DE2916763A1 - CONNECTOR FOR OPTICAL CABLES - Google Patents

Description

Optical cable connector

The invention relates to a connector for optical cables, which may comprise one or more optical fibers, and makes use of magnetic forces.

A very significant practical problem in using optical Fibers in transmission systems consists in making good connections between the fiber pieces in order to reduce coupling losses to keep it to a minimum. These losses are caused by imperfect alignment of the fiber ends to be connected, thus due to a lack of parallelism and lateral misalignment of the fiber axes, as well as due to the discontinuity caused by the refractive index at the junction.

In an effort to align the fiber ends exactly with one another, are generally sleeve-shaped or V-groove shaped devices Uses guides in which the fibers are held in the correct position by adhesive or spring means, and the adjustment of the refractive index is made possible by suitable liquid substances that are introduced between the fiber ends, causes. While such devices give satisfactory permanent splices, they are problematic when used in detachable connectors because the sensitivity of their construction is not typical of such connectors frequent connection and disconnection operations allowed. These disadvantages are caused by the invention characterized in claim 1 overcome, whereby the main property of the magnetic connection

908844/0988

Another thing for the optical cable is that it is easily attached to the Cable ends can be attached and connected without difficulty and good alignment between each optical Fibers allowed. There are other properties of the connector in that it does not need any mechanical parts with special requirements in terms of accuracy or calibration, and in addition can be made of two identical parts, so that the production costs can be kept low .

Further details, advantages and developments of the invention emerge from the subclaims and from the following description of a preferred embodiment with reference to the drawing, the only figure of which is a medial Represents a longitudinal section through a connector according to the invention.

In the exemplary embodiment shown, two ends of optical cables CO and CO 'are to be connected to one another, each of which comprises, for example, three optical fibers F1, F2, F3 or F1', F2 'and F3'. The ends of the optical fibers belonging to the cables are arranged in two housings C and C made of non-magnetic material, which are provided with cable ^{locking devices S and S 1} , for example glands, for locking the optical cables and with resilient fastening pieces G and G ' in order to avoid the occurrence of concentrated mechanical loads in the cable close to the connector.

Two projections L and L 'can be inserted into corresponding recesses N and N ^1, respectively. They represent two locking points, which enable the mutual alignment of the connector parts and at the same time prevent their mutual rotation.

The connector comprises two ring-shaped permanent magnets M and M ¹ with magnetic fields whose lines of flux within the materials run parallel to the axes of rotation of the magnets, namely,

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when the two connector parts are arranged face to face in the connecting position, with the same direction " Permanent magnets can also have a toroidal shape. Furthermore, the connector comprises cylindrical ones arranged around the individual fiber ends Coverings R1, R2, R3 and RV, R2 ', R3' made of ferromagnetic Material. Their function will be explained later in the description of how the connector works. These Casings can be made using simple mechanical processes or by using known chemical or chemical techniques electrochemical deposition can be produced.

The assembly of each of the connector parts on one of the ends of the optical cables is not difficult, since it simply consists in the individual fibers, after they have already been stripped of any protective coating and covered at the ends with the cylindrical sheaths made of the ferromagnetic material, in to introduce the guides provided for this purpose in the housings C and C and to fix ^{the optical cables by means of the cable locking devices S and S 1, respectively.}

The connector parts on both sides can then be brought closer to one another in such a way that the projections L and L- 'coincide with the recesses N and N. ¹ , respectively. Since the magnets M and M ¹ generate parallel magnetic fields in the same direction, they cause mutual attraction so that the two connector parts hold together firmly. If the magnetic attraction is insufficient, the two connector parts can also or still be held in the closed position with the aid of bayonet locks, screwed locking rings or other aids known per se.

The ends of the fibers F1, F2 and F3 already roughly pre-aligned by the cylindrical guides in the housings C and C ^{are opposite the corresponding ends of the fibers FV, F2 1} and F3 'and are only separated from them by a narrow gap. Their exact alignment is determined by the magnetic field

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is enough, which is generated by the permanent magnets M and M ¹ parallel to the fiber axes. In fact, as a result of the induced magnetization of the ferromagnetic sheaths R1, R2 and R3 or RV, R2 'and R3' sitting on the fiber ends, there is a mutual attraction between the opposing fibers and an alignment of related ends along the lines of flux of the Magnetic field.

By a suitable choice of the ratio of the length to the diameter of the magnets, a field which is essentially constant and parallel to the axes of rotation of the magnets can be obtained. The fiber alignment thus achieves an accuracy that is mechanical could only be achieved with the help of complicated laboratory equipment.

In order to avoid any discontinuity in the index of refraction, a fluid of suitable index of refraction is placed between the fiber ends brought in. It can be dripped into the interior of the connector through an opening made for this purpose in housing C or C is present.

The embodiment described can be modified in various ways v / earth. For example, the connector can not only be axially symmetrical with radially distributed fibers, but can also be of prismatic shape with fibers arranged in superimposed planes. The magnetic field can also be from both Permanent magnets as well as with the help of an electromagnet or solenoid of any shape under the condition that the lines of flux run parallel to the individual optical fiber ends are generated.

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Claims (5)

Claims 1. Connector for optical cables with one or more optical fibers, characterized in that it consists of two identical parts, each of which is arranged at one end of the cable and comprises the following parts: - a device (M, M ')> inserted in the body of the connector
A magnetic field is generated with lines of flux parallel to the axes of the ends of the optical fibers (F1, F2, F3; Ft ¹ , F2 ', F3') belonging to the optical cables (CO, CO ^{1) to be connected to one another;} - Non-magnetic housings (C, C) for the cable ends, with internal ones cylindrical guides for receiving and pre-aligning the ends of the optical fibers; - ferromagnetic devices (R1, R2, R3; R1 ·, R2 ' _s R3 ^! ) which are attached to the ends of the optical fibers and, as a result of the induced magnetization, an attraction and precise alignment of the opposite ends of the optical fibers along the lines of flux of the magnetic field. 2. Connector according to claim 1, characterized in that the device (M, M ¹ ) generating the magnetic field is partially integral 909844/0988 with one and partially integral with the other connector part and a parallel and co-directional magnetization to achieve mutual attraction of the two connector parts and brings about their cohesion. 3. Connector according to claim 1 or 2, characterized in that the optical cables (CO, CO · ¹ ) are lockable with the corresponding connector parts (by S, S '). 4. Connector according to one of claims 1 to 3, characterized in that the cables are fastened ^{to the connector by resilient means (G, G 1) preventing the occurrence of mechanical concentrated stresses in the cables close to the connector.} 5. Connector according to one of claims 1 to 4, characterized in that that aids the index adjustment of the opposing Cause ends of the optical fibers. 903844/0988 / 3