JPH0812309B2 - Optical connector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to an optical connector for detachably connecting an optical cord, and in particular, secures a coupling force against a pulling force at the time of connection.

<Prior Art> When a plurality of optical cords each having an optical fiber incorporated therein are detachably coupled, in general, an optical plug is attached to the tip end of the optical cord, and the optical plug is used to connect the optical cords via a plug adapter. An optical connector that connects the cords to each other is adopted. As a high-performance optical connector in which the operation of attaching / detaching the optical plug to / from such a plug adapter is easy and the coupling loss is small, for example, an SC type optical connector presented in JP-A-63-239407 (JIS Industrial Standard "F04
Single-core optical fiber connector [S5973-1993] ”) is known.

As shown in FIG. 7 showing the schematic structure of the SC type optical connector, the plug adapters 103 to which the optical plugs 102 formed at the tip of the optical cord 101 are detachably mounted are
Adapter housing 1 with elastic arm 104 protruding inside
05 has a locking claw 1 at the end of this elastic arm 104.
06 and a protrusion 107 for removal are formed. On the other hand, the optical plug 102 includes a plug housing 110 having a ferrule 108 and an engaging projection 109, and the plug housing 110.
And a knob block 112 that is slidably mounted on the same and that has a release projection 111 formed thereon.

Therefore, when the optical plug 102 is attached to the plug adapter 103, the elastic arm 1 protruding from the plug adapter 103
The locking claw 106 of 04 is engaged with the engaging projection 109 formed on the plug housing 110 of the optical plug 102, and the plug adapter 103
And the optical plug 102 are integrally coupled. Conversely, when removing the optical plug 102 from the plug adapter 103,
By pulling out the knob block 112 attached to the optical plug 102 from the plug adapter 103, the knob block 112
The release projection 111 formed on the abutment abuts on the removal projection 107 to push up the elastic arm 104, and the engagement between the locking claw 106 and the engagement projection 109 is released, so that the plug adapter 103 and the optical plug 102 are released. Is removed.

<Problems to be Solved by the Invention> As shown in FIG. 8 which schematically shows the structure of a conventional engaging portion in an SC type optical connector, the optical plug 102 and the plug adapter 103 are engaged with each other by the plug adapter 103. Locking claw 106 of the elastic arm 104 protruding from the adapter housing 105 of
And an engaging projection 109 formed at the tip of the plug housing 110 of the optical plug 102. here,
When the optical plug 102 is pulled to the right in the figure, the force is transmitted to the locking claw 106 via the engaging projection 109, but the point of action thereof and the base portion of the elastic arm 104 deviate by d. A counterclockwise bending moment M about the base of the elastic arm 104 is generated.

Therefore, when the pulling force that separates the optical plug 102 and the plug adapter 103 becomes large, the tip side of the elastic arm 104 gradually warps upward, and the engagement surface of the locking claw 106 slides on the engagement surface of the engagement projection 109. As a result, the engaged state may be released, and the optical plug 102 may come off from the plug adapter 103.

In order to solve such a problem, for example, in the above-mentioned "optical connector" of JP-A-63-239407, the locking claw 10
The coefficient of friction between the engagement surface of 6 and the engagement surface of the engagement projection 109 is made sufficiently large, or the pulling direction of the optical plug 102 and the locking claw 106.
It is proposed that the angle between the engagement projection 109 and the engagement surface is acute.

However, if the optical connector is small, the locking claw 10
Since the dimensions and shape of 6 and the engaging projections 109 are also small, it is difficult to generate sufficient frictional force on the engaging surfaces of the locking claws 106 and the engaging projections 109, and the pulling direction of the optical plug 102 is different. When the angle formed between the engaging claw 106 and the engaging projection 109 with the engaging surface is made acute, stress concentrates on the base portions of the engaging claw 106 and the engaging projection 109, and they are damaged. In any of the cases, it is difficult to solve the problem that the optical plug 102 comes off from the plug adapter 103.

<Object of the Invention> An object of the present invention is to provide an optical connector in which the connection between the optical plug and the plug adapter is prevented from being disconnected even when a large tensile force is applied to the optical cord.

<Means for Solving the Problems> An optical connector according to the present invention is an optical connector including an optical plug formed at a tip end portion of an optical cord and a plug adapter into which the optical plug is detachably inserted. An engaging projection that is provided on the tip of the optical plug and has an engagement surface facing the base end side of the optical plug; and a projection on the tip of the plug adapter that covers the tip of the optical plug. A claw holder to be covered, an elastically deformable elastic arm projecting from the tip of the claw holder toward the engaging projection side so as to be located between the claw holder and the plug, and this elastic arm. Locking claws protruding from the tip end, facing the plug adapter side, and having an engaging surface capable of engaging with the engaging projections, and disengagement formed on the elastic arm with this locking cold Abutment part for A knob block for engaging and disengaging, which is mounted on the optical plug so as to be slidable with respect to the direction of inserting and removing the plug with respect to the plug adapter, and the engaging projection and the locking formed at the tip of the knob block. It is characterized in that it is provided with a protrusion for releasing the engagement that abuts on the abutting portion so as to release the engagement with the claw and elastically deforms the elastic arm.

