JPS59198411A - Centering method and device of ferrule for optical connector - Google Patents

Abstract

PURPOSE:To attain the best centering action and to avoid the connection loss due to variance by inserting and fixing a centering prism, which is formed into a regular polygonal prism having arcuate recessed parts, to a core holding part. CONSTITUTION:A ferrule 1 is constituted with a core holding part 2 of bundled fibers and a sheath holding part 4 which has spring receiving jaws 3 on the outside circumference. A V-shaped guide groove 5 is provided on the outside circumference of the holding part 2. A rib 8 for the groove 5 is provided in an inside hole 7 of a sleeve 6. A positioning tap 9 is constituted with a centering prism 10, a substrate 11, bending arms 12, etc. The centering prism 10 has recessed grooves 14 on the outside circumference, and cores are engaged with these grooves. A projecting part 13 for the groove 5 is provided on one arm 12. Consequently, when the centering prism is inserted into the core holding part 2 to engage the projecting part 13 with the groove 5, the holding part 2 and the tap 9 are positioned, and cores P are supported in recessed parts 14 of the prism 10 and are always held in certain positions. After an adhesive is hardened, the end part of the tap 9 is cut along a line B.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical fiber connector in which the axes of the core wires are aligned to minimize connection loss in a bundle fiber with a small number of core wires.

In a conventional optical fiber connector (hereinafter simply referred to as an optical connector), a single fiber core IJit b is attached to a cylindrical ferrule a as shown in FIG.

It has been proposed that six core wires S, b, ... are packed in the closest density around the center to eliminate axis misalignment between the core wires. However, this is because the core wires b+, b2, etc. are not positioned relative to the ferrule a, which tends to cause axis misalignment as a whole as shown by the two-dot chain line, and it is still necessary to reduce the connection loss in relation to the other ferrule. It was difficult. As a method to solve this problem, it has been proposed to form the ferrule a' as a regular hexagonal cylinder as shown in FIG. 2, and to make the inner hole of the corresponding sleeve C also hexagonal. In this case, the core wires S, b2, etc. are positioned at the corner of the inner hole of the ferrule a' as shown in Fig. 3, and the ferrule a' is further aligned with the sleeve C, so that the axis of the mating ferrule is The deviation can be reduced.

Ferrule a', sleeve C, etc. can be easily manufactured by plastic molding, but considering their accuracy and usage environment, brass is difficult to rust and has good machinability (in addition, dimensional deviations are small during long storage and actual use). It is best to use metal materials such as.

However, in the case of metal materials, it is very difficult and time consuming to form the hexagonal inner holes of the ferrule a' and the sleeve C with high precision. Therefore, there are problems in that mass production is not possible and costs are high, and since a certain level of precision cannot be ensured, connection loss due to axis misalignment still increases, and variations in the fiber core diameter cannot be absorbed.

This invention was made to solve the above problem.In an optical connector that connects bundled fibers with a small number of core wires, by inserting a positioning plug into the core wire holding part of the ferrule, it is possible to prevent the core wire from being misaligned. It is an object of the present invention to provide an alignment method and device for an optical connector that absorbs variations in core wire diameter and reduces connection loss.

The present invention will be explained below with reference to the drawings. In Fig. 4, reference numeral 1 denotes a ferrule made of synthetic resin or a metal material such as brass, with a handle fiber core holding part 2 in the front half and an outer periphery in the rear half. A jacket holding part 4 having a spring receiving collar 3 is formed, and a V-shaped guide groove 5 is provided in the outer periphery of the core wire holding part 2 in the axial direction. Reference numeral 6 denotes a sleeve for inserting and holding a pair of opposing ferrules 1 from both sides, and a rib 8 facing the inner hole 7 and corresponding to the guide groove 5 is provided.
is installed protrudingly.

Reference numeral 9 denotes a positioning plug, and a pair of curved arms 12 extending toward the alignment column 1o are provided at both ends of a base plate 11 that supports the base end of the alignment column 1o, and one arm 12 has the guide groove. A protrusion 13 is provided protruding from the protrusion 5.

This alignment column 10 is formed into a regular hexagonal column shape with arcuate recesses 14 on each side, and a taper 15 is provided at the tip.

The arcuate shape R of the arcuate recess 14 is as shown in FIG.
The virtual circle S formed between the ferrule core wire holder 2 and the fiber core wire p is designed to have the same diameter or a slightly larger diameter than the fiber core wire p.

Next, the assembly of the optical connector will be explained.

First, as shown in FIG. 6, a handle fiber p whose tip has been peeled off to expose the core wire p is inserted from the side of the sheath holding portion 4 of the ferrule 1, and is made to protrude from the tip of the core wire holding portion 2.
At this time, an adhesive A such as a two-component epoxy resin is applied in advance to the exposed core wires P so that the adhesive is sufficiently applied between the core wires 9 and between the core wire holding parts. Next, the positioning stopper 9 is inserted from the core wire holding part 2 side. At this time, one arm 1
By aligning the protrusions 13 of 2 with the guide grooves 5 of the core wire holder 2 and inserting the alignment post 10, the core wire holder 2 and the positioning stopper 9 are positioned, and the fiber cores p are aligned with the alignment post 10. Since each core wire p is held by the ten arcuate recesses 14 and the inner wall of the core wire holder 2, each core wire p is always held at a constant position in relation to the core wire holder 2.

