Description:
FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10, Rule 13]

“PRE-TERMINATED OPTICAL FIBER CABLE ASSEMBLY FOR INSTALLATION THROUGH A DUCT”

STERLITE TECHNOLOGIES LIMITED, an Indian Company at:15th & 16th Floor, Capital Cyberscape, Sector 59, Gurugram, Haryana - 122102

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.

FIELD OF THE INVENTION:
[01] The invention relates to a pre-terminated optical fiber cable assembly configured to be installed through a duct.

BACKGROUND OF THE INVENTION:
[02] Various optical fiber cables, including pre-terminated assemblies, have been designed to reduce installation errors and speed up the process. A first type of pre-terminated optical fiber cable assembly uses LC or SC connectors. However, LC connectors (minimum width 7 mm) and SC connectors (minimum width 9 mm) cannot be installed in ducts narrower than their respective sizes such as a 6 mm duct.

[03] U.S. Patent No. 11,966,088 proposes a second type of assembly with a terminator at the cable’s end, allowing installation in ducts narrower than 7 mm or 9 mm. After installation, the terminator is connected to an outer housing resembling LC (7 mm) or SC (9 mm) connectors. The terminator includes a ferrule, ferrule holder, ferrule housing, inner housing, and a spring, all designed to ensure axial movement, prevent rotation, and reduce signal degradation when under load. However, even the second type of assembly has its challenges. In particular, the second type of assembly has a complex design, involving multiple parts. Thus, manufacturing of the second type of assembly is complicated and due to which the manufacturing cost increases. Also, aligning components like the ferrule, ferrule holder, ferrule housing, and inner housing is difficult, as is fitting the terminator into the outer housing. The spring can cause parts to disassemble under stress.

[04] Therefore, a need exists for a simpler, more efficient pre-terminated optical fiber cable assembly to address these issues.

SUMMARY OF THE INVENTION:
[05] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key or essential features.

[06] Accordingly, the present invention provides a pre-terminated optical fiber cable assembly for deployment through a duct tube, comprising:an optical fiber cable comprising one or more optical fibers; a ferrule assembly receiving at least one of the one or more fibers, the ferrule assembly comprising a ferrule coupled to a ferrule holder; a connector body coupled to the ferrule assembly such that rotation of the ferrule assembly with respect to the connector body is restricted; anda compressible element positioned inside the connector body, the compressible element exerting a biasing force on the ferrule assembly, such that ferrule assembly exhibits a relative axial movement of less than 0.3 mm and more than 0.0 mm with respect to the connector body.

[07] In an embodiment of the invention, the compressible element does not prevent rotation of the ferrule assembly with respect to the connector body.

[08] In an embodiment of the invention, the connector body comprises a stopper feature configured to prevent at least a part of the ferrule assembly from exiting through a front end of the connector body.

[09] In another embodiment of the invention, the ferrule assembly comprises a first physical feature and the connector body comprises a first mating physical feature, the first physical feature being adapted to engage with the first mating physical feature.

[010] In yet another embodiment of the invention, the first physical feature is provided at a region where a diameter of the ferrule holder is maximum or near maximum.

[011] In still another embodiment of the invention, the pre-terminated optical fiber cable assembly further comprises a cap configured to be removably mounted on the connector body such that the cap covers the ferrule assembly bulging out of the connector body during deployment, where the cap is configured to be removed after deployment and prior to engaging with an end connector housing.

[012] In a further embodiment of the invention, the connector body is configured to engage with end connector housing of an optical fiber connector after deployment through the duct tube thereby forming a connectorized cable assembly.

[013] In a furthermore embodiment of the invention, the pre-terminated optical fiber cable assembly is defined by a maximum radial dimension of D1, the connectorized cable assembly is defined by a maximum radial dimension of D2, and the duct tube is defined by an inner radial dimension (D3), where D2 > D3 > D1.

[014] In an embodiment of the invention, the connector body comprises a second physical feature configured to engage with a second mating physical feature provided in the end connector housing of the optical fiber connector, the second physical feature after engaging with the second mating physical feature restricting rotation rotational movement of the connector body and with respect to the end connector housing of the optical fiber connector.

[015] In another embodiment of the invention, the connector body comprises a third physical feature configured to engage with a third mating physical feature provided in the end connector housing of the optical fiber connector, the third mating physical feature guiding the third physical feature during insertion of the pre-terminated optical fiber cable assembly in a first orientation inside the end connector housing of the optical fiber connector.