Further, in the above optical connector, when the optical connector is mounted on the plug adapter, the engaging projection side contact surface of the elastic arm provided in the adapter and the outer peripheral contact surface of the optical plug housing are watertight. You may make it contact | abut in a state.

<Operation> When the optical plug is inserted into the plug adapter, the engaging projection of the optical plug comes into contact with the locking claw of the elastic arm protruding from the claw holder of the plug adapter, and the elastic arm integrated with the claw holder elastically deforms. The engaging claw rides on the engaging projection, and the engaging surface of the engaging projection and the engaging surface of the engaging claw enter the engaged state.

When the optical cord on the optical plug side is pulled here, the force is transmitted to the locking claw via the engagement projection, but since the point of action thereof and the base part of the elastic arm with respect to the claw holder of the plug adapter are displaced, A bending moment is generated in the elastic arm such that the tip side approaches the optical plug side around the root. As a result, when a pulling force that separates the optical plug and the plug adapter acts on the optical cord, the tip end side of the elastic arm falls to the optical plug side, and the engagement surface of the locking claw bites the engagement surface of the engagement projection. Accordingly, these engaged states are reliably maintained.

On the other hand, when removing the optical plug from the plug adapter, grasp the knob block and pull it so that the optical plug comes out of the plug adapter, and the protrusion for releasing the knob block engagement is formed on the elastic arm of the plug adapter. Push up the abutting part for releasing the engagement, the elastic arm warps so as to disengage from the engaging claw of the engaging projection, and pull the optical cord in this state to pull out the optical plug from the plug adapter. Removed.

<Embodiment> FIG. 1 shows a schematic structure of an embodiment in which the optical connector according to the present invention is applied to a push-pull type. Further, the front shape and the plan shape of the optical plug are shown in FIGS. 2 and 3, and the left side shape of FIG. 1 is shown in FIG.

That is, in the plug housing 15 of the optical plug 14 having the ferrule 13 tightly fitted to the cylindrical sleeve 12 fitted to the central portion of the plug adapter 11, the plug housing 15 has a rectangular tubular knob block. 16 is fitted, and the knob block 16 is slidable with respect to the plug housing 15 in a certain range in the left-right direction in FIG. Also, the plug housing of this optical plug 14 in which the optical cord 17 extends from the rear end.
A pair of upper and lower engaging projections 18 are provided on the tip of the projection 15. Further, projections 21 for disengagement having an inclined surface 19 for insertion and an inclined surface 20 for removal are formed at the tip of the knob block 16 so as to be located on both sides of the engaging projections 18.

The plug adapter 11 having the coupling flange 22 formed therein has a rectangular tube-shaped claw holder that covers the tip side of the optical plug 14.
23 are provided. Inside the claw holder 23, a pair of upper and lower elastic arms 24 extending from the tip end side to the base end side of the claw holder 23 are projectingly provided so as to sandwich the optical plug 14, and these tip ends of the elastic arms 24 are provided. Are provided with locking claws 25 that can be engaged with the engaging projections 18 of the optical plug 14, respectively.
The engagement surface 26 of the locking claw 25 faces the direction (left direction in FIG. 1) for coupling the optical plug 14 with the plug adapter 11,
The engagement surface 27 of the engagement projection 18 is set so as to face the direction in which the optical cord 17 is pulled out (rightward in FIG. 1).
Further, the end of the elastic arm 24 corresponding to the engagement releasing projection 21 can come into contact with the insertion slope 19 and the removal inclination 20 of the engagement release projection 21. The engagement releasing contact portions 28 are formed so as to be located on both sides of the locking claw 25, respectively.

Therefore, as shown in FIG. 5 schematically showing the structure of the engaging portion according to the present embodiment, when the pulling force acts on the optical cord 17 and the pulling force in the right direction in the figure is applied to the optical plug 14. , Its force is transmitted to the locking claw 25 via the engagement projection 18, but its point of action and the elastic arm 24 protruding from the claw holder 23.
The elastic arm 24
Is a counterclockwise bending moment M around its root.
Occurs.

As a result, when the pulling force that separates the optical plug 14 and the plug adapter 11 from each other becomes large, the tip end side of the elastic arm 24 gradually falls downward, and the engaging surface 26 of the engaging claw 25 and the engaging surface of the engaging projection 18 are engaged. 27 and 27 are engaged, and the engagement state between the plug adapter 11 and the optical plug 14 is maintained as it is.

