiber 2 so that the core / cladding portion 6 of the first optical fiber 2 can be inserted. A coil spring 53 attached to the coating layer 7 of the first optical fiber 2 is inserted into the spring accommodating space 85. The inner diameter of the spring accommodating space 85 is slightly larger than the outer diameter of the coil spring 53 so that the coil spring 53 can be inserted.

  In addition, a guide taper portion 86 that gradually narrows forward is formed at a boundary portion between the through hole 84 and the spring accommodating space 85. The guide taper portion 86 prevents the tip of the core / cladding portion 6 from being caught when the first optical fiber 2 is inserted into the through hole 84.

  The core / cladding portion 6 of the first optical fiber 2 from which the coating layer 7 is removed at the tip portion is inserted into the through hole 84 from the rear end side of the first housing 69. Then, the core / cladding portion 6 of the first optical fiber 2 is accommodated forward of the spring accommodating space 85. The core / cladding portion 6 of the first optical fiber 2 inserted into the through hole 84 is disposed so that the tip portion protrudes from the first housing rear portion 74 to the first housing front portion 72 side. The tip of the core / cladding portion 6 protruding toward the first housing front portion 72 is accommodated in the plug-side V-groove 80. Further, the portion of the coating layer 7 of the first optical fiber 2 where the coil spring 53 is mounted is accommodated in the spring accommodating space 85.

  A spring stopper 55 is mounted on the rear end side of the first housing rear portion 74. The first housing rear portion 74 is formed with an engaging protrusion 87 that engages with the engaging groove 57 of the spring stopper 55 and maintains the spring stopper 55 in a mounted state. Then, by attaching the spring stopper 55 to the first housing rear portion 74, the coil spring 53 is maintained in a state of being accommodated in the spring accommodating space 85 of the first housing 69.

  The receptacle-side optical connector 65 includes the second optical fiber 3 and a second housing 88.

  The second optical fiber 3 has the core / cladding portion 6 exposed by removing the coating layer 7 by a predetermined dimension on the distal end side.

  The second housing 88 is a resin molded product, and the resin material used is not damaged even when the plug-side optical connector 64 is repeatedly engaged with the first housing 69, and a pressing portion to be described later A resin material (for example, PBT (polybutylene terephthalate)) capable of elastically deforming 93 is selected. Such a second housing 88 has a second housing front portion 91 and a second housing rear portion 92.

  The second housing front portion 91 is formed as an engagement portion with the first housing 69. A housing end surface 91 a is formed at the tip of the second housing front portion 91. The housing end surface 91 a is formed as a surface at the front end position in the second housing 88.

  The second housing front portion 91 is formed with a holding portion 93 and a holding portion 94 that extend forward. In the second housing front portion 91, a guide portion insertion space 95 is formed between the pressing portion 93 and the holding portion 94. A receptacle-side V-groove 96 that extends to the tip of the second housing 88 along the axial direction is formed in the pressing portion 93 on the holding portion 94 side. The core / cladding portion 6 of the second optical fiber 3 is accommodated in the receptacle-side V-groove 96. As shown in FIG. 10B, the angle of each wall surface 96a of the receptacle-side V-groove 96 is 45 °. As a result, the second optical fiber 3 accommodated in the receptacle-side V-groove 96 receives pressure evenly from each wall surface 96a. The depth of the receptacle-side V-groove 96 is slightly smaller than (√2) times the radius of the core / cladding portion 6 of the second optical fiber 3. Accordingly, the core / cladding portion 6 of the second optical fiber 3 accommodated in the receptacle-side V-groove 96 is disposed outside the receptacle-side V-groove 96 with the center O above the upper surface of the pressing portion 93.

  A thin portion 97 having a reduced thickness is formed near the second housing rear portion 92 of the pressing portion 93. Also. A pressing guide surface 98 is formed at the distal end of the pressing portion 93 so as to incline toward the opposite side of the holding portion 94 toward the rear. The pressing guide surface 98 has a function of slidingly contacting the pressing guide surface 83 of the pressing portion 78 of the plug side optical connector 64 and guiding the pressing portion 93 to the holding portion 94 side.

