US005528712A
`United States Patent 19
`5,528,712
`(11) Patent Number:
`
`[45] Date of Patent: Jun. 18, 1996
`Belenkiyet al.
`
`AAAANETACTN
`
`9/1990 Basista et al.
`4,953,929
`.....sesesesssceeee 350/96.2
`(54] DUPLEX CONNECTOR
`
`
`5,123,071.......cesses 385/536/1992 Mulholland et al.
`
`3/1994. DiMarco... ee eessessssssesssseeseee 385/76
`5,293,581
`
`[76]
`Inventors: Yuriy Belenkiy, 8655 Shermer Rd.,
`6/1994 Rittle et al. sesssseeereeeeeeens 385/76
`5,325,454
`Niles, Dl. 60714; Igor Grois, 4010
`..cecsssecsesensenseeee 385/59
`5,386,487
`1/1995 Briggs et al.
`Greenacre Dr., Northbrook,Ill. 60062;
`Irina Gumin, 9317 Lavergne Ave.,
`Skokie, Il]. 60077; Ilya Makhlin, 492
`S. KiowaTrail, Wheeling, Il]. 60090;
`Mark Margolin, 6611 N. Lawndale,
`Lincolnwood, Il]. 60645; Michael J.
`Pescetto, 5809 Charleston Ct., Hanover
`Park,Ill. 60103
`
`Primary Examiner—John Ngo
`
`[57]
`
`ABSTRACT
`
`[21]
`
`Appl. No.: 383,628
`
`[22]
`
`Filed:
`
`Feb. 6, 1995
`
`[51]
`[52]
`[58]
`
`[56]
`
`Tint, C1.o oocieccecccsessssesssescsssssscesestessesessesecsens G02B 6/36
`US. Cle cesesessesssssssensssssssssssecseescsesneesesseresssasseneesa 385/78
`
`Field of Search ..........c.cccseeens 385/53, 55, 56,
`385/58, 59, 60, 70, 71, 76, 77, 78, 89
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`A duplex connector system is provided for coupling two
`individual simplex fiber optic connectors in a side-by-side
`alignment. Each fiber optic connector includes a housing in
`which an optical fiber cable is terminated through a rear end
`of the housing. First and second strain relief boots are
`respectively interengageable with the housings of the con-
`nectors at the rear ends thereof and encompass the optical
`fiber cables. Resilient portions interconnect the first and
`secondstrain relief boots and are oriented therebetween for
`enabling the boots to hold the connectors in their side-by-
`side alignment while allowing relative motion between the
`connectors during mating and unmating process.
`
`4,687,291
`
`8/1987 Stape et ab. vec cesessssseeseaeees 385/59
`
`10 Claims, 3 Drawing Sheets
`
`Senko EX1024
`PGR2024-00037
`U.S. Patent No. 5,528,712
`
`Senko EX1024
`PGR2024-00037
`U.S. Patent No. 5,528,712
`
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`U.S. Patent
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`5,528,712
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`US. Patent
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`Sheet 2 of 3
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`Jun. 18, 1996
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`5,528,712
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`U.S. Patent
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`5,528,712
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`Jun. 18, 1996
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`Sheet 3 of 3
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`5,528,712
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`1
`DUPLEX CONNECTOR
`
`FIELD OF THE INVENTION
`
`This invention generally relates to the art of fiber optic
`connectors and, particularly, to a duplex connector system
`for coupling two individual simplexfiber optic connectorsin
`a side-by-side alignment.
`BACKGROUND OF THE INVENTION
`
`Fiber optic devicesuse single or multiple strandsoffibers
`each having an inner circular glass core coated with a
`circumferential cladding having a different index of refrac-
`tion. Light is transmitted along the core and totally reflected
`from the interface between the core and cladding. Such
`devices can be used as transmission lines for transmitting
`information bearing light energy. A transmission line can be
`formed from a single fiber or it can include a plurality of
`fibers bundled together. Additionally, several transmission
`lines can be arranged in parallel for the simultaneoustrans-
`mission of information along each of the separate lines.
