JPS62215210A - Optical connector - Google Patents

Abstract

PURPOSE:To obtain an optical connector which is reduced in diameter and length by forming an optical connector ferrule cylindrically and using a split sleeve where the holding force of the optical connector of a sleeve in an adapter is specified. CONSTITUTION:The split sleeve 1 has an internal diameter smaller than the external diameter of the optical connector ferrule 8 inserted into the sleeve as well as a conventional split sleeve, but the ratio is small and the holding force to the optical connector ferrule 8 is <=400g, thereby preventing an optical fiber core 6 from being broken owing to repetitive attachment and detachment. Further, the optical connector ferrule 8 is formed in the shape of a uniform- diameter cylinder by having no collar part, the external diameter of the optical connector is reduced correspondingly, and a pressure spring 4 is positioned on the end part of the optical fiber core 6, thereby pressing the rear surface of the optical connector ferrule 8. Consequently, the optical connector ferrule 8 is shortened by at least the length of the collar part.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an optical connector that attaches an optical connector ferrule to the end of a coated optical fiber and realizes mutual coupling of the coated optical fibers via an adapter.

(Prior Art and Problems to Be Solved) FIG. 2 shows an external side view of an optical connector ferrule used in a conventional optical connector. The optical connector ferrule 0D is formed by a sleeve insertion part GZ at the front, a collar part 02 at the middle, and a rear part 041. In the drawings, reference numeral 09 indicates an optical fiber core wire positioned and fixed by the optical connector ferrule OD. Therefore, in connection, the sleeve insertion part Ob at the front of the ferrule is inserted into the sleeve provided in the adapter, and axial pressure is applied to fix it in the sleeve of the adapter, thereby realizing the connection. At this time, the front surface (13a) of the ferrule collar o3 positions the optical connector ferrule in the sleeve in the axial direction. Note that such an optical connector ferrule is provided with a housing on its outer periphery, and its outer diameter reaches 9.8 mmφ.

However, it is difficult to install an optical connector equipped with the above-mentioned optical connector ferrule OD at the end of each optical fiber of an optical fiber cable having a large number of optical fibers. This is not possible as a practical matter due to the large outer diameter, and it has become essential to reduce the diameter of optical connectors, and at the same time, it is also required to reduce the length of optical connectors.

The above-mentioned reduction in diameter involves attaching a small-diameter optical connector directly to the optical fiber/core wire, so compression and tension are applied during connection, but by removing the coating of the optical fiber core wire, the tensile strength can be reduced to an average of 700 g to 1 kg, and some sandals weigh around 500 g. On the other hand, the optical connector ferrule holding force of the split sleeve in the conventional adapter is 500g~
Since the weight is 800g, wire breakage occurs when the ferrule is attached or detached. If a disconnection occurs, the optical connector ferrule must be reattached to the optical fiber core. However, reinstallation requires time-consuming work such as gluing the optical connector ferrule and the optical fiber, and polishing the end face of the optical connector ferrule.Moreover, since it is installed directly to the optical fiber core wire that has been made into a cable, the remaining work is extremely limited. This is an important problem that must be solved, as it must be installed within the length range, and there is a possibility that the cable will become unusable due to missing length as a result of reinstallation.

Furthermore, as optical connectors used for permanent connections between optical cables become shorter, the screw length of the press ring that presses and fixes the optical connector ferrule in the axial direction must be shortened, which prevents the screw from loosening. There is also the problem that it can come off.

(Means for Solving the Problems) The present invention solves the above-mentioned problems and provides an optical connector that has a smaller diameter and shorter length. The reason is that the retaining force of the optical connector ferrule of the sleeve inside the adapter is achieved by using a split sleeve of 4009 or less.

(Embodiment) FIG. 1 shows a longitudinal sectional view of an embodiment of the optical connector of the present invention in a coupled state. In the drawing, (1) is a split sleeve attached to the inner periphery of the sleeve-shaped adapter, and (3) is an inserter that is attached to the rear outer periphery of the optical connector ferrule (8) and includes a pressure spring (4). The insertion guide (■) is equipped with a threaded part (9) that engages with the threaded part on the inner circumferential surface of the rear part of the insertion guide, and presses the pressure spring (4) against the rear surface of the optical connector ferrule (■) to insert the optical connector ferrule (8). ■ is the optical fiber core whose end is positioned and fixed in the optical connector ferrule (8)'; ■ is the push ring that positions and fixes the end of the optical fiber core inside the optical connector ferrule (8); Reinforced pipes such as nylon pipes that provide mechanical protection and reinforcement.