  A through-hole 99 is formed in the second housing rear portion 92 so as to penetrate through the front and rear. The through hole 99 communicates with the receptacle-side V groove 96. The core / cladding portion 6 of the second optical fiber 3 is inserted through the through hole 99. The inner diameter of the through hole 99 is slightly larger than the outer diameter of the core / cladding portion 6 of the second optical fiber 3 so that the core / cladding portion 6 of the second optical fiber 3 can be inserted.

  The core / cladding portion 6 of the second optical fiber 3 from which the coating layer 7 is removed at the tip portion is inserted into the through hole 99 from the rear end side of the second housing 88. Then, the core / cladding portion 6 of the second optical fiber 3 inserted into the through hole 99 is disposed so that the tip portion protrudes from the second housing rear portion 92 to the second housing front portion 91 side. The leading end portion of the core / cladding portion 6 protruding toward the second housing front portion 91 side is accommodated in the receptacle-side V-groove 96.

  The second optical fiber 3 is fixed to the second housing 88 by an optical fiber fixing mechanism (for example, caulking, wedge, adhesion, welding, etc.) and maintained in the through hole 99.

  In the optical connector 1B having the above structure, the position of the center O of the first optical fiber 2 held by the plug-side optical connector 64 and the position of the center O of the second optical fiber 3 held by the receptacle-side optical connector 65 are shown in FIG. 9 is slightly shifted in the vertical direction (arrow Y direction). Specifically, in FIG. 9, the center O of the second optical fiber 3 of the receptacle-side optical connector 65 is opposite to the guide portion 77 with respect to the center O of the first optical fiber 2 of the plug-side optical connector 64. The center O of the first optical fiber 2 of the plug-side optical connector 64 is opposite to the pressing portion 93 with respect to the center O of the second optical fiber 3 of the receptacle-side optical connector 65. 9 is slightly shifted to the upper side in FIG.

  Note that the method of assembling the plug-side optical connector 64 and the receptacle-side optical connector 65 in the optical connector 1B according to the third embodiment is substantially the same as that in the first embodiment, and thus the description thereof is omitted.

  Next, a case where the plug side optical connector 64 and the receptacle side optical connector 65 are connected will be described.

  FIG. 11A to FIG. 11C are diagrams showing a connection state of the plug-side optical connector and the receptacle-side optical connector, and are sectional views, respectively. 12 (a) and 12 (b) are diagrams for explaining the holding state of the optical fiber. FIG. 12 (a) is a cross-sectional view taken along line FF in FIG. 11 (b), and FIG. It is GG sectional drawing in FIG.11 (c).

  In order to connect the plug-side optical connector 64 and the receptacle-side optical connector 65, the plug-side optical connector 64 and the receptacle-side optical connector 65 are brought close to each other.

  Then, as shown in FIG. 11A, the pressing portion 93 of the receptacle-side optical connector 65 enters the pressing portion insertion space 79 of the plug-side optical connector 64, and the plug-side insertion into the guide portion insertion space 95 of the receptacle-side optical connector 65 is performed. The guide part 77 of the optical connector 64 enters.

  At this time, the position of the center O of the second optical fiber 3 of the receptacle-side optical connector 65 is shifted to the opposite side of the guide portion 77 with respect to the center O of the first optical fiber 2 of the plug-side optical connector 64, The position of the center O of the first optical fiber 2 of the plug-side optical connector 64 is shifted to the opposite side of the pressing portion 93 with respect to the center O of the second optical fiber 3 of the receptacle-side optical connector 65. Therefore, damage due to contact of the end surface of the core / cladding portion 6 of the second optical fiber 3 with the guide portion 77 of the plug-side optical connector 64 is prevented, and the end surface of the core / cladding portion 6 of the first optical fiber 2 is prevented. Is prevented from coming into contact with the pressing portion 93 of the receptacle-side optical connector 65.