`Originally, fiber optic systems utilized simplex intercon-
`nection systems with single connector plugs terminating
`single fiber optic cables. In a simplex system, either trans-
`mission or reception of information can take place at one
`time. Consequently, simplex systems are limited in the
`amount of information that they can transmit and receive
`during a given period of time.
`To increase the amount of information that can be com-
`municated over fiber optic systems, multi-channel systems
`were developed. Such multi-channel systems include, for
`example, duplex connector plugs and cables which are
`capable of simultaneous transmission and reception. Thus,
`using a duplex system enables information to be transmitted
`at a much higherrate.
`Despite the advantages, multi-channel fiber optic systems
`are relatively new, and many simplex systems and paris are
`already in use, for example, ST and SC type connectors.
`Consequently, simplex parts are readily available and less
`expensive because there is an existent inventory. Moreover,
`it would be difficult if not cost prohibitive to retrofit existing
`simplex systems with dedicated duplex or other multi-
`channel parts. Consequently, a need exists for an intercon-
`nection system which is compatible with both simplex and
`duplex parts and which permits the interconnection of
`simplex parts in a duplex configuration to provide duplex
`data transmission. Several designs have been proposed to
`address this problem. Typically, they involve an adapter
`structure which clamps on two individual connector hous-
`ingsto hold the two connectorsin a side-by-side relationship
`forming a duplex connector and yet permits relative motion
`between the two individual simplex connectors.
`A problem with the aforesaid adapter structures is that the
`adapters require the provision of an additional structure or
`component of the assembly (i.e. the adapter) beyond the
`ordinary componentsof the fiber optic connectors. One such
`adapter is disclosed in U.S. Pat. No. 4,953,929 to Basista et
`al. which patent is incorporated herein by reference. The
`additional adapter, therefore, adds expense and complexity
`to the duplex assembly. The present
`invention takes a
`completely different approach in making a duplex connector
`assembly from two simplex connectors without the addition
`of extraneous adapterstructures.
`SUMMARY OF THE INVENTION
`
`Anobject, therefore, of the invention is to provide a new
`and improved duplex connector system for coupling two
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`individual simplex fiber optic connectors in a side-by-side
`and parallel alignment.
`Asdisclosed herein, each fiber optic connector includes a
`housing means in which an optical fiber cable is terminated
`through a rear end of the housing means. The invention
`contemplates the provision of first and secondstrain relief
`boots respectively interengageable with the housing means
`of the connectorsat the rear ends thereof and encompassing
`the optical fiber cables. Resilient means interconnectthe first
`and second strain relief boots, with the resilient means
`oriented between the boots for enabling the bootsto hold the
`connectors in a side-by-side alignment.
`In the preferred embodimentof the invention, the strain
`relief boots and the interconnecting resilient means comprise
`an integral structure fabricated of plastic material. The boots
`are generally cylindrical with a conical tail, and the resilient
`means is formed by a pair of integral, spaced-apart thin
`bands extending tangentially between diametrically opposite
`peripheral portions of the boots.
`Other objects, features and advantages of the invention
`will be apparent from the following detailed description
`taken in connection with the accompanying drawings.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`The features of this invention which are believed to be
`novelare set forth with particularity in the appended claims.
`The invention, together with its objects and the advantages
`thereof, may be best understood by referenceto the follow-
`ing description taken in conjunction with the accompanying
`drawings, in which like reference numerals identify like
`elements in the figures and in which:
`FIG. 1 is a perspective view of the duplex connector
`system of the invention coupling two individual simplex
`fiber optic connectors in a side-by-side relationship;
`FIG. 1A is a perspective view of the metal housing insert
`of one of the connectors;
`FIG. 2 is a perspective view, on an enlarged scale, of the
`integral boot structure;
`FIG. 3 is a top plan view of the integral boot structure,
`with one of the boots in section;
`FIG. 4 is a side elevational view of the integral boot
`structure;
`FIG.5 is an end elevational view looking generally in the
`direction of line 5—5 of FIG. 4;
`FIG.6 is a top plan view of the assembly shown in FIG.
