MXPA97010473A - Fiber optic connector for optical fibers with separate extremes and bezel - Google Patents

Abstract

The present invention relates to a device for interconnecting two naked optical fibers, characterized in that it comprises: a receptacle having a clamping element that can be moved between the open and closed states, the clamping element is adapted to fix the bare ends of the fibers in optical connection in the closed state, a first plug or plug assembly having a first fiber optic thereon, a terminal end face of the first fiber optic bevelled, the first plug assembly includes: a first plug socket which it has first and second ends, a first sleeve means for fixing a portion of the first fiber inside the male plug housing and for positioning the first fiber close to the first end of the first male plug housing, and a first means for biasing the first sleeve means towards the first end of the first male plug housing for placing a preloaded condition on the first fiber when the first male plug housing is inserted into the receptacle, and a second male plug assembly having a second optical fiber thereon, a terminal end face of the second fiber is also bevelled, the second male plug assembly includes a second male plug housing having a first and second ends, a second sleeve means for fixing a portion of the second fiber within the second male plug housing and for positioning the second fiber near the first end of the second male plug housing so that the terminal end faces of the first and second fibers are held in compressed engagement.

Description

OPTICAL FIBER OPTIC DK CONNECTOR FOR OPTICAL FIBERS WITH SEPARATE AND BEZELED EXTREMES BACKGROUND OF THE INVENTION 1___ Cf »" p9 f the Invention The present invention relates generally to connectors, and more particularly to connectors that can be coupled for optical waveguides such as fibers used in telecommunications.

-A Description of the prior art Many single-mode discrete fiber optic connector or plug designs currently in use contain precision cylindrical ceramic ferrules or ferrules that are mounted on the connector plugs. The bare glass optical fibers are joined in the close-fitting axial perforations in these ferrules, and the tips of the fiber and the ferrule are polished to provide low insertion loss and retroreflection connections. The connector housings used in these ferrule connector plugs may contain dividing ceramic sleeves which center and REF: 26479 align the ferrules when the connector plugs are inserted at opposite ends of the housing. The alignment of the splints places the centers of the fibers in alignment which provides a relatively low loss of insertion. The springs in the connector plugs urge the polished fiber end faces into intimate contact which provides relatively low retroreflection. Also available are versions of ceramic ferrule connectors containing splint tips / angle polished fiber which, when matched with similar plug plugs, provide extremely low retroreflection. Single-mode discrete fiber optic connectors contain ceramic splints that have come down in price and have improved in operation in recent years. This trend of price decreases is expected to continue as ceramic splints and ceramic alignment sleeves decrease; however, it is expected that there is a lower limit on the price of connectors for optical fibers, which is related to the lower cost limit in ferrules and ceramic sleeves. In addition, most single-mode ceramic ferrule connectors currently in use are factory installed on arrival cables or bridges or connections. These connector lead wires are usually fused or mechanically spliced into fiber optic cables. Due to the difficulty in joining fibers in ceramic splints, and then finely polishing the tips of the fibers, very few ceramic ferrule connectors are installed in the field. Therefore, the relatively high cost and lack of installation capacity in the field of ceramic ferrule connectors in a single manner has not been solved in the prior art. Another interconnect product line, particularly adapted for permanent splices, utilizes a fiber fastener element that is etched with slots of various types to provide fiber placement and alignment, and fiber entry characteristics. An example of such a product is the Fibrlok splice element, currently manufactured from a single sheet of ductile aluminum (Fibrlok is a trademark of Minnesota Mining and Manufacturing Co., assignee of the present invention). The external shape of the usually rectangular element, and is generated by preforming the element from a carrier strip. A curved focusing slot divides the rectangular element blank into two generally rectangular, equal areas or plates. At least one of these plates contains a V-shaped fiber attachment and fastening groove, which runs parallel to the curvature focusing slot. The depth of the groove V is such that a fiber of 125 μm is located in the groove and can project out of the groove at approximately 50 μm. Input slots are provided fiber-shaped funnel at each end of the V-shaped fiber slot. The opposing plate also contains funnel-shaped fiber entry slots positioned at the same distance from the curvature focusing slot so that the funnel-shaped entry slots are on the first floor. The flat Fibrlok preform is folded along the curved focusing slot until one plate is at approximately an angle of 5 to 10 degrees with respect to the other plate, which generates a structure consisting of two essentially rigid plates containing inwardly oriented fiber clamping V grooves which are joined along an edge by a hinge which operates elastically for small intervals of plate movement. When used in a Fibrlok splice, the bent V-shaped element is placed inside a plastic jacket that has end ports that are in alignment with the V-groove for positioning and fastening fiber to the element. A plastic cap fits over the outer edges of the plates or legs of the open element. The lid contains a tapered recessed area that slides down on the outside of the element legs when the lid is closed, which causes the two legs of the element to move together which holds and centers the pair of fibers located within the body. V-groove. Ductile aluminum was chosen as the material of choice for Fibrlok elements due to its low cost, its ability to be easily engraved and then folded without fractures or breaks. In addition, the ductility of the aluminum allows it to adapt more easily to the outer surfaces of the fiber without placing excessively high stress loads on the fiber during the fastening of the fiber in the V-shaped positioning groove. However, such material ductile has certain disadvantages. For example, it is difficult to repeatedly use such an element, i.e., to actuate and deactivate the clamping plates, since multiple resusions of a fiber in a ductile element do not allow the fiber to be properly embedded in itself in the alignment groove, so that the clamping forces of the fiber element and the alignment accuracy potential when reclosing repeatedly are lost. Therefore, such an element is generally not suitable for use in a connector that can be repositioned. Another weakness identified for aluminum elements is their relatively high coefficient of thermal expansion. This expansion can cause the end faces of the fiber to actually separate at higher temperatures. Although this is a minor disturbance if the connection is assembled at room temperature, it is of greater caution if the connection is assembled at very low temperatures. Another potential weakness of an aluminum element is the difficulty encountered when attempting to clean after several engraving and bending operations. When V-grooves are generated in the inlet cones in the aluminum element strip material, small aluminum flakes are often generated which adhere to the side walls and edges of the V-groove. Small particles or flakes of Aluminum are also generated along the curved focusing slot when the element is bent. If any of these flakes or aluminum particles are detached during the insertion of the bare fibers into the element, they can be attached to one end face of the fiber and block the fiber portion, which severely affects the Insertion loss Attempting to clean the V-slots of soft ductile aluminum fiber placement before bending frequently damages or scratches the V-groove. Abrasive cleaners can not be used because they are embedded in the smooth aluminum side walls of the grooves in V. The cleaning of the element after bending is virtually impossible due to the small spaces between the legs of the element. Another additional weakness of the folded aluminum element is the need for very careful control of the distance in which the legs of the element are closed during the fiber clamping operation. If the legs close too far, the hinge of the element can suddenly open and the element will not be able to hold the fibers in subsequent actions. In addition, when using fibers of different diameters in the hinge aluminum element, it is possible that one of the fibers receives less clamping force than the other, which can result in a slippage of the fiber and separation of the fiber end. Therefore, it would be desirable to design a fastener which resolves the above limitations. It would be further advantageous to incorporate such an element in a re-attached bare fiber connector having a significantly lower initial cost as compared to the ferrule connectors and providing such a connector with a single-mode use that is easily installable in field with simple procedures and at low cost, easy to use, with installation tools in the field and still provide the same or better operation than the existing ferrule connectors.

