Cross-Reference to Related Applications

This application claims the benefit of U.S. Patent Application Serial No. 62/978,237, filed on February 18, 2020, and claims the benefit of U.S. Patent Application Serial No. 63/046,530, filed on June 30, 2020, the disclosures of which are incorporated herein by reference in their entireties.

Background

Fiber optic cables carry optical fibers used to transmit optical signals between providers and subscribers. Typically, large cables, such as trunk cables or “main” cables, carry a large number of fibers. The fibers of the main cable are spliced, split, optically connected to other fibers (e.g., via fiber optic connectors), or otherwise managed and routed to a desired destination, (e.g., a subscriber building). Due to the large number of fibers that need to be managed and routed, the main cable is often terminated in a fiber optic splice closure. Such fiber optic splice closures typically include an outer ruggedized and sealable shell defining an interior volume and one or more sealable ports for sealed cable entry to the interior. The closures can be adapted for outdoor or indoor use. The interior volume of a splice closure typically houses structures and equipment, such as splice trays to organize and route fibers to facilitate both storing of fibers and routing of fibers to their desired destinations. In the case of tubes which receive fiber optic cables such as blown optical fibers, there is a need to seal against the inner surface of the tube and the fiber optic cable to prevent gas or water from passing through the tube and into a telecommunications closure.

Summary A blocking device and method is provided for transitioning between two tubes. The blocking device includes an inner tube positioned within a first tube extending toward a closure, a first housing and a sealing gel. The device further includes a second housing for connection to a second tube and a moveable sleeve, such as a threaded nut, which connects the first and second housings together, and moves the first and second housings together.

The inner tube is moveable from within the blocking device to an area away from the device to allow for the gel to seal around the fiber and an interior of the device. The inner tube can function as a fiber protector inside of the closure for fiber routing.

A blocking device and method is useful where there is a need to seal an interior of a tube relative to a fiber optic cable. One environment is for blown fiber tubing, after the fiber is placed in the tubing.

The blocking device and method is also useful if the fiber is placed in the tubing such as by pulling or pushing the fiber through the tubing.

Brief Description of the Drawings

FIG. 1 shows a blocking device connecting first and second tubes together outside of a closure, wherein a dome of the closure has been removed for clarity, so that interior features of the closure can be seen including a tube fixation location and a fiber protective tube holder;

FIG. 2 shows the closure of FIG. 1 including a protective inner tube extending from the first tube within the closure;

FIG. 3 shows an exploded view of the first tube, the protective inner tube, a first housing, and sealing gel separated from the first housing;

FIG. 4 shows the first tube connected to the first housing, and the inner tube positioned within the first housing wherein the inner tube passes through the gel;

FIG. 5 shows the assembly of FIG. 4, including a heat shrink tube between the first tube and the first housing;

FIG. 6 shows the second tube, a second housing, and a threaded nut prior to assembly;

FIG. 7 shows the second tube mounted to the second housing;

FIG. 8 shows a situation where a fiber has already been blown or otherwise placed through the second tube prior to assembly of the second tube to the second housing; FIG. 9 shows the nut positioned over the second housing;

FIG. 10 shows the first and second housings of the assemblies of FIGS. 4 and 9, with the nut beginning to threadably engage with the first housing;

FIG. 11 shows the assembly of FIG. 10 wherein a fiber is blown or otherwise placed through the first and second tubes;

FIG. 12 shows the direction of movement of the inner tube away from the gel, and movement of the threaded nut to move the first and second housings toward one another, thereby allowing the gel to seal around the fiber;

FIG. 13 are further views of the blocking device of FIGS. 1-12, wherein the second housing, the second tube and the nut are separated from the first housing including the first tube and the inner tube, with the inner gel;

FIG. 14 shows the nut drawing the second housing toward the first housing to allow for fiber blowing or passage of the fiber between the two tubes;

FIG. 15 shows the activated gel wherein the nut has drawn the first housing toward the second housing and the inner tube has been withdrawn to allow the gel to seal around the optical fiber;

FIG. 16 is an isometric view of the various parts shown in FIGS. 13-15;

FIG. 17 is an exploded view of the parts shown in FIG. 16;

FIG. 18 is an isometric view of the second housing;

FIG. 19 is another isometric view of the second housing;

FIG. 20 is a cross-sectional view showing portions of the second tube separated from the second housing and the nut in a first position relative to the second housing;

FIG. 21 shows the second tube mounted to the second housing and the nut in a secured position pressing inwardly on the arms of the second housing relative to the view of FIG. 20;

FIG. 22 shows an alternative embodiment of a blocking device in perspective view;

FIG. 23 shows the blocking device of FIG. 22 in exploded view;

FIG. 24 shows an enlarged view of the blocking device of FIG. 22; FIG. 25 shows an another enlarged view of the blocking device of FIG.

22;

FIG. 26 shows the blocking device of FIG. 22 in cross-sectional side view, before the gel blocking tube is moved;

FIG. 27 shows the blocking device of FIG. 22 in cross-sectional side view, after the gel blocking tube is moved.

Detailed Description

A blocking device 10 allows for the blocking of a blown fiber tube after the fiber optic cable is positioned in the tube for placement in a closure 70, of the type shown in FIGS 1 and 2. In the case of device 10, a seal against gas or water is created within the tubing and a fiber optic cable.

