Abstract:
A fitting for routing cables between first and second ducts in a raceway system, the first duct having a first cross-sectional dimension and the second duct having a second and different cross-sectional dimension from the first cross-sectional dimension, the fitting including a first end for attaching to the first duct, a second end for attaching to the second duct, and an insertable reducer disposable generally between the first and second ends of the fitting, the reducer for adapting the fitting to transition between the first and second cross-sectional dimensions, the reducer including a barb for bitingly engaging at least one of the ducts and retaining the at least one duct to said fitting.

Description:
RELATED APPLICATION  
         [0001]    Applicant claims, under 35 U.S.C. §119(e), the benefit of priority of the filing date of Oct. 31, 2001, of U.S. Provisional Patent Application Serial No. 60/335,011, filed on the aforementioned date, the entire contents of which are incorporated herein by reference.  
         FIELD OF THE INVENTION  
         [0002]    The present invention relates to the field of duct-type cable routing systems. More specifically, the invention relates to a reducer used to attach duct of a relatively smaller size to duct of a relatively larger size.  
         BACKGROUND OF THE INVENTION  
         [0003]    Channel-type duct systems are currently used to contain wiring and fiber-optic cables in commercial and industrial buildings. Duct fittings having a variety of configurations for joining separate sections of fiber duct are well known in the industry. One such duct fitting is a vertical tee fitting. The vertical tee is T-shaped fitting that joins three separate pieces of duct together, two horizontal ducts and one vertical duct. Fittings, such as the vertical tee, are designed to connect with ducts of specific dimensions. However, sometimes there is a need to use a fitting to connect ducts of different dimensions than were intended for the specific fitting. When the duct requiring connection is smaller than what was intended for the specific fitting, it is common practice in the industry to use a reducer to narrow the fitting cross-section at the junction with the smaller duct. For example, a vertical tee fitting originally designed to connect to a 4-inch×4-inch vertical duct may sometimes be needed to attach to a 2-inch×2-inch vertical duct instead. A reducer attached to this vertical tee fitting would allow this fitting to connect with the 2-inch×2-inch duct.  
           [0004]    Currently, the reducers for vertical tee fittings attach to the bottom of the vertical tee. These reducers can use over 5 inches of space below the vertical tee fitting. Meanwhile, due to the relative proximity of network racks and the like to ceilings and/or horizontal duct running overhead, vertical space may be at a premium or even completely unavailable. Thus, there is a need in the industry for a reducer that encompasses minimal space below the bottom of the vertical tee fitting.  
           [0005]    Accordingly, it is desirable to provide a reducer that occupies minimal or, preferably, no additional space below the bottom of the vertical tee fitting, or more generally, minimal or no additional space beyond the extent of a fitting. The present invention provides such a reducer, which may preferably be latchably seated completely or almost completely within the fitting and thereby uses little or no additional space.  
           [0006]    It is further desirable to provide a reducer that does not interfere with any other features or uses of the fitting. The present invention does not interfere with any other uses of the vertical tee fitting and even allows for the original covers to be used with both the vertical tee fitting and the duct that attaches to the fitting.  
         SUMMARY OF THE INVENTION  
         [0007]    To address the above-stated objectives and/or deficiencies of prior designs, there is provided a fitting for routing cables between first and second ducts in a raceway system, the first duct having a first cross-sectional dimension and the second duct having a second and different cross-sectional dimension from the first cross-sectional dimension, the fitting including a first end for attaching to the first duct, a second end for attaching to the second duct, and an insertable reducer disposable generally between the first and second ends of the fitting, the reducer for adapting the fitting to transition between the first and second cross-sectional dimensions, the reducer including a barb for bitingly engaging at least one of the ducts and retaining the at least one duct to the fitting.  
