JPH063490B2 - Single-core optical fiber connection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention mainly relates to an optical fiber connecting device in which a single core wire having a diameter of about 1 mm is made of plastic.

(Prior Art) A single-core optical fiber connecting device has a series of insertion holes 2 for inserting two optical fibers 1 and 1 to be connected from each end as shown in FIG. And the optical fibers 1 and 1 are penetrated and held, respectively, and are connected to the outer peripheries of the respective end portions of the connection pipe 3 to remove the coating of the optical fiber in the insertion hole 2 of the connection pipe. It is known that the connector is composed of two connectors 4 that abut the ends of the bare core wire 1a.

(Problems to be Solved by the Invention) The connector 4 includes a cylindrical main body 5 having a through hole along which the optical fiber 1 passes, and a cap nut 6 rotatably held on the outer periphery of the main body 5. Consists of the core 1a, the coating of the tip portion of the core wire 1a is stripped off, and the optical fiber passed through the through hole of the main body is adhered, or the rear portion of the metal main body 5 protruding rearward from the cap nut 6 is pressed and deformed, It is held by crimping it, which is troublesome to hold. Further, in order to connect the connector 4 to the end portion of the connection tube 3, the cap nut 6 must be screwed into the male screw on the outer circumference of the end portion of the connection tube.
Desorption requires time and effort.

Further, it is necessary to accurately determine the length of the core wire 1a protruding from the tip of the tubular body 5, and if the length is short or short, a gap will be created between the tip ends of the core wires of both optical fibers to be connected. A loss occurs in the light to be transmitted. On the contrary, if the amount of protrusion of the core wire 1a is too large, the end faces of both core wires are strongly pressed and broken in the insertion hole of the connecting cylinder. Therefore, it takes time to accurately determine the amount of protrusion of the core wire from the tip of each tubular body.

(Means for Solving the Problems) Therefore, according to the present invention, it is possible to easily hold the optical fiber in the connector without the need for a step such as bonding or crimping, and to detach the connecting tube and the connector with one touch. Therefore, the connector has a U-shaped stopper having two elastic crotch strips that bit the optical fiber, a through hole for passing the optical fiber along the axis, and is orthogonal to the through hole. A body having a lateral hole for accommodating and holding the stopper in a direction orthogonal to the axis, a main body having a pair of elastic arms projecting diametrically opposite from a front end thereof, and a body of the main body A cylindrical portion axially movably fitted and retained on the outer circumference, and a diametrically opposed projecting portion from the front end of the cylindrical portion, which is located within the interval between the elastic arms and has an end of the connecting cylinder at the inner circumference. Has a jaw that holds the outer circumference of the part The cover cylinder is provided with a pair of elastic gripping arms, and the pair of elastic arms and the elastic gripping arms are provided with a cam device that opens the elastic gripping arms radially outward when the elastic arms are bent radially inward. The stopper is provided with an elastic piece movable in the axial direction of the main body, and the elastic piece is locked to the cylindrical portion of the cover cylinder to elastically press the stopper and the main body forward with respect to the cover cylinder. It is characterized by

(Function) To hold the optical fiber, remove the coating on the tip, penetrate the optical fiber into the through hole of the main body, then push the stopper into the lateral hole of the main body, and cover the optical fiber between the elastic crotch of the stopper. While holding the stopper in the lateral hole of the main body while biting the part, and then fitting the cover cylinder to the outside of the main body to fit and hold the cylindrical part of the cover cylinder movably in the axial direction on the outer periphery of the body of the main body, The pair of elastic gripping arms are positioned in the space between the pair of elastic arms of the main body.

As a result, the optical fiber is clamped and held by the two elastic crotch pieces of the stopper housed in the lateral hole of the main body. When the tip of the optical fiber protruding from the front end of the main body is pushed backward, the main body and the stopper in the lateral hole bend the elastic piece of the stopper and retract a little, and when the pushing force is released, the stopper is restored by the elastic piece. And the body moves forward a little.

To connect two optical fibers, push the connector onto the outer circumference of each end of the connecting tube. As a result, the elastic gripping piece of the cover cylinder covers the outer circumference of each end of the connection cylinder, and the jaws at the tip of the inner circumference grip the outer circumference of each end of the connection cylinder, leaving the optical fiber held in each connector bare. The tip of the cored wire projects into a series of insertion holes in the connecting tube.

In this way, the tips of the optical fiber core wires that have entered the insertion hole of the connecting tube from both ends collide with each other in the insertion hole, and the main body and the stoppers in the lateral holes bend the elastic pieces of the stoppers slightly and retreat slightly. The elastic piece pushes against each other by the restoring force and abuts perfectly.

