JPS6095413A - Optical connector - Google Patents

Abstract

PURPOSE:To reduce the number of parts and to improve the performance of an optical connector at low cost by providing a plug shaft, a lock screw which is fitted rotatably in the circumferential direction and movably in the axial direction, and a means which prevents the lock screw from falling in the loosening direction. CONSTITUTION:The projection 18 of the lock screw 15 is freely movable between a lock screw presser 14 and a spring 16 unless it is connected to an adapter. When projection is closer to the lock screw presser 14, a key pin 22 for the positioning during coupling with the adapter is seen and the connector is inserted into the adapter smoothly. When the lock screw 15 is clamped, the projection 18 contacts the spring 16 to apply the force which pressing out the step 19 of the plug shaft 17, and the step 20 of the lock screw 15 abuts on the adapter to fix the lock screw 15. In this state, the surface 21 of the plug shaft 17 is pressed against the adapter by the spring 16 with constant force and an end surface 23 is coupled with the adapter side stably. Thus, the performance is improved with a small number of parts.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical connector having a simple structure and a small number of parts.

[Technical background and problems of the invention]

Conventionally, the widely popular FA (Field Aaa
The emblem) type optical connector is constructed as shown in Fig. 1, and is firmly fixed to one end of an optical fiber cord J, which is made by sequentially covering an optical fiber 7 with a jacket 12, a Kepra 1, and an outer sheath 1. It is.

To assemble such an optical connector, pass the rubber cord 2, cap 3, Kevlar stopper 4, bushing 5, and spring 6 through the optical fiber cord LJ, and process the optical fiber 1 to ensure precise dimensional accuracy. Pass it through the hole in the center of the ferrule 8 where it is exposed and fix it with adhesive. After the adhesive hardens, 7
Machining rule 8 Polish the end faces and attach spring 6 and bushing 5.
Pull back and insert the plug frame 10 through the lock screw 9.
and fix it with bushing 5. Thereafter, the Keppler 11 exposed from the outer sheath 1 of the optical fiber cord 13 is passed between the bushing 5 and the Keppler stopper 4, and after being fixed with the cap 3, the rubber hood 2 is attached.

However, as mentioned above, the FA type optical connector has many parts, eight in this example.

Also, assembly is complicated, especially for Kevlar processing (Kevlar must be fixed in a fixed position under tension).
, Attach the plug frame (it is necessary to fix the ferrule 8 so that it fits into the stopper of the bushing 5 so that the ferrule 8 does not rotate, and so that the spring 6 can move freely)
This is difficult, and the work must be carried out with the optical fiber jacket 12 exposed throughout, so care must be taken.

OBJECTS OF THE INVENTION It is an object of the present invention to provide an optical connector that has a significantly reduced number of parts, is easy to assemble, and can be manufactured at a low price, although its performance is almost the same as that of the conventional connector.

[Summary of the invention]

This invention provides an optical fiber cord in which an optical fiber is coated with a jacket, a jacket, and an outer sheath, and the optical fiber, the jacket, and the jacket are exposed at one end for a predetermined length, and the exposed light A plug shaft that covers the fiber, jacket and Keppra and is fixed to the optical fiber cord and has a keybin; a rubber hood that covers the outer jacket and a part of the plug shaft; This optical connector is provided with a step, and includes a lock screw fitted to the outer periphery of the plug shaft so as to be rotatable and movable in the axial direction, and a means for preventing the lock screw from coming off in the loosening direction.

[Embodiments of the invention]

The optical connector of the present invention is constructed as shown in FIG.
A plug is attached to one end of the optical fiber cord 24.

That is, the optical fiber cordom 4 is formed by sequentially covering an optical fiber 26 with a jacket 27, a Kevlar 28, and a jacket 29, and a predetermined length of each of the optical fiber 26, the jacket 27, and the Kevlar 28 is exposed at one end. are doing. The plug shaft 11 is fixed to cover the exposed optical fiber 26, jacket 27, and Kevlar 28. The plug shaft 17 has a cylindrical shape and supports an optical fiber 26 at its tip and a jacket 29 at its rear end, and has a key pin 22 at a position near the tip.
are provided integrally, and a step 19 is formed on the outer periphery in the middle. Further, an annular recess is provided on the outer periphery of the rear end of the plug shaft 17, and a means for preventing a lock screw (described later) from coming off in the loosening direction, such as a lock screw retainer 14, is provided in this recess. This lock screw holder 14, the rear end of the plug shaft 17, and the outer sheath 29 of the optical fiber cord U
A rubber hood 13 is attached to cover it. Furthermore,
A lock screw 15 is fitted to cover a portion of the rubber hood 13 and most of the plug shaft 17 so as to be rotatable and movable in the axial direction. A threaded portion 32 is formed on the inner periphery of the P-thread screw 15 near the light leakage area, and a step 2° and a protrusion 18 are provided at the rear of the threaded portion 32.

One surface of this protrusion 18 can come into contact with the layered surface of the μ-tuck screw retainer 14 and the rubber pad 13', and the other surface can come into contact with the helical spring 16 disposed between the lock screw 15 and the plug shaft 17. It is possible.