           [0008]    There is also provided a raceway system for routing cables, the raceway system including a generally horizontal duct of a first cross-sectional dimension, a generally vertical duct of a second cross-sectional dimension smaller than the first cross-sectional dimension, a fitting for connecting the horizontal and vertical ducts, and a reducer insertably disposable within the fitting for transitioning the fitting between the first and second cross-sectional dimensions, the reducer including a barb for bitingly engaging at least one of the ducts and retaining the at least one duct to the fitting.  
           [0009]    There is also provided an insertable reducer for a vertical tee fitting for connecting a pair of generally horizontal ducts and a vertical duct for routing cables within a raceway system, the reducer for narrowing the cross-sectional cable routing space within the vertical tee fitting to transition the fitting from the relatively larger cross-sectional cable routing space of the horizontal ducts to the relatively smaller cross-sectional cable routing space of the vertical duct, the reducer including a barb for bitingly engaging at least one of the ducts and retaining the at least one duct to the fitting.  
           [0010]    Also provided is a fitting for routing cables between first and second ducts in a raceway system, the first duct having a first cross-sectional dimension and the second duct having a second and different cross-sectional dimension from the first cross-sectional dimension, the fitting including a first end for attaching to the first duct, a second end for attaching to the second duct, and an insertable reducer disposable generally between the first and second ends of the fitting, the reducer for adapting the fitting to transition between the first and second cross-sectional dimensions, the reducer being disposable in the fitting such that the reducer does not extend significantly beyond the fitting in the direction of either of the ducts.  
           [0011]    There is also provided a method of using a fitting to connect a pair of horizontal ducts having a relatively larger cross-sectional dimension to a vertical duct having a relatively smaller cross-sectional dimension within a raceway system for routing cables, the method including the following steps: providing a fitting; providing a reducer insertable into the fitting, the reducer including a barb; providing first and second connectors; connecting a first end of the fitting to one of the pair of horizontal ducts with the first connector; connecting a second end of the fitting to the other of the pair of horizontal ducts with the second connector; inserting a reducer having a latch into the fitting such that the latch engages the fitting to retain the reducer in a fixed position within the fitting; and connecting a portion of the fitting proximate the inserted reducer to the vertical duct by sliding the vertical duct between portions of the reducer and the fitting such that the barb bitingly engages the vertical duct for retaining the vertical duct relative to the fitting. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    [0012]FIG. 1 is a perspective view of a vertical tee fitting for connecting relatively larger horizontal ducts with a relatively smaller vertical duct, in accordance with an embodiment of the present invention;  
         [0013]    [0013]FIG. 2 is an exploded view of the vertical tee fitting of FIG. 1;  
         [0014]    [0014]FIG. 3 is an enlarged perspective view of the reducer shown in FIG. 2;  
         [0015]    [0015]FIG. 4 is an exploded view of an alternative embodiment of a reducer in accordance with the invention;  
         [0016]    [0016]FIG. 5 is a side view of the reducer of FIG. 4; and  
         [0017]    [0017]FIG. 6 is a cross-sectional view of the reducer of FIG. 4.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0018]    Turning now to the drawings, FIGS.  1 - 2  show a vertical tee reducer  20  of the present invention positioned within a vertical tee fitting  10 . The vertical tee fitting  10  contains a vertical drop-out area  16  that connects with a first vertical duct system and creates continuous, uninterrupted channel-shaped duct between the horizontal and vertical duct systems. The vertical drop-out area  16  is defined by the floor  12  of the vertical tee fitting  10  and by the vertical walls  14  of the fitting  10 . The reducer  20  of the present invention is designed to fit snugly within this vertical dropout area  16  but not extend beyond the bottom of the vertical tee fitting  10 . A-similar reducer could be used in various types of duct fittings other than vertical tee fittings.  
