CA1113760A - Magnetic connector for optical cables - Google Patents
Magnetic connector for optical cablesInfo
- Publication number
- CA1113760A CA1113760A CA326,030A CA326030A CA1113760A CA 1113760 A CA1113760 A CA 1113760A CA 326030 A CA326030 A CA 326030A CA 1113760 A CA1113760 A CA 1113760A
- Authority
- CA
- Canada
- Prior art keywords
- connector
- housings
- face
- end faces
- cable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
- G02B6/24—Coupling light guides
- G02B6/36—Mechanical coupling means
- G02B6/38—Mechanical coupling means having fibre to fibre mating means
- G02B6/3807—Dismountable connectors, i.e. comprising plugs
- G02B6/3873—Connectors using guide surfaces for aligning ferrule ends, e.g. tubes, sleeves, V-grooves, rods, pins, balls
- G02B6/3886—Magnetic means to align ferrule ends
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Mechanical Coupling Of Light Guides (AREA)
Abstract
Abstract:
A magnetic connector for optical cables comprises a pair of identical connector members of non-ferromagnetic material fitted to the respective cable ends and adapted to be brought together to align the ends of the fibres of the respective cables.
Toroidal magnets mounted on the connector member produce mutually assisting magnetic fields parallel to the alignment of the fibre ends, which are covered by ferromagnetic material and so are held firmly together by the fields. A liquid of suitable refractive index may be interposed between the fibre ends to avoid optical discontinuities.
A magnetic connector for optical cables comprises a pair of identical connector members of non-ferromagnetic material fitted to the respective cable ends and adapted to be brought together to align the ends of the fibres of the respective cables.
Toroidal magnets mounted on the connector member produce mutually assisting magnetic fields parallel to the alignment of the fibre ends, which are covered by ferromagnetic material and so are held firmly together by the fields. A liquid of suitable refractive index may be interposed between the fibre ends to avoid optical discontinuities.
Description
1~1371~
The present invention relates to optical fibres and is particularly concerned with a magnetic connector for optical cables, i.e. light conducting cables, comprising one or more optical fibres.
A very important practical problem, which arises when optical fibres are used in transmission systems, is to make good connections between fibre trunks in order to minimize coupling losses.
These losses are caused both by imperfect alignment of the fibre ends to be connected, i.e. by lack of parallelism and by lateral misalignment of the fibre axes, and also by the dis-continuity in refractive index near the junction point.
In order to align the fibre ends, devices having sleeve guides or V-groove guides, in which the fibres are held in the correct position by adhesives or resilient means, are generally used, and matching of the refractive index is effected by suit-able liquid substances interposed between the fibre ends.
These devices, while satisfactory for permanent splices, present a number of problems when used in connectors, since the delicacy of their structure does not permit the frequent joining and separating operations typically required with connectors.
These problems are mitigated by the present invention of a magnetic connector for optical cables, whose main feature is its easy placement at the cable ends, allowing connection to be made without difficulty and with good alignment between the single optical fibres. Another feature of the connector is that it does not require mechanical parts having exacting requirements of accuracy or calibration but may be carried out by means of two identical parts, thereby reducing the production costs to a minimum.
According to the present invention a connector for coupling together a pair of light-conducting cables each comprising a plurality of optical fibres to be joined to , corresponding fibres of the other cable, comprises: a pair of housings of nonmagnetic material having closely juxtaposable confronting end faces, each of said housings further having an entrance port remote from the end face thereof and a plurality of channels extending from said channels toward said end face, said channels terminating in wider recesses opening onto said end faces; retaining means securing an optical cable to the entrance port of each of said housings with each fibre of each cable guidedly traversing one of said channels and terminating at said end face of the respective housing in an extremity laterally movable in the corresponding recess, said extremity being peripherally coated with a tubular ferromagnetic layer;
locating means for relatively orienting said end faces to bring corresponding fibre extremities of said cables within their respective recesses into substantial alignment with each other upon juxtaposition of said housings; and active magnetic means for inducing in the interior of the juxtaposed housing a magnetic field substantially perpendicular to said end faces generating in said ferromagnetic layers a flux for precisely aligning said corresponding fibre extremities with each other.
One embodiment of the present invention will now be described by way of example with reference to the accompanying drawing, which is a central longitudinal sectional view of a magnetic connector in accordance with the invention.
In the drawing, CO and CO indicate the optical ends of a cable to be connected. Each end comprises, for example, three optical fibres indicated respectively by Fl, F2, F3 and Fl , F2 , F3 .