Therefore, the above-mentioned split sleeve (1) is similar to the conventional split sleeve, and the optical connector ferrule (8) is inserted into it.
) has an inner diameter smaller than the outer diameter of the optical connector ferrule. Optical fiber core (6)
Prevent wire breakage.

The spectroscopic connector has a cylindrical shape with a uniform diameter and has a small outer diameter. Along with this, the pressure spring (4) is attached to the rear QΦ of the optical connector ferrule as in the conventional case.
Rather than being located above and pressing the rear surface of the collar (+3b),
It is located on the end of the optical fiber core 0 and presses against the rear surface of the optical connector ferrule B).

With such a configuration, the optical connector ferrule (2) can be shortened by at least the length of the flange, making it possible to shorten the length.

1 Furthermore, a fixing agent is applied to the rear inner circumferential surface of the insurge gin guide (3) and the threaded portion (2) of the push ring (2), so that the two are fixed to the extent that they can be detached from each other. This adhesive can be provided by, for example, coating the outer periphery of the threaded portion of the press ring (1) with a highly reactive adhesive in microcapsules in advance. In this way, by fixing the threaded part of the insertion guide ■ and the push ring ■ with an adhesive, the connection between the two becomes strong, making it possible to shorten the threaded part and making the optical connector shorter. Helpful.

(Experiment example) Holding force for optical connector ferrule (8) is 400g
Using the adapter ■ equipped with the split sleeve (1) below,
An optical connector as shown in Fig. 1 was fabricated and evaluated using a push ring whose threaded portion was pre-coated with a micro-encapsulated acrylic type highly reactive adhesive.

As shown in Fig. 1, insert the optical connector ferrule e from both ends of the adapter (2), press it with the spring (4) and butt it together, and position it with the split sleeve (1). 7 I did. The dimensions of the optical connector ferrule (8) at this time are an outer diameter of 2.499maφ and a length of 10m11. The dimensions of the optical connector were an outer diameter of 3.5 mmφ and a length of 40 W.

It was below dB. Also, 50H2±15mml0 hours, 2
As a result of the vibration test for the direction, the loss fluctuation range was 0.
．． There is no loosening of the screw part below 05dB, -30℃~+
As a result of a heat cycle test at 70°C for 100 hours, the loss fluctuation range was 0.2 dB or less, and as a result of an impact drop test in which the joint was naturally dropped from 1 m to the floor, the loss fluctuation range was 0.2 dB.
As a result of a thermal test of dB or less, 80℃, 95%, 100 hours, the loss fluctuation range was 0.2 dB or less, which was good, and there was no disconnection at all even after 1000 connections and disconnections, so there was no problem in practical use. was confirmed.

(Effect of the invention) According to the double optical connector of the present invention, the holding force is 40
By using a split sleeve of 0 g or less, there is no disconnection even when the optical fiber core wire with the optical connector ferrule is repeatedly attached to and detached from the adapter, and the reliability of the optical connector is significantly improved.

By using a cylindrical body with a large diameter, it became possible to reduce the outer diameter of the optical connector, making it practical for multi-core optical fiber cables.

Furthermore, by providing a bonding agent in the threaded part of the push ring and insertion guide, the connection between the two becomes strong.
The length of the screw part can be shortened, making it possible to shorten the length of the optical connector, and eliminating the need for troublesome on-site work to prevent screws from loosening.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of the optical connector of the present invention in a coupled state, and FIG. 2 is an external side view of an example of a conventional optical connector ferrule. ■... Split sleeve, 2... Adapter, 3... Insertion guide, 4... Pressure spring, 5... Push ring, 6... Optical fiber core, 8... Light connector ferrule.

Claims (2)

[Claims] (1) In an optical connector that attaches an optical connector ferrule to the end of an optical fiber core and achieves coupling via an adapter, the optical connector ferrule is cylindrical, and the holding force of the optical connector ferrule of the sleeve inside the adapter is 400 g.
An optical connector that is realized by the split sleeve shown below. (2) The push ring that presses the optical connector ferrule in the axial direction via the pressure spring and the threaded portion of the inner periphery of the insertion guide are fixed with a bonding agent. optical connector.