         [0019]    With respect to the vertical tee fitting, in a preferred embodiment, as shown in FIG. 3, the reducer  20  has three sidewalls. These three sidewalls  22  are integrally connected to form a channel-shaped duct. These sidewalls  22  gradually flare outwards at the top and integrally extend into two flanges  24 . The flare of the sidewalls is designed to allow the flanges  24  to fit flush against the floor  12  of the vertical tee fitting  10 . Preferably, there is a 2″ bend radius control for the flare of the sidewalls  22 . However, one of skill in the art, following the EIA/TIA standards for appropriate minimum bend radii of wires and cables, would be able to design the radius of the flare of the sidewall  22  to conform to their specific vertical tee fitting  10 .  
         [0020]    The flanges  24  help position the reducer  20  within the vertical drop-out area  16  of the vertical tee fitting  10 . The flanges  24  also ensure a continuity between the floor  12  of the vertical tee fitting  10  and the new smaller vertical drop-out area  27  created by the reducer  20 , while protecting against microbends occurring in the fiber.  
         [0021]    A series of vertical ribs  25  may be formed along the bottom half of the sidewalls  22  and these ribs may provide additional stiffness, may serve as surface contact points, or may facilitate the molding of the sidewalls  22 . The sidewalls  22  have an inner surface  26  and an outer surface  28 . The inner surfaces  26  of the sidewalls  22  face each other and form the perimeter of the new smaller vertical dropout area  27 . The outer surfaces  28  of the sidewalls  22  face the vertical walls  14  and floor  12  forming the original drop-out area  16  of the vertical tee fitting  10 .  
         [0022]    The smaller vertical drop-out area  27  of the reducer  20  will form a continuous channel-shaped duct with the second smaller vertical duct  60 . This second smaller vertical duct  60  is attached to the reducer and held into place via three barbs  40 . As shown in FIG. 4, the barb  40  is comprised of a rectangular body  42 , bent inwardly to form an arm  46  at one end of the body  42  and having an eyelet  44  at the opposite end. The barb  40  bitingly engages the second vertical duct  60  and holds it into position against the outer surface  28  of the sidewalls  22  of the reducer  20 . Preferably, the arm  46  has a serrated edge, which will increase the biting engagement capability of the barb  40 .  
         [0023]    The barbs  40  are held into position against the second smaller vertical duct  60  by the barb housings  30 , which are placed along the outer surface  28  of each sidewall  22  of reducer  20 . As shown in FIGS.  3 - 6 , the barb housing  30  comprises at least two opposing L-shaped walls  31 . These L-shaped walls  31  are perpendicular to the outer surface  28  of the sidewall  22 , such that the two L-shaped walls  31  and the sidewall  22  together form a three-sided box. The two opposing L-shaped walls  31  mirror each other with the short leg of the L-shape facing one another. This allows the two L-shaped walls to form an open fourth side  32  to the box formed by the L-shaped walls and the sidewall. The two opposing L-shaped walls  31  are spaced just far enough apart to allow a barb  40  to be positioned between them.  
         [0024]    The barb  40  is positioned within the housing  30  and the edge of the arm  46  of the barb  40  may preferably touch the outer surface  28  of the sidewalls  22  of the reducer  20 . The body  42  of the barb  40  is held tight against the open side  32  of the housing  30  by two barb guides  38 . Furthermore, a barb catch  33  is inserted into the eyelet  44  of the barb  40  in order to prevent the barb  40  from being pulled out of the barb housing  30  by a downward force.  
         [0025]    A receiving space  34  is formed between the L-shaped walls  32  of the housing  30  and the outer surface  28  of the sidewalls  22  of the reducer  20 . When the second smaller vertical duct  60  is attached to the reducer  20 , one end of the second smaller vertical duct  60  is slid into the receiving space  34  so that it is positioned substantially against the outer surface  28  of the sidewall  22  within the barb housing  30 . The edge of the arm  46  of the barb  40  then engages the surface of the second smaller vertical duct  60  and holds it firmly in position so that the duct  60  does not withdraw due to inadvertently or incidentally applied forces.  