  Further, when the plug-side optical connector 64 and the receptacle-side optical connector 65 approach each other, as shown in FIG. 11B, the end surface of the core / cladding portion 6 of the first optical fiber 2 and the second optical fiber 3 The end surfaces of the core / cladding portion 6 are abutted against each other. At this time, the position of the center O of the second optical fiber 3 of the receptacle-side optical connector 65 is shifted to the opposite side of the guide portion 77 with respect to the center O of the first optical fiber 2 of the plug-side optical connector 64. As shown in FIG. 12A, the core / cladding portion 6 of the second optical fiber 3 is separated from the guide portion 77 of the plug-side optical connector 64. Similarly, the position of the center O of the first optical fiber 2 of the plug-side optical connector 64 is shifted to the opposite side of the pressing portion 93 with respect to the center O of the second optical fiber 3 of the receptacle-side optical connector 65. The core / cladding portion 6 of the first optical fiber 2 is in a state of being separated from the pressing portion 93 of the receptacle-side optical connector 65.

  In this state, when the plug-side optical connector 4 and the receptacle-side optical connector 5 further approach each other, as shown in FIG. 11C, the pressing guide surface 98 of the pressing portion 93 of the receptacle-side optical connector 65 is connected to the plug side. The slidable contact is made with the pressing guide surface 83 of the pressing portion 78 of the optical connector 64. As a result, the holding portion 93 of the receptacle-side optical connector 65 is displaced to the guide portion 77 side which is the holding portion 94 side due to the elastic deformation of the thin portion 97.

  Thereby, as shown in FIG. 12B, the core / cladding portion 6 of the second optical fiber 3 is pressed against the plug-side V groove 80 of the guide portion 77, and the plug-side V groove 80 and the holding portion of the guide portion 77 are pressed. The core / cladding portion 6 of the second optical fiber 3 is sandwiched between the receptacle-side V-grooves 93. Similarly, the core / cladding portion 6 of the first optical fiber 2 is pressed by the receptacle-side V groove 96 of the holding portion 93, and the plug-side V groove 80 of the guide portion 77 and the receptacle-side V groove 96 of the holding portion 93 The core / cladding portion 6 of one optical fiber 2 is sandwiched. Accordingly, the end portions of the core / cladding portion 6 of the first optical fiber 2 and the core / cladding portion 6 of the second optical fiber 3 that are abutted against each other are the plug-side V groove 80 of the guide portion 77 and the receptacle of the holding portion 93. It is pressed by the side V groove 96 and securely held.

  The plug-side V-groove 80 and the receptacle-side V-groove 96 are in contact with the wall surfaces 80a, 96a of the plug-side V-groove 80 and the receptacle-side V-groove 96 when the pressing portion 93 is elastically deformed toward the guide portion 77. The diameter of the circle is preferably formed so as to be smaller by about 1% to 5% than the outer diameter of the core / cladding portion 6 of the first optical fiber 2 and the second optical fiber 3. In this way, the tip of the core / cladding portion 6 of the first optical fiber 2 and the second optical fiber 3 can be securely held without rattling, and even if an external force such as an impact acts, The tips of the core / cladding portions 6 of the first optical fiber 2 and the second optical fiber 3 can be sufficiently retained.

  As described above, when the plug-side optical connector 64 and the receptacle-side optical connector 65 are completely fitted, the first housing 69 and the first housing 69 are locked by the locking mechanisms (not shown) provided in the first housing 69 and the second housing 88. The second housing 88 is engaged with each other and maintained in a fitted state.

  In the optical connector 1 </ b> B of the third embodiment, when the plug-side optical connector 64 and the receptacle-side optical connector 65 are fitted, the first optical fiber 2 of the plug-side optical connector 64 is rearward with respect to the first housing 69. Is pushed into. When the first optical fiber 2 is pushed backward with respect to the first housing 69, the coil spring 53 is compressed and deformed in the longitudinal direction, and the extra length portion of the first optical fiber 2 is the first housing rear portion 74 of the first housing 69. It is drawn to the side. At this time, the first optical fiber 2 is urged and pressed against the second optical fiber 3 by the reaction force of the compressive deformation formed by the elastic force of the coil spring 53. As a result, the core / cladding portion 6 of the first optical fiber 2 and the core / cladding portion 6 of the second optical fiber 3 are maintained in contact with each other.