[016] The invention further provides a method of assembling a pre-terminated optical fiber cable assembly, said method comprising:terminating one or more optical fibers of an optical fiber cable in a ferrule assembly of the pre-terminated optical fiber cable assembly; locating a compressible element inside a connector body; coupling the ferrule assembly to the connector body of the pre-terminated optical fiber cable assembly such that:(a) the compressible element is sandwiched between the ferrule assembly and the connector body; (b) rotation of the ferrule assembly with respect to the connector body is restricted; (c) at least a part of the ferrule assembly is bulging out of the connector body; and (d) the compressible element exerts a biasing force on the ferrule assembly limiting a relative axial movement between the ferrule assembly and the connector body to up to 0.3 mm, while not preventing rotation of the ferrule assembly with respect to the connector body. The method further comprises mounting a cap on the connector body such that the cap covers the ferrule assembly bulging out of the connector body.

[017] The invention furthermore provides a method of installing a connectorized cable assembly within a duct tube, said method comprising:pulling or pushing a pre-terminated optical fiber cable assembly having a maximum radial dimension of D1 through a duct tube of an inner radial dimension (D3); removing a cap of the pre-terminated optical fiber cable assembly; and engaging the pre-terminated optical fiber cable assembly with an end connector housing of an optical fiber connector, thereby installing the connectorized cable assembly defined by a maximum radial dimension of D2 within the duct tube, wherein D2 > D3 > D1. In the current invention, a smaller duct with a diameter up to 6mm is being used to pass an optical fiber cable with a diameter up to 5mm. The connector housing having a larger diameter up to 7mm is installed after passing the optical fiber cable through the duct. The optical fiber cable can also be passed through a linear duct as well as an angled duct by optical fiber cable pulling method or the like.

[018] To further clarify the advantages and features of the invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES:
[019] In order that the invention may be readily understood and put into practical effect, reference will now be made to exemplary embodiments as illustrated with reference to the accompanying drawings, where like reference numerals refer to identical or functionally similar elements throughout the separate views. The figures together with a detailed description below, are incorporated in and form part of the specification, and serve to further illustrate the embodiments and explain various principles and advantages, in accordance with the present invention where:

[020] Figure 1illustrates an exploded view of thepre-terminated optical fiber cable assemblyand a connectorized cable assembly in accordance with an embodiment of the invention;

[021] Figure 2illustratesa fully assembled view of the pre-terminated optical fiber cable assembly in accordance with an embodiment of the invention;

[022] Figure 3 illustratesa view of the pre-terminated optical fiber cable assembly after removal of the cap in accordance with an embodiment of the invention;

[023] Figure 4illustratesa side view of the pre-terminated optical fiber cable assembly which has been inserted into an inner housing of an optical fiber connector and an outer housing of the optical fiber connectorin accordance with an embodiment of the invention;

[024] Figure 5illustrates a top view of the connectorized cable assemblycomprising the pre-terminated optical fiber cable assembly which has been inserted into an inner housing of the optical fiber connector and an outer housing of the optical fiber connector in accordance with an embodiment of the invention;

[025] Figure 6 illustrates a close-up view of the inner housing of the optical fiber connector coupled to a combination of the connector body and the ferrule assembly in accordance with an embodiment of the invention;

[026] Figure 7 illustrates a first close-up view of the connectorized cable assemblydevoid of the optical fiber cable in accordance with an embodiment of the invention;

[027] Figure 8 illustrates a second close-up view of the connectorized cable assemblydevoid of the optical fiber cable in accordance with an embodiment of the invention;

[028] Figure 9 illustrates a close-up view of the connector body coupled to the ferrule assembly showing a sectional plane D-D in accordance with an embodiment of the invention;

[029] Figure 10 illustrates a sectional view of the connector body coupled to the ferrule assembly along the sectional plane D-D in accordance with an embodiment of the invention;

[030] Figure 11 illustrates a sectional view of the connector body along the sectional plane D-D in accordance with an embodiment of the invention;

[031] Figure 12 illustrates a close-up view of the ferrule assembly in accordance with an embodiment of the invention;

[032] Figure 13 illustrates a close-up view of the connector body coupled to the ferrule assembly showing a sectional plane E-E in accordance with an embodiment of the invention;

[033] Figure 14 illustrates a sectional view of the connector body coupled to the ferrule assembly along the sectional plane E-E in accordance with an embodiment of the invention;

[034] Figure 15 illustrates a sectional view of the connector body along the sectional plane E-E in accordance with an embodiment of the invention;

[035] Figure 16 illustrates a perspective view of the inner housing of the optical fiber connector in accordance with an embodiment of the invention;

[036] Figure 17 illustrates a rear view of the inner housing of the optical fiber connector coupled to a combination of the connector body and the ferrule assembly in accordance with an embodiment of the invention;

[037] Figure 18 illustrates a flow chart of a process of making the pre-terminated optical fiber cable assembly in accordance with an embodiment of the invention; and

[038] Figure 19 illustrates a schematic chart of assembling the connectorized cable assembly within a duct tubein accordance with an embodiment of the invention.