BRIEF DESCRIPTION OF THE INVENTION The present invention provides a bare fiber, splint-free connector generally comprising a receptacle and two plug-in or plug-in assemblies, the receptacle includes a fiber-clamping element that can be moved between the open and closed states, a guide tube having a bag for receiving the fastening element and cam surfaces for driving the fastening element, a base having an interior for receiving the guide tube and a lid for fixing the fastening element in the bag and for fixing the tube of guide inside the base. Each male plug assembly is adapted to match the receptacle, and includes a male plug housing, a sleeve or ring that secures a bare end portion of the fiber within the male plug housing and places the bare end of the fiber at the inlet or forward end of the male plug housing, and a cam finger attached to the input or forward end of the male plug housing and extending outwardly therefrom, located such that when the male plug housing It is inserted completely into the receptacle, the cam finger abruptly engages the cam surfaces. The securing or securing features are preferably provided in the plug-in receptacles and the receptacle for removably attaching the plug-in receptacles to the receptacle, i.e., the connector can be reattached. The bag in the receptacle guide tube can be dimensioned to allow the clamping element to oscillate within the bag, and the camming surfaces are located such that, when only one of the cam surfaces is actuated, the element The clamping member oscillates on one side of the bag opposed to a cam surface and remains in the open state, but when both cam surfaces are actuated, the clamping element is forced into the closed state. Each male plug assembly preferably includes a fiber shield located in the male plug housing and attached thereto so that the protector is free of sliding within the male plug housing, the fiber shield substantially encompassing the bare end of the male plug. the fiber when the male plug housing is removed from the receptacle, but retracts when the male plug housing is inserted into the receptacle to direct the bare end of the fiber towards the guide tube. The sleeve is preferably biased toward the forward end of the male plug housing to place a preload condition on the bare end of the fiber when the male plug housing is inserted into the receptacle. The size and shape of the cam finger is selected to drive the cam surfaces only after the bare end of the fiber has been fully inserted into the receptacle. The connector of the present invention is particularly suitable for breaking and bevel installations and, by compressive loading of the beveled fiber end faces prior to clamping, obtains superior performance in terms of both insertion loss and retroreflection. The end faces are basically flattened against each other and exclude all air between the end faces of the fiber. Optionally, the end faces can be separated at an angle to improve retroreflection. The receptacle may use a prior art fastener, but a novel element is presented which imparts additional advantages in the manufacture and use of the connector. This new fastening element has two plate members, each having a surface in contact with the fiber with at least one side of the surfaces in contact with the fiber having a fiber receiving groove formed therein. The edges of the plates are aligned and held together with a split tube spring. At least one of the plate members is preferably tapered in its thickness towards the secured edge, so that the plates are separated at the opposite ends - to the edges fastened. At least one of the plate members is provided with a slot for receiving wire and a wire thereon, generally parallel with the slot for receiving the fiber, which acts as a fulcrum to allow the plates to rotate along the length of the plate. an axis defined by the wire. The reinforcement of the splitting tube provides a precisely controlled load along the edges in the plates, which allows the opposite ends to be clamped together (inside the guide tube) by sufficient force to overcome controlled spring loading of dividing tube. The fiber receiving V-slot can be formed at the factory by another sliding fiber on the fastener, which drives the element around the fiber, deactivates or inactivates the element and then removes the fiber from the element. The plates can be constructed of a material having an appropriate coefficient of thermal expansion to avoid fracturing the end faces of the fibers during the temperature cycle. This new element provides improved performance for repeated joints, provides means for installing, holding and relieving fiber tension in its cushion coating, protects bare glass fiber and end loading of the separated / beveled fiber, and provides of guidance and alignment that ensure that the fiber end can enter the fiber alignment element without disconnection.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be better understood with reference to the accompanying drawings, in which: Figure 1 is a perspective view of one embodiment of the fiber optic connector of the present invention; Figure 2 is a side elevational view of the connector of Figure 1; Figure 3 is a top section view of the connector of Figure 1; Figure 4 is an exploded perspective view of the connector of Figure 1; Figure 5 is a side elevational view of an alternative fiber alignment and fastening element as described by the present invention and that can be used with the connector of Figure 1; Figure 6 is a perspective view of a connector storage tray or tray containing several connectors shown in Figure 1; Figure 7 is a perspective view of another connector constructed in accordance with the present invention and designed for panel mounting; Figure 8 is a perspective view of another additional connector constructed in accordance with the present invention in a duplex design; and Figure 9 is a perspective view of another additional connector constructed in accordance with the present invention, having a male plug and a female plug instead of two plugs and a common receptacle.