Next, after the adhesive has hardened, the positioning stopper 9 is attached using the Kento process.
When the alignment column 10 and arm 12 are ground to the dotted line B in FIG. As a result, the fiber core wire p is always fixed at a fixed position with respect to the ferrule 1 via the alignment column 1o.

Next, the sleeve 6 is inserted into the optical connector main body (not shown), and the ferrule 1, which has received and fixed the optical fiber p as described above, is inserted into its guide groove 5 from both sides of the sleeve 60.
By inserting the bundle fibers so that the fibers and the ribs 8 are aligned with each other, it is possible to obtain an optical connector with extremely low connection loss and no axis misalignment between the fiber bundles. It should be noted that the left and right ferrules 1 are configured such that springs (not shown) wound around the jacket holding part 4 are pressed forward by a spring receiver 3, so that the end surfaces of the core wires p are brought into close contact with each other.

Figures 8 (a) to (c) show modified shapes of the alignment column 10 in the positioning plug 9, (a) is for 5 cores, (b)
(C) is for 7 cores, and (C) is for 10 cores. In this way, the shape of the alignment column 10 can be formed into a desired regular polygonal column shape depending on the number of core wires constituting the bundle fiber. Furthermore, by making the alignment column 10 and the arm 12 unrotatable and allowing them to be engaged and separated, the arm 12 can be removed during the grinding process.
It is also possible to remove the core wire p and polish the core wire p efficiently.

As explained above, this invention has the following advantages because a regular polygonal column-shaped alignment column with arc-shaped recesses on each side is inserted and fixed into the core wire holding portion of the ferrule.

■) By selecting a positioning stopper with an appropriate centering column according to the number of cores of the handle fiber, the best centering action can always be achieved.

2) Since variations in the fiber core wire are individually absorbed by the arc-shaped recesses of the alignment column, the splice loss is not affected by the difference in the variation in the core wire diameter and is stable.

3) Since the positioning stopper can be separated by polishing, only the shape of the alignment column needs to be changed in response to changes in the number of core wires.

4) Since the component shape is simple, it is easy to manufacture, and since high precision is not required, it can be manufactured at low cost, and the assembly work of the optical connector is also simple.

[Brief explanation of the drawing]

1 to 3 are explanatory diagrams of a conventional optical connector, FIG. 4 is a perspective view of an embodiment of this invention in a separated state, FIG. 5 is a perspective view of a positioning plug, and FIG. An explanatory diagram showing the mutual relationship between the ferrule core wire holder and the alignment column as above, FIG. 7 is an explanatory diagram of the assembled state of the optical connector as above, and FIG. 8 shows another embodiment of the alignment column as above. FIG. DESCRIPTION OF SYMBOLS 1... Ferrule, 2... Core wire holding part, 4... Outer covering holding part, 5... Guide groove, 6... Sleeve, 8...
... Rib, 9 ... Positioning stopper, 10 ... Alignment column, 1
2...Arm. 7th @ R (A) (Tl)
(c) Procedural amendment (voluntary) October 21, 1980 Patent Office Commissioner Kazuo Sugi 1, Indication of case 1981 Patent No. 72226
No. 2, Title of the invention: Method and device for aligning 7 errules for Hikashi optical connectors 3, Relationship with the case of the person making the amendment Special r: Applicant Address: 1-4-28 Mita, Minato-ku, Tokyo Name: Valve ÷ (689) ) Yazaki Sogyo Co., Ltd. 4, Agent 5, Amendment Order B (”l Showa year
Date 8, Contents of the amendment As shown in the attached document, Contents of the amendment (@Gan Sho 58-72226) 1, Page 5 of the specification cylinder, lines 5-6, ``Between the ferrule core wire holding part 2 and...
" is replaced with "Between the ferrule core wire holding part 2"
and correct it. 2. On page 5, line 9 of the same cylinder, replace “Fig. 6” with “Fig. 7”.
Correct it to "Fig." 3. On page 6, line 5 of the same page, the text ``Figure 1 Figure 6'' is amended to read ``Figure 7''. Patent applicant Yazaki Sogyo Co., Ltd.

Claims (2)

[Claims] (1) Consisting of a ferrule that accommodates an optical fiber and has a core wire holding portion in the front half, and a positioning stopper that has a polygonal alignment column with an arcuate recess on each surface, the alignment column is connected to the core wire holding portion. After inserting the positioning stopper into the core wire holder and positioning and fixing the core wire of the optical fiber between the arcuate recess and the inner wall of the core wire holder, A method for aligning a ferrule for an optical connector, characterized by separating a positioning plug while leaving a core pillar. (2) A ferrule that accommodates an optical fiber and has a core wire holding part in the front half, and a polygonal column-shaped alignment column with arc-shaped recesses on each surface in the center, and the outer periphery of the core wire holding part with substrates on both sides. A ferrule for an optical connector, comprising a positioning stopper provided with an arm that engages in a predetermined position, and in which only an alignment column portion of the positioning stopper is located within the core wire holding part when the positioning stopper is connected to the ferrule. Alignment device.