JPH0685012B2 - Method of fixing tensile strength fiber to optical connector - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for fixing tensile strength fibers to an optical connector when attaching the optical connector to an end of an optical fiber cord or an optical fiber cable.

(Prior Art) FIG. 2 is a side view showing an upper half cross section of an example of a conventional optical connector. In the drawings, (1) is an optical fiber cord or optical fiber cable, (2) is an optical fiber core wire constituting the above cord or cable, (3) is an end portion of the optical fiber core wire (2) and an optical fiber positioning fixing The optical connector ferrule (4) integrally formed with these is a tensile strength fiber incorporated in the optical fiber cord or the optical fiber cable (1).

Then, the tensile strength fiber (4) is taken out from the cut end of the outer coating of the optical fiber cord or the cable (1), and the end portion of the optical connector ferrule (3) is axially moved through the pressing spring (22). Extend along the taper of the rear end of the pushing wheel (23) that is being pressed, insert the tensile strength fiber retainer (24) on it, and caulk it to fix the tensile strength fiber (4) or use an adhesive. It is designed to be fixed to the push ring (23) together with the tensile strength fiber retainer (24) by using.

In the drawings, (18) is an adapter housing, (19)
Is a split sleeve for connection for positioning and coupling the optical connector ferrules (3) located in the adapter housing (18) inserted from both sides, (21) is an insertion guide for coupling with the adapter housing (18), (25 ) Is a tensile fiber presser
A rubber boot that encloses (24) and is inserted on the outer coating of the optical fiber cord or cable (1) to protect these end portions.

(Problems to be Solved) What is important in fixing the tensile strength fiber as described above is to fix the tensile strength fiber without causing slack. This is because it is easy to imagine when tension is applied to the optical fiber cord or cable, but if the tensile strength fiber sags, the tension when pulling the optical fiber cord or cable will be higher than that of the tensile strength fiber. It becomes impossible to load the wire and bear the tension with the tensile strength fiber. Therefore, to repeat again, two important points in fixing the tensile strength fiber are to firmly fix the tensile strength fiber and to prevent the tensile strength fiber from sagging at the time of fixing. In particular, when optical contact is made to the glass part of the optical connector ferrule to reduce coupling loss and reflection, this tendency becomes more remarkable, and it is possible to remove the slack of the tensile strength fiber and fix it with a slight tension applied. It will be extremely important.

However, in the above-mentioned conventional fixing structure, although the tensile strength fibers are sufficiently fixed by the push ring and the tensile strength fiber retainer, the slack of the tensile strength fibers is removed, and the fixing in a state in which a slight tension is applied is easy. The reality is that it is not in a state and working method that can be done. By the way, a sample of n = 10 was manufactured by caulking tensile strength fiber, and the coupling loss was continuously measured while applying a tension of 10 kg, but up to 6 out of 10 optical connector ferrules before loading 10 kg. The tension was transmitted to the joint and the coupling loss increased.

(Means for Solving Problems) The present invention provides a method for fixing a tensile strength fiber to an optical connector which solves the above problems, and is characterized by a tensile strength fiber incorporated in an optical fiber cord or an optical fiber cable. After temporarily fixing the end part of the above with a temporary fixing ring which is elastically deformed in the radial direction in advance on a push ring having a taper formed at the end, a tensile strength fiber retainer whose inner surface is tapered,
Using a tensile strength fiber tightening nut that has a collect chuck whose rear part is larger than the outer diameter of the optical fiber cord or optical fiber cable, clamps and fixes the tensile strength fiber between the outside of the tensile strength fiber and the push ring. In addition, the code or the cable is also fixed by the collect chuck.

(Embodiment) FIG. 1 shows a longitudinal sectional view of an embodiment of an optical connector assembled by using the tensile strength fiber fixing method of the present invention, and the same symbols as those in FIG. 2 represent the same portions.

In this embodiment, the tensile strength fiber (4) contained in the optical fiber cord (1) is taken out from the cut end of the outer coating of the optical fiber cord (1) and presses the optical connector ferrule (3) with the spring (12). ) Is extended in the axial direction via a taper part having a taper of about 15 degrees provided at the rear part of the push wheel (13), and on the push wheel (13) at the back of the push wheel (13). It is fixed by a temporary fixing ring (14) that elastically deforms in the radial direction,
Behind this temporary fixing ring (14) is a tensile strength fiber retainer (1) having a taper inner surface that engages with the above-mentioned tapered portion of the push ring (13).
5) is located, and the tensile strength fiber retainer (15) is fixed by the tensile strength fiber tightening nut (16) screw-connected to this.
(4) is clamped and fixed so that it is sandwiched between the push ring (13).

A collet chuck larger than the outer diameter of the optical fiber cord (1) is formed on the rear part (16a) of the tensile strength fiber tightening nut (16), and the optical fiber cord is tightened after fixing the tensile strength fiber (4). The optical fiber cord (1) is fixed by connecting the nut (17).

Next, a method of fixing the tensile strength fiber to the optical connector will be described. The optical fiber cord (1) has an outer diameter of about 3 mmφ,
A tensile strength fiber (4) is built inside, and an optical connector ferrule (3) is attached to the tip. The optical connector ferrule (3) is pressed and fixed by the pressing spring (12) using the insertion guide (11) and the push ring (13). After that, the tensile strength fiber (4) taken out from the cut end of the outer coating of the optical fiber cord (1) is placed along the outside of the rear tapered portion of the push ring (13),
Tighten with the temporary stop ring (14), then the temporary stop ring (14)
Using the tensile strength fiber retainer (15) that has a taper at its tip that engages the tapered portion of the push ring (13) on the inner surface, use the tensile strength fiber retainer (15) that has a taper at its tip Push in. At this time, the temporary fixing ring (14) is elastically deformed in the radial direction and pushed inward as the taper portion rides up.
Pull (4) forward. This is one of the points of the present invention, whereby the slack of the tensile strength fiber (4) is removed, and the temporary fastening ring (1
It is temporarily fixed on the push wheel (13) by 4). Since the tensile strength fiber (4) is thus temporarily fixed, the tensile strength fiber does not sag at this stage even if the hand is removed from the optical connector, and the next work can be easily performed.