DESCRIPTION OF THE PREFERRED MODALITY Now with reference to the figures, and in particular with reference to Figures 1 and 2, a mode 10 of the optical fiber connector of the present invention is shown. The connector 10 is generally constituted by a housing or receptacle 12 having its open ends which receive, respectively, two male plug assemblies 14 and 16. In the embodiment shown, the male plug assembly 14 is designed for an optical fiber 18. at 250 μm, while the male plug assembly 16 is designed for an optical fiber 20 of 900 μm. Although the connector 10 is suitable for interconnecting different fibers, it is of course equally useful for connecting fibers of identical size. The connector 10 can be used for multiple mode single mode fibers. The details of the construction of the receptacle 12 and the male plug assemblies 14 and 16 are shown in Figures 3 and 4. The male plug assembly 14 includes a tubular fiber shield 22, a protective spring 24, a sleeve 26, sleeve housing 28, a sleeve ring 30, a sleeve spring 32, a male plug body 34, a male plug body spring 36 and a male plug housing 38 and a tension sleeve sleeve 40 (which does not it is shown in figures 2 and 3). All of these components, except compression springs, are preferably constructed of a durable injection moldable polymer, such as polyethersulfone.

(PES), polycarbonate (commercially known as LEXAN), polyarylsulphone (sold by Amoco RADEL), polybutylene terephthalate (PBT), polyphenylene sulfide (PPS), polyetheretherketone (PEEK), polyether imide (PEI), liquid crystal polymers or butadiene and styrene acrylonitrile.