ReferencesC and C denote two housings made of non-ferromagnetic materials, in which the optical fibres of the cable are located. These housings are provided with means S and S for locking the optical cable, stuffing boxes for example, and with resiliently fitting means G, G , for f~ ~ 2 -~1376~) :
preventing the establishment of concentrated mechanical stresses on the cable near the connector.
Reference L and L denote two pins or projections which key into complementary cavities N and N thereby to allow ~'''''''" ' , .:
..
' '; ' ' .. .
.
. .
~ 2a ~
1~13~
alignment of the connector parts while preventing at the same time any relative rotation between them.
References M and M' denote two permanent magnets of toroidal shape. The magnetic fields inside the materials present flux lines parallel to the rotational axis of the magnets such that, when the two connector parts are placed face to face in the con-nected position shown, the fields are in the same sense.
Lastly, Rl, R3, R3, and Rl', R2', R3' denote cylindrical coverings of ferromagnetic material, placed on the single fibre ends; their function will be explained during the description of the connector operation.
The application of these coverings may be effected by means of simple mechanical processes or by utilizing well-known methods of chemical or electrochemical deposition.
The assembling of each connector part at the respective end -~ of the optical cable does not present particular difficulties, since it consists simply in inserting the single fibres, already bared of the protective coating and covered at the ends with the cylindrical coverings of ferromagnetic material, in the guides provided in the housings C, C' and in locking the optical cable by the stuffing boxes S and S'.
At this point, the connector parts may be brought together so as to align the protrusions L and L' with the cavities N and N'. The magnets M and M' since they produce parallel and con-cordant magnetic fields, effect a mutual attraction and therefore the two connector parts keep firmly together.
If the magnetic attraction is insufficient> the two con-nector parts may be kept in position by means of a bayonet joint, a threaded locking ring or any other well-known device.
7~
The ends of fibres Fl, F2 and F3, already roughly pre-aligned by the cylindrical guides located in the housings C and C', are facing the corresponding ends of fibres Fl', F2' and F3' and are separated from the latter by a thin gap. Their accurate alignment is achieved by the magnetic field, lying parallel to the axes of the fibres and produced by permanent magnets M and M'. In fact, in consequence of the induced magnetization in the ferromagnetic coverings placed on the fibre ends, a mutual attraction between the facing fibres and alignment of the respective ends along the flux lines of the magnetic field are obtained.
Through a suitable choice of the ratio of the magnet length to its diameter, an essentially constant field parallel to the ro-tational axis of the magnets can be obtained. Therefore the fibre alignment can reach a mechanical accuracy otherwise not obtainable except by means of complicated laboratory apparatus.
In order to a~oid any discontinuity in the refractive index, a fluid of suitable refractive index is interposed between the - fibre ends. It may be dripped inside the connector through an opening provided in the housing C or C' for the purpose.
The above description has been given by way of example and not in a limiting sense. Variations and modifications may be made without departing from the scope of the invention. More particularly, the connector may present not only axial symmetry with radially arranged fibres, but also any prismatic shape with the fibres arranged on superimposed planes.
Moreover, the magnetic field may be produced both by per-menent magnets and by an electromagnet or solenoid having any shape, provided that the flux lines are parallel to the single optical fibre ends.
.
The present invention relates to optical fibres and is particularly concerned with a magnetic connector for optical cables, i.e. light conducting cables, comprising one or more optical fibres.
A very important practical problem, which arises when optical fibres are used in transmission systems, is to make good connections between fibre trunks in order to minimize coupling losses.
These losses are caused both by imperfect alignment of the fibre ends to be connected, i.e. by lack of parallelism and by lateral misalignment of the fibre axes, and also by the dis-continuity in refractive index near the junction point.
In order to align the fibre ends, devices having sleeve guides or V-groove guides, in which the fibres are held in the correct position by adhesives or resilient means, are generally used, and matching of the refractive index is effected by suit-able liquid substances interposed between the fibre ends.
These devices, while satisfactory for permanent splices, present a number of problems when used in connectors, since the delicacy of their structure does not permit the frequent joining and separating operations typically required with connectors.
These problems are mitigated by the present invention of a magnetic connector for optical cables, whose main feature is its easy placement at the cable ends, allowing connection to be made without difficulty and with good alignment between the single optical fibres. Another feature of the connector is that it does not require mechanical parts having exacting requirements of accuracy or calibration but may be carried out by means of two identical parts, thereby reducing the production costs to a minimum.