In this way, when the pulling force is applied to the optical cord 17, the locking claw 25 and the engagement projection 18 are more strongly locked, so that the engagement surface 26 of the locking claw 25 and the engagement projection 18 are locked. Engagement surface of
Even if the friction coefficient of 27 is not increased or the angle between the pulling-out direction of the optical cord 17 and the engaging surfaces 26, 27 of the locking claw 25 and the engaging projection 18 is made acute, the coupling strength between these is sufficient. Can be increased.

In particular, when the optical connector is small, it is necessary to make the locking claw 25 and the engagement projection 18 small, but even in such a case, it is necessary to particularly increase the friction coefficient of the engagement surfaces 26 and 27. There is no. Moreover, since it is not necessary to form an acute angle between the pulling-out direction of the optical cord 17 and the engaging surfaces 26 and 27 of the locking claw 25 and the engaging projection 18, the base parts of the locking claw 25 and the engaging projection 18 are formed. It is possible to reduce the concentration of the stress that is applied to the locking claws 25 and the engaging projections 18 and increase the strength of these.

Further, when the optical connector 14 is attached to the plug adapter 11, as shown in FIG. 1, the engaging projection 18 side contact surface 24a of the elastic arm 24 provided in the adapter 11 and the optical plug 14 are connected to each other. If the contact surface 15a on the outer periphery of the plug housing 15 is made to contact in a watertight state, the moment M is further increased.
By the action of, the adhesiveness is improved and the bond strength is strengthened.

By the way, in the case of coupling the optical plug 14 to the above-mentioned plug adapter 11, first, by grasping the knob block 16 and inserting the tip side of the optical plug 14 into the flag adapter 11, it is formed at the tip portion of the knob block 16. The insertion slope 19 of the engagement releasing projection 21 abuts on the engagement releasing abutment portion 28 of the elastic arm 24, and the tip end side of the elastic arm 24 bends back so as to separate from the engagement protrusion 18, and then the removal thereof. Removal slope 20
Is brought into contact with the engagement releasing contact portion 28 of the elastic arm 24, and the knob block 16 is positioned with respect to the plug adapter 11.

In parallel with this operation, with respect to the insertion slope 29 formed on the locking claw 25 on the opposite side of the engagement surface 26, the engagement projection of the optical plug 14
18 pushes up the slope 29 for insertion, the tip end side of the elastic arm 24 bends back so as to separate from the engaging projection 18, and the engaging projection 18 passes through the locking claw 25 of the elastic arm 24, and then the elastic arm 24 automatically. Returns to the original state and the engaging projection 18 and the locking claw
25 and 25 are engaged.

On the other hand, when the optical plug 14 is removed from the plug adapter 11, the knob block 16 is pulled relative to the plug adapter 11 in the right direction in FIG. Then, the optical plug 14 starts moving rightward in FIG. 1 together with the block 16, that is, the block 16. At this time, first, the removal slope 20 of the engagement releasing projection 21 formed at the tip of the knob block 16 contacts the engagement releasing contact portion 28 of the elastic arm 24,
The tip end side of the elastic arm 24 is bent back so as to be separated from the engagement protrusion 18. As a result, the engagement between the engagement projection 18 and the locking claw 25 is released, and in this state, the knob block 16 and the optical plug 14 are removed from the plug adapter 11.

In this embodiment, in order to prevent so-called reverse insertion, a positioning groove 30 is formed on one side wall of the plug adapter 11 and a positioning protrusion 31 corresponding to this is formed on one side wall of the knob block 16. On the other hand, the widths of the engagement releasing projections 21 formed on the knob block 16 and the engagement releasing contact portions 28 formed on the plug adapter 11 are set to different sizes for the left and right sides, respectively, and the ferrule is set. The shape is set to be rotationally asymmetric with respect to the center of 13. As a result, the fitting state of the optical plug 14 with respect to the plug adapter 11 is made directional, and when the optical plug 14 is inserted into the plug adapter 11 in the wrong direction, the protrusion 21 for releasing the engagement of the wider one is provided. Is pressed against the base portion of the elastic arm 24, and further insertion cannot be performed.

In the case of the present invention, the distance between the tip surface of the ferrule 13 of the optical plug 14 and the engagement surface 27 of the engagement projection 18 can be made smaller than that of the conventional one shown in FIGS. It is possible to set the engagement position between the combination projection 18 and the locking claw 25 of the elastic arm 24 on the tip side of the optical plug 14. Therefore, the present invention is also suitable for a so-called plug-in type optical connector.

Therefore, FIG. 6 shows a partially cutaway sectional structure of an embodiment in which the optical connector of the present invention is applied to the back panel side of a plug-in type optical connector.