[039] It may be noted that to the extent possible, like reference numerals have been used to represent like elements in the drawings. Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the dimensions of some of the elements in the drawings may be exaggerated relative to other elements to help improve understanding of aspects of the present invention. Furthermore, one or more elements may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION OF THE INVENTION:
[040] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

[041] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the invention and are not intended to be restrictive thereof.

[042] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.

[043] Reference throughout this specification to “an aspect”, “another aspect” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrase “in an embodiment”, “in another embodiment”, and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.

[044] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that one or more devices or sub-systems or elements or structures or components proceeded by "comprises... a" does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

[045] As used herein, and unless the context dictates otherwise, the terms "coupled to", “connected to”, “operably connected to”, and “operatively connected to” are intended to include both direct connection / coupling (in which two elements that are coupled / connected to each other contact each other) and indirect coupling / connection (in which at least one additional element is located between the two elements). Therefore, the terms "coupled to" and "coupled with" are used synonymously. Similarly, the terms “connected to” and “connected with” are used synonymously.

[046] In the following paragraphs, one or more of the following technical terms may have been used, which are intended to have the following meaning:

[047] Optical fiber - The term “optical fiber” as used herein refers to a light guide that provides high-speed data transmission. The optical fiber has one or more glass core regions and one or more glass cladding regions. The light moving through the glass core regions of the optical fiber relies upon the principle of total internal reflection, where the glass core regions have a higher refractive index (n1) than the refractive index (n2) of the glass cladding region of the optical fiber. A non-glass material coating is provided over the optical fiber to protect the same from dust, dirt, debris and other environmental factors.

[048] Optical fiber cable - The term “optical fiber cable” as used herein refers to a cable that encloses one or more optical fibers along with one or more strength members. The optical fiber cable can have a diameter of up to 5mm for passing through a narrow duct tube for installation.

[049] Ferrule – The term “Ferrule” as used herein refers to a cylindrical bore made of ceramic material which can receive an optical fiber post removal of non-glass coating material.

[050] Ferrule holder - The term “Ferrule holder” as used herein refers to a metallic component to grab a rear end of the ferrule and to hold the ferrule at a desired place due to predefined shape of the ferrule holder.

[051] Connector: A connector is a type of fiber optic connector specifically designed to provide robust, reliable connections in environments that are subject to harsh conditions. These conditions can include extreme temperatures, moisture, dust, mechanical stress, and other environmental factors that would typically degrade the performance of standard fiber optic connectors. The connector comes in the following forms including local connector(LC type connector)and subscriber connector (SC type connector).

[052] The term “pre-terminated optical fiber cable assembly” as used in the specification means an optical fiber cable assembly not having a connector attached thereto.

[053] The term “connectorized cable assembly” as used in the specification means an optical fiber cable assembly not having a connector attached thereto.

[054] All technical and scientific terms used herein have the same meaning as commonly understood by one ordinary skilled in the art to which this invention belongs. The device, methods, and examples provided herein are illustrative only and not intended to be limiting.

[055] The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as being essential to the practice of the invention.

[056] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

[057] Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

[058] While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[059] The figures and the forgoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment. For example, orders of processes described herein may be changed and are not limited to the manner described herein. The scope of embodiments is by no means limited by these specific examples.

[060] Now referring to Figure 1and Figure 5, there is illustrated an exploded view and an assembled view of a connectorized cable assembly(150) in accordance with an embodiment of the invention. The connectorized cable assembly(150) comprises a pre-terminated optical fiber cable assembly(100) and an optical fiber connector (158), which may be an LC type connector or an SC type connector or any other type of connector. The optical fiber connector (158) may comprise an end connector housing (152). By way of a non-limiting example, the optical fiber connector (158) may comprise an inner housing (1521) and an outer housing (1522) which may be attached to one another. Referring to Figure 4,Figure 5, Figure 6, Figure 7, and Figure 8, if the optical fiber connector (158) comprises inner housing (1521) and outer housing (1522), the pre-terminated optical fiber cable assembly (100) is first connected to the inner housing (1521) and then the outer housing (1522) is placed so to surround the inner housing (1521) and connected to the inner housing (1521).