These parts fit together in the sequence illustrated in Figure 4. The fiber shield 22 slides in and out of the male plug body 34 and is biased by the spring 24 towards the inlet end of the plug assembly 14, i.e. , towards the receptacle 12. The projections or tabs 42 project from the skirt of the fiber shield 22 to engage the slots 44 formed on the sides of the plug body 34 to prevent the shield 22 from completely escaping from the plug body 34. male and to prevent the protector 22 from rotating. The forward tip of the fiber shield 22 has a wall with an orifice that is concentric with the outer diameter of the forward tip, and approximately 0.05 mm (0.002") larger than the diameter of the fiber. slide through this and accurately positioned as the shield 22 moves toward the male plug body 34 when the male plug assembly 14 is inserted into the receptacle 12. The narrow alignment of the bare fiber end with the plug-in feature Clamping prevents damage to the bare end of the fiber during insertion. During the removal of the male plug the force of the protector ensures complete retraction of the bare end of the fiber in the protector before any removal of the receptacle protector, protecting the bare end of the fiber. The 250 μm fiber buffer is clamped in the three-jaw sleeve 26 which fits inside the sleeve housing 28. The sleeve 26 and the sleeve housing 28 can be axially moved approximately 1.3 mm (0.050") inside the body 34 of the male plug with the spring 32 which provides a preload of the sleeve assembly towards the front tip of the male plug assembly , about 0.9 N (0.2 lb.) The male plug housing 38 snaps onto the outside of the male plug body 34 and slides relative to the male plug body 34 against the other preload spring 36. The sleeve 40 provides relief of the bending tension of the fiber damper exiting the rear end of the male plug 16. The male plug assembly 16 includes a similar fiber protector 46, a protective spring 48, a male plug body 50, a spring 52 of male plug body, a sleeve 54, a male plug housing 56 and another tension relief sleeve 58 (not shown in Figures 2 and 3.) All of these components (again, as shown in FIGS. except compression springs) are preferably constructed of an injection moldable polymer. As with the male plug assembly 14, the fiber protector 46 is retained in the male plug body 50 by externally projecting snap-fit characteristics, and allowed to slide but not rotate. The spring 48 preloads the shield 46 towards the inlet end of the 900 μm plug assembly, ie towards the receptacle 12. The sleeve 54 fits within the plug body 50 and is clamped over the fiber cushion of 900 μm when the sleeve has been completely axially accommodated within the support of the male plug body 50. The male plug housing 56 also snaps onto the male plug body 50 for restricted sliding movement, and the spring 52 provides a preload between the male plug housing 56 and the male plug body 50. Male plug assemblies have features on the internal coupling components that allow a complete factory assembly of the male plug units to reduce field part count and maximize ease of installation. These characteristics allow the installer to easily repair the fiber end as prescribed and insert it into the male plug assembly and, by means of a small tool, completely retract the protector which activates the sleeve and fixes the fiber to the male plug assembly, so it provides a termination to the fiber for connection. In the case of fiber rupture, these features provide means for deactivating the termination by uncoupling the sleeve in a mounting tool and allowing the fiber to be removed. The fiber end can then be prepared again and reinstalled as previously established. The receptacle 12 includes a phase 60, a lid 62, an internal guide tube 64 and a clamping element 66. Base 60 and cover 62, together, form the outer portion of the receptacle and can be constructed of any durable injection moldable polymer. The guide tube 64 can also be formed of an injection moldable material. The guide tube 64 snaps in the center of the base 60 of the receptacle and has circular end ports that are aligned with the groove V in the clamping element 66 when the element is installed in the guide tube 64. The fastening element 66 is preferably etched from a metallic material and utilizes V-groove technology similar to that shown in U.S. Patent No. 5,189,717. The fastening element 66 consists of two generally flat plates which are joined along their long edge by an elastic joint. The plates normally open slightly around the hinge axis, preferably at an angle of about 1 to 8 degrees. The inner surface of one of the plates has a fiber alignment slot V and half of the input fiber (a funnel-shaped print) placed at each end of the V-shaped slot, where it leaves the outer edge of the screen. plate, at a distance from the joint about 1/4 of the width of the plate. Slot V is parallel to the joint. The inner surface of the other plate is generally flat except for one half of the fiber entry funnel which is aligned with the details of the front on the opposite plate. The fiber entries ensure that the fiber is guided in a regular manner in the V-groove in the element when the male plug assemblies 14 and 16 are inserted in the connector receptacle. The V-slot for fiber clamping and alignment is engraved to a depth in the sinking plate so that the outer surface will project out of the V-groove at approximately 20% of its diameter. Therefore, when the plates or legs of the element are in their open or separated position, there is sufficient space between the flat surface of one of the plates on the sides of the V-groove in the other plate to allow the fiber to be inserted. at the ends of the V-groove, and slip along the V-groove without significant resistance. The fit between the V-groove and the opposing plate surface is not large enough, however, to allow the fiber to leave the V-groove, or for the two beveled fibers to overlap when inserted from opposite ends of the V-groove. the V-groove. When the upper edges of the two plates opposite the joint are pushed together, the gap between the opposite plate and the V-groove becomes smaller. In its relaxed (non-driven) mode, the two legs of the element are separated sufficiently to allow the optical fiber to be inserted into the opposite ends of the V-shaped slot so that the joint between the fibers is located approximately in the center of the element. When the element is actuated or closed (as explained below), the legs of the element are pushed together around the elastic joint, and the fibers are clamped in the V-groove. It is also possible to provide an element in which slots are provided to receive the fibers in both plates. It may be advantageous to make these grooves by fastening a single fiber therebetween at the factory to provide a more uniform groove surface finish and fiber alignment. Multiple slots can be formed for use with a fiber tape. The fiber clamping and alignment element 66 illustrated in Figure 4 is designed to be fabricated from a thin sheet of metallic or polymeric material using, for example, etching, preforming and bending processes. This element is very similar to the element used in the optical Fibrlok fiber splice. Nevertheless, it is possible to provide other designs, so that an element consisting of two separate plates that are joined by a spring tube, as detailed below. The fastening element 66 is fixed to a bag 68 in the upper part of the guide tube 64. Flexible hinged fins are provided which contain cam surfaces 70 and 72 at the upper outer edges on both sides of the bag 68. The cam surfaces make corresponding contact with the cam surfaces on the drive fingers 74 and 76 which project from the inlet ends of the male plug housing 14 and 16, respectively, as the male plugs are pushed into the receptacle. The cam surfaces of the male plug fingers 70 and 72 contact the outside of the cam fins 70 and 72 of the element and push the fins together when both male plug assemblies 14 and 16 have been fully inserted into the receptacle 12. In its open position, there is sufficient space between the fins for the element to rotate or oscillate from one side to the other, preferably through an angle of approximately 5 to 10 degrees. If only one plug assembly is inserted, the actuator finger from the plug housing pushes the corresponding cam tab towards the center line of the bag 68, since the other tab does not contact anything, the element 66 oscillates away on one side of the bag 68 and thus the element 66 does not close on the fiber or hold it in the V-groove. However, when it is inserted into another male plug, its actuator finger pushes the opposite cam flap of return to the center line of the bag 68 and, because the element does not forcefully touch both cam fins, the plates of the element close and hold the fibers that are in the V-groove. Therefore, All of the necessary operations of fiber protection, guidance, centering and restraint occur during the process of insertion and removal of the male plug. The fixing or securing features on the exterior of the receptacle base 60 and the receptacles 38 and 56 of the plug removably secure the male plug assemblies 14 and 16 to the receptacle 12. The insertion of the male connector plugs into the receptacle causes the fins on the sides of each male plug housing 38 and 56 to slide under the locking portions of the release latches with the thumbs. When the fins clear the bolt portions, they move back together and retain the male plug receptacles of the connector in position within the receptacle. To release each male connector plug, the thumbscrews are presented to the mating plug body of the connector, decoupling the latch portions of the tabs on the male socket housing and allowing the male housing and plug bodies of the male connector. Connector will move backward, out of the connector receptacle. The cover 62 of the receptacle fits under pressure on the base 60 of the receptacle by means of the clamping fingers 78, the capture element 66 and the tube 64 within the base 60 and complete the connector receptacle assembly. The cap 62 also contains surfaces and wall structures 80 that support the opposite non-cam side, of the drive fingers 74 and 76 to prevent the fingers from flexing outwardly from the contact and camming force for close the fastening element 66. This embodiment of the invention allows the lid to be removed for replacement of the fastening element 66 in the case where, for example, a fiber is broken or by dust contamination in the element. A small tool may be required to press the clamping