That is, the back panel 51 has a main back panel housing 52 having substantially the same structure as the plug adapter 11 shown in FIGS. 1 and 4 described above, and faces the main back panel housing 52 with the back panel 51 interposed therebetween. The sub back panel housing 53 is attached. The main back panel housing 52 shown in FIGS.
An optical plug 54 having the same structure as the optical plug 14 shown in the figure is detachably attached.

Therefore, the sub-back panel housing 53 and the back panel 51 are respectively formed with through holes 55, 56 through which the optical plug 54 penetrates, and the elastic arm 57 is an end portion of the main back panel housing 52 on the back panel 51 side. From the right in the figure, the locking claw 58 is projected to the right, and the plug housing 59
The main back panel housing 52 and the optical plug 54 are coupled to each other by engaging with the engaging projection 60 provided at the tip of the.

Also in this embodiment, when the optical cord 61 extending from the rear end of the optical plug 54 is pulled to the left in the drawing, the pulling force locks the elastic arm 57 via the engaging projection 60 of the plug housing 59. Acts on the pawl 58 and engages the pawl 58 as described above.
The engagement projection 60 is engaged with the main back panel housing 52 and the optical plug 54 is maintained.

The structure on the package side may be a well-known structure, or the structure of the embodiment shown in FIG. 1 may be modified and incorporated into this embodiment shown in FIG. It is also possible. Further, when removing the optical plug 54 from the main back panel housing 52, it is easy to pull the optical plug 54 out of the main back panel housing 52 by pulling the knob block 62 to the left side in the figure as in the above-described embodiment. Can be removed.

As described above, in the above-described embodiments, the present invention is applied to the SC type optical connector and the plug-in type optical connector, but it is naturally possible to apply the present invention to optical connectors having structures other than these.

<Effects of the Invention> According to the optical connector of the present invention, even if a large pulling force is applied to the optical cord, the tip side of the elastic arm of the plug adapter tends to elastically deform so as to fall toward the engaging projection side of the optical plug. However, there is no change that deteriorates the engagement state between the engagement surface of the locking claw of the elastic arm and the engagement surface of the engagement projection of the optical plug. Further, when removing the optical plug from the plug adapter, it is only necessary to move the knob block relative to the optical plug, so that an optical connector having high tensile strength and good operability can be realized.

[Brief description of drawings]

FIG. 1 is a sectional view showing a partially broken state of an embodiment in which the present invention is applied to a push-pull type optical connector, FIG. 2 is a front view of the optical plug portion, and FIG. 3 is a plan view thereof. ,
FIG. 4 is a left side view of FIG. 2, FIG. 5 is a principle view showing an engaging concept of an engaging portion of the optical connector according to this embodiment, and FIG. 6 is an application of the present invention to a plug-in type optical connector. FIG. 7 is a cross-sectional view showing another embodiment of the present invention in a partially broken state, FIG. 7 is a perspective view showing a conventional push-pull type optical connector in a partially broken state, and FIG. It is a principle diagram showing an engagement concept. In the figure, 11 is a plug adapter, 13 is a ferrule, 14 and 54 are optical plugs, 16 and 62 are knob blocks, and 17 and 61.
Is an optical code, 18 and 60 are engaging projections, 21 is a releasing projection, 23 is a claw holder, 24 and 57 are elastic arms, 25 and 58 are locking claws, 26 and 27 are engaging surfaces, and 28 is a An abutting portion for releasing, 29 is an inclined surface for insertion, 51 is a back panel, and 52 is a main back panel housing.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-63-239407 (JP, A) JP-A-63-193110 (JP, A) Actually opened 62-176807 (JP, U) Actually opened 57- 195113 (JP, U)

Claims (2)

[Claims] 1. An optical connector comprising an optical plug formed at the end of an optical cord and a plug adapter into which the optical plug is detachably inserted, the optical connector being provided so as to project from the end of the optical plug. An engagement protrusion having an engagement surface facing the base end side of the optical plug, a claw holder projecting from the tip of the plug adapter and covering the tip side of the optical plug, the claw holder and the light An elastically deformable elastic arm projecting from the tip of the claw holder toward the engaging projection so as to be located between the plug holder, and the plug adapter projecting at the tip of the elastic arm. A locking claw that faces toward the side and has an engagement surface that can be engaged with the engagement projection; an engagement releasing contact part that is formed on the elastic arm together with the locking claw; and the plug adapter Against the optical plastic And a knob block for disengagement, which is mounted on the optical plug so as to be slidable in the inserting / removing direction, and engagement between the engaging projection and the engaging claw formed at the tip of the knob block. An optical connector, comprising: an engagement releasing projection that abuts against the abutting portion to be released and elastically deforms the elastic arm. 2. The optical connector according to claim 1, wherein when the optical connector is mounted on the plug adapter, an engaging surface of the elastic arm provided in the adapter for engaging projections and a plug housing of the optical plug. An optical connector, characterized in that the contact surface of the outer periphery of the connector contacts in a watertight state.