To remove the connector from the connection tube, the pair of elastic arms projecting from the front end of the body of the main body is pressed inward in the radial direction. As a result, the pair of elastic arms are brought into sliding contact with the elastic gripping piece of the cover cylinder by the cam device to push the elastic gripping arms outward in the radial direction. Therefore, when the elastic arm of the main body is pressed inward in the radial direction and a force is applied so as to pull out the connector from the end portion of the connection tube, the connector can be removed from the connection tube.

(Embodiment) In the illustrated embodiment, 11 is a connector of the present invention, the main body described above is 11, the stopper is 21, and the cover cylinder is 31. These are molded plastic articles having elasticity.

The main body 11 has a cylindrical body portion 12, a small-diameter cylinder portion 13 that projects forward from the center of the front end of the body portion 12, and an elastic body having a circular arc-shaped cross section that similarly projects from the outer periphery of the front end of the body portion 12. Arms 14, 14
Have. The tube portion 13 has a thickness that allows it to project from the end into the insertion hole 2 in the connection tube 3, has a protruding length longer than that of the elastic arm 14, and is less than 1/2 of the total length of the insertion hole 2. Short.

A through hole 15 for penetrating the optical fiber has a barrel portion 12 and a tubular portion 13.
A horizontal hole 16 is provided along the center of the through hole 15 for accommodating and holding the stopper 21 therein, and is provided in the body portion 12 by interrupting the through hole 15. In this embodiment, the through hole 15 is provided in the body 12 and has a large diameter hole 15a through which the coating of the optical fiber interrupted by the lateral hole 16 passes, and the through hole 15 is provided in the cylindrical portion 13 to pass the core wire 1a, It consists of a small diameter hole 15b of about 1 mm.

The stopper 21 has a U-shaped cross-section having two elastic crotch pieces 22 and 22, and a non-return pawl 23 is provided at the tip of the outer surface of each crotch piece. Then, slit from the rear end of the bottom where the two crotch pieces 22, 22 are connected.
An elastic piece 25 that is movable in the axial direction is formed after cutting the slit 24, and a protrusion 26 is provided on the outer surface of the bottom of the elastic piece 25.

In the lateral hole 16 in the body part 12 of the main body, the crotch piece 2 of the stopper 21
An intermediate wall 17 that fits shallowly between 2 and 22 is provided between the front and rear wall surfaces of the lateral hole, and a projection 18 is also provided on the rear portion of the outer surface of the intermediate wall 17. The outer surface of the intermediate wall 17 is an arc surface having the same radius of curvature as the outer circumference of the body portion 12.

The tip portion of the optical fiber 1 is slightly longer than the small diameter hole portion 15b of the through hole in the cylindrical portion 13 of the main body, except for the coating, and the large diameter hole portion 15a of the through hole in the body portion 12 is crossed through the horizontal hole 16 to form the cylindrical portion. Through the small-diameter hole 15b, and the tip of the core wire 1a is projected outward from the front end of the tubular portion 13. In this case, the inner surface of the intermediate wall 17 in the lateral hole 16 has the optical fiber inserted from the large diameter hole portion 15a and the small diameter hole portion of the tubular portion 13.
Guide to 15b.

Next, the stopper 21 is pushed into the lateral hole 16. As a result, the elastic crotch piece 22 of the pair of stoppers slides the non-return pawl 23 on the outer surface into sliding contact with the upper and lower walls of the lateral hole and elastically approaches each other while crossing the lateral hole 16 while covering the compressible (rubbery) optical fiber. Hold the part firmly. And if you push the stopper completely into the side hole,
The check claws 23, 23 of both crotch pieces pass through the facing surfaces of the upper and lower walls of the lateral hole to open the patch, and are caught on the edges of the upper and lower walls to prevent the stopper from coming out of the lateral hole in the opposite direction (see FIG. 3). .
Further, further pushing of the stopper is prevented because the inner surface of the bottom portion of the stopper comes into contact with the optical fiber passing through the lateral hole. The tip of each elastic crotch piece 22 of the stopper has a non-return pawl 23.
The radius of curvature is the same as that of the outer circumference of the body, and the outer surface of the bottom of the stopper has the same curvature as the outer circumference of the body, and when the stopper is completely pushed in as described above, the tip surface of each elastic crotch piece is The outer surface of the bottom portion is continuous with the outer circumference of the body portion in the circumferential direction similarly to the outer surface of the intermediate wall 17 of the lateral hole (see FIG. 3). Further, the force that the crotch pieces 22 pinch the optical fiber is slightly reduced by the check claws 23, 23 snapping outwardly, but the force still holds the optical fiber coating portion. In addition, it is preferable that teeth 27 that bite into the coating of the optical fiber are provided on the surfaces of the crotch pieces 22 facing each other in a direction orthogonal to the optical fiber. Also, the elastic piece 25 is also U-shaped, but this does not necessarily have to bite the optical fiber like two crotch pieces.