fingers 78 together so that they can be uncoupled from their mating holes in the base 60, so as to release the cover 62. The receptacle 12 and the male plug 14 can be provided with flanges 82 and 84 (figure 1), respectively, to provide a better holding action for the thumb and fingers. Referring now to Figure 5, there is shown a novel design for a fastening element 90 which has several advantages with respect to the single piece element 66, divided mainly by the fact that the element 90 can be constructed from a wide variety of materials, particularly those with greater resistance to abrasion and hardness compared to the one-piece bent element 66. The new element 90 is generally constituted by two substantially flat rectangular plates 92 and 94, which are slightly tapered along an edge 96, 98. These edges are shown in the same plane with each other and, although it is preferred, not necessarily they are perfectly aligned, but it is sufficient that the effective edges of the plates are generally aligned to effect the turning action described below. Shallow V 100 and 102 slots are formed in this tapered area on each plate. On the flat rear side of the element plates and the tapered end, grooves 104 and 106 of greater depth are formed slightly closer to the edge of the tapered end of the element. One of the plates 92 of the flat element has a V-shaped fiber of a positioning and holding groove 108 with a V-shaped entry hole in each end of the V-groove. The plate of opposite element has a pair of 110 fiber entry slots formed in half cone companions. The plates 92 and 94 are held together with a split tube spring 112 the legs of which fit into the slots 104 and 106 on the rear side of the plates 92 and 94. As mentioned above in relation to the element 66, Two slots can be formed, one on each plate, instead of just one slot with a flat support surface. The tube spring 112 is preferably made of a metallic material such as beryllium copper or stainless steel, held open slightly to fit over the element plates and into the placement slots. This design provides a slight pre-loaded condition force that occurs between the plates 92 and 94. An alignment and rotation wire 114 can optionally be inserted into the coupling V-notches 100 and 102, located in the thickest section of the coupling. the tapered region of the element plates. The wire 114 functions as a fulcrum pivot point and keeps both plates 92 and 94 properly aligned when the outer edges of the plates opposite the tapered sections are forced together during the fastening of a fiber. In this open condition, the tube spring pushes against the outside of each plate and urges the plates to be in contact with the articulation wire 114, and also along the edge portion the thin portion of the tapered section of each license plate. In the open position, the inner edges of the plates 92 and 94 are preferably located at an angle of about 5 degrees with respect to one another. This amount of aperture is large enough to allow optical fibers of 125 μm from opposite edges of the plates to be easily inserted into the V-slot 108 for fiber placement. The fibers have approximately 15 to 25 μm of free space between both sides of the V-groove, and the flat surface of the opposite plate coupling. This amount of free space ensures that the end faces of the fibers (particularly the bevelled end faces) are brought into contact in the V-groove without allowing the fibers to pass each other in the central part of the V-groove during the insertion. The input characteristics of the fiber formed in a half-funnel in the element plates ensures that the fibers easily enter the V-groove during the insertion process. When used in the connector 10, the bevelled separated fibers are inserted from opposite ends of the element 90, and their end faces contact each other approximately in the central part of the element. Preferably, the fibers are pushed towards each other with a longitudinal load of about 0.9 N (0.2 pounds), which causes the reduced area of the separated fiber end * to be oriented and elastically flattened towards each other, which reduces the loss of insertion and retroreflections. To clamp the fibers in the V-groove, the non-tapered edges of the element plates are pushed together (as with element 66) which causes plates 92 and 94 to initially rotate around the pivot wire and cause the tapered edges of the elements move out of contact. At some point as the element plates move closer together, the space between the V-groove of fiber fastener and the fibers is reduced, and the fibers are clamped. The additional closure of the upper parts of the element plates finally causes the plates to be in full contact with the fiber, and to move out of contact with the hinge wire. The clamping force in the tube spring now precisely controls the clamping forces of the fibers. Theoretically, any level of clamping force on the fibers can be accurately provided by sizing the tube spring to provide this force; a force of approximately 44.5 N (10 pounds) is preferred. If the fibers are of a slightly different diameter, the tube spring is advantageously elastically deformed a little more at one end than the other to accommodate misalignment in the fiber diameter. Therefore, the element 90 is particularly useful in bare fiber connectors such as those of the present invention which use axially pre-cut and bevelled fibers. The fastening element 90 has numerous advantages over all existing aluminum elements especially when used in bare fiber connection applications. In the current Fibrlok element, the hinge and the element are integral and made of the same material. In forming this hinge in the current element requires that the material of the element initially be very ductile and then must be capable of being hardened by work to provide the properties of elastic hinge over a very short range of movement. This limits the number of materials that are available to manufacture the element in this design. In the new two-plate element design with the tube spring and the hinge wire, the element plate material can be selected based on the most desirable properties for manufacturing and removing the surface particles, for strength to the abrasion and hardness to avoid fiber impressions in the V-groove area for ease of cleaning, for low coefficient of thermal expansion (less than 12 x 10"S inches / inches / ° F), and for resistance to chemical attack With this design freedom, a broader range of element materials can be considered Some materials which may have desirable properties for element 90 include stainless steel, titanium, ceramic materials, glass and possibly some low CTE polymers of high stiffness The element 90 may be easier to manufacture than the existing element because the required hinge formation and folding process is eliminated, due to the fact that e less material must be moved in the formation process and because the fins of the element will be more robust and easy to clean. It is expected that the prepared tube spring will provide more uniform fiber clamping forces even when the plates are closed over a wider range of displacements. The tube spring 112 has the ability to provide the desired fiber holding forces on the fiber even if the element closes more than required. In the prior art design, an excess closing of the element can cause the hinge to stretch or distort which initially produces a very high fiber holding force. In subsequent closures, the distorted hinge can not provide adequate forces to hold the fibers in the V-groove. Although the new element concept has been designed primarily for connection applications, it can also be useful in splice applications, ie , for the permanent interconnection of optical fibers. The previous aluminum element in the Fibrlok joints changes its length with variations in temperature. This is considered to cause the end faces of the fiber to separate and join slightly as the element changes in length during the temperature cycle. The back and forth movement at the end faces of the fiber is also considered to cause the index coupling gel used in the splices to flow around the ends of the fibers and possibly generate air bubbles by particular transport of dust in the gel between the fiber cores and block part of the transmitted light. Therefore, an element material with a very low coefficient of thermal expansion would be beneficial to eliminate the potential movement of the gel and the associated formation of gas bubbles or the transport of dust particles between the fiber and the end faces in the region. of core fibers. There have also been cases in which the initial flexibility of the assembled prior art splices has been reduced due to dusts or manufacturing residues in the V-groove for fastening the fiber to the element element thereof. An element, such as element 90, constructed of a material that can withstand a more rigorous cleaning without damage to the V-groove, would increase the initial mounting performance or the percentage of low loss splices produced. Due to the wide range of element plate materials that are possible with the new design element, it is expected to provide a "cleaning" element for splicing. The connector of the present invention can be used in several different applications. Figures 1-4 show a connector 10 adapted for tray mounting applications with both fiber plugs inserted into the ends of the receptacle. In this embodiment, the connector receptacle 12 does not have an externally projecting mounting flange, but contains an internal cavity that snaps on a mounting post 116 on a flat plate such as would be found on the bottom. of a storage handling tray / connector fiber 118, as shown in Figure 6. The outer shape of this tray assembly connector mode has been kept as small as possible so that the connectors are placed adjacent to each other. yes and occupy the minimum amount of volume. The tray 118 can contain up to four connectors. Posts 116 are hollow so that a bolt-like tool can be inserted through the hollow portion to lift the connector away from the pole and out of the tray for easy access to an individual connector. This system is particularly suitable for fiber home applications. In the design illustrated in Figures 1-4 and 6, the 250 μm male plug is spring preloaded, but the fiber in the 900 μm plug is mounted on the male plug solidly, and will not be required to be spring loaded. Although the two male plugs of Figures 1-4 are of different designs, they can be of the same design insofar as at least one male plug contains means for preloading one fiber against the other. The device