`
`1;
`
`FIG.7 is a view similar to that of FIG.6, but with the fiber
`optic connectors rotated 90° from their positions shown in
`FIG.6;
`FIG.8 is an end elevational view looking generally in the
`direction of line 8—8 in FIG. 6; and
`FIG. 9 is an end elevational view looking generally in the
`direction of line 9—9 in FIG.7.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`Referring to the drawings in greater detail, and first to
`FIG, 1, the invention is embodied in a duplex connector
`system, generally designated 10, for coupling two individual
`simplex fiber optic connectors, generally designated 12, ina
`side-by-side alignment, as shown.Eachfiber optic connector
`includes a housing means, generally designated 14, within
`which an optical fiber cable 16 is terminated from a rear end
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`5,528,712
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`18 of the housing. As is knownin the art, each optical fiber
`cable 16 has an outer jacket encompassing a central glass
`fiber 20. The fibers of cables 16 are shown terminated in
`ferrules 22 which project slightly from front ends 24 of
`connector housing means 14. As is known in theart, the
`ferrules may be fabricated of ceramic material.
`Referring to FIG. 1A in conjunction with FIG. 1, each
`housing means 14 of each connector 12 is a two-part housing
`including an inner metal housing insert 14a (FIG. 1A) and
`an outer plastic housing shell 14b (FIG. 1). The optical fiber
`cables 16 are terminated in the ferrules 22 located in the
`metal housing inseris 14a, and the ferrules 22 project
`forwardly from the metal housing inserts.
`The above description of simplex fiber optic connectors
`12 and optical fiber cables 16 is fairly conventional. In
`addition, most fiber optic connectors include strain relief
`boots coupled to the metal connector housing inserts 14a
`and projecting from the rear ends of the outer housing shells
`14b. The strain relief boots encompass the optical fiber
`cables, to provide strain relief for the cables. The present
`invention utilizes these boot structures to provide the duplex
`connector system 10 of the invention.
`More particularly, referring to FIGS. 2-5 in conjunction
`with FIGS. 1 and 1A,the invention contemplates an integral
`boot structure, generally designated 26, which includesfirst
`and secondstrain relief boots 28 encompassing optical fiber
`cables 16. FIG. 3 showsthat each boot28 includesa passage
`30 into which a respective one of the optical fiber cables
`extend. The boots have forward ends 32 whichare insertable
`into outer housing 14b and are mounted on the metal
`housing insert 14a. As illustrated, mounting includes four
`apertures 34 located in each of the forward ends 32 of the
`boots which interengage with corresponding projections 35
`on the outside of the inner housing inserts 14a as seen in
`FIG. 1A. Preferably, integral boot structure 26 is unitarily
`molded of plastic material and, thereby, apertures 34 can
`snappingly interengage with projections 35 on the outside of
`each inner metal housing insert 14a.
`Generally, the invention contemplates the provision of
`resilient means interconnectingfirst and secondstrain relief
`boots 28 and oriented therebetween for enabling the boots to
`hold connectors 12 in a side-by-side alignment as shown in
`FIG.1. In particular, the resilient meansis provided bya pair
`of spaced-apart thin bands 36 which extend between dia-
`metrically opposite peripheral portions of boots 28. In other
`words, the boots are generally cylindrical, and bands 36
`extend generally tangentially between the top and bottom
`peripheral portions of the boots (i.e. on opposite diametric
`sides thereof). The bands and the peripheral portions of the
`boots are provided with serrations or ridges, as at 38, to
`facilitate gripping integral boot structure 26 and assembling
`of the bootstructure to connector housings 14, as well as for
`mating and unmating of the assembled duplex connector 10.
