JPH09211262A - Plug of optical connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a plug from coming out owing to a mistouch without decreasing the operability of the plug attachment and detachment of the optical connector. SOLUTION: Projections are provided at the winding start and end parts of a coil spring 7 which energizes a coupling 6 forward to a barrel 4; and the winding start projection is inserted into a groove 6a formed in the coupling 6 and the winding end projection is inserted into a groove 4b formed in the barrel 4, which is energized clockwise. The coupling is further provided with a J groove 6b and a cut 6c, an end bell 10 is provided with a rotation stopper 10a, and the notch 6c is engaged abutting against the rotation stopper 10a. Consequently, the plug can be disengaged backward for the first time on condition that the coupling 6 is rotated temporarily counterclockwise and the J groove 6b comes to the position of the rotation stopper 10a.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of optical connectors for connecting optical fibers.

[0002]

2. Description of the Related Art In general connection of optical fibers, the optical connection is maintained by fixing the optical fiber at the center of the ferrule, inserting this into an alignment sleeve, and abutting the end faces of the ferrules by pressing a spring. . Therefore, a force is always applied to the coupling portion of the optical connector including them in the detaching direction, which has a structure peculiar to the optical connector. On the other hand, as a mating structure for connecting and disconnecting the optical connector, a push
The lock and pull out methods are widely used.

FIG. 5 is a partially cutaway sectional view showing a receptacle 2 of a conventional optical connector and a plug 1b opposed to each other. The plug 1b is provided with a cylindrical barrel 4 containing a ferrule 11, a cylindrical end bell 10 connected and fixed to the rear end thereof, and a concentric cylinder provided on the outside thereof, and moves relative to the barrel 4 in the axial direction. A coupling 15 which is possible and a gap between the coupling 15 and the barrel 4 is formed in a concentric coil shape, and the rear side is supported by the ring 8 and the coupling 15 is moved forward with respect to the barrel 4 via the front slide ring 5. It has a coil spring 12 for urging it toward the receptacle 2).

The receptacle 2 has a cylindrical shell 16 that fits in the gap between the barrel 4 of the plug 1b and the coupling 15, and this is a shape that protects the ferrule 11. The shell 16 is provided with engaging balls 3 at a plurality of locations along its circumference.
Is movable in the radial direction of the shell 16, and a part of the spherical body is held so as to project to the outside of the shell 16 or to the inner wall side by an external force. The barrel 4 is provided with a groove 4a into which the protruding portion of the engaging ball 3 fits. When the receptacle 2 and the plug 1b are fitted to each other, the end faces of the ferrules 11 are brought into contact with each other by the pressing of the springs 13 located at the rear of the ferrules 11 to obtain an optical connection.

Hereinafter, the receptacle 2 will be described with reference to FIG.
The process of connecting the plug 1b and the plug 1b will be described. (A) is a partial cross-sectional view of the state where they are still facing each other. Next, when the plug 1b is inserted as shown in (b), the engagement ball 3 is pushed up by the inclined portion slightly rearward from the tip of the barrel 4, and the state continues in the flat portion. Then, a part of the engagement ball 3 projects to the outside of the shell 16 and abuts on the tip of the slide ring 5 that has moved forward to prevent the slide ring 5 from moving forward. Still, when the coupling 15 is further pushed forward, the coil spring 12 is compressed and the barrel 4 moves forward while the slide ring 5 remains stopped. And
When the groove 4a of the barrel 4 has just come under the engaging ball 3, the engaging ball 3 is pushed down by the inclined portion of the tip of the slide ring 5 and fits into the groove 4a.

FIG. 3C is a diagram showing a state at the moment when the engaging ball 3 falls. If the engaging ball 3 falls down, there is nothing to prevent the slide ring 5 from advancing. Therefore, the repulsive force of the coil spring 12 that has been compressed pushes it forward to the locking portion inside the coupling 15. Abut and stop. At this time, a clicking sound is heard.