preferably bears the terminal end faces of the fibers to a compressive load of at least 0.09 N. The interior of the tray 118 may be provided with one or more coils for storing excess loose fiber. Very thin coils can be provided with stacking on a common post molded into the floor of the tray (not shown) so that the individual fibers can be rolled separately onto the coils and later on can be accessed by removing the coils above the desired fiber, without manipulating (and possibly damaging) other individual fibers. Figure 7 illustrates another embodiment 120 of the connector of the present invention, configured with an externally projecting mounting flange 122 having mounting holes 124. The connector 120 is mounted on a connector panel (not shown) that is part of the fiber distribution equipment. The panel mounting connector 120 can be placed in central gaps that allow easy access of the fingers to individual connectors without disturbing adjacent connectors or their fibers. Figures 1-4 and 6-7 illustrate designs according to the present invention which are useful for connecting discrete fibers mounted on individual male connector plugs. Figure 8 illustrates another design in which two discrete connectors similar to the connector 10 have been unified to create a duplex fiber connector 130. The male plugs 132 and 134 of the connector in the duplex connector 130 contain dual spring-loaded fiber projectors, fiber preloading means (springs) and fiber fastening means (sleeves). The duplex connector housing or receptacle 136 contains two alignment elements and two sets of input ports for internal fiber guide portions of the duplex connector male plugs. The fiber spacing for this connector design is preferably about 8 mm. The designs in figures 1-4 and 6-8 are designs of MALE PLUG-ACCOMMODATION-MALE PLUG. NeverthelessIt is also possible to design a connector according to the present invention using the same interconnection methods as a design of MALE PLUG-MALE PLUG-MALE PLUG, but which would have one of the plugs permanently integrated to the central housing. This style of connector 140 is referred to as a MALE PLUG and FEMALE PLUG design and, as illustrated in Fig. 9, it generally comprises a single male plug 142 similar to the male plug 14 or 16, and a female plug 144 containing an element 90 clamping and alignment and functional parts of the other plug all combined in a single unit. The connector 140 is particularly useful for those applications in which the fiber rearrangement occurs only on one side of the connector (at the front of the panel, for example). The fiber on the other side of the connector (behind the panel) is permanent and should not be rearranged. The combination of one of the plugs with the alignment housing to create a female connector reduces the count in the connector part, the size of the connector and potentially the cost of the connector. As used in the claims, the term "receptacle" encompasses both the male double plug receptacle 12 and the female plug 144. The use of any of the above connectors is linear. When the fibers have been beveled, cleaned and inspected, they are installed in the male connector plugs. The beveling can be carried out by for example, the use of the tools described in the application for US patent Serial No. 08 / 122,755. This is done by first installing one of the vacuum connector plugs completely assembled (not containing a sheath) in a small drive tool or device. This tool (not shown) will provide means to: 1) guide the prepared fiber to the connector plug, 2) provide a length stop for the tip of the fiber so that there is the correct amount of bare glass fiber inside the male connector plug, and 3) drive the inner sleeve to the male plug of the connector in order to hold it on the Fiber cushion and secure the fiber in the male connector plug without the use of adhesives or fastening tools. The prepared fiber is inserted through the fiber curvature tension relief sleeve, and the sheath slides down the fiber and out of the path. A fully assembled male connector plug is then loaded into the installation tool, and the broken and beveled end of the fiber is inserted into the rear end of the male connector plug. The fiber is pushed towards the protective fiber end of the connector until the beveled edge end of the fiber contacts a tension gauge located at the front of the slightly retracted fiber shield. When the fiber is in the desired position, the technician operates a handle on the installation tool which axially urges the sleeve towards the sleeve housing, and permanently clamps the fiber damper on the connector plug body or on the sleeve assembly loaded with a spring, based on the type of male plug style being assembled. It is considered preferable to use the connectors of the present invention together with optical fibers whose end faces have been bevelled. The bevel angle is preferably about 45 °, that is, an included angle of about 90 °, although the included angle may be in the range of 30c-160 °. The beveling leaves a flat central area on the end face of the fiber, with a preferable diameter of between 20 and 120 μm. The central portion may be inclined, that is, be non-orthogonal to the fiber axis, to reduce retroreflections. The male connector plug is removed from the tool and can be directly attached to any resistance member (Kevlar strands) directly to the male plug body of the 900 μ style connector plug using standard clamping sleeves, etc. The design of the male connector of the 250 μm connector can also be used with reinforced cable types, but the body of the male plug must be extended to allow a bend in the fiber between the place where it is fastened in the spring loaded sleeve and the rear end of the connector. This region of fiber curvature is necessary because the spring-loaded sleeve is pushed back into the body of the connector against the preload spring of 0.9 N (0.20 lb.) to create the desired level of compressive preload at the ends of the sleeve. fiber. A larger male plug body (not shown) will have to provide a sufficient terminal space to accommodate the additional fiber length, such as a fiber elbow, when the fiber is rigidly attached to the back of the connector male plug, and then push back into the connector during insertion of the male plug into the housing. The final step in the fiber installation procedure is to slide the tension release sleeve back up the fiber and press it onto a hollow post through which the cushioned fiber passes on the back of the connector plug body . As indicated above, the arms of the shock absorber sleeve can be uncoupled and the fibers can be removed in the event that a fiber breaks inside the connector and needs to be replaced or reattached and beveled. The male connector plugs are then ready for insertion into a receptacle or female connector socket. The first male plug (for example 14) is inserted into the receptacle until the fiber producer enters the interior and exits in the socket in the guide tube 64. A continuous movement of the male plug causes the fiber protector to slide backwards in the male plug body against the compression spring, and the beveled cut fiber enters the V-groove in the element. The additional thrust of the male plug into the housing results in the fiber continuing to slide on the element until the tip of the fiber is slightly beyond the center of the element. At this point, the plug male connector body moves in the same plane against the front face of the alignment receptacle. Continuing to push the male plug cover of the connector causes the cam finger at the front of the lid to raise the element drive flap and attempt to close the element on the fiber. If the other male plug is not installed on the opposite side of the receptacle, the fiber fastener will not only oscillate on one side in the bag 68, and the beveled tip fiberglass in the element is not clamped. The male plug housing (for example 38) is pushed into the receptacle until it is secured to one of the receptacles that engage the tabs on the sides of the male plug housing, locking them in place. When the other male plug (for example 16) is inserted at the opposite end of the receptacle, its fiber guard comes out and guides the fiber towards the end of the element 90. The continued movement of the opposite male plug of the housing pushes its fiber downwardly. from the V-groove in the element towards the end of the other fiber. When the two fiber ends make contact with each other in the slot V, the compression spring pushing against the sliding fiber sleeve in one of the male plugs begins to compress and the tip of the fiber is preloaded to the desired load. The preloading of the fibers continues until the plug body of the remaining connector male plug moves in the same plane against its end of the alignment receptacle. At this point, the fibers are preloaded against each other in the V-groove of the element, but are not fastened. The male plug housing of the other plug does not continue to move which causes the drive finger to move in the housing center and the cam of the element is closed over the pre-loaded stationary fibers. When the latch of the other male plug engages, the connection between the fibers is completed. The 900 μm male plug 16 has been designed with an optional pull-pull feature that operates between the fingers of the male plug body 50 and the guide body 64. These components have flexible coupling fingers that engage with each other when the male plug body fully enters the 900 μm end of the receptacle. These fingers fix the plug body to the alignment receptacle, and make the 900 μm male plug end of the pull-proof connector. This draw-pull-proof feature can also be provided at the other end of the connector, but the male plug body must be elongated to accommodate a bend or elbow in the fiber between the spring-loaded sleeve and the preloaded assembly in the Rear end of male connector plug. Although the invention has been described with reference to specific embodiments, this description does not mean that it is constructed in a limiting sense. Various modifications of the described modality, as well as alternative embodiments of the invention, will become apparent to persons familiar with the art upon reference to the description of the invention. Therefore, it is considered that such modifications can be made without departing from the spirit or scope of the present invention as defined in the appended claims. It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates. Having described the invention as above, property is claimed as contained in the following:

Claims (20)

1. A device for interconnecting two naked optical fibers, characterized in that it comprises: a receptacle having a clamping element that can be moved between the open and closed states, the clamping element is adapted to fix the bare ends of the fibers in optical connection in the closed state; a first plug or plug assembly having a first optical fiber thereon, a terminal end face of the first optical fiber is bevelled, the first plug assembly includes: a first plug socket having a first and second ends, a first sleeve means for securing a portion of the first fiber within the male plug housing and for positioning the first fiber proximate the first end of the first male plug housing, and a first means for biasing the first sleeve means towards the first end of the first male plug housing for placing a preloaded condition on the first fiber when the first male plug housing is inserted into the receptacle; and a second plug assembly having a second optical fiber thereon, a terminal end face of the second fiber is also beveled, the second plug assembly includes a second plug socket having first and second ends , a second sleeve means for fixing a portion of the second fiber within the second male plug housing and for positioning the second fiber proximate the first end of the second male plug housing so that the terminal end faces of the first and second one fibers are maintained in compressive coupling.

2. The device according to claim 1, characterized in that at least one of the terminal end faces of the first and second fibers is cut at a non-orthogonal angle with respect to the axis of the fiber.

3. The device according to claim 1, characterized in that the terminal end faces of the first and second fibers are subjected to a compressive load of at least 0.09 N.