`FIGS. 2 and 5 show how bands 36 are spaced apart by an
`opening 40. Therefore, the thin bands, being fabricated of
`plastic material provide a resilient means between boots 28
`which allows the boots to move in both “X” and “Y”
`directions when subjected to outside forces. Of course, in the
`static condition of integral boot structure 26, simplex fiber
`optic connectors 12 are maintained in the side-by-side
`relationship shownin FIG. 1.
`FIGS. 6-9 show an advantage of the duplex connector
`system of the invention overprior art systems. In particular,
`FIGS. 6 and 8 show simplex fiber optic connectors 12 in
`orientations as depicted in FIG. 1, and coupled to integral
`boot structure 26. On the other hand, FIGS. 7 and 9 show the
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`4
`. connectors rotated 90° relative to their orientations in FIGS.
`6 and8, but with the connectorsstill coupledto integral boot
`structure 26 in their side-by-side alignment. This ability to
`vary the angular orientations of the fiber optic connectors is
`not possible in most systemsof the prior art which include
`separate adapters for clamping onto the exterior of the
`connector housings, because the sides of the outer housing
`shells 14b are different, whereas the coupling means
`between the boots and inner metal housing inserts 14a can
`be omni-directional. The system of the present invention
`takes advantage of this feature while providing a duplex
`system, which cannot be done with the priorart.
`It will be understood that the invention may be embodied
`in other specific forms without departing from the spirit or
`central characteristics thereof. The present examples and
`embodiments, therefore, are to be consideredin all respects
`as illustrative andnotrestrictive, and the invention is not to
`be limited to the details given herein.
`We claim:
`1. A duplex connector system for coupling two individual
`simplex fiber optic connectors in a side-by-side alignment,
`each fiber optic connector including a housing means in
`which an optical fiber cable is terminated through a rear end
`of the housing means, comprising:
`first and second strain relief boots respectively interen-
`gageable with the housing means of the connectors at
`said rear ends thereof and encompassing said optical
`fiber cables; and
`means interconnecting said first and secondstrain relief
`boots and oriented therebetween for enabling the boots
`to hold said connectors in said side-by-side alignment.
`2. The duplex connector system of claim 1 wherein said
`interconnecting means is resilient means allowing relative
`motion between said individual connectors.
`
`3. The duplex connector system of claim 2 wherein said
`strain relief boots and said interconnecting resilient means
`comprise an integral structure.
`4. The duplex connector system of claim 3 wherein said
`integral structure is comprised of plastic material.
`5. The duplex connector system of claim 2 wherein said
`resilient means comprises a band extending between the
`boots.
`
`6. The duplex connector system of claim 2 wherein said
`boots are generally cylindrical, and said resilient means
`comprise a pair of spaced-apart bands extending tangentially
`between diametrically opposite peripheral portions of the
`boots.
`
`7. The duplex connector system of claim 2 wherein said
`housing means of each connector comprises a two-part
`housing including an inner metal housing insert and an outer
`plastic housing shell, and said first and secondstrain relief
`boots are adapted for interengagement with the inner metal
`housing inserts.
`8. In a duplex connector system for coupling two indi-
`vidual simplex fiber optic connectors in a side-by-side
`alignment, with each fiber optic connector including a
`housing means in which an optical fiber cable is terminated
`through a rear end of the housing means,
`wherein the improvement comprises
`an integral boot structure including first and second strain
`relief boot portions respectively interengageable with
`the housing means of the connectors at said rear ends
`thereof and encompassingsaid optical fiber cables, and
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`resilient means integrally interconnecting said first and
`secondstrain relief boots and oriented therebetween for
`enabling the boots to hold said connectors in said
`side-by-side alignment and allow relative motion
`between the two individual connectors.
`9. In a duplex connector system as set forth in claim 8,
`wherein said resilient means comprises a band extending
`between said boot portions.
`
`6
`10. In a duplex connector system as set forth in claim 8
`wherein said boot portions are generally cylindrical, and
`said resilient means comprise a pair of spaced-apart bands
`extending tangentially between diametrically opposite
`peripheral portions of the boot portions.
`
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