         [0026]    The barb housing further comprises a catch  36  that overlaps the bottom edge of the vertical tee fitting  10  and prevents reducer  20  the from being pushed out of position by an upward force, such as when the second smaller vertical duct  60  is attached to the reducer. The catch  36  may be part of the open side  32  of the barb housing  30 . The catch  36  may also be a separate piece attached to the outer surface  28  of the sidewall  22 . Optionally, other separate pieces, such as tabs  50 , may be attached to the outer surface  28  of the sidewalls  22 . The tabs  50  fit into slots in floor  12  of the vertical tee fitting  10  to assist in positioning the reducer  20  correctly within the vertical drop-out area  16  of the fitting  10 .  
         [0027]    The barb housing  30  provides spacing between the smaller vertical dropout area  27  of the reducer  20  and the vertical drop-out area  16  of the fitting  10 . The open side  32  of the barb housing  30  fits flush against the vertical walls  14  of the vertical tee fitting  10  to ensure that the reducer  20  is properly aligned within that vertical drop-out area  16  of the vertical tee fitting  10  and to deter the occurrence of microbends or other signal-degrading phenomena in the fiber. If the barb housing  30  does not occupy the entire space between the vertical drop-out area  27  of the reducer  20  and the vertical walls  14  of the vertical tee fitting  10 , a wall extension  39  may be attached to the open side  32  of the barb housing  30  in order to occupy this extra space and make the reducer  20  fit flush against the vertical wall  14  of the fitting  10 .  
         [0028]    Second, the catches  36  on the barb housing lock the reducer  20  into place so that it does not move out of the vertical drop-out area  16  when trying to attach the second smaller vertical duct to the reducer  20 . Although a single one may be sufficient, there is preferably a catch  36  located on each barb housing  30 .  
         [0029]    Third, the barb housing  30  holds the barb  40  in a position to maintain a strong engagement with the second smaller vertical duct  60 . The barb housing  30  positions the barb so that the edge of the arm  46  of the barb  40  is angled upwards and into the second smaller vertical duct  60 , when the second smaller vertical duct  60  is located within the receiving space  34  of the housing  30 . Due to the angle of the arm  46  of the barb  40 , a downward or withdrawal force on the second smaller vertical duct  60  would cause the edge of the arm  46  to bite harder into the surface of the second smaller vertical duct  60  and prevent the duct from moving out of the receiving space  34 . This prevents inadvertent withdrawal or slippage of the duct  60  and produces a minimum withdrawal force that must be applied to overcome the resistance capability of the barb(s) to uncouple the duct  60  from the vertical tee/reducer assembly.  
         [0030]    Because the reducer  20  of the present invention fits substantially entirely within the vertical drop-out area  16  of the vertical tee fitting  10 , it occupies no significant additional space below the fitting  10 . Additionally, a cover for the vertical tee fitting  10  may be used in the same manner with or without the reducer  20  in place because the reducer does not extend substantially past the front of the vertical tee  10 . The reducer  20  of the present invention also does not interfere with a cover for the second smaller vertical duct  60  that is attached to the reducer  20 .  
         [0031]    It should be understood that a wide range of changes and modifications can be made to the embodiments of the reducer described above. For instance, a fitting other than a vertical tee may be adapted with a reducer of the type described and claimed herein. Additionally or alternatively, the slope and/or curvature of the sidewalls, the dimensions of the barb housings, the cross-sectional dimensions of the respective ducts connected to the fitting, the number of catches, the extensions added to the housing, or the addition of tabs may be different than the exemplary embodiments described above, depending upon the specific fitting used and the consumer and manufacturing preferences.  
         [0032]    Additionally, it&#39;s easily seen that a method of wiring a fitting having a barbed reducer to connect ducts of different sizes could have steps performed equivalently in a number of different orders. For example, with respect to the vertical tee fittings described above, the reducer could be inserted into the fitting either before or after the horizontal ducts were connected to the fitting. It is therefore intended that the foregoing description illustrates rather than limits this invention, and that it is the following claims, including all equivalents, which define this invention.