According to the present invention a connector for coupling together a pair of light-conducting cables each comprising a plurality of optical fibres to be joined to , corresponding fibres of the other cable, comprises: a pair of housings of nonmagnetic material having closely juxtaposable confronting end faces, each of said housings further having an entrance port remote from the end face thereof and a plurality of channels extending from said channels toward said end face, said channels terminating in wider recesses opening onto said end faces; retaining means securing an optical cable to the entrance port of each of said housings with each fibre of each cable guidedly traversing one of said channels and terminating at said end face of the respective housing in an extremity laterally movable in the corresponding recess, said extremity being peripherally coated with a tubular ferromagnetic layer;
locating means for relatively orienting said end faces to bring corresponding fibre extremities of said cables within their respective recesses into substantial alignment with each other upon juxtaposition of said housings; and active magnetic means for inducing in the interior of the juxtaposed housing a magnetic field substantially perpendicular to said end faces generating in said ferromagnetic layers a flux for precisely aligning said corresponding fibre extremities with each other.
One embodiment of the present invention will now be described by way of example with reference to the accompanying drawing, which is a central longitudinal sectional view of a magnetic connector in accordance with the invention.
In the drawing, CO and CO indicate the optical ends of a cable to be connected. Each end comprises, for example, three optical fibres indicated respectively by Fl, F2, F3 and Fl , F2 , F3 .
ReferencesC and C denote two housings made of non-ferromagnetic materials, in which the optical fibres of the cable are located. These housings are provided with means S and S for locking the optical cable, stuffing boxes for example, and with resiliently fitting means G, G , for f~ ~ 2 -~1376~) :
preventing the establishment of concentrated mechanical stresses on the cable near the connector.
Reference L and L denote two pins or projections which key into complementary cavities N and N thereby to allow ~'''''''" ' , .:
..
' '; ' ' .. .
.
. .
~ 2a ~
1~13~
alignment of the connector parts while preventing at the same time any relative rotation between them.
References M and M' denote two permanent magnets of toroidal shape. The magnetic fields inside the materials present flux lines parallel to the rotational axis of the magnets such that, when the two connector parts are placed face to face in the con-nected position shown, the fields are in the same sense.
Lastly, Rl, R3, R3, and Rl', R2', R3' denote cylindrical coverings of ferromagnetic material, placed on the single fibre ends; their function will be explained during the description of the connector operation.
The application of these coverings may be effected by means of simple mechanical processes or by utilizing well-known methods of chemical or electrochemical deposition.
The assembling of each connector part at the respective end -~ of the optical cable does not present particular difficulties, since it consists simply in inserting the single fibres, already bared of the protective coating and covered at the ends with the cylindrical coverings of ferromagnetic material, in the guides provided in the housings C, C' and in locking the optical cable by the stuffing boxes S and S'.
At this point, the connector parts may be brought together so as to align the protrusions L and L' with the cavities N and N'. The magnets M and M' since they produce parallel and con-cordant magnetic fields, effect a mutual attraction and therefore the two connector parts keep firmly together.
If the magnetic attraction is insufficient> the two con-nector parts may be kept in position by means of a bayonet joint, a threaded locking ring or any other well-known device.
7~
The ends of fibres Fl, F2 and F3, already roughly pre-aligned by the cylindrical guides located in the housings C and C', are facing the corresponding ends of fibres Fl', F2' and F3' and are separated from the latter by a thin gap. Their accurate alignment is achieved by the magnetic field, lying parallel to the axes of the fibres and produced by permanent magnets M and M'. In fact, in consequence of the induced magnetization in the ferromagnetic coverings placed on the fibre ends, a mutual attraction between the facing fibres and alignment of the respective ends along the flux lines of the magnetic field are obtained.
Through a suitable choice of the ratio of the magnet length to its diameter, an essentially constant field parallel to the ro-tational axis of the magnets can be obtained. Therefore the fibre alignment can reach a mechanical accuracy otherwise not obtainable except by means of complicated laboratory apparatus.
In order to a~oid any discontinuity in the refractive index, a fluid of suitable refractive index is interposed between the - fibre ends. It may be dripped inside the connector through an opening provided in the housing C or C' for the purpose.
The above description has been given by way of example and not in a limiting sense. Variations and modifications may be made without departing from the scope of the invention. More particularly, the connector may present not only axial symmetry with radially arranged fibres, but also any prismatic shape with the fibres arranged on superimposed planes.
Moreover, the magnetic field may be produced both by per-menent magnets and by an electromagnet or solenoid having any shape, provided that the flux lines are parallel to the single optical fibre ends.