  Thus, also in the case of the optical connector 1B according to the third embodiment, when the plug-side optical connector 64 and the receptacle-side optical connector 65 are fitted, the coil spring 53 is compressed and deformed, so Long absorption and pressing of the tips of the first optical fiber 2 and the second optical fiber 3 can be realized. For this reason, the bending of the 1st optical fiber 2 and the 2nd optical fiber 3 at the time of a connection can be prevented. Therefore, even if glass optical fibers are used as the first optical fiber 2 and the second optical fiber 3, there is no risk of breakage, and even if a plastic optical fiber is used, the pressing force cannot be secured due to plastic deformation. Can be eliminated.

  Further, since the first optical fiber 2 is displaced without being bent, the first optical fiber 2 is not plastically deformed and the tip position is not drawn from a predetermined position even if the connection is released. For this reason, even if the plug-side optical connector 64 and the receptacle-side optical connector 65 are repeatedly attached and detached, it is possible to prevent a problem that the tips of the first optical fiber 2 and the second optical fiber 3 are not in contact with each other.

  In addition, a space for bending the first optical fiber 2 is not necessary, and therefore the size of the first housing 69 in the longitudinal direction can be reduced.

  Moreover, since no adhesive is used to fix the first optical fiber 2 and the second optical fiber 3, assembly is easy and high reliability can be ensured.

  In particular, according to the third embodiment, when the plug-side optical connector 64 and the receptacle-side optical connector 65 are fitted, the distal ends of the first optical fiber 2 and the second optical fiber 3 are plugged into the plug-side V-groove of the guide portion 77. 80 and the receptacle-side V groove 96 of the holding portion 93 are aligned and held. Therefore, the axial shift between the first optical fiber 2 and the second optical fiber 3 can be suppressed, and a low-loss optical connection can be realized.

  In addition, since the plug-side V-groove 80 and the receptacle-side V-groove 96 have the function of holding the tip portions of the first optical fiber 2 and the second optical fiber 3, there is a risk that the optical connection loss may increase due to vibration or impact. Can be eliminated.

  In addition, since the plug-side V-groove 80 and the receptacle-side V-groove 96 are not required to have high accuracy, fabrication can be facilitated and yield can be improved.

  In addition, since the plug-side V-groove 80 can be integrally formed with the first housing 69 and the receptacle-side V-groove 96 can be integrally formed with the second housing 88, the component cost of the optical connector 1B can be reduced.

  In the third embodiment, the plug-side V groove 80 is formed in the guide portion 77 as the groove portion for holding the first optical fiber 2 and the second optical fiber 3, and the plug-side V groove 96 is formed in the holding portion 93. However, the groove portion that holds the first optical fiber 2 and the second optical fiber 3 is not limited to the V groove as long as the first optical fiber 2 and the second optical fiber 3 can be held. As a groove part holding the 1st optical fiber 2 and the 2nd optical fiber 3, a U groove or a concave groove may be sufficient, for example.

  Further, in the third embodiment, when the plug-side optical connector 64 and the receptacle-side optical connector 65 are fitted, the holding portion 93 of the receptacle-side optical connector 65 is elastically deformed to cause the plug-side V groove 80 and the receptacle-side V groove. 96, but the guide portion 77 of the plug-side optical connector 64 may be elastically deformed so that the plug-side V groove 80 and the receptacle-side V groove 96 approach each other. Both the guide portion 77 and the holding portion 93 of the receptacle-side optical connector 65 may be elastically deformed so that the plug-side V-groove 80 and the receptacle-side V-groove 96 approach each other.

  In the third embodiment, the first optical fiber 2 of the plug-side optical connector 64 is pressed and held by the coil spring 53, but the second optical fiber 3 of the receptacle-side optical connector 65 is pressed and held by the coil spring 53. Alternatively, both the first optical fiber 2 of the plug-side optical connector 64 and the second optical fiber 3 of the receptacle-side optical connector 65 may be pressed and held by the coil spring 53.