[061] Now referring to Figure 1, Figure 2 which illustrates an assembled view of the pre-terminated optical fiber cable assembly (100), and Figure 3 which illustrates the pre-terminated optical fiber cable assembly (100) after removal of a cap, in an embodiment of the invention, the pre-terminated optical fiber cable assembly (100) comprises an optical fiber cable (102) comprising one or more optical fibers (104); a ferrule assembly (106) receiving at least one of the one or more fibers (104);a connector body (112) coupled to the ferrule assembly (106); anda compressible element (114) positioned inside the connector body (112). The compressible element (114) exerts a biasing force on the ferrule assembly (106) and causes the ferrule assembly (106) to bulge out of a front end (118) of the connector body (112).

[062] The connector body (112) is coupled to the ferrule assembly (106) such that rotation of the ferrule assembly (106) with respect to the connector body (112) is restricted. The compressible element (114) allows relative axial movement between the ferrule assembly (106) and the connector body (112). At the same time, the compressible element (114) restricts relative axial movement between the ferrule assembly (106) and the connector body (112) to a value less than 0.3 mm and greater than 0.0 mm.Going beyond the mentioned value of the relative axial movement may create instability of the ferrule assembly (106) inside the connector body (112) and hence, may lead to instable connection. Thecompressible element (114) however does not restrict rotation of the ferrule assembly (106) with respect to the connector body (112). The compressible element (114) is used to provide a limited shock absorbent capacity to the ferrule assembly (106).In general, a metallic spring is used as a compressible element (114). Alternatively, a polymer such as but not limited to rubber or silicone-based element can be used as the compressible element (114).
[063] The ferrule holder (110) is made of a material such as but not limited to copper and the ferrule (108) is made of a material such as but not limited to zirconium. Thermal expansion coefficient of the ferrule holder (110) material and the ferrule (108) material is different such that a ratio of coefficient of thermal expansion of the ferrule holder (110) and coefficient of thermal expansion of the ferrule (108) is between 0.3 to 0.6.The ferrule (108) and ferrule holder (110) work in different jurisdictions with high temperature as well as low temperature. Hence, the material selection is done based on durability, high mechanical strength and other survival properties of the material. The required ration is also important in terms of optical connectivity properties such as but not limited to low insertion loss, low back reflection, thermal stability, chemical resistance, high melting points etc.

[064] The pre-terminated optical fiber cable assembly (100) further comprises a cap (126) configured to be removably mounted on the connector body (112) such that the cap (1262) covers the ferrule assembly (106) bulging out of the front end of the connector body (112). The cap (126) protects the ferrule (108) from dust, dirt, debris and other environmental factors.The pre-terminated optical fiber cable assembly (100) further comprises a hollow cylindrical member (132) locatable within the connector body (112). The hollow cylindrical member (132) surrounds the optical fiber cable (102) and provides strength to the optical fiber cable (102). The hollow cylindrical member (132) may be made of a plastic material selected from a group comprising
Polytetrafluoroethylene, Polyether Ether Ketone, Polyetherimide, Polyphenylene Sulfide, Polyvinylidene Fluoride, Polyamide, Ethylene Tetrafluoroethylene, and Polycarbonate.

[065] The pre-terminated optical fiber cable assembly (100) further comprises a crimp ring (134) attachable to a rear end of the connector body (112). The crimp ring (134) securely holds the optical fiber cable (102) with respect to the connector body (112). The pre-terminated optical fiber cable assembly (100) further comprises a heat shrink tube (136) surrounding the connector body (112).

[066] Now referring to Figure 1, the connector body (112) is coupled to the ferrule assembly (106) and Figure 12illustrates a close-up view of the ferrule assembly (106), in an embodiment of the invention. The ferrule assembly (106) comprises a ferrule (108) coupled to a ferrule holder (110). The ferrule assembly (106) further comprises a first physical feature (120) provided on an outer periphery thereof and the connector body (112) comprises a first matching physical feature (122). The first physical feature (120)is adapted to engage with the first mating physical feature (122)and prevents the ferrule assembly (106) from exhibiting rotation with respect to the connector body (112).

[067] By way of a non-limiting example, the first physical feature (120) may be in the form of a notch and the first mating physical feature (122) may be in the form of a slot. By way of another non-limiting example, the first physical feature (120) may be in the form of a slot and the first mating physical feature (122) may be in the form of a notch. By way of yet another non-limiting example, the first physical feature (120) may be in the form of a protrusion and the first mating physical feature (122) may be in the form of a channel. By way of still another non-limiting example, the first physical feature (120) may be in the form of a channel and the first mating physical feature (122) may be in the form of a protrusion. By way of still another non-limiting example, the first physical feature (120) and the first mating physical feature (122) can be a threaded mechanism, a twist-to-lock mechanism, interlocking grooves, adhesive bond or any other mechanical interlocking feature.The first physical feature (120) and first mating physical feature (122) prevents the rotation of optical fiber ferrule assembly (106) inside the connector body (112) to avoid breakage of an optical fiber (104) inside the connector body (112) due to any accidental twisting. Thecompressible element (114) doesn’t restrict rotation of the ferrule assembly (106) with respect to the connector body (112) because of an interlocking between the ferrule assembly (106) and the connector body (112) by the first physical feature (120) and the first mating physical feature (122).