.
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A connector for coupling together a pair of light-conducting cables each comprising a plurality of optical fibres to be joined to corresponding fibres of the other cable, comprising:
a pair of housings of nonmagnetic material having closely juxtaposable confronting end faces, each of said housings further having an entrance port remote from the end face thereof and a plurality of channels extending from said entrance port toward said end face, said channels terminating in wider recesses opening onto said end faces;
retaining means securing an optical cable to the entrance port of each of said housings with each fibre of each cable guidedly traversing one of said channels and terminating at said end face of the respective housing in an extremity laterally movable in the corresponding recess, said extremity being peripherally coated with a tubular ferromagnetic layer;
locating means for relatively orienting said end faces to bring corresponding fibre extremities of said cables within their respective recesses into substantial alignment with each other upon juxtaposition of said housings; and active magnetic means for inducing in the interior of the juxtaposed housing a magnetic field substantially perpend-icular to said end faces generating in said ferromagnetic layers a flux for precisely aligning said corresponding fibre extremities with each other.
a pair of housings of nonmagnetic material having closely juxtaposable confronting end faces, each of said housings further having an entrance port remote from the end face thereof and a plurality of channels extending from said entrance port toward said end face, said channels terminating in wider recesses opening onto said end faces;
retaining means securing an optical cable to the entrance port of each of said housings with each fibre of each cable guidedly traversing one of said channels and terminating at said end face of the respective housing in an extremity laterally movable in the corresponding recess, said extremity being peripherally coated with a tubular ferromagnetic layer;
locating means for relatively orienting said end faces to bring corresponding fibre extremities of said cables within their respective recesses into substantial alignment with each other upon juxtaposition of said housings; and active magnetic means for inducing in the interior of the juxtaposed housing a magnetic field substantially perpend-icular to said end faces generating in said ferromagnetic layers a flux for precisely aligning said corresponding fibre extremities with each other.
2. A connector as defined in claim 1 wherein said active magnetic means comprises a pair of annular magnets respectively surrounding said housings with aiding polarities.
3. A connector as defined in claim 2 wherein said annular magnets are flush with said end faces for coming into mutual contact upon juxtaposition of said housings.
4. A connector as defined in claim 1, 2 or 3 wherein said locator means comprises a projection on each end face and a complementary depression on the respective other end face.
5. A connector as defined in claim 1, wherein said retaining means comprises a clamping nut engaging the entrance port of each housing.
6. A connector as defined in claim 5 wherein said retaining means further comprises an elastic sleeve surrounding said clamping nut and bearing upon an unclamped portion of the respective cable.
7. A connector as defined in claim 1, 2 or 3 wherein said housings are mutually identical.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT67933-A/78 | 1978-04-26 | ||
| IT67933/78A IT1107327B (en) | 1978-04-26 | 1978-04-26 | MAGNETIC ONLECTOR FOR OPTICAL CABLES |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1113760A true CA1113760A (en) | 1981-12-08 |
Family
ID=11306466
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA326,030A Expired CA1113760A (en) | 1978-04-26 | 1979-04-20 | Magnetic connector for optical cables |
Country Status (7)
| Country | Link |
|---|---|
| JP (1) | JPS59803B2 (en) |
| CA (1) | CA1113760A (en) |
| DE (1) | DE2916763C2 (en) |
| FR (1) | FR2424554B1 (en) |
| GB (1) | GB2020055B (en) |
| IT (1) | IT1107327B (en) |
| NL (1) | NL174498C (en) |
Families Citing this family (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2496281A1 (en) * | 1980-12-16 | 1982-06-18 | Kokusai Denshin Denwa Co Ltd | ROTARY JOINT FOR OPTICAL FIBERS |
