Field terminable lc format optical connector with splice element

Background of the invention

Field of the Invention

The present invention relates to an optical connector.

Description of the related state of the art

Mechanical optical fiber connectors are already known in the telecommunications industry. For example, LC, ST, FC and SC connectors are widely used.

LC format connectors were developed in the early nineties by Lucent in the form of a small optical connector. These connectors have about half the dimensions compared to other standard connector formats. The smaller size allows for a higher packing density in distribution boxes, providing savings for the main system operator and the data centers it uses.

The original LC connectors were made by inserting an uninsulated optical fiber into a ferrule (sleeve with a hole) and gluing the optical fiber, usually using epoxy glue. Conventional designs of LC connectors and information on their manufacture are described in US Patents US 5,461,690; US 5,579,425; US 5,638,474; US 5,647,043; US 5,481,634; US 5,719,977 and US 6,206,581.

Very recently, the LC joint was developed using hot melt glue instead of epoxy, described in US Patent No. 7,147,384.

Conventional LC connectors require multi-step polishing, which must be controlled in order to achieve a high degree of smoothness at the end of the fiber and ferrule, while maintaining the correct ball radius on the ferrule side, as well as maintaining a certain ferrule length. The degree of care required to prepare such a joint is compounded more with an AFC (polished at an angle) joint.

In light of such requirements, such conventional connectors are not very well suited for field installation. As mentioned above, glue is required to mount standard LC connectors to the optical fiber. The field preparation procedure can be uncomfortable and time consuming.

EP2 279 441

In addition, polishing after assembly requires a high level of skill from the employee.

Hybrid optical welded joints are also known, as described in Japanese patents JP Application No. 3445479, JP application No. 20045 210251 (WO 2006/019516) and JP application No. 2004-210357 (WO

2006/019515). However, these hybrid welds are not compatible with standard connector formats and require meticulous field assembly. Laying and directing a multitude of small connector components can lead to incorrect assembly, resulting in poorer operating characteristics or a greater chance of damaging the optical fiber.

A recent US publication no. 2007/0104425 A1 describes a fiber optic connector that has a pre-polished ferrule tip terminated in the ferrule and connected to the fiber in the field by mechanical welding. This connector, marked with the NPC symbol, is currently available on the market from the 3M Company. Available small format connectors include Pretium LC (available from Corning), Fast LC (available from Fujikura), Opticam LC (available from Panduit) and Lightcrimp (available from Tyco).

Publication JP 2007-279514 A discloses a tool for optical connectors, also optical connectors equipped with a tool, which is used to open and close elements separated into two halves of the optical connector clamping section and fixes a pair of optical fibers between these elements by inserting and removing the insert between these elements conical.

US Publication No. 2005/0238292 A1 discusses field-installed fiber optic connector including housing, ferrule, ferrule holder, fiber welding holder, connecting components, and cam element.

US Publication No. 2006/0093300 A1 describes a fiber optic splitter terminal assembly that can be easily and reliably terminated in the field using simple tools, allowing field fiber optic cables to be displaced or replaced if joining is not accepted due to the operating characteristics.

Summary of the Invention

In accordance with one aspect of the present invention, there is provided an LC format optical connector for optical fiber connection as defined in independent claim 1. The LC format connector comprises a body adapted to be connected to

EP2 279 441 a LC type socket, the body comprising a LC format housing and a frontal plane, the first flexible latch located on the surface of the housing, adapted for insertion into the LC socket, the first flexible latch protruding from the frontal plane, and a shaft adapted for insertion the outer surface of the housing on its first section and having the mounting structure positioned on its second section. The LC format connector also includes a sleeve body located in the body and attached between the outer casing and the shaft, where the sleeve body includes a fiber tip located in the first section of the body, the fiber tip comprising a first optical fiber mounted in the ferrule and having a first end near the end plane ferruli and the second ending. The sleeve body further comprises a mechanical welding assembly disposed in a second section of the sleeve body, the mechanical welding system being adapted to weld the other end of the fiber tip to the second optical fiber. The LC format connector further includes a lever coupled to the outer surface of the body stem, the lever including a second latch that extends toward the frontal plane where the second latch portion overlaps the first latch portion, the second latch engaging the first latch upon actuation first latch by applying pressure.

In one aspect, the LC format optical connector of claim 1 includes a protective fiber sleeve coupled to the end of the housing to limit lateral displacement of the second optical fiber, the protective sleeve having its first section located between the shaft and the lever.

In another aspect of the invention, the lever further includes an internal coupling mechanism for coupling the LC format fiber optic connector to the second LC fiber optic connector. In one aspect, the connector mechanism includes a dovetail protrusion formed on the surface of the first side of the trigger lever and a corresponding gap formed on the opposite surface of the lever, the gap being designed to slide and play slackly with the dovetail portion of the second LC optical fiber connector .

In yet another aspect, the LC format fiber optic connector includes cable identification labels disposed on opposite outer sides of the shaft.

EP2 279 441

In another aspect of the invention, the second latch comprises an activating element that overlaps the section of the first latch, and is constructed so that it can be pressed by finger force. In one aspect, the latch activating element comprises a slung edge section that protrudes from the first side of the activating element and a slung edge section protruding from the opposite side of the activating element

In another aspect of the invention, the LC-format fiber optic connector further comprises a buffer clamp constructed on a third section of the sleeve body, wherein after switching on the buffer clamp adapted to block at least a section of the buffer coating of the second fiber, and the sleeve activating the buffer clamp is constructed so that it can be pushed on the outer surface of the third section of the sleeve body and slide the buffer clamp on.

In another aspect, the first latch and the second latch are formed as a single, integrated structure engaging the housing with the lever.

In another aspect of the invention there is provided a set of plurality of LC format fiber optic connectors, wherein such a set of multiple LC format fiber optic connectors includes the LC fiber optic connector described above and at least a second LC fiber optic connector. The second LC fiber optic connector includes a second body, second sleeve body and second lever, the second lever having a second coupling mechanism which includes a dovetail protrusion and a corresponding slot, wherein the dovetail protrusion of the second LC connector is inserted into the corresponding slot of the first fiber optic connector LC format.

In one aspect, the set of multiple LC fiber optic connectors is a LC duplex fiber connector.

The LC-format fiber optic connector for terminating the optical fiber cable may further include a body consisting of an LC-format external housing and a frontal face adapted for insertion into the LC socket. The flexible latch is located on the surface of the outer casing and adapted so that it can be inserted into the LC socket, the flexible latch being one part with the activation element formed on the housing, designed to absorb pressure that disconnects the latch from the LC socket. The body further includes a shank enabling the outer outer surface of the housing to be inserted into its first

EP2 279 441 section and includes a mounting structure located on its second section and adapted to insert a protective sleeve. The optical fiber connector further includes a sleeve body positioned within its body and locked between the outer casing and a shaft, where the sleeve body includes a fiber tip located on the first section of the sleeve body. The fiber tip consists of the first optical fiber mounted in the ferrule and has a first end near the ferrule's end plane and a second end. The sleeve body further includes a mechanical welding assembly disposed in a second section of the body, the mechanical welding system being constructed to weld the other end of the fiber tip to the second optical fiber.

The above summary is not intended to describe each illustrated embodiment or every implementation of the present invention. The drawings and the detailed description show the examples of execution in a more detailed perspective.

Brief description of the drawings

The present invention will now be described with reference to the accompanying drawings, in which:

Fig. 1 is an isometric view of a fiber optic connector in accordance with an embodiment of the present invention.

Fig. 2 is an exploded view of an optical fiber connector in accordance with an embodiment of the present invention.

Fig. 3 is an isometric view of an example of the fiber optic connector of Fig. 2.

Fig. 4 is an isometric view of a duplex fiber optic connector in accordance with an embodiment of the present invention.

Fig. 5 is a top view of an exemplary optical fiber connector section in accordance with an embodiment of the present invention.

Fig. 6 is an isometric view of an exemplary sleeve body in accordance with an embodiment of the present invention.

Fig. 7 is an exploded view of the clamp section - lever protector sleeve 30 of an exemplary optical fiber connector in accordance with an embodiment of the present invention.

Figures 8 and 9 are isometric views of an alternative fiber optic connector not included in the claims.

EP2 279 441

Fig. 10 is an isometric view of an exemplary platform for terminating an optical fiber cable in a field installation in accordance with another embodiment of the present invention.

Fig. 11A is an exploded view of an optical fiber connector in accordance with yet another embodiment of the present invention.

Fig. 11B is an isometric view of the fiber optic connector of Fig.

11A.

Although the present invention can be implemented using various modifications and its alternative forms, its specific features, illustrated by means of examples in the drawings, will be described in detail below. Therefore, it should be understood that the description is not intended to limit the features of the invention to the specific embodiments described. On the contrary, the intention of the description is to include any modifications as well as equivalent and alternative solutions falling within the scope of the invention in accordance with the definitions of the appended claims. Detailed Description of Embodiments of the Invention In the detailed description of the invention below, reference is made to the accompanying drawings which form part thereof and illustrate specific examples of the practical embodiment of the invention. In this regard, for orientation in the described Figures, terminology such as "up", "down", "front", "back", "leading", "forward", "trailing" etc. was used. since the components present in the examples of the present invention can be oriented in different directions, this terminology has been used to illustrate the structure, so it cannot be used to introduce restrictions in any way. Therefore, it should be understood that other embodiments may exist, and structural or logical changes may also be made without departing from the scope of the present invention.

The present invention relates to an optical fiber connector. The fiber optic connector of embodiments of the invention is a compact, optical length LC connector that allows easy termination of the fiber optic cable in a field installation. The exemplary connector described here can easily be installed and used in home user type installations (FTTH) and / or in a broadband telecommunications system (FTTX). An example connector can be used

EP2 279 441 in environments requiring ease of use when working with a multitude of connections, especially in cases where labor costs are higher.

According to an exemplary embodiment of the present invention, the fiber optic connector 100 is shown in the isometric view in Fig. 1 and in the exploded view in Fig. 2. Figures 3-7 show other views of the connector 100 or its components. Fiber optic connector 100 has been designed to match the type of LC socket. The LC fiber optic connector 100 may include a body consisting of a body 110 and a fiber protective sleeve 180. In such an exemplary embodiment, the body 110 consists of an outer housing 112 with a frontal face adapted to be inserted into the LC socket (e.g. LC connector, LC adapter or LC socket), terminal 116 (also referred to as "shaft"), which provides further structural support and closes the end of the connector including ferrule 132, sleeve body 120, and connector spring 155.

The housing 112 has the shape of an external LC format. In addition, the body 110 includes a latch 115 located on the outer surface of the housing 112 and adapted to be inserted into the LC socket and secured the connector 100 in place. The latch 115 can be depressed and is flexible enough to allow the connector to be inserted / removed from the LC socket after activating the latch with a small amount of pressure. In addition, as shown in Fig. 3, the latch 115 is extended backwards (i.e. opposite to the face of the face 102). The latch 115 has a bottom section 114B of the rear edge adapted to contact the top surface 117 of the clamp 116 when the latch is depressed. This design provides a latch lock and prevents over-bending and excessive tension of the latch 115 due to repeated pressing during use.

The body 110 also includes an opening 113A on the side of the housing

112 sufficiently large to allow access to the mechanical welding assembly 140 contained therein (see further discussion below). In one aspect of the invention, in the housing 112, opposite to the opening 113A, there are one or more access slots 113B, allowing access to the mechanical welding assembly from the other side

The clamp 116 is shaped so that it can slip or snap onto the outer surface of the rear section of the housing 112. A portion of the flange formed on the inner surface of the clamp 116 (see Fig. 3) is the abutment plane for the spring based on the flange

EP2 279 441

155. The clamp or shank 116 may further include a solid mounting structure

118 located on the rear section of the clamp and enabling coupling to the clamping ring, fastening connector or protective sleeve 180, which can be used to protect the optical fiber against losses due to bending stress. As shown in Fig. 3, the fiber protective sleeve 180 is connected to the mounting structure 118 located on the rear section of the clamp 116. In an alternative aspect, for example when using a fiber optic cable in a sheath comprising one or more reinforcing threads, a clamping ring can be used to attach the reinforcing threads of the cable sheath to the terminal 116.

According to an exemplary embodiment of the present invention, a housing

112 and clamp 116 may be formed or cast from a polymer material, although metals and other suitably rigid materials may be used. In a preferred aspect of the invention, the outer casing 112 is formed of a more flexible or flexible material than the material of the clamp 116.

The connector 100 further includes a sleeve body 120 located and secured in the connector housing. According to exemplary embodiments, the sleeve body 120 (the sleeve body element may also appear under the name "barrel") is a multifunctional element in which the fiber tip assembly, mechanical welder 140 and fiber buffer clamp 126 are located. The sleeve body is designed so that it can move axially to a limited extent in the clamp 116. For example, the sleeve body 120 may include a shoulder or flange 125 (see Fig. 3) used as a spring seat 155 between the sleeve body and the clamp 116 when the fiber tip assembly is inserted into the socket. According to an exemplary embodiment of the present invention, the sleeve body 120 may be formed or cast from a polymer material, although metals and other suitable materials may be used. For example, the sleeve body 120 may be injection molded as an integral part. The sleeve body 120 is attached to the body 110 through the clamp section 116, as shown in the cross-sectional view in Fig. 3.

In particular, the sleeve body 120 includes a first end section

121 (see Fig. 6), in which there is a hole for inserting the fiber tip assembly including the ferrule 132 with the optical fiber 134 secured therein. As can be seen in Fig. 3, the sleeve body 120 also consists of a channel

EP2 279 441 fiber guide, guiding the fiber 184 towards the ferrule. The sleeve body 120 may further comprise an adapted or flattened section or sections 127 ensuring the correct alignment in the connector housing when the sleeve body is moved in the housing during operation. Correct angular alignment can also be beneficial when using ferrule polished fiber optic connector (APC). Alternatively, both the ferrule and the sleeve body may contain appropriately adapted shapes to maintain angular alignment.

To provide support for the inserted and protected optical fiber 134, ferrule 132 can be formed of ceramic, glass, plastic or metal. In a recommended aspect, ferrule 132 is made of ceramic material. Optical fiber 134 is introduced through ferrule 132 in such a way that the first fiber tip protrudes slightly, or is aligned or coplanar with the end surface of ferrule 132. Preferably, the end of the first fiber end should be factory polished (i.e., flat or at an angle, with or without a bevel). The other end of the fiber 134 protrudes partly from the interior of the connector 100 and is used to connect the second optical fiber, e.g., field installation optical fiber 184. Preferably, the other end of the optical fiber 134 can be cut (flat or at an angle, with or without beveling). In one aspect, the other end of the optical fiber 134 can be polished at the factory to reduce the sharp edges of the fiber, which can lead to cuttings (contamination) when installed in the welder. For example, an electric arc can be used to melt the fiber tip and form a rounded end, the same as that used in a conventional fiber optic welder. The electric arc technique can be used in conjunction with polishing using an abrasive to improve the shape of the end surface while reducing the possible deformation of the core. An alternative non-contact method uses laser energy to ablate / melt the fiber.

Fiber tips and field fibers include single-mode or multi-mode fibers such as SMF 28 (available from Corning Inc.). In an alternative embodiment, the fiber 134 additionally has a carbon coating on the outer surface of the fiber to provide further protection

EP2 279 441 glass based fibers. In an exemplary aspect, the fiber 134 is pre-installed and secured (e.g., using epoxy resin or other adhesive) in ferrule 132, which is located in the first end section 121 of the sleeve body 120. Ferrula 132 is preferably attached to sleeve body section 121 using epoxy resin or other suitable adhesive. Preferably, the pre-installation of the fiber tip should be done at the factory.

As shown in Fig. 6, the sleeve body 120 also includes a welding body section 123. In an exemplary aspect, the welder housing section 123 has an opening 122 in the central cavity of the sleeve body 120 to allow insertion and attachment of the mechanical welder 140. In the exemplary embodiment, the mechanical welder 140 includes a mechanical joining device (also referred to as a welding device or welder) similar to the construction of the 3M ™ FIBRLOK ™ mechanical fiber welding machine used, available from 3M Company, Saint Paul,

Minnesota. In this exemplary aspect, the mechanical welder 140, comprising welding element 142 and activation cap 144, is a smaller structure compared to a conventional device for mechanically connecting optical fibers due to the smaller proportions of the LC format (compared with e.g. the conventional SC connector format).

For example, the welding element 142 is formed of a plastic sheet of material and includes a hinge connecting two legs around the fiber axis, each of the legs having a channel for gripping the fiber (e.g. with a V-shaped wedge groove (or similar) ensuring optimization of conventional clamping forces glass fiber that is inside.

The plastic material can be, for example, aluminum or anodized aluminum. In one aspect, a conventional fluid with selected refractive index may be pre-introduced into the region of the V-groove V of the connecting element, providing an improvement in the optical connection within the connecting element. In another aspect of the invention, a conventional fluid with a selected refractive index is not used. For example, the element 142 used for the LC connector housing may have a length of about 7.62 to 10.16 mm (0.3 to 0.4 inches), preferably about 8.89 mm (0.350 inches), and a height of 2.54 to 5.08 mm (0.1 to 0.2 inches), preferably about 3.3 mm (0.13 inches) and width (when tightened) about 0.762 to 1.016 mm (0.03 to 0.04 inches), preferably 0.889 mm (0.035 inches).

EP2 279 441

Welding element 142 may be inserted into the mounting device or holder located in the body portion 123 of the sleeve 120. In an exemplary embodiment, the handle is integrally formed in the sleeve body 120, e.g., by injection molding. The cradle 124 can determine (e.g., tight fitting or snap-fit) the axial and transverse position of the mechanical welder 140. For example, one or more retainers 129 (see Fig. 6), such as offset hooks, can be used to secure the handle 142 in the appropriate axial position and / or the correct height before activating the attachment. In this way, the mechanical welder 140 cannot be rotated after installation, nor easily moved forward or backward.

In the exemplary embodiment, as the cap 144 moves from the open position to the closed position (i.e., in the direction of arrow 145 shown in Fig. 2), one or more guides located on the inner section of the cap 144 move to the protrusions of the connecting member, forcing the parts to move each other. Two fiber ends (e.g. one end of the fiber 134 and one end of the fiber 184) are held in place in the grooves formed in the connecting element and pushed in front of each other and joined together in a channel, ensuring a sufficient optical connection when approaching the protrusions of the element.

Similar but larger connecting elements are described in US Patent No. 5,159,653. In accordance with alternative aspects of the present invention, other conventional mechanical joining devices which are described in US Patent Nos. 4,824,197 may also be used; 5,102,212; 5,138,681 and 5,155,787.

A mechanical welder allows a field technician to connect the other side of the fiber tip 134 to 184 optical fiber at the field installation site. The expression "connecting" used here should not be understood in an exclusive sense, since the welding machine 140 also allows the removal of the optical fiber. For example, after prior activation, the element may be "re-opened" because the sleeve body may have slots allowing the insertion of a tool that moves the attachment 144 from the activated position in the handle to the open position. This configuration allows you to change the position of the connected fibers and then move the cap to the activated position

EP2 279 441

In addition, the sleeve body 120 includes a fiber buffer clamp section 126, enabling the fiber buffer section 184 in the field installation to be clamped during connection. In an exemplary aspect, the fiber buffer terminal section 126 is located inside the terminal 116 of the completely assembled joint. In a preferred aspect of the invention, the fiber buffer clamp section 126 is an integral part of the connector structure. For example, Fig. 6 shows one or more slots formed in the fiber buffer clamp segment 126, which creates a shape similar to a collet. This configuration causes the clamping fingers 128 to press and grip the fiber buffer section 184 of the field installation in a situation where the sleeve 160 slides on the buffer clamp 126, displacing the sleeve 160 axially towards the connector housing. Other alternative terminal designs, such as those described in US Publication No. 2007/0104425 A1, may also be used.

In an exemplary aspect, the connector 100 further includes a lever element 130. Lever element 130 is located between the protective sleeve 180 and the clamp 116. In one aspect, the lever element 130 has an opening to allow it to pass through the clamp section 118 (see Fig. 7). Lever element 130 includes a frontal plane section 133 with a recess for receiving a fitted hub 114 formed on the outer surface of the rear terminal section 116. Lever element 130 also includes a rear portion 139 of the rear face with a recess for receiving a front portion of the front face 181 formed on the outer surface of the protective sleeve 180. This design can reduce the effect of lateral loads applied to the sleeve.

Lever 130 further includes a forwardly projecting latch 135 (i.e., it extends toward the front face 102 of the body) that is adapted to engage the body latch 115 in a situation where the latch lever 135 is activated by applying a slight pressure. Due to the small size of the LC format connector and the corresponding socket, as well as due to the limited space requirements for devices with LC sockets, direct access to latch 115 to remove connector 115 may be difficult. Thus, the latch lever 135 provides the user with easy access to remove the LC connector. For example, as seen in Fig. 3, after pressing the latch lever 135, the section of the bottom surface of the latch 135 may touch the section 114A

EP2 279 441 upper surface of the lever 115 on the body. The upper surface of the latch lever 135 may have a protrusion or similar structure providing better grip to facilitate removal of the connector inserted into the socket.

The lever 130 may be formed of a material similar to the material of the shell 112, or a more flexible or flexible material such as nylon. In one example aspect, the lever material is more flexible than the coating material because it can withstand repeated pressure applied.

The lever 130 is also constructed in such a way that the connector 100 can be coupled to the second LC connector in an easy duplex format.

Conventional LC connectors often require an additional part (such as a handle) to form the duplex LC connector kit. In contrast, in the exemplary aspect shown in Fig. 5, the lever 130 includes an integrated coupling mechanism that provides coupling of the first LC connector to the second LC connector. Furthermore, in another alternative aspect, the plurality of connector sets are not limited to a duplex configuration only. For example, in the case of the above design, it is easy to couple to each other, depending on the application, more than two connectors (e.g. three, four, ten, etc. sets of connectors).

In this aspect, the coupling mechanism includes a dovetail protrusion 138 formed on the surface of the first side of the lever 130 and a corresponding slot 137 formed on the opposite surface of the lever 130, the slot 137 being designed to slide slidably and slackly with the dovetail portion of the second lever optical fiber connectors. For example, as shown in Fig. 4, the 100A / 100B duplex connector includes a first LC 135A coupled to a second LC 135B. Such a coupling mechanism can establish the correct separation distance between the connected duplex connectors. Other integrated coupling mechanisms may also be used, such as the ball-socket mechanism, or the tongue and groove mechanism. In addition, for convenience in the field, each of the terminals 116 is provided with identification labels 117 (see Fig. 7) situated on opposite external walls, such as "A" on one side and "B" on the other (or "1" and "2", etc., respectively).

In addition, the latch lever 135 includes a cap or surface 136 of the activation member that can easily be touched by a user's thumb or other finger to press on the latch. Moreover, as shown in Fig. 1,

The cap surface 136 may include a bottom edge section 136A (protruding from one end of the cap 136) and a top edge segment 136B (protruding from the other side of the cap 136. These projections are designed to guide the second lever cap when using the duplex format. For example, as shown in Fig. 4, a section of the underside of the lever 130A of the connector 100 is located immediately below the section of the protruding underside of the lever 130B of the connector 100B. Thus, the user may press the portion of the latch lever cap 135B and also cause the portion of the latch lever cap 135A to press the respective latch housings of both duplex connectors.

To prevent sharp bending of the fiber at the connector / fiber interface, a socket 180 is used. The socket 180 is coupled to the rear end of the connector 100. As mentioned above, the protective sleeve has a section 181 of the frontal plane formed on the outer surface of the sleeve 180 between the section 139 of the rear plane of the lever 130 and the rear section 118 of terminal 116 (see, e.g., Fig. 3). In an exemplary aspect, the sleeve 180 has a tail 182 with an extended shape, which ensures correct operation characteristics when using different types of fibers found as 184 fiber in a field installation (e.g., 250 pm or 900 pm fibers). This type of sleeve can be pre-installed at the factory (i.e., applied to the connector before the fiber ends in the field installation. Alternatively, a different shape of the protective sleeve can be used. Other sleeve configurations are described in US Publication No. 2007/0104425 A1.

In an alternative aspect, shown in Figures 8 and 9, the connector latch may have a one-piece configuration. For example, Fig. 8 shows a LC type connector 200 that includes a body 210 with an outer housing 212 made to be inserted into an LC format socket. The clamp 216, similar to the one described above, can be used as the support structure of the connector shaft 200. The lever 230 also provides assistance in better coupling of the sleeve 280 to the clamp 216. In such an alternative configuration, the latch 215 is made as a single adjacent latch that engages the outer body housing with the clamp. Such an alternative structure forms a continuous longitudinal member that bends or deflects in the central region of the joint. As shown in Fig. 9, in the pre-installed position 215B, the latch flattens when the terminal 230 is moved away from the front point of the connector. In the installed position 215A, the latch has raised

A surface 236 that is easily pressed by the user's finger. This alternative configuration ensures that the lever and latch remain in constant contact, which can reduce the potential for breakage.

In yet another alternative embodiment, the connector latch may have the one-piece configuration shown in Figures 11A and 11B. For example, Figures 11A and 11B show an LC type connector 300. Connector housing 310 includes an external housing 312 that fits into an LC format socket, and a terminal 316 that can serve as the structure of a stem support in the housing. The clamp or stem 316 may further include a robust mounting structure 318 located on the rear section of the clamp and allowing engagement with the clamp ring, fastener or protective sleeve 380, which can be used to protect the optical fiber against losses due to bending stress. The protective sleeve 380 is connected to the mounting structure 318 located on the rear section of the clamp 316.

In such an alternative embodiment, there is no separate lever component. In such an alternative configuration, the latch 315 is made as a single adjacent latch that is formed on the outer casing structure 312. In particular, the latch 315 is connected to the outer casing 312 both at the front end (near the top of the ferrule, as shown in Fig. 11B), as well as at the rear end (near terminal 316). The latch 315 further includes an activating element surface 336, preferably formed in the form of a large plate near the rear end of the outer casing 312, so it can be easily activated with the user's thumb or other finger to press the latch to slide the connector 300 out of the socket (e.g. from adapter / compression fitting - not shown). Clamp 316 has a cut-out 317 that allows the clamp 316 to be slid over the back of the outer casing 312 and provides space for the latch 315. The clamp 316 can be attached to the outer casing 312 via the latching mechanism 311A, 311B. Also in this alternative aspect, the terminal 316 may include a coupling mechanism for connecting the connector 300 to the second connector in a duplex or other multi-connector format. In a preferred aspect, the coupling mechanism includes a dovetail protrusion formed on the surface of the first side of the clamp 316 (not shown) and matched to

EP2 279 441 a cutout 337 made on the surface of the opposite side of the clamp 316.

Cutout 337 is made so as to provide a sliding and matched insertion of the dovetail section of the next adjacent joint.

In addition, for convenience when servicing the field installation, the 316 clamp is equipped with identification labels located on opposite external walls, such as "A" on one side and "B" on the other (or "1" and "2", etc. .).

The connector 300 further includes a sleeve body 320 located and secured in the connector body. According to exemplary embodiments, the sleeve body 320 is a multifunctional element that includes a fiber tip assembly, a mechanical welder 340, and a fiber buffer clamp 326. The sleeve body 320 may be designed the same or similar to the sleeve body 120 described in detail above. In addition, the sleeve body 320 may be molded or injection molded from a polymer material, although metals and other suitable materials may be used as described above. The sleeve body 320 is secured in the housing 310 using the clamping section 316, as described above. The sleeve body 320 also houses a spring 355 that attaches to a flange portion formed on the inner surface of the clamp 316.

The sleeve body 320 further houses a mechanical welder 340, same or constructed similar to the welder 140 described above. In the exemplary embodiment, the welding machine 340 is a mechanical welding device comprising a connecting element 342 and an activation cap 344, designed to be smaller than a conventional device for mechanically connecting optical fibers due to the smaller proportions of the LC format (compared with e.g. a conventional connector format) SC).

In particular, the sleeve body 320 includes a first end section in which an opening is provided to allow insertion of a fiber tip assembly including ferrule 332 with fiber 334 attached therein. To provide support for the inserted and protected fiber 334, ferrule 332 may be formed of ceramic material , glass, plastic or metal, in the same or similar way to ferrule 132 described above. The other end of the optical fiber 334 protrudes partly from the interior of the connector 300 and is used to connect the second optical fiber, for example optical fiber 384 of the field installation (see Fig. 11B). This alternative configuration reduces

EP2 279 441 the likelihood that the latch is inadvertently broken and provides a more accessible design of the latch activating element.

In another exemplary aspect, a fiber optic cable termination procedure and a cable termination platform in an field installation are provided. The fiber optic cable termination procedure and the field installation platform for cable termination are described with reference to Fig. 10. In this exemplary embodiment, the LC connector body is attached to the 400 platform for field installation, enabling the technician to perform many stages of fiber optic cable termination on one integrated device. An example platform for field installation can be equipped with one or more fiber guide sections, allowing easy and reliable line alignment and insertion of the fiber into the connector. Fiber optic guides can also ensure the correct positioning of the very small fiber tip without the need for optical devices or good lighting.

Alternative constructions of platforms for field installations similar to those described in US publication no. 2007/0104425 A1 may also be used.

Particularly, the field installation platform or tool 400 ensures repeatable, accurate fiber insertion into the fiber optic connector and introduces the correct upset length / voltage force regardless of the type of fiber. In addition, the field installation platform discussed in the context of this embodiment of the invention allows the installer to use a completely assembled connector during fiber optic cable terminating operations. The field installation platform discussed in this alternative embodiment of the invention can be cheaply manufactured, enabling the customer to use an inexpensive tool.

Platform 400 includes a base section 410 with a guide channel

412, retracting finger 413 and lock release lever 411. The platform 400 further includes a connector handle or holder 402 constructed so that during the fiber optic cable termination procedure, an LC fiber connector such as LC type connector 100 can be inserted and secured. As shown in Fig. 10, the connector 100 is positioned sideways to allow sufficient access to the mechanical welding mechanism.

The connector holder 402 can be attached to the platform using a mechanical connector, such as screws or latches. Alternatively, the connector holder 402 may be glued to the platform or attached with any other

EP2 279 441 by welding, e.g. welded. The connector holder 402 may advantageously be attached to the base section 410 using a removable connector, which allows the connector holder to be replaced when handling a different format connector.

The platform 400 may further include an activation mechanism 440 that includes an activation cap or an activation plate 446 designed to touch and press on the attachment of the joint welding mechanism, for example the attachment 144 of the mechanical welder 140. For example, the activation attachment or plate 446 pressure can be exerted to move this element toward the attachment until it is touched and the mechanical welding machine is activated. In such an exemplary embodiment, the activation plate 446 can be connected to the base 410 via brackets 444. In addition, the brackets 444 can be constructed to be attached to the base 410.

Additionally, platform 400 is equipped with a fiber handle assembly 470 including a base 472 of the fiber handle assembly. In a preferred embodiment, the base 472 of the fiber grip assembly is configured so that it can be slidably inserted into the channel 412 of the platform base 410. In addition, the base 472 of the fiber handle assembly has its channel or formed cutout 471. According to an exemplary aspect of the invention, the platform base 410, fiber handle assembly 470, and components thereof may be formed or injection molded from a polymer material.

The fiber grip assembly 470 includes a buffer clamp actuator and fiber grip components 492A, 492B and 492C. The fiber holder components are designed to support and temporarily attach the optical fiber during the optical fiber termination procedure. Each of the fiber holder sections may include one or more aligned fiber guides or channels, which provides better linear support for the fiber along a significant length of platform. For example, the fiber guides or channel 491 are shown on the rear section of the fiber holder assembly.

In such an exemplary embodiment, the first fiber grip 492A is formed as part of the buffer clamp activation member, so it is a subassembly of assembly 470 slidably inserted into the notch or channel 471. The buffer clamp activation member may include a funnel shaped fiber guide (or funnel) 482 , used for both driving

EP2 279 441 fiber as well as activating the buffer terminal mechanism of the connector 100 secured in the holder 402.

The fiber grip base assembly 472 includes a second fiber grip section 492B and a third fiber grip section or clamp 492C pivotally attached to the fiber grip base assembly 472. In addition, the fiber holders 492A, B and C may use the same or different clamping mechanisms. For example, the fiber holder 492A may be snap-locked onto the fiber after insertion, but the handle cover may be movable, allowing insertion of fibers of various diameters. The fiber holder 492B can be closed on the fiber after insertion, but is preferably not latched, so the fiber is held by gravity. To securely attach the fiber to the handle assembly, the fiber handle section 492C may be adapted to snap close onto the p-fiber to insert it.

The base 410 further includes locks 420 designed to block the sliding movement of the buffer clamp activation member forward, e.g., upon contact with the buffer clamp holders or blocks 486A and 486B. The locks 420 may still protrude slightly above channel 412, which helps to prevent base 472 from lifting from channel 412 during bending of the fiber.

The fiber holder base assembly 472 may further include locks that are intended to be inserted into the locks formed in the base 410 and, optionally, inserted and combined in a conventional fiber knife. In this way, the fiber can be guided in the same tool before and after the end of the fiber optic cable.

The buffer clamp activation element is designed to activate or activate the buffer clamp sleeve, i.e. the buffer clamp sleeve 160 (see, e.g., Fig. 2). For example, the buffer clamp activation member may include a funnel-shaped fiber guide 482 with a tip section designed to contact the sleeve 160 or section. The funnel-shaped section provides for guiding the fiber, e.g. the 135 optical fiber, which is introduced into the tool. The buffer clamp activating element may also include handles or blocks 486A and 486B that allow user accessible contact points for moving the buffer clamp activating element during termination of the fiber optic cable.

EP2 279 441

Each section of the fiber holder may have at least one fiber guide that guides them when terminating the fiber optic cable.

For example, the fiber holder 492C may be formed in the form of an eccentric clamp used when moved to the closed position to hold the fiber in the guide during termination of the optical fiber cable. In addition, the fiber holder 492C may include a piece of foam or other compliant material attached to its underside so that it will form to the clamped fiber. In addition, a rear fiber channel 491 may be provided at the end of the base assembly 472 to provide further support. With this design, fibers of varying stiffness can easily be caught and guided on the 400 platform.

As mentioned above, in such an alternative embodiment, the platform 400 includes a base section 410 with an indexing finger 413 and a lock release lever 411 formed thereon. The retracting finger 413 may be formed in the form of a projection in such a way that the base 472 of the fiber grip assembly can be slidably inserted into the channel 412, whereby the finger 413 may join or press on the side of the base 472 of the fiber grip assembly to temporarily hold the base 472 of the assembly of the fiber holder in place, preventing the axial displacement of the base assembly 472 as the terminated fiber begins to bend.

Lock release lever 411 may also be formed in base 410, providing closure in such a way that the connector buffer clamp, e.g., sleeve 160, is not prematurely activated by the buffer clamp activation member 480. For example, at the end of its path, the buffer clamp actuator subassembly cannot move further without activating the lock release lever 411. In this exemplary embodiment, the lock release lever 411 may be designed as a pushing mechanism with the arm 414 that engages with one of the handles or blocks 486A and 486B until the pushing mechanism is released by the user, which displaces the arm 414 to disengage it from the buffer clamp or block.

In practice, the 400 platform can easily be used in the procedure of terminating the fiber optic cable in the field installation for a LC 100 connector. In addition, the technician may use a fiber optic connector

EP2 279 441 completely assembled at the factory, so the use of an additional connector assembly is not necessary for field work.

For example, the connector 100 may be installed in the coupling connector

LC or holder 402, e.g. by snap-in insertion. In this example, the connector 100 may be used with the sleeve 180 pre-fitted on the optical fiber connector. After the connector is mounted, the welder activation mechanism 440 can return to a position just above the welding cap 144.

Optical fiber, e.g. 184 optical fiber, can be prepared by removing the sheath and cutting (straight or angled) to match the orientation of the pre-installed fiber tip. Optical fiber 184 can be prepared before entering into assembly 470, or after entering into assembly 470. In one aspect for preparing the fiber tip, its length can be extended to a suitable dimension, e.g., 40 mm to 50 mm beyond the end of the fiber handle assembly. The buffer clamp activation member may be moved away from the handle 470 along the cutout or channel 471 to a sufficient distance to provide fiber support during removal of the sheath and trimming. The plastic coating / fiber sheath can be removed using a conventional mechanical stripping tool. The small length of the plastic coating may protrude beyond the end of the 470 assembly. A section of the glass fiber surface may be wiped clean. Trimming using a mechanical cutter such as described above can be carried out when the fiber is secured in place in the fiber clamp assembly.

Before activation, the buffer clamp activation member 480 may be located on the front side of the fiber handle assembly 470. The terminated optical fiber, e.g. 184 optical fiber, may be installed in the fiber holder assembly after the fiber has been laid in the funnel-like segment 482 of the buffer clamp activating element and on top of the fiber guides. Optical fiber 184 can be attached by introducing fiber holder sections 492A, B and C, and moving one or more fiber holder sections to a closed position. The fiber holder sections can be designed to clamp the outer sheath of a standard optical fiber, e.g., a conventional optical fiber with a 900 pm buffer coating or a 250 pm buffer coating.

The fiber can then be pulled back along the fiber holder assembly so that the prepared fiber end is aligned with

EP2 279 441 with the tip of the funnel 482. This arrangement can protect the fiber tip during this stage of the fiber termination procedure. In addition, this setting allows the fiber tip to be pre-inserted into the rear end of the connector without the need for visual inspection of the fiber tip location, since the tip of the buffer clamp actuator is used for such control.

The fiber handle assembly 470, along with the held, prepared fiber, can be inserted into channel 412 of the base 410 of the platform. The fiber handle assembly can be moved forward (i.e. toward the assembled connector) after applying a small force to the base 472 of the handle assembly.

The base 472 and the buffer clamp activation member are moved along the channel 412 until the lock release lever 411, e.g., arm 414, is actuated by at least one of the handles or blocks 486A and 486B. Such actuation of the buffer clamp activating member locks stops the top of the funnel until the locking release lever 411 is moved by the user, as discussed above. The fiber assembly 472 can be further advanced in the channel 412.

As the assembly 472 continues to move forward, as the prepared fiber tip begins to touch the protruding fiber end 134 in the connector housing welder, the first fiber holder segment 492A may be actuated by blocks in the base assembly 472. As the blocks move relative to the stationary subassembly of the buffer clamp, the first block begins to lift the fiber holder segment 492A. During the further axial movement of the base 472, the second block begins to raise the fiber holder section 492A even more.

The gradual, automatic pickup of fiber holder section 492A allows bending or arcing up of fiber 184 when the prepared tip contacts the protruding fiber after stopping the axial displacement of the fiber. In addition, the cover of the second section 492B of the fiber holder can also be designed to rise to allow bending of the fiber occurring when using fibers of a certain stiffness. In addition, in the event that the fiber end contacts the fiber tip, an indexing finger 413 may prevent the base 472 from moving away from the connector holder.

EP2 279 441

To activate the mechanical welder in connector 100, you can then press the activation cap or activation element 446, pressing it against the welding cap in the connector, e.g. cap 144.

To release the arm 414, connected to at least one of the five handles or blocks 486A and 486B, you can then press the lock release button 411, allowing the clamp activation member 480, and especially the apex section, to be moved further forward in connector direction. The top of the funnel can be pushed completely forward to activate the connector buffer sleeve 160 of the connector 100.

After activating the buffer terminal, the connector is terminated. The fiber clamp 492C can be moved back to the open position, releasing fiber swelling, and the LC type connector 100 can be removed from the LC 402 coupling.

Thus, as can be understood from the above description, the platform of the alternative embodiment can work with a wider range of fibers and their stiffness, e.g. with fibers in 250 pm coatings, 900 pm soft PVC coatings, 900 pm rigid nylon coatings, etc. the platform ensures that the permissible axial force applied to the fiber tip is maintained. Such force should be large enough for the fiber to be introduced into the welding area in the joint, but not excessive so as not to damage the tip of the fiber. This tool allows for proper fiber introduction and easy removal of the complex LC connector.

Optionally, the coupling housing or connector 402 may be further constructed so that it can be coupled to the detector or light source to test the quality of the terminated LC connector. In addition, during termination, the user can position the detector system with a light source to monitor signal loss. The activating element can be lifted and the terminated connector removed from the holder or coupling 402. The connector can then be used by the user as required.

Thus, in accordance with such an alternative embodiment, complete instrumentation or platform can be used to implement the fiber termination of the LC connector in the field installation without the need for polishing the fiber in the field or using epoxy resins. In addition, the tool or platform can be used many times. With this configuration in

EP2 279 441 of this platform can easily be caught and guided fibers with even a high degree of bending (resulting from winding the fiber on the spool). The joint can therefore be pre-assembled at the factory, even with the pre-assembled sleeve. The buffer clamp activation mechanism can be used to protect the fiber also during its initial insertion into the LC connector.

The LC connector described above can be used in many conventional fiber optic connector applications. The fiber optic connectors described above can also be used to terminate (apply connectors) optical fibers for direct direct connection and patching of fiber optic networks inside distribution points in the equipment room or wall terminal strips, inside connection racks, junction boxes or cabinets, or internal sockets in rooms used for fiber optic cable applications. The fiber optic connectors discussed above can also be used for terminating optical fibers in optical equipment. In addition, one or more of the fiber optic connectors discussed above can be used in alternative applications.

As mentioned above, the LC connector of embodiments of the invention has a compact length and is capable of being easily terminated in a field installation allowing a reduction in assembly time. Such exemplary connectors can easily be installed and used in FTTP and / or FTTX network installations, such as fiber optic distribution units.

The design of the LC connector enables further compact configurations in other outdoor applications, such as connection racks, cabinets, terminals and, among others, in fiber optic network intrusion detection (NIDS) systems.

Various modifications, equivalent procedures, and numerous designs in which the present invention may be used will be immediately apparent to those skilled in the art who have read the specification and will be interested in the present invention.

EP2 279 441