For assembled VC, the outer sheath 29 of the optical fiber cord 24
Rubber hood 13, P screw holder 14, lock screw 1
5. Pass the spring 16 through, and after processing the optical fiber 26, adhesively fix it to the plug shaft 17. After that, the end face of the plug shaft 11 is polished, and the spring 16 and the P screw 15 are polished.
, the lock screw 15 is rotatably locked with the P-took screw holder 14, and the rubber 7-cord 13 is attached for reinforcement to complete the process.

In use, when the optical connector is not connected to an adapter (not shown), the protrusion 18 of the P screw 15 is inserted between the lock screw retainer 14 and the spring 160 (spring 16
If there is no plug, it can move freely between the steps 19 of the plug shaft 17). When it is closer to the lock screw presser 14 side, the keybin 22 necessary for positioning when coupling with the adapter becomes visible, allowing smooth insertion into the adapter. Thereafter, when the lock screw 15 is brought close to the spring iegt1j, the screw of the adapter and the threaded portion 32 of the lock screw 15 can be connected without receiving the repulsive force of the spring. When the lock screw 15 is subsequently tightened, the protrusion 18 is transmitted to the spring 16, and a force is applied to push out the plug shaft 170 step 19 (when the spring 16 is not present, the protrusion 18
directly pushes out the step 19).

When the P screw 15 is subsequently tightened, the lock screw 150 and the step 20 collide with the adapter, and the P screw 15 is fixed. In this state, the plug shaft 170 surface 21 is always pressed against the adapter with a constant force by the repulsive force of the spring 16, and the end surface 23 is stably connected to the adapter side.

〔Effect of the invention〕

According to this invention, since the number of parts is small and assembly is easy, it is possible to reduce the price without degrading the performance of the conventional device.

[Modified example of the invention]

3 and 4 show a modification of this invention,
The same effects as in the above embodiment can be obtained.

That is, in the above embodiment, the lock screw retainer 14 was fitted with a C-shaped ring, but as shown in FIG. It is also possible to fix the rubber 7-cord 13 reliably, thereby creating a structure in which the rubber 7-cord 13 is difficult to come off.

In addition, FIG. 4 shows that the lock screw holder is fixed to the plug shaft 17, and instead of that, the protrusion of the lock screw 15 is fixed to the C-shaped ring Stt.
This is an example in which exactly the same effect as the above embodiment can be obtained by configuring the following.

The outer diameter of the part of the plug shaft 17 that fits with the adapter is 1 μm.
Because extremely high precision tolerances are required, the plug shaft 11 is manufactured by dividing it into two parts, the 7 errule 3θ and the plug shaft body 31, as shown in Fig. 4.Then, they are bonded, press-fitted, shrink-fitted, screwed, It is preferable to integrate them by welding or other methods. As a result, the following effects are added.

(2) By forming the ferrule 30 into a cylinder or stepped cylinder with a shape such that the diameter of the adapter fitting portion is the maximum, the outer diameter can be manufactured by wrapping with high accuracy and high productivity.

■For the 7-erule 30, which requires wear resistance, use, for example, hardened stainless steel 440C or double-walled steel, and for the plug shaft body 31, which does not require much precision or wear resistance, use, for example, stainless steel 303 or brass casting, which has good workability. By using φ, an inexpensive and high-performance plug shaft 17 can be obtained.

In addition, in FIGS. 2 and 3, the keybin 22 that prevents the rotation of the optical connector is integrally machined with the plug shaft 17, but as in the modification shown in FIG. It goes without saying that the effects of the present invention can be obtained even if the plug is fixed to the plug shaft 17 by some means or even if there is no keybin.

[Brief explanation of drawings]

@Figure 1 is a cross-sectional view showing a conventional FA type optical connector, wJz
The figure is a sectional view showing an FA type optical connector according to an embodiment of the present invention, and FIGS. 3 and 4 are sectional views showing modified examples of the invention. 13...Rubber hood, 14...Lock screw press, J
5...Lock screw, 16...Spring, 17...Plug shaft, 18...Protrusion, 19...Step, 20...
Step, 22...Key vinyl/, 24...Optical fiber cord, 25...Plug, 26...Optical fiber, 21
... Jacket, JIB ... Kepra, 29 ... Outer cover, 30 ... 7 errule, 81 ... Plug shaft body,
32...screw part.

Claims (3)

[Claims] (1) A plug shaft, a lock screw having a threaded portion near the tip of the inner circumference, a step provided at the rear of the threaded portion, and fitted to the outer circumference of the plug shaft so as to be rotatable and movable in the axial direction; An optical connector characterized by comprising means for preventing a lock screw from coming out in the loosening direction. (2) The optical connector according to claim 1, wherein a spring is disposed between the plug shaft and the lock screw. (3) The optical connector according to claims 1 and 2, wherein the plug shaft is formed by integrating a cylindrical ferrule that holds the optical fiber and the jacket, and a plug shaft body that holds the means. .