JPH0383003A - Bayonet lock type optical connector - Google Patents

Abstract

PURPOSE:To prevent the generation of flaws on the surface of an optical fiber by advancing a ferrule to the distance shorter than the distance between the ferrules facing each other even if a knob is rotated by as much as the angle at which the ferrule is fully rotated by a key and the clearance of a key groove at the time of starting the rotation of the knob. CONSTITUTION:The ferrule 7 of an optical plug 3 fixes an optical fiber cord and an optical fiber onto its central axis. A spring 8 is disposed between the flange 7a of the ferrule 7 and the knob 4. The ferrule 7 is pressed in the front end direction thereof by means of a spring 8. The ferrule 7 is connected to the ferrule 10 of the optical plug 2 (of the same shape as the shape of the plug 3) to which this ferrule is opposed when aligned by a sleeve 9 of an optical adapter 1. The distance at which the ferrule advance when the knob is rotated by as much as the max. rotating angle of the ferrule by the key and the clearance of the key groove is made shorter than the distance between the ferrules facing each other at the time of starting the rotation of the knob, by which the rotation of the ferrules after the ferrules are connected to each other is obviated. The effect of suppressing the generation of the flaws on the surface of the optical fiber is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical connector used for optical fiber cable communication, and particularly to an optical connector with a bayonet lock type connection.

[Conventional technology]

Conventionally, with this type of bayonet lock type optical connector, consideration has been given to ensuring that the opposing ferrule end faces meet when the connection is completed, but the positional relationship of the ferrule end faces during the connection process has not been considered. .

[Problem to be solved by the invention]

In the conventional bayonet lock type optical connector described above, the stroker of the ferrule is made long in order to ensure that the opposing ferrule end faces abut against each other. and,
An attempt is made to prevent the ferrule from rotating by providing a key and keyway in the connector, but due to the manufacturing process, there is a clearance between the key and the keyway, so the ferrule rotates as the knob rotates during the connection process. . In particular, optical connectors in which the ferrule end faces are polished into a convex shape as an anti-reflection measure and the opposing optical fibers are brought into contact with each other have the drawback that the aforementioned rotation of the ferrule causes scratches on the optical fiber surfaces.

[Means to solve the problem]

In the bayonet lock type optical connector of the present invention, when an optical connector plug is already attached to one side of the connection adapter and another optical connector plug is connected, the distance between the opposing ferrules when the knob starts rotating is Rather, the distance the ferrule moves forward is shortened even if the knob is rotated by the angle that the ferrule would rotate due to the clearance between the key and the keyway.

In other words, the structure is such that the ferrules have already turned completely by rotating the knob before the ferrules abut each other.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a half-sectional view of an embodiment of the present invention, and FIG. 2 is a zz' cross-sectional view of FIG. The state before being connected to adapter 1 is shown.

A pair of grooves 5 in the shape of a letter 1 are formed from the tip surface of the knob 4 of the optical plug 3, and by hooking the grooves 5 to a pair of locking pins 6 provided on the outer periphery of the tip of the optical adapter 1, the optical plug is removed. 3 is coupled to the optical adapter 1. The ferrule 7 of the optical plug 3 fixes an optical fiber cord and an optical fiber wire on the central axis. A spring 8 is disposed between the flange 7a of the ferrule 7 and the knob 4, and the spring 8 presses the ferrule 7 toward its tip. The ferrule 7 is aligned with the sleeve 9 of the optical adapter 1 and is connected to the ferrule 10 of the opposing optical plug 2 (having the same shape as the plug 1). A key 11 is provided between the ferrule 7 and the knob 4 in parallel to the ferrule 7, and one end of the key is a free end and the other end is fixed to the ferrule 7. The key 11 has a structure that fits into a key groove 12 formed in the optical adapter 1 when the ferrule 7 is inserted into the sleeve 9.

However, as shown in FIG. 2, a clearance inevitably occurs between the key 11 and the keyway 12 due to manufacturing reasons. Now, if the radius of the keyway 12 is A, the width of the key 11 is B, and the length from the center of the optical adapter 1 to the outside of the key 11 is C, then the maximum rotation angle of the ferrule 7 is as shown in FIG. If the distance between the ferrule 7 and the facing ferrule 10 is D when the knob 4 is rotated by aligning the groove 5 formed in the knob 4 of the optical plug 3 with the locking pin 6, then the knob 4 is rotated. If the distance that the ferrule 7 advances when rotated by α is smaller than D, the ferrule 7 will not rotate after being connected to the opposing ferrule 10.

In other words, if the inner radius of knob 4 is E, as shown in the expanded view of the knob in Figure 4, when knob 4 is rotated by α, knob 4 will move by F on the circumference and move forward by G. do. F and G are obtained using equations (2) and (3).

F2a・E・・・・・・(2
)G=F-tanβ・・・・・・(
3) However, β is the angle of the groove 5.

At this time, since the ferrule 7 is being pushed by the spring 8, the ferrule 7 also moves forward by G.

From the above equations (1), (2), and (3), set knob 4 to α
It will only rotate.

That is, the bayonet type optical connector of the present invention The dimensions of each part are set to satisfy the following relationship.

〔Effect of the invention〕

As explained above, when connecting an optical plug to an optical adapter, the present invention allows the knob to be rotated by the maximum rotation angle of the ferrule due to the clearance between the key and the keyway, rather than the distance between the opposing ferrules when the knob starts rotating. By shortening the distance that the ferrules move forward when rotated, the ferrules do not rotate after being connected to each other.

This has the effect of suppressing the occurrence of scratches on the optical fiber surface.

[Brief explanation of drawings]

FIG. 1 is a half-sectional view of an embodiment of the present invention, FIG. 2 is a sectional view taken along the line zz' in FIG. 1, FIG. 3 is a half-sectional view of the process of operation in FIG. 1, and FIG. 2 is an enlarged developed view of the knob 4 in FIG. 1. FIG. l...Optical adapter, 2...Opposing optical plug, 3...Optical plug, 4...Knob, 5...Groove, 6... Locking bottle, 7.
...Ferrule, 8...Spring, 9...
... Sleeve, 10 ... Opposing ferrule, 11 ... Key 12 ... Keyway, A
...Width of key groove 1°2, B...Key 1
1 width, C: Length from the center of key 11 to the outside, D: Distance between ferrule 7 and opposing ferrule 10, E: Inner diameter of knob 4 radius of,
F: Amount of movement on the circumference, G: Amount of forward movement.

Claims (1)

[Claims] First and second optical plugs are connected via an optical adapter in a bayonet locking manner, and a key and a keyway provided on the optical plug and the optical adapter prevent rotation of the ferrule of the optical plug. In the optical connector, the end face of the ferrule of the first optical plug when the locking pin of the optical adapter engages the groove of a knob arranged on the outer periphery of the ferrule of the first optical plug and starts to rotate. Rotate the knob by the maximum angle that the ferrule of the first optical plug can rotate due to the clearance between the key and the keyway, and the distance between the ferrule end faces of the second optical plug facing the first optical plug. A bayonet type optical connector characterized in that the distance that the ferrule of the first optical plug moves forward when the ferrule is moved is short.