| US4449210A (en) * | 1981-12-21 | 1984-05-15 | Hughes Aircraft Company | Fiber optic hydrophone transducers |
| IT1205397B (en) * | 1983-11-10 | 1989-03-15 | Cselt Centro Studi Lab Telecom | CONNECTOR FOR OPTICAL FIBERS |
| US4690495A (en) * | 1984-11-14 | 1987-09-01 | Giannini Gabriel M | Optical fiber magnetic connector |
| AT383898B (en) * | 1985-07-05 | 1987-09-10 | Gebauer & Griller | DEVICE FOR DETACHABLE COUPLING OF TWO LIGHT GUIDES |
| US5369627A (en) * | 1987-07-21 | 1994-11-29 | Seiko Epson Corporation | Improvements in bearing and frame structure of a timepiece |
| JPH0157706U (en) * | 1987-10-06 | 1989-04-11 | ||
| DE3921344A1 (en) * | 1989-06-29 | 1991-01-10 | Hengstler Gmbh | External data programming unit - has magnetically latched cable coupling providing communication with programmable controller |
| US5295212A (en) * | 1992-10-29 | 1994-03-15 | Eldec Corporation | System for transmitting signals between optical transceivers |
| JPH09258072A (en) * | 1996-01-19 | 1997-10-03 | Sony Corp | Optical data transmission connector |
| DE19802173B4 (en) * | 1998-01-19 | 2004-06-17 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Arrangement for the fine adjustment of an optical fiber-chip coupling |
| DE10248969B4 (en) * | 2002-10-17 | 2005-12-29 | Infineon Technologies Ag | Method for producing an optical arrangement |
| DE102006053775A1 (en) * | 2006-11-15 | 2008-05-21 | Mtu Aero Engines Gmbh | Optical fiber coupling |
| DE202011003983U1 (en) | 2011-03-15 | 2011-05-12 | Bürkert Werke GmbH | Optical fiber coupling |
| US8734024B2 (en) * | 2011-11-28 | 2014-05-27 | Corning Cable Systems Llc | Optical couplings having a coded magnetic array, and connector assemblies and electronic devices having the same |
| DE102012212254B3 (en) * | 2012-07-12 | 2014-01-09 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Connector for cable-free signal transmission |
| JP6441016B2 (en) * | 2014-10-07 | 2018-12-19 | 三菱鉛筆株式会社 | Optical coupling member, optical connector and electrical connector |
| EP3206064A4 (en) | 2014-10-07 | 2018-06-27 | Mitsubishi Pencil Co., Ltd. | Optical coupling member, optical connector and electric connector |
| WO2021111589A1 (en) * | 2019-12-05 | 2021-06-10 | 日本電信電話株式会社 | Optical connector and optical connection structure |
| US11287579B2 (en) | 2020-04-06 | 2022-03-29 | Lockheed Martin Corporation | Non-rigid blind mate connector system |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3790791A (en) * | 1972-07-20 | 1974-02-05 | Bunker Ramo | Optoelectronic cable assembly |
| US3963323A (en) * | 1974-12-23 | 1976-06-15 | International Telephone And Telegraph Corporation | Fiber optic connector with protective cable sleeves |
| FR2305746A1 (en) * | 1975-03-25 | 1976-10-22 | Trt Telecom Radio Electr | CONNECTOR FOR OPTICAL FIBERS |
| JPS5237443A (en) * | 1975-09-20 | 1977-03-23 | Showa Electric Wire & Cable Co Ltd | Junction part of optical fiber cables and process for connection there of |
| DE2646010C3 (en) * | 1976-10-12 | 1979-05-17 | Siemens Ag, 1000 Berlin Und 8000 Muenchen | Magnetic coupling device for connector plugs |
| DE2645991A1 (en) * | 1976-10-12 | 1978-04-13 | Siemens Ag | Photoconductor cable connection with magnetic coupling - has alignment and centering of individual strands performed by guide grooves |
-
1978
- 1978-04-26 IT IT67933/78A patent/IT1107327B/en active
-
1979
- 1979-04-18 GB GB7913525A patent/GB2020055B/en not_active Expired
- 1979-04-18 FR FR7909716A patent/FR2424554B1/en not_active Expired
- 1979-04-20 CA CA326,030A patent/CA1113760A/en not_active Expired
- 1979-04-24 JP JP54049855A patent/JPS59803B2/en not_active Expired
- 1979-04-25 DE DE2916763A patent/DE2916763C2/en not_active Expired
- 1979-04-25 NL NLAANVRAGE7903252,A patent/NL174498C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| GB2020055A (en) | 1979-11-07 |
| JPS59803B2 (en) | 1984-01-09 |
| NL174498B (en) | 1984-01-16 |
| IT1107327B (en) | 1985-11-25 |
| IT7867933A0 (en) | 1978-04-26 |
| GB2020055B (en) | 1982-06-30 |
| DE2916763C2 (en) | 1983-08-25 |
| FR2424554B1 (en) | 1986-03-28 |
| JPS54158243A (en) | 1979-12-13 |
| DE2916763A1 (en) | 1979-10-31 |
| FR2424554A1 (en) | 1979-11-23 |
| NL7903252A (en) | 1979-10-30 |
| NL174498C (en) | 1984-06-18 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |