Optical waveguides – Accessories
Reexamination Certificate
2000-03-22
2004-11-09
Nguyen, Khiem (Department: 2839)
Optical waveguides
Accessories
C385S059000
Reexamination Certificate
active
06816661
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to the connectorization of optical fibers and, more particularly, to multifiber connectors, installation tools and associated methods for validating optical fiber continuity during the connectorization process.
BACKGROUND OF THE INVENTION
Although fiber optic connectors can generally be most efficiently and reliably mounted upon the end portions of optical fibers in a factory setting during the production of fiber optic cable, many fiber optic connectors must be mounted upon the end portions of optical fibers in the field. As such, a number of fiber optic connectors have been specifically developed to facilitate field installation. One advantageous type of fiber optic connector that is specifically designed to facilitate field installation is the UNICAM® family of fiber optic connectors provided by Siecor Corporation of Hickory, N.C. While the UNICAM family of fiber optic connectors includes a number of common features including a common splicing technique, the UNICAM family of fiber optic connectors has several different styles of connectors including UNICAM connectors adapted to be mounted upon a single optic fiber and UNICAM connectors adapted to be mounted upon two or more optical fibers, such as the MT-RJ UNICAM connector. See, for example, U.S. patent application Ser. No. 09/108,451 filed Jul. 1, 1998 and assigned to Siecor Corporation, which describes a multifiber connector, such as an MT-RJ UNICAM connector, adapted to be spliced onto the end portions of a plurality of optical fibers. The contents of this patent application are hereby incorporated by reference in their entirety.
By way of example of an advantageous fiber optic connector designed for field installation,
FIG. 1
depicts an MT-RJ UNICAM® connector
10
. The connector generally includes a ferrule
12
defining one or more bores for receiving respective optical fiber stubs. The optical fiber stubs are preferably sized such that one end of the optic fiber stubs extends rearwardly beyond the ferrule. The MT-RJ UNICAM® connector also includes splice components, at least one of which defines a groove for receiving an end portion of each optical field fiber upon which the fiber optic connector is to be mounted. In order to mount the fiber optic connector upon optical field fibers, the splice components are positioned proximate the rear end of the ferrule, such that the end portions of the optical fibers stubs that extend rearwardly beyond the ferrule are disposed within the respective grooves defined by the splice components. Thereafter, end portions of the optical field fibers can also be inserted into the respective grooves defined by the splice components. By inserting the optical field fibers into the grooves defined by the splice components until respective end portions of the optical fiber stubs and the optical field fibers make contact, optical connections can be established between respective pairs of the optical fiber stubs and the optical field fibers. In this regard, the contact between the end portions of the optical fiber stubs and the optical field fibers establishes optical continuity between respective pairs of the optical fiber stubs and the optical field fibers. The splice components can then be actuated, such as by means of a cam member
20
, in order to force the splice components together and to secure the end portions of the optical fiber stubs and the optical field fiber in position within the respective grooves defined by the splice components.
In order to facilitate the connectorization of optical fibers in the field, installation tools have also been developed. For example, U.S. Pat. No. 5,040,867 to Michael de Jong et al. and U.S. Pat. No. 5,261,020 to Michael de Jong et al. describe installation tools for facilitating the connectorization of optical fibers in the field. In addition, a UNICAM® installation tool kit is provided by Siecor Corporation of Hickory, N.C., to facilitate the mounting of the UNICAM® family of connectors upon the end portions of optical field fibers in the field. An installation tool holds a number of components of the fiber optic connector including the ferrule and the splice components while the optical field fibers are inserted into the fiber optic connector and aligned with the respective optical fiber stubs.
In this regard, one conventional installation tool includes a base and a tool housing mounted upon the base. The installation tool also includes an adapter disposed within the tool housing. The adapter has a first end for engaging the fiber optic connector that is to be mounted upon the optical field fibers and an opposed second end that is a dust cap. The installation tool also includes a bias member mounted within the tool housing that engages a shoulder defined between the first and second ends of the adapter in order to secure the adapter in position within the tool housing. Typically, the bias member includes a slide member slidably connected to the tool housing and a biasing element, such as a spring, for urging the slide member into engagement with the shoulder defined by the adapter. The slide member generally includes an engagement portion having a U-shape through which the second end of the adapter extends. In addition, a conventional slide member includes a base portion disposed between the tool housing and the base and connected to the engagement portion by means of a connecting element that extends through a lengthwise extending slot defined by the tool housing. Thus, the movement of the connecting element through the slot defined by the tool housing guides the corresponding movement of the slide member in a lengthwise direction relative to the tool housing in order to engage the shoulder defined by the adapter, thereby securing the adapter in position within the tool housing.
In order to mount the fiber optic connector upon the end portions of the optical field fibers, the fiber optic connector is mounted within the installation tool. In particular, the forward end of the fiber optic connector is engaged by the first end of the adapter which, in turn, is secured within the tool housing once the slide member is biased into engagement with the shoulder defined by the adapter. The end portions of the optical field fibers are then inserted into the rear end of the fiber optic connector and the splice components are subsequently actuated, such as by being cammed together, in order to secure the optical field fibers relative to respective optical fiber stubs. The crimp tube
24
of the fiber optic connector is then crimped about the optical field fibers and, in some applications, a crimp band
26
is crimped to the strength members surrounding the optical field fibers in order to provide strain relief and otherwise protect the splice connections of the optical field fibers and the optical fiber stubs.
Once fiber optic connectors have been mounted upon the opposed end portions of the optical field fibers, the resulting fiber optic cable assembly is preferably tested end-to-end. Among other things, this testing is designed to insure that optical continuity has been established between the optical fiber stubs and respective optical field fibers. While fiber optic cables can be tested in different manners, one test involves the introduction of light having a predetermined intensity into each optical fiber stub. By measuring the light following its propagation through the fiber optic cable assembly and, more particularly, by measuring the insertion loss and back reflectance onto each optical fiber stub with a power meter, the continuity of each optical field fiber and the respective optical fiber stub can be determined. If the testing indicates that the optical fibers are not sufficiently continuous, the technician must either scrap the entire fiber optic cable assembly or, more commonly, replace one or both fiber optic connectors in an attempt to establish the desired continuity. In order to replace the fiber optic connectors, a technician generally removes, i.e., cuts off, one of the
Barnes Brandon A.
Church Thomas A.
de Jong Michael
Giebel Markus A.
Kerr Sean M.
Corning Cable Systems LLC
Nguyen Khiem
LandOfFree
Multifiber connector, installation tool and associated... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Multifiber connector, installation tool and associated..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Multifiber connector, installation tool and associated... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3350433