[068] In an embodiment of the invention, the first physical feature (120) is provided at a region (124) where diameter of the ferrule holder (110) is maximum or near maximum. The region (124) also acts as a coupling region of the ferrule (108) and the ferrule holder (110). In some aspect, interlocking the maximum or near maximum region (124) of the ferrule assembly (106) with the connector body (112) provides a firm engagement between the ferrule assembly (106) and the connector body (112).

[069] Now referring to Figure 11 which is a sectional view of the connector body (112) taken along section D-D as shown in Figure 9, referring to Figure 10 which is a sectional view of the connector body (112) coupled to the ferrule assembly (106) taken along the sectional plane D-D shown in Figure 9,referring toFigure 15 which is a sectional view of the connector body (112) taken along section E-E as shown in Figure 13, and referring to Figure 14 which is a sectional view of the connector body (112) coupled to the ferrule assembly (106) taken along the sectional plane E-E shown in Figure 13, it can be seen that the front end (118) of the connector body (112) comprises a stopper feature (116) configured to prevent at least a part of the ferrule assembly (106) from exiting through the front end (118) of the connector body (112). The stopper feature (116) in the form of an inward protrusion of the front end (118) of the connector body (112). The inward protrusion is created at the front end (118) of the connector body (112) by a pressing tool after inserting the ferrule assembly (106) inside the connector body (112).The stopper feature (116) locks the maximum or near maximum region (124) of the ferrule assembly (106) inside the connector body (112) and hence, prevents the ferrule assembly (106) to come out from the connector body (112) due to biasing force applied by thecompressible element (114).

[070] In an embodiment of the invention, the connector body (112) comprises a first channel (138) extending along an axis of the connector body (112) and a second channel (140) extending along the axis of the connector body (112). The first channel (138) extends from an intermediate portion and towards a rear end (142) of the connector body (112). The second channel (140) extends from the intermediate portion and towards the front end (118) of the connector body (112). The first channel (138) has a first internal diameter (D4) and the second channel (140) has a second diameter (D5), the second diameter (D5) is greater than the first diameter (D4). The first channel (138) receives the hollow cylindrical member (132) and the optical fiber (104). The second channel (140) receives the compressible element (114).

[071] Now referring to Figure 9 to Figure 12, the ferrule holder (110) comprises a front end (144), a rear end (146) and a stepped structure (148) positioned between the front end (144) and the rear end (146). The rear end (146) of the ferrule holder (110) is sized to be inserted into the first channel (138). The front end (144) of the ferrule holder (110) is sized to protrude out of the front end (118) of the connector body (112). The stepped structure (148) has a front portion (160) and a rear portion (162). The front portion (160) of the stepped structure (148) is sized to come in contact with the stopper feature (116) provided on the front end (118) of the connector body (112) and hence, preventsthe ferrule holder (110) from exiting completely through the front end (118) of the connector body (112). The rear portion (162) of the stepped structure (148) comes in abutting relation with the compressible element (114) and due to which the compressible element (114) exerts the biasing force on the ferrule assembly (106). While in Figure 9toFigure 12 the stepped structure (148) is shown as a multi-step structure, it may be noted that the stepped structure (148) may be in the form of a single-step structure. By providing the stepped structure (148) in the ferrule holder (110), which is positioned between the front end (144) of the ferrule holder (110) and the rear end (146) of the ferrule holder (110), it becomes convenient to ensure that the ferrule assembly (106) in generally and the ferrule holder (110) in particular is prevented from exiting through the front end (118) of the connector body (112). Additionally, it becomes convenient to securely hold the compressible element (114) within the second channel (140) resulting in the compressible element (114) exerting the biasing force on the ferrule assembly (106).

[072] The ferrule (108) has a diameter which is smaller than a diameter of the ferrule holder (110) and hence, only the ferrule holder (110) comes in contact with the stopper feature (116) provided on the front end (118) of the connector body (112)and no portion of the ferrule (108) comes in contact with the stopper feature (116).This ensures that the ferrule (108) is clear and free of scratches even if the ferrule assembly (106) exhibits relative axial movement with respect to the connector body (112). It may also be noted that the notch (120) is provided in the ferrule holder (110) especially at the stepped structure (148). This ensures that the notch (120) is at the highest elevation on the ferrule assembly (106) and hence can be easily positioned in the first slot (122) of the connector body (112),and that the ferrule (108) is clear and free of scratches even if the ferrule assembly (106) exhibits relative axial movement with respect to the connector body (112).

[073] In an embodiment of the invention, the connector body (112) comprises a threaded portion (164) for removably receiving the cap (126). In an embodiment of the invention, the threaded portion (164) is positioned behind the first slot (122). By positioning the threaded portion (164) behind the first slot (122), attachment or removal of the cap (126) to the connector body (112) does not affect the notch (120) which is positioned within the first slot (122). In some aspect, the connector body (112) and the cap (126) can be engaged together by an adhesive bond or a mechanical locking mechanism.

[074] In addition to restricting rotational movement between the ferrule assembly (106) and the connector body (112), there generally arises a need to align the combination of the ferrule assembly (106) and the connector body (112) with respect to the inner housing (1521) of the optical fiber connector (158). To enable the above, the connector body (112) comprises a second physical feature (128) is configured to engage with a second mating physical feature (154) provided in the end connector housing (152), the second physical feature (128) after engaging with the second mating physical feature (154) restricts rotational movement of the connector body (112) with respect to the end connector housing (152). Referring to Figure 6, it can be seen that the first housing (1521) comprises the second mating physical feature (154), the combination of the ferrule assembly (106) and the connector body (112) inserted into the first housing (1521) and the second physical feature (128) being engaged with the second mating physical feature (154).

[075] By way of a non-limiting example, the second physical feature (128) may be in the form of a bulge portion and the second mating physical feature (154) may be in the form of a channel. By way of another non-limiting example, the second physical feature (128) may be in the form of a channel and the second mating physical feature (154) may be in the form of a bulge portion.

[076] Now referring particularly to Figure 15, the connector body (112) further comprises a third physical feature (130). The third physical feature (130) is positioned diametrically opposite to the first matching physical feature (122) on the connector body (112). Now referring to Figure 17, in an embodiment of the invention, the third physical feature (130) is configured to engage with a third matching physical feature (156) provided in the end connector housing (152) of the optical fiber connector (158). In particular, the third matching physical feature (156) is guided by the third physical feature (130) during insertion of the pre-terminated optical fiber cable assembly (100) inside the enc connector housing (152) of the optical fiber connector (158).

[077] By way of a non-limiting example, the third physical feature (130) may be in the form of a bulge portion or a protrusion and the third mating physical feature (156) may be in the form of a slot or a channel. By way of another non-limiting example, the third physical feature (128) may be in the form of a slot or a channel and the third mating physical feature (156) may be in the form of a bulge portion or a protrusion.

[078] Now referring to Figure 18, the present invention further provides a method (200) of making the pre-terminated optical fiber cable assembly (100). The method (200) comprises passing (202) an optical fiber cable (102) comprising one or more optical fibers (104) through a connector body (112). The method (200) further comprises locating (204) a compressible element (114) inside the connector body (112). The method (200) further comprises terminating (206) the one or more optical fibers (104) of the optical fiber cable (102) in a ferrule assembly (106). The method (200) further comprises coupling (208) the ferrule assembly (106) to the connector body (112) such thatthe compressible element (114) is sandwiched between the ferrule assembly (106) and the connector body (112); rotation of the ferrule assembly (106) with respect to the connector body (112) is restricted; at least a part of the ferrule assembly (106) is bulging out of the connector body (112); and the compressible (114) exerts a biasing force on the ferrule assembly (106) limiting a relative axial movement between the ferrule assembly (106) and the connector body (112) up to 0.3 mm, while not preventing rotation of the ferrule assembly (106) with respect to the connector body (112). The method (200) further comprises mounting (210) a cap (126) on the connector body (112) such that the cap (126) covers the ferrule assembly (106) bulging out of the connector body (112) to obtain the pre-terminated optical fiber cable assembly (100).

[079] Now referring particularly to Figure 19, the invention further provides a method (300) of installing a connectorized cable assembly (150) within a duct tube (50). The method comprises pulling or pushing (302) a pre-terminated optical fiber cable assembly (100) having a maximum radial dimension of D1 through the duct tube (50) of an inner radial dimension (D3); removing (304) a cap (126) of the pre-terminated optical fiber cable assembly (100); and engaging (306) with one or more housing (152) with the pre-terminated optical fiber cable assembly (100), thereby installing the connectorized cable assembly (150) defined by a maximum radial dimension of D2 within the duct tube (50), wherein D2 > D3 > D1.

[080] Now referring to Figure 4, Figure 6, Figure 16, Figure 17 and Figure 19, it can be observed that the connector body (112) is configured to engage with one or more housing (152) after deployment through the duct tube (50) thereby forming a connectorized cable assembly (150). In an embodiment of the invention, the pre-terminated optical fiber cable assembly (100)is defined by a maximum radial dimension of D1, where the connectorized cable assembly (150) is defined by a maximum radial dimension of D2, and the duct tube (50) is defined by an inner radial dimension (D3), where D2 > D3 > D1.

[081] One of the advantages of the connectorized cable assembly (150) can be installed in ducts having diameter less than 7 mm.

[082] Another advantage of the invention is that the pre-terminated optical fiber cable assembly (100) is substantially simple in terms of its construction as it comprises very few parts. The essential parts are merely three i.e. the ferrule assembly (106), the connector body (112), and the compressible element (114). Even if take into account the optional elements such as the hollow cylindrical member (132), the crimp (134), and the heat sink tube (136), the total number of parts is still very less. In some instances, the hollow cylindrical member (132) and the connector body (112) can be formed together as a single part, thus further reducing the total number of parts.

[083] This leads to substantial ease in making of the pre-terminated optical fiber cable assembly (100). Because of lesser number of parts and the ease of making the pre-terminated optical fiber cable assembly (100), cost of the pre-terminated optical fiber cable assembly (100) as well cost of the connectorized cable assembly (150) are substantially low.

[084] The pre-terminated optical fiber cable assembly (100) comprises simple construction in terms of the first physical feature (120) and the first matching physical feature (122), which ensures that the ferrule assembly (106) is properly aligned with respect to the connector body (112). Also, it takes very less amount of time to properly align the ferrule assembly (106) with respect to the connector body (112). Also, the first physical feature (120) and the first matching physical feature (122) further function to restrict rotation of the ferrule assembly (106) with respect to the connector body (112).

[085] By providing the stopper feature (116) at the front end (118) of the connector body (112), it becomes to simply to ensure that the at least a part of the ferrule assembly (106) does not exit through a front end (118) of the connector body (112). Also, the stepped structure (148) provided on the ferrule holder (110) is a simple construction which ensure that the at least a part of the ferrule assembly (106) does not exit through a front end (118) of the connector body (112).

[086] The pre-terminated optical fiber cable assembly (100) comprises simple construction in terms of the second physical feature (128) and the third physical feature (130) both of which contribute to properly aligning the pre-terminated optical fiber cable assembly (100) within the inner housing (1521) and restricting rotational movement of the pre-terminated optical fiber cable assembly (100) with respect to the inner housing (1521).

[087] Additionally, the compressible element (114) is held safely between the ferrule holder (110) and the second channel (140) and hence, the process of making the pre-terminated optical fiber cable assembly (100) is simplified.

[088] Traditional pre-terminated optical fiber cable assemblies often encounter challenges during deployment through duct tubes, particularly when the connector size is too large to fit through the duct. A practical solution is required to enable the attachment of the SC connector only after the cable has passed through the duct. Additionally, twisting or misalignment between the ferrule assembly and the connector body during installation can lead to reliability issues. The present invention addresses these shortcomings.

[089] The SC connector designed in this invention is attached after the cable has been deployed through the duct, allowing for seamless installation without being hindered by the connector's larger diameter. This approach resolves the issue of oversized connectors obstructing deployment through ducts with smaller diameters.

[090] A no-twist mechanism has been incorporated, ensuring that the ferrule assembly and connector body remain securely aligned and do not twist relative to one another. This design enhances the reliability of optical connections post-installation.

[091] The no-twist mechanism is implemented in a straightforward and cost-effective way, comprising:
a. A notch on the ferrule assembly that interlocks with matching slots on the connector body.
b. A compression spring that enables axial movement while preventing unwanted rotation of the ferrule assembly. This spring allows for minor adjustments during installation, ensuring proper alignment between the ferrule assembly and the connector body while maintaining stability.
c. An alignment tab on the connector body designed to guide and align the SC connector during attachment. This feature simplifies installation, ensures accurate alignment, and enhances overall reliability.

[092] The scope of the invention is defined by the claims, and it should be understood that the invention includes all modifications, variations, or equivalents that fall within the scope of the claims.While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein.