  In the first to third embodiments, the coil spring 53 is fixedly attached to the first optical fiber 2 or the second optical fiber 3 by caulking the tip of the coil spring 53. The first optical fiber 2 or the second optical fiber 3 may be attached by other attachment structures.

  Here, another structure for attaching the coil spring 53 to the first optical fiber 2 or the second optical fiber 3 will be described by taking as an example the case of assembling the receptacle-side optical connector 5 in the first and second embodiments.

  FIGS. 13A to 13D are views for explaining how to assemble the receptacle-side optical connector with the coil spring attached in the mounting structure according to the modification, and are respectively sectional views.

  When the coating layer 7 of the second optical fiber 3 that has been passed through the coil spring 53 in advance is peeled to a predetermined length to expose the core / cladding portion 6, and the end surface of the core / cladding portion 6 is processed to be smooth, FIG. As shown to (a), the 2nd optical fiber 3 is inserted in the flange 100 formed in cyclic | annular form.

  Next, as shown in FIG. 13 (b), the flange 100 is caulked, and the flange 100 is fixed to the vicinity of the end of the coating layer 7 of the second optical fiber 3.

  And as shown in FIG.13 (c), the 2nd optical fiber 3 is inserted in the through-hole 51 of the 2nd housing 38 from the back side of the 2nd housing 38, and the coil spring 53 previously passed through is 2nd. It moves to the front end side of the optical fiber 3 and is accommodated in the spring accommodating space 43, and then a spring stopper 55 is attached from the rear end of the second housing 38.

  In this way, as shown in FIG. 13D, the receptacle-side optical connector 5 is assembled, and the coil spring 53 is pushed forward by the spring stopper 55 and is housed in the spring housing space 43 in a slightly compressed state. To be held. Therefore, the flange 100 fixed by crimping is urged forward by the coil spring 53, whereby the second optical fiber 3 is also held in the second housing 38 in a state of being urged forward.

  As described above, when the flange 100 is used, the coil spring 53 can be locked to the second optical fiber 3 to apply an elastic force without processing the coil spring 53.

  Moreover, in the said 1st-3rd embodiment, although the coil spring 53 was used as an elastic member which gives elastic force to the 1st optical fiber 2 and / or the 2nd optical fiber 3, as an elastic member, a coil spring is used. For example, a leaf spring or rubber may be used.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably. In addition, the material, shape, dimensions, number, arrangement location, and the like of each component in the above-described embodiment are arbitrary and are not limited as long as the present invention can be achieved.

1, 1A, 1B Optical connector 2 First optical fiber (optical fiber)
3 Second optical fiber (optical fiber)
9,69 First housing (housing)
38,88 Second housing (housing)
53 Coil spring (elastic member)
55 Spring stopper 63 Notch 100 Flange

Claims (4)

A first housing, a first optical fiber accommodated in the first housing, a second housing engaged with the first housing, and a second optical fiber accommodated in the second housing,
As the first housing and the second housing are engaged with each other, the end face of the first optical fiber and the end face of the second optical fiber are brought into contact with each other so that optical connection is performed. And
An elastic member held by one of the first housing and the second housing;
The one housing has a through-hole inserted through the optical fiber accommodated in the one housing, and holds the optical fiber movably along the axial direction.
The elastic member is fixed to the optical fiber, and is held by the one housing so as to urge the optical fiber along the axial direction in a state where the tip of the optical fiber protrudes from the through hole,
The optical connector is displaced against the urging force of the elastic member by being pushed in a state in which the optical fiber is abutted against the other optical fiber. The optical connector according to claim 1,
An optical connector, wherein a displacement dimension in which the optical fiber is displaced is smaller than a deformable dimension of the elastic member. The optical connector according to claim 1 or 2,
The elastic member has a front end locked to the optical fiber,
Said one housing has a spring stop which latches the rear-end part of said elastic member. The optical connector characterized by the above-mentioned. The optical connector according to claim 3,
The one housing includes a housing main body and the spring stopper, and the spring stopper is detachable from the housing main body.
The optical connector is characterized in that the spring stopper has a cutout portion through which the optical fiber is inserted, and the cutout portion is attached to the housing body while being inserted through the optical fiber.

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