(D) shows this state. In this state, the lower surface of the slide ring 5 is now the engagement ball 3
Is prevented from going up. Therefore, the engagement ball 3
Is partially fitted in the groove 4a of the barrel 4, and the barrel 4 is in a so-called locked state in which it cannot be retracted. Therefore, the click sound described above is a sound indicating that the receptacle 2 and the plug 1b are fitted and locked. That is, (d) is a diagram showing the fitting lock state.

Next, the process of releasing from the fitting lock state will be described. When disengaged, the coupling 15 is pulled rearward against the biasing force of the coil spring 12. And FIG.
When the slide ring 5 is retracted to the state of (a), the slide ring 5 disappears above the engagement ball 3, so that the engagement ball 3 can move upward. By the way, since the barrel 4 is also pulled backward by the repulsive force of the coil spring 12, the groove 4
The engaging ball 3 is pushed upward by the inclined portion of a so that the locked state is released, and the barrel 4 is retracted until its ring 8 comes into contact with the stop ring 9 provided inside the coupling 15. FIG. 7B shows a state in the middle of backward movement. When the ring 8 comes into contact with the stop ring 9, a clicking sound is generated, indicating that the barrel 4 has returned to the normal position in the disengaged state. FIG. 7C is a diagram showing a state in which the robot is completely separated after that.

As described above, the conventional connector has the coupling 15 when it is fitted (joined) and when it is detached.
On the other hand, it is performed by applying a constant force in the axial direction. In other words, push lock for easy attachment and detachment,
It is a pull-out method.

[0010]

By the way, in the optical connector, in order to reduce light loss at the time of fitting, the end faces of the ferrule of the receptacle and the plug are pressed by the springs 13 at the rear of each. As a reaction, a force is applied to the receptacle and the plug in the direction of separating them. Therefore, if a force is erroneously applied to the coupling and the coupling retracts to the state of FIG. 7A, there is a problem that the connector is likely to be detached due to the repulsive force between the ferrules.

In view of the above-mentioned problems of the conventional optical connector, an object of the present invention is to prevent the coupling from retreating unless it is rotated by a certain angle, so that the operability is not deteriorated and the coupling is prevented from being erroneously operated. An object of the present invention is to provide a plug of an optical connector that is hardly detached.

[0012]

The present invention has the following means in order to achieve the above object. That is, the plug of the optical connector of the present invention comprises a cylindrical barrel containing a ferrule inside, a cylindrical end bell connected and fixed to the rear end of the barrel, and a concentric cylinder provided on the outside thereof in the axial direction with respect to the barrel. Has a coupling movable relative to each other and a coil spring that is formed in a concentric coil shape in a gap between the coupling and the barrel and biases the coupling forward with respect to the barrel. A plug for an optical connector, in which the coupling has to be pulled backward against the biasing force of the coil spring when it is disengaged, and the coil spring also biases the coupling in the axial rotation direction with respect to the barrel. The end bell is provided with a rotation stopper that locks the rotation of the coupling and the backward movement of the coupling due to this rotation bias. First abutting against the detent is biased to the coil spring
A contacting part of the second contacting part, which is stopped by contacting the rotation stopper even if the coupling is pulled rearward in the contacting state, and the second contacting part from the second contacting part in the rotation urging direction. A groove for avoiding the rotation stop is provided at a position separated by a rotation angle so as to be pulled backward without being blocked by the rotation stop.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The plug of the present invention is similar to the conventional one in that it is of a push-lock type when fitted, but at the time of disengagement, the coupling is first rotated by a certain angle and then rearward. By adopting a double-action system, such as pulling downward (that is, pulling backward only after rotating), it is intended to prevent the accidental disengagement without lowering the operability.