4. The device according to claim 1, characterized in that each of the first and second fiber end faces has a bevel angle included in the range of 30-160 °.

5. The device according to claim 1, characterized in that each end of the first and second fiber faces has a flat central area with a diameter in the range of 20 μm to 120 μm.

6. The device according to claim 1, characterized in that the first assembly of the male plug and the receptacle additionally have means for holding the first and second fibers in the clamping element only after the first and second fibers have been coupled to each other. Compressive way

7. The compliance device. with claim 2, characterized in that the end faces of the first and second fibers are subjected to a compressive load of at least 0.09 N.

8. The device according to claim 7, characterized in that each of the end faces of the first and second fibers have a bevel angle included in the range of 30 ° -160 °.

9. The device according to claim 8, characterized in that each of the first and second fiber faces has a flat central area with a diameter in the range of 20 μm to 120 μm.

10. A device for interconnecting two optical fibers, characterized in that it comprises: a receptacle having a clamping element that can be moved between the open and closed states, the clamping element is adapted to fix the bare ends of the fibers in optical connection with the closed state; at least one male plug assembly has a first optical fiber thereon, the male plug assembly includes a male plug housing having a first and second endsmeans for securing a portion of the first fiber within the male plug housing and for positioning the first fiber next to the first end of the male plug housing, and means for biasing the fixing means towards the first end of the male plug housing for connecting a preload condition on the first fiber when the male plug housing is inserted into the receptacle so that a terminal end face of the first fiber can be compressively coupled with a terminal end face of a second fiber located at the fastening element; and means for fixing the fastening element, and in this way fastening the fibers in the fastening element only after the first and second fibers have been compressively coupled.

11. The device according to claim 10, characterized in that the first optical fiber has a beveled terminal end face.

12. The device according to claim 11, characterized in that the terminal end faces of the first and second fibers are subjected to a compressive load of at least 0.09 N.

13. The device according to claim 12, characterized in that each of the first and second fiber end faces has a bevel angle included in the range of 30 ° -160 °.

14. The device according to claim 13, characterized in that each of the first and second fiber end faces has a flat central area with a diameter in the range of 20 μm to 120 μm.

15. The device according to claim 14, characterized in that at least one of the terminal end faces of the first and second fibers is cut at a non-orthogonal angle with respect to the axis of the fiber.

16. A method for interconnecting two naked optical fibers, characterized in that it comprises the steps of: separating a first optical fiber to provide an end face; fixing the first optical fiber in a first male plug assembly, the first male plug assembly includes a first male plug housing having first and second ends, the first means for securing a portion of the first fiber within the first housing male plug and to place the first fiber next to the first end of the first plug socket, - separate a second optical fiber to provide an end face; fixing the second fiber optic in a second plug assembly, the second plug assembly includes a second plug housing having first and second ends, the second means for fixing a portion of the second fiber within the second housing plug for placing the second fiber next to the first end of the second plug housing, and means for biasing the second fixing means towards the first end of the second plug housing for placing a preload condition on the second fiber when the second plug housing The male plug is inserted into a receptacle so that the end faces of the first and second fibers can be retained in a compressive coupling therein; and inserting the male plug assemblies into a common receptacle having a clamping element for receiving the optical fibers in such a manner that the end faces of the first and second fibers are first compressively loaded before the clamping element acts.

17. The method according to claim 16, characterized in that it additionally comprises the steps of: bieelar the cut end face of the first optical fiber at a bevel angle included in the range of 30 ° -160 °; and beveling the cut end face of the second optical fiber at a bevel angle included in the range of 30 ° -160 °.

18. The method according to claim 16, characterized in that the fastening element is constructed of a ductile material, and additionally comprises the step of forming a fiber receiving groove in the fastening element by the sub-steps of: sliding a third fiber in the fastening element; actuating the fastening element around the third fiber; deactivate the fastening element; and remove the third fiber from the fastening element.

19. The method according to claim 16, characterized in that the cutting steps are carried out by cutting both end faces of the first and second fibers at an angle not orthogonal with respect to the axes of the fiber.

20. The method according to claim 17, characterized in that: the end faces of the first and second fibers are subjected to a compressive load of at least 0.09 N; and each of the first and second fiber end faces has a flat central area with a diameter in the range of 20 μm to 120 μm. SUMMARY OF THE INVENTION A device for interconnecting bare ends of two or more optical fibers is provided using a common receptacle having a fiber fastener in which the cam surfaces for actuating the element, and at least one plug have a cam finger to attach one of the cam surfaces. The cam surfaces are located such that, when only one of the cam surfaces is actuated, the clamping element swings to one side of the package opposite a cam surface and remains in the open state, but when both surfaces are actuated of cam, the clamping element is driven to the closed state. The plug includes a fiber-free fiber guard within the plug housing, which substantially encompasses or surrounds the fiber end of the fiber when the plug housing is removed from the receptacle but retracts when the plug housing is inserted into the plug. receptacle for directing the bare end of the fiber towards the guide tube. A fiber sleeve deflects the terminal end of the fiber towards the front end of the plug to place a preload condition on the bare end of the fiber. The connector is particularly suitable for break and bevel installations. Preferably the receptacle uses a novel echeloning element having two plate members with a surface in contact with the fiber, at least one of the surfaces in contact with the fiber has a slot for receiving the fiber. The edges of the plates will be aligned to keep together with a splice spring. At least one of the plate members is provided with a slot for receiving wire and a wire therein which acts as a fulcrum to allow the plates to rotate along an axis defined by the wire. The divider tube spring provides a controlled load with precision along the edge of the plates, which allows the opposite ends to be held together (inside the guide tube) by sufficient force to overcome the controlled load of the spring of dividing tube.