After the stopper 21 is housed and held in the lateral hole of the body of the main body in this way, the cover cylinder 31 is fitted to the outside of the main body. The cover tube 31 has an inner diameter slightly larger than the outer diameter of the body portion of the main body, and a cylindrical portion 32 that fits on the outer periphery of the body portion, and a front end of the cylindrical portion 32. It consists of a pair of elastic gripping arms 33, 33 located at intervals of 14, 14, the inner circumference of the tip of each gripping arm 33 is thickened to form a jaw 34, and the tip of the inner surface of the jaw 34 is a tapered slope 35. Has become. And the cylindrical portion 32
Holes 36 and 37 for receiving the projection 18 on the body 12 of the main body and the projection 26 on the elastic piece 25 of the stopper 21 are provided on the rear side of the rear side.
Are open to face each other.

The pair of elastic arms 14 projecting from the front end of the body of the main body described above extends straight forward and then bends outward once, and the tip 14 'extends straight forward again. The tip portion 14 'is fan-shaped in cross section and has inclined cam surfaces 19, 19 on both sides.

The elastic arms 14 and 14 are thus bent outward in the middle, and the radius of curvature of the outer circumference of the tip end portion 14 'thereof is larger than that of the outer circumference of the body portion. In order to cover the outer circumference of the body portion 12, both tip portions 14 ', 14' of the elastic arms 14, 14 are pressed inward in the radial direction to be deformed, and in this state, the elastic arms are passed through the cylindrical portion 32 of the cover cylinder. The cylindrical portion 32 is fitted on the outer circumference of the body portion.

Preferably, a jaw 12 'is provided on the outer periphery of the rear end of the body 12, and the rear end of the cylindrical portion 32 is brought into contact with the jaw 12'. Protrusion 1 above
8 and 26 are deformed on the inner periphery of the cylindrical portion 32 while the cylindrical portion 32 is fitted on the outer periphery of the body portion, but when the rear end of the cylindrical portion 32 abuts the jaw 12 '. Since the holes 36 and 37 facing each other are located directly above, the holes 36 and 37 are restored and project into the holes 36 and 37, preventing the cylindrical portion 32 from coming out in the opposite direction. And located at 14 intervals. In this case, the axial lengths of the holes 36, 36 are longer than the projections 18, 26, respectively, and the projection 26 of the elastic piece 25 contacts the rear edge of the hole 36, while the projection 18 has a hole 37.
Contact the leading edge of and keep a gap 1 between it and the trailing edge (see FIG. 2). This interval l is obtained by bending the elastic piece 25 of the stopper 21 and
11 and the stopper 21 held in the lateral hole 16 of the body portion 12 are in a range in which they can be retracted with respect to the cover cylinder 31, and the protrusion 26 of the elastic piece normally locks the rear edge of the hole 36, and the body 11 and the stopper. 21 is elastically pressed forward against the cover cylinder 31.

The insertion port 2 of the connection tube 3 used for the connector of this embodiment has an inner diameter slightly larger than the outer diameter of the tube portion 13 of the main body, and the tube portion 13 of the main body is inserted from each end of the connection tube for connection. A flange 7 is provided on the outer circumference, the front surface of which is gripped by the jaw 34 of the elastic gripping arm 33 of the cover cylinder when each end of the cylinder contacts the front end of the body portion 12 of the main body.

As a result, while inserting the tube portion 13 of the main body into the insertion hole 2 of the connection tube from each end, the connection tube is paired with the elastic arms 14, 14 and the elastic gripping arm 3.
When pushed into the inside surrounded by 3, 33, the elastic gripping arms 33, 33 ride on the flange 7 of the connecting cylinder at the slope 35 of the inner circumference of the tip and bend outward, and when the flange 7 passes the jaw 34, it is elastically restored. The jaw 34 grasps the front surface of the flange 7 and prevents the connecting tube from coming off. At this time, each end of the connecting tube is connected to the body 12 of the main body.
Abut the front end (see FIG. 5).