Therefore, the coil spring not only urges the coupling forward but also in the rotational direction. The end bell is provided with a rotation stopper for the coupling, and the coupling has a rotation stopper. A first abutting portion that abuts and stops rotation due to rotational bias, and a second abutting portion that abuts against the rotation stopper and is prevented from being pulled backward in the abutting state
Further, there is provided a groove which has a contact portion with which the contact with the rotation stopper can be escaped when rotated. The rotation bias may be clockwise or counterclockwise, and the shape such as the rotation stopper may take various shapes as long as it has the above-described function.

The rotation stop may have a cylindrical or polygonal protrusion structure. Since the first contact portion is a portion where rotation is locked, a protrusion may be provided at the rear of the coupling,
Alternatively, it may be a side portion cut out behind the coupling over a certain rotation angle width.

Further, since the second contact portion is a portion which is prevented from moving rearward in a state where it is not rotated, it may be the rear end edge portion of the coupling or over a certain rotation angle width. It may be a notched edge. The groove is provided in the axial direction from the second contact portion at a position exceeding the expected misoperation rotation angle. If the coupling is thin, it becomes a notch groove, and conversely, if the thickness of the coupling is small and the height of the rotation stopper is small, a concave groove may be provided on the inner wall of the coupling.

The same applies to the first contact portion and the second contact portion. Unless the plug applies external force,
Since the coupling is biased forward with respect to the barrel, it is biased in the direction opposite to the direction in which the second contact portion contacts the rotation stopper, and the first contact portion is biased in rotation. Is in contact with the rotation stopper.

[0018]

Embodiments of the plug of the present invention will be described below with reference to the drawings. FIG. 1 is a partially cutaway sectional view showing a receptacle 2 of an optical connector and an embodiment of a plug of the present invention as opposed to each other. The difference from the conventional FIG. 5 is that the coil spring 12 in FIG. 5 has a simple coil shape, whereas the coil spring 7 in FIG. 1 has an opening angle θ between the winding start and winding end as shown in FIG. And has a protrusion 7a and a protrusion 7b. On the other hand, the coupling 6 is provided with a groove 6a into which the protrusion 7a is inserted and which can be moved back and forth, and the barrel 4 is provided with a groove 4b in the same angular direction as the groove 6a when viewed from the central axis. The projection 7b of the coil spring 7 is inserted in the groove 4b.

Therefore, in the free state, the protrusions 7a and 7b had an opening of the angle θ, but the groove 6a and the groove 4b respectively.
Since the angle is zero when the coil spring 7 is inserted in, the elastic force that tries to return the angle to θ acts on the coil spring 7, and the coupling 6 is attached to the barrel 4 behind the plug 1a (on the right side in the figure). As seen from the above, the rotation is biased clockwise.

The coupling 6 is provided with a J groove 6b in addition to the groove 6a, and further has a notch 6c having a side in the circumferential direction and a side in the axial direction at the opening portion of the J groove 6b. On the other hand, the end bell 10 is provided with a rotation stopper 10a. The axial side of the notch 6c is the rotation stopper 10a.
And the rotational bias of the coil spring 7 is locked here. That is, the side of the notch 6c in the axial direction is the first contact portion referred to in the problem solving means.

Further, even if the coupling 6 is pulled rearward (rightward) in the state shown in FIG. 1, the circumferential side of the notch 6c comes into contact with the rotation stopper 10a and is prevented from pulling backward. . Therefore, the circumferential side of the notch 6c corresponds to the second contact portion referred to in the problem solving means.

With the above-mentioned structure, the coupling 6 is viewed from the rear (right side in the figure) and is rotated counterclockwise against the rotational bias so that the J-groove 6b becomes the rotation stopper 10a. When it comes to the position, the coupling 6 can be pulled backward (to the right in the figure). When the state pulled from the rear side is changed to the free state, the coupling 6 advances forward of the coil spring 7 with respect to the barrel 4 by the urging force, and the notch 6c stops the rotation 1.
When it reaches the position of 0a, it is rotated by the rotation bias, and the axial side of the notch 6c comes into contact with the rotation stopper 10a and stops.