The blocking device 10 transitions between two tubes 20, 22. The blocking device 10 includes an inner tube 30 positioned within a first tube 20 extending toward a closure 70, a first housing 32 and a sealing gel 34. The device 10 further includes a second housing 50 for connection to a second tube 22 and a moveable sleeve 52, such as a threaded nut 52, which connects the first and second housings 32, 50 together, and moves the first and second housings together.

The inner tube 30 is moveable from within the blocking device 10 to an area away from the device to allow for the gel 34 to seal around the fiber and an interior of the device. The inner tube 30 can function as a fiber protector inside of the closure for fiber routing.

Closure 70 includes a seal block 72, a cable/tube fixation area 74, a tube holder area 76, and an organizer 78 with cable routing and fiber tray 80. As shown in FIG. 2, the inner tube 30 extends past the end 82 of first tube 20. Inner tube 30 can function as a fiber protector inside of the closure for fiber routing.

The blocking device and method is useful where there is a need to seal an interior of a tube relative to a fiber optic cable such as to protect the interior of closure 70 from water or gas. One environment in particular is for blown fiber tubing, after the fiber is placed in the tubing. The blocking device and method is also useful if the fiber is placed in the tubing such as by pulling or pushing the fiber through the tubing.

Device 10 includes an incoming tube 22 and an outgoing tube 22. Contained within tubes 20 and 22 is an optical fiber. Once device 10 is activated, a seal is provided so that any liquid or gas in tube 22 is not passed through tube 20 through an interior of the tubes. Device 10 can be located outside of the closure, so that space in the closure is not restricted or has to be expanded.

Referring to FIGS. 3-5, device 10 includes a first housing or a base interface 32 and gel 34 received in cavity 36. Internal threads 40 at first end 24 receive an end 26 of first tube 20. Inner tube 30 is slidably received in first tube 20. Initially an end 44 of tube 30 is positioned in cavity 36 and is surrounded by gel 34. A heat shrink 46 may be provided to further secure base interface 32 with tube 22. The components of FIGS. 3-5 can be factory assembled, if desired.

Referring now to FIGS. 6-9, an interface tube or second housing 50 and a nut 52 connect tube 22 to base interface 32. Cavity 36 of base interface 32 includes an inner anti rotation surface 42 that mates with an external anti-rotation surface 54 of interface tube 50 at second end 33 of interface tube 50. Interface tube 50 also includes a flange 56 and a second end 58 with internal threads 60. Nut 52 is positioned over tube 22 and tube 22 is threadably inserted into interface tube 50.

FIG. 8 show a situation where the fiber is already present in the tube 22, and then device 10 can be assembled around fiber 90 for sealing.

Referring to FIGS. 10-12, the nut 52 is then threadably mounted to threads 48 on second end 28 of base interface 32. Once the fiber 90 is located inside of tubes 20, 30, and 22, tube 30 can be withdrawn and nut 52 can be tightened drawing interface tube 50 toward gel 34 so as to seal both ends of the internal chamber of device 10 around the optical fiber.

Base interface 32 can have a non-circular exterior 64, and nut 52 can have a non-circular exterior 66. A hex shape can allow for easy gripping or the use of tools for tightening of the parts.

FIGS. 13-15 show various views of the device 10 during assembly (FIGS. 13 and 14), and after sealing (FIG. 15). FIGS. 16 and 17 show in perspective view the various parts of device 10.

FIGS. 18-21 show interface tube 50 provided with fingers 65 and slots 67 at end 31 wherein the inner passage can accommodate different tube sizes. Nut 52 includes a chamfer and bottom edge 68 to slide over the fingers 65 and press them inwardly against tube 22. Thinned area 84 helps promote inward bending of fingers 65.

FIGS. 22-27 show an alternative blocking device 110. Instead of inner tube 30 being placed to shield the fiber 90 from the gel 34, a second, separate inner tube 130 is provided. Inner tube 30 becomes a first inner tube 30 and is positioned away from the gel, yet still within first tube 20. Inner tube 30 can still be used as a protective tube for the fiber from device 110 to the closure.

Second inner tube 130 is positioned within the blocking device 110 to shield fiber 90 from gel 34. After fiber 90 is placed in second inner tube 130, second inner tube 130 is pulled away from device 110 to allow gel 34 to surround fiber 90 and seal the interior of device 110 around fiber 90 as first housing 132, second housing 150 and movable sleeve 152 are drawn together by threads 48, 60.

Second inner tube 130 can either be pushed up further into second tube 22 out of the way, or removed entirely from its position around fiber 90 by passing fiber 90 through a lengthwise slit in second inner tube 130. Second tube 22 is attached to second housing 150. Then nut 152 is reattached to base interface 32, and then tightened to seal device 110. Fingers 165 tighten around tube 22. Exterior surfaces 164, 166 define non-circular shapes (e.g., hex) and can be engaged by tools to tighten device 110.

Ribs 174 on first housing provide a gripping surface for added adhesion of a heat shrink 46.

An anti-rotation device 180 can be provided to help prevent sleeve 152 from untightening from first housing 132. One example is a device which includes a flexible tab 182 with a shoulder and a ramp 184.

As seen in FIGS. 22-27, fingers 165 are more fully enclosed by sleeve 152, than device 10, to reduce bending of the tips of fingers 165.

The above specification, examples and data provide a complete description of the manufacture and use of the composition of the invention. Since many embodiments of the invention can be made without departing from the spirit and scope of the invention, the invention resides in the claims hereinafter appended.