Therefore, when the connectors are attached to the respective ends of the connecting cylinders as described above, the tips of the core wires 1a protruding from the front ends of the cylinders 13 of the respective connectors are respectively inserted into the insertion holes 2 within the above-mentioned retractable range l.
When it is placed so that it comes out slightly in front of the middle, the tips of the core wires 1a collide with each other in the insertion hole 2 as shown in FIG. 6, and the elastic crotch pieces of the stoppers are respectively bent to retract the main body and the stopper. As a result, the collar 12 'is slightly separated from the rear end of the cylindrical portion 32 of the cover cylinder, and is constantly pushed in the direction of arrow a by the restoring force of the elastic piece 25, and is in proper contact with it. For this reason, if the protruding length of the tip of the core wire from the front end of the tubular portion 13 is set to be a little long, the tip ends of the connected core wires are abutted to each other a little and always come into contact with each other without accurately determining the length. No light transmission loss occurs.

Further, to disconnect the connection, as shown in FIG. 4, the connector 14 is pulled out from the connection tube 3 while pressing the tip portions 14 'of the pair of elastic arms 14 inward in the radial direction as shown by the arrow d. This allows each tip
The inclined cam surfaces 19 and 19 on both sides of 14 'are elastic gripping arms 33 and 33
The elastic gripping arm is deformed outward in the radial direction as shown by the chain line so that each jaw 34 is separated from the flange 7 of the connecting tube. Therefore, the connector is pulled out from the connecting tube 3.

If necessary, a short socket cylinder 38 is provided at the rear end of the body of the main body so as to extend from the through hole 15, and a rubber tube 39 is put over the socket 38 to attach the optical fiber 1 to the rear of the main body. Protect with rubber tube.

Furthermore, in this embodiment, the projection 26 of the elastic piece of the stopper and the projection 18 of the intermediate wall of the body are inserted into the holes 36 and 37 of the cover tube in order to prevent the cover tube from coming out forward. It is not always necessary to plunge in, and the protrusion 18 and the hole 37
May be omitted.

(Effects of the Invention) According to the present invention, it is possible to provide a connector that can be attached to and detached from a connection tube with one touch, and in the state of being attached to the connection tube, the ends of core wires are pressed against each other without causing a loss in the transmitted light.

[Brief description of drawings]

1 is an exploded perspective view of a portion of a connector according to the present invention, FIG. 2 is a sectional view in an assembled state, FIG. 3 is a sectional view taken along line III-III in FIG. 2, and FIG. 4 is a sectional view of FIG. FIG. 5 is a front view, FIG. 5 is a side view showing a state in which the optical fiber is connected to a connecting tube in a 90 ° direction different from that in FIG. 2, which is a sectional view, and FIG. FIG. 7 is a sectional view of a conventional connecting device,
1 is an optical fiber, 1a is its core wire, 2 is an insertion hole, 3 is a connection tube, 11 is a main body, 12 is a body, 14 is an elastic arm, 15 is a through hole, 16
Is a lateral hole, 19 is an inclined cam surface, 21 is a stopper, 22 is an elastic crotch piece, 25 is an elastic piece, 31 is a cover tube, 32 is a cylindrical portion, 33 is an elastic gripping arm, and 34 is a jaw.

Claims (1)

[Claims] 1. A connection tube having a series of insertion holes along the axis for inserting two optical fibers to be connected from each end, and each of the optical fibers is held by penetrating through the connection tube. In a single-core optical fiber connecting device comprising a connector that is connected to the outer circumference of each end and abuts the tips of the cores of the respective optical fibers in the insertion holes of the connecting tube, It has a U-shaped cross-section stopper with two elastic crotch pieces and a through hole for passing an optical fiber along the axis, and the stopper is housed and held in a direction orthogonal to the through hole and orthogonal to the axis. A body having a lateral hole, a body having a pair of elastic arms projecting from the front end of the body in a diametrically opposed manner, and an outer circumference of the body of the body fitted so as to be axially movable and held. And the diametrically opposite A pair of elastic gripping arms projecting in the space between the elastic arms and having a jaw for gripping the outer periphery of the end of the connecting cylinder at the inner circumference of the tip, the cover cylinder having the pair of elastic arms. And the elastic gripping arm is provided with a cam device that opens the elastic gripping arm radially outward when the elastic arm is deformed radially inward, and the stopper is provided with an elastic piece movable in the axial direction of the main body. A connecting device for a single-core optical fiber, characterized in that the elastic piece is locked to a cylindrical portion of a cover cylinder and a stopper and a main body are elastically pressed forward against the cover cylinder.