FIG. 3 is a diagram for explaining a process of fitting (coupling) the receptacle 2 and the plug 1a, and a process of fitting (coupling) the conventional receptacle 2 and the plug 1b (FIG. 6 and its description). The description is omitted because it is exactly the same. FIG.
FIG. 6 is a diagram illustrating a process of leaving. (A) shows a state in which the coupling 6 is rotated counterclockwise (as viewed from the rear) against the rotational bias to bring the J groove 6b to the position of the rotation stopper 10a. In this state, the coupling 6 can be pulled backward (to the right in the figure), and the plug 1a is then disengaged in the same manner as described with reference to FIG. 7 in the description of the conventional technique.

That is, the plug of the optical connector of the present invention is of a push-lock type when it is fitted (coupled) to the receptacle, and when it is detached, it is not a simple pull-out type as in the prior art, but a coupling. It is a double-action system in which it can be pulled backwards after it has been rotated a specified angle. Therefore, it is possible to prevent the plug from being detached due to a erroneous touch without deteriorating the operability.

[0025]

As described above, the plug of the optical connector of the present invention has a structure in which it cannot be pulled out only by pulling it backward, and the coupling can be pulled out after being rotated once by an angle allowing the rotation stopper to escape. Therefore, there is an advantage that the plug does not come off due to a mistaken touch on the coupling. Since the operation of rotating by a predetermined angle does not deteriorate the operability, the advantage of preventing separation can be obtained without decreasing the operability.

[Brief description of drawings]

FIG. 1 is a partially cutaway sectional view showing a receptacle of an optical connector and an embodiment of a plug of the present invention as opposed to each other.

FIG. 2 is a front view and a side view of a coil spring used in the plug of FIG.

FIG. 3 is a partially cutaway sectional view illustrating a process of fitting (coupling) the receptacle and the plug of FIG.

FIG. 4 is a partially cutaway cross-sectional view for explaining a process of separating the fitted (joined) plug from FIG.

FIG. 5 is a partially cutaway sectional view showing a receptacle and a plug of a conventional optical connector as opposed to each other.

6 is a partially cutaway sectional view for explaining a process of fitting (coupling) the receptacle and the plug of FIG.

FIG. 7 is a partially cutaway cross-sectional view for explaining a process of removing the plug that has been fitted (joined) according to FIG.

[Explanation of symbols]

 1a plug 1b plug 2 receptacle 3 engaging ball 4 barrel 4a groove 4b groove 5 slide ring 6 coupling 6a groove 6b J groove 7 coil spring 7a protrusion 7b protrusion 8 ring 9 retaining ring 10 end bell 10a rotation stopper 11 ferrule 12 coil spring 13 Spring 15 Coupling 16 Shell

Claims (1)

[Claims] 1. A cylindrical barrel containing a ferrule inside, a cylindrical end bell connected and fixed to the rear end of the barrel, and a concentric cylindrical outside of these barrels, which are movable in the axial direction relative to the barrel. A coupling and a coil spring that is formed in a concentric coil shape in the gap between the coupling and the barrel and urges the coupling forward with respect to the barrel.When the coupling is disengaged from the fitted receptacle, the coupling is A plug of an optical connector that must be pulled backward against the biasing force of the coil spring, wherein the coil spring also biases the coupling in the axial rotation direction with respect to the barrel, and the end bell is A rotation stopper is provided to lock the rotation of the coupling and the backward movement of the coupling due to this rotation bias, and the coupling is biased by a coil spring. And a second contact portion that abuts against the rotation stopper, and a second contact portion that abuts against the rotation stopper and is blocked even if the coupling is pulled rearward in the corresponding contact state;
Is provided with a groove for avoiding the rotation stop in the axial direction at a position separated from the abutting part of the shaft by an arbitrary rotation angle in the rotation biasing direction so that the rotation stop can be pulled backward without being blocked by the rotation stop. Optical connector plug.