[093] The invention contributes to solving a specific problem; however, it may not be the only factor in the solution. Other variables may influence the outcome, and such factors will be recognized by a person ordinarily skilled in the art. While the invention provides a solution to the described problem, its effectiveness may be influenced by various external factors, which are recognized by persons ordinarily skilled in the art.The invention may be practiced as a method or apparatus, and the specific mode of implementation may vary while still falling within the scope of the claims.
, Claims:WE CLAIM:

1. A pre-terminated optical fiber cable assembly (100) for deployment through a duct tube (50),comprising:
an optical fiber cable (102) comprising one or more optical fibers (104);
a ferrule assembly (106) receiving at least one of the one or more fibers (104),the ferrule assembly (106) comprising a ferrule (108) coupled to a ferrule holder (110);
a connector body (112) coupled to the ferrule assembly (106) such that rotation of the ferrule assembly (106) with respect to the connector body (112) is restricted; and
a compressible element (114) positioned withinthe connector body (112), the compressible element (114)exerting a biasing force on the ferrule assembly (106), such that ferrule assembly (106) exhibits a relative axial movement of less than 0.3 mm and more than 0 mm with respect to the connector body (112).

2. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the ferrule holder (110) is formed of a material with a different coefficient of thermal expansion than the ferrule (108) such that a ratio of coefficient of thermal expansion of the ferrule holder (110) and coefficient of thermal expansion of the ferrule (108) is between 0.3 to 0.6.

3. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the compressible element (114) plays no role in rotation of the ferrule assembly (106) with respect to the connector body (112).

4. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the connector body (112) comprises a stopper feature (116) integral to the connector body (112) configured to prevent at least a part of the ferrule assembly (106) from exiting through a front end (118) of the connector body (112).

5. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the ferrule assembly (106) comprises a first physical feature (120) that is adapted to engage with the first mating physical feature (122) of the connector body (112).

6. The pre-terminated optical fiber cable assembly (100) as claimed in claim 3, wherein the first physical feature (120) being provided at a region where diameter of the ferrule holder (110) is maximum or near maximum.

7. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, comprising a cap (126)configured to be removably mounted on the connector body (112) such that the cap (112) is configured to cover an end of the ferrule assembly (106) bulging out of the connector body (112) during deployment, wherein the cap (126) is configured to be removed after deployment and prior to engaging with an end connector housing (152).

8. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the connector body (112) is configured to engage with an end connector housing (152) after deployment through the duct tube (50) thereby forming a connectorized cable assembly (150), where the pre-terminated optical fiber cable assembly (100) is defined by a maximum radial dimension of D1, where the connectorized cable assembly (150) is defined by a maximum radial dimension of D2, and the duct tube (50) is defined by an inner radial dimension (D3), where D2 > D3 > D1.

9. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the connector body (112) comprises a second physical feature (128) configured to engage with a second mating physical feature (154) provided in the end connector housing (152), the second physical feature (128) after engaging with the second mating physical feature (154) restricting rotational movement of the connector body (112) with respect to the end connector housing (152).

10. The pre-terminated optical fiber cable assembly (100) as claimed in claim 1, wherein the connector body (112) comprises a third physical feature (130) configured to engage with a third mating physical feature (156) provided in the end connector housing (152), the third mating physical feature (156) being guided by the third mating feature (130) during insertion of the pre-terminated optical fiber cable assembly (100) inside the end connector housing (150).
11. A method (200) of making a pre-terminated optical fiber cable assembly (100), said method comprising:
a. passing (202) an optical fiber cable (102) comprising one or more optical fibers (104) through a connector body (112);
b. locating (204) a compressible element (114) inside the connector body (112);
c. terminating (206) the one or more optical fibers (104) of the optical fiber cable (102) in a ferrule assembly (106);
d. coupling (208) the ferrule assembly (106) to the connector body (112)such that:
i. the compressible element (114) is sandwiched between the ferrule assembly (106) and the connector body (112);
ii. rotation of the ferrule assembly (106) with respect to the connector body (112) is restricted,
iii. at least a part of the ferrule assembly (106) is bulging out of the connector body (112); and
iv. the compressible element (114) exerts a biasing force on the ferrule assembly (106) limiting a relative axial movement between the ferrule assembly (106) and the connector body (112) to upto 0.3 mm, while not preventing rotation of the ferrule assembly (106) with respect to the connector body (112); and
e. mounting (210) a cap (126) on the connector body (112) such that the cap (126) covers the ferrule assembly (106) bulging out of the connector body (112) to obtain the pre-terminated optical fiber cable assembly (100).

12. A method (300) of installing a connectorized cable assembly (150) within a duct tube (50), said method comprising:
pulling or pushing (302) a pre-terminated optical fiber cable assembly (100) having a maximum radial dimension of D1 through the duct tube (50) of an inner radial dimension (D3);
removing (304) a cap (126) of the pre-terminated optical fiber cable assembly (100); and
engaging (306) the pre-terminated optical fiber cable assembly (100)with an end connector housing (152) engaged with an end connector, thereby installing the connectorized cable assembly (150)defined by a maximum radial dimension of D2within the duct tube (50), wherein D2 > D3 > D1.