In this state, insert the tensile strength fiber tightening nut (16) into the push ring (13) so that the tensile strength fiber retainer (15) previously inserted through the optical fiber cord (1) is pressed. The tensile strength fiber (4) is screwed to the outer peripheral portion, and is clamped and fixed by sandwiching the tensile strength fiber (4) between the pressing ring (13) and the tensile strength fiber retainer (15).

Further, a collet chuck type claw is provided on the rear portion (16a) of the tensile strength fiber tightening nut (16), and after fastening and fixing the tensile strength fiber (4), the optical fiber cord tightening nut (17) is joined. This tightens the outer coating layer of the optical fiber cord (1) to fix the optical fiber cord (1).

Although the optical fiber cord has been described above, it goes without saying that the optical fiber cord can be applied to an optical fiber cable having a tensile strength fiber and having a plurality of cores. Further, FIG. 1 shows a push-on type optical connector in which the claw of the adapter housing and the groove of the plug part are fitted and the outside is fixed by the ejector guide. Of course, this connection structure is not the only option, and screw connection, bayonet It is widely applicable.

(Experimental example) The results of measuring the coupling loss and the variation of the coupling loss of the optical connector assembled by the above-mentioned method for fixing the tensile strength fiber of the present invention are as follows.

That is, the coupling loss is 0.13 dB on average and 0.23 dB at maximum in the sample of n = 20 by making the optical contact.
The minimum was 0.08 dB, and the coupling loss was continuously monitored with respect to tensile strength, but the variation of the coupling loss was ± 0.02 dB or less at all loads of 10 kg or less for n = 20. ± 5m
Even in the vibration test of m, 10HZ to 50HZ and 5 hours in 2 directions, the coupling loss variation is ± 0.02dB or less, and in each case, the reliability is sufficient.

(Effects of the Invention) According to the tensile strength fiber fixing method of the present invention, the following effects are exhibited.

By temporarily fixing the tensile strength fiber to the taper part at the rear of the push ring by using the temporary tensile strength fiber ring, it is possible to easily remove the slack of the tensile strength fiber inside the optical connector. Can keep the coupling loss constant.

The device for pushing the tensile strength fiber temporary fixing ring into the back can be easily realized by using the tensile strength fiber retainer and does not require any special tool.

By forming a collet chuck for fixing the jacket of the optical fiber cord on the rear part of the tightening nut for fixing the tensile strength fiber presser, the cord tightening nut is tightened, and the optical fiber cord is used without using an adhesive or the like. The outer cover of can be fixed.

By fixing the outer cover of the optical fiber cord with a collet chuck type, the cord can be fixed without twisting.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of an embodiment of an optical connector assembled by using the method of fixing a tensile strength fiber of the present invention, and FIG. 2 is a longitudinal sectional view of an example of a conventional optical connector. 1 ... Optical fiber cord, 2 ... Optical fiber core wire, 3 ...
… Optical connector ferrule, 4… Tensile fiber, 13… Push ring, 14… Tensile fiber temporary fixing ring, 15… Tensile fiber retainer, 16… Tensile fiber tightening nut, 17… Optical fiber cord tightening nut.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Yasuo Asano 1 Taya-cho, Totsuka-ku, Yokohama-shi, Kanagawa Sumitomo Electric Industries, Ltd. Yokohama Works (72) Inventor Shuzo Suzuki, 1 Taya-cho, Totsuka-ku, Yokohama-shi, Kanagawa Sumitomo Denki Kogyo Co., Ltd.Yokohama Works (72) Inventor Shinji Nagasawa 162 Shirahane, Shikata, Tokai-mura, Naka-gun, Ibaraki Prefecture Nippon Telegraph and Telephone Corporation, Ibaraki Telecommunications Research Institute (72) Izumi Mikawa, Naka Ibaraki Prefecture 162, Shirahone, Shirokata, Tokai-mura, Gunma, Japan, Telegraph and Telephone Research Institute, Nippon Telegraph and Telephone Corporation (56) References JP-A-58-211725 (JP, A) JP-A-59-9614 (JP, A) Actual Open 60-8907 (JP, U) Actual open 58-109710 (JP, U) Actual open 58-180516 (JP, U)

Claims (2)

[Claims] 1. A terminal portion of a tensile strength fiber incorporated in an optical fiber cord or an optical fiber cable is temporarily fixed on a push ring having a taper end by a temporary fixing ring which is elastically deformed in the radial direction in advance. Using a tensile strength fiber tightening nut that has a collect chuck whose rear portion is larger than the outer diameter of the optical fiber cord or optical fiber cable, presses the tensile strength fiber retainer whose inner surface is tapered from the outside of the tensile strength fiber with the pressing ring. A method for fixing a tensile strength fiber to an optical connector, characterized in that the tensile strength fiber is clamped and fixed between them, and the cord or cable is also fixed together by the collect chuck. 2. The method for fixing tensile strength fibers to an optical connector according to claim 1, wherein the temporary fixing ring is mounted on the push ring by pushing in with the tip of the tensile strength fiber retainer.