Abstract:
The present invention provides modular trays having cutout features that are configured to engage with a mounting feature of one or more removable rails. The removable rails may be removeably secured to a tray body in a plurality of positions to allow a user to install or uninstall rails to support different sized fiber optic modules. For example, a tray may support a twenty-four optical fiber module, two twelve optical fiber modules, or three eight optical fiber modules. Fiber optic enclosures housing the trays can be affixed to the outside of a fiber optic enclosure and allow for easy stacking and unstacking.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 62/356,662, filed Jun. 30, 2016, the subject matter of which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates to data center management, and in particular enclosures for high speed data transport fiber cabling systems. Optical fibers allow for transmission of communications over longer distances and at higher bandwidths than wire cables. Optical fibers are also advantageous for communication systems because signals suffer less loss than wire cables and are immune to electromagnetic interference. Optical fibers are therefore often used for high bandwidth, long distance applications. One of the primary functions of a data center is to provide connections between incoming and outgoing optical fiber connections. 
         [0003]    A user may desire to use different sized fiber optic modules housing optical fiber connections. At present, such a user installs and removes entire banks of patch panels or trays in order to accommodate different sized fiber optic modules because trays are currently designed to only support one size of fiber optic module. Thus, it may be advantageous to provide a tray that allows different sized fiber optic modules to be installed within the tray without replacing or removing the tray itself. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention is directed to a tray to support fiber optic equipment. The tray includes a tray body having a first side edge portion, a second side edge portion, a front side edge portion, a rear side edge portion and a middle portion. The middle portion of the tray body has a plurality of cutout features. The first side edge portion is configured to be secured to a first rail. The second side edge portion is configured to be secured to a second rail. The cutout features are configured to engage with a mounting feature of a third rail such that the third rail may be removably secured to the tray body in a plurality of positions. 
         [0005]    Another embodiment of the present invention is directed to a system to support fiber optic equipment. The system includes a tray body having a first side edge portion, a second side edge portion, a front side edge portion, a rear side edge portion and a middle portion. The middle portion of the tray body has a first set of cutout features and a second set of cutout features. The system also includes a first rail secured to the first side edge portion, a second rail secured to the second side edge portion, and a third rail having a mounting feature configured to be removably secured to the first set of cutout features or the second set of cutout features. 
         [0006]    Another embodiment of the present invention is directed to a method of supporting a plurality of sizes of fiber optic modules. The method includes inserting a mounting feature of a rail into a first set of cutout features in a tray body. The method further includes removing the mounting feature of the rail from the first set of cutout features in the tray body. The method further includes inserting the mounting feature of the rail into a second set of cutout features in the tray body. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1A  is a perspective view of the patch panel. 
           [0008]      FIG. 1B  is an exploded view of the patch panel of  FIG. 1A . 
           [0009]      FIG. 2A  is a perspective view of the frame of the patch panel. 
           [0010]      FIG. 2B  is a front view of the frame of the patch panel. 
           [0011]      FIG. 2C  is a bottom view of the frame of the patch panel. 
           [0012]      FIG. 3  is a perspective view of the rear of the patch panel. 
           [0013]      FIGS. 4A and 4B  are perspective and side views of the center support brackets, respectively. 
           [0014]      FIG. 5  is a perspective view of the modular tray of the patch panel. 
           [0015]      FIGS. 6A, 6B, and 6C  are perspective views of the left, removable, and right rails of the patch panel, respectively. 
           [0016]      FIGS. 6D and 6E  are perspective views of the right and left rails of the patch panel, respectively. 
           [0017]      FIG. 7  is a top view of the modular tray with two modules installed in the tray. 
           [0018]      FIG. 8  is a perspective view of the modular tray with two modules installed in the tray. 
           [0019]      FIG. 9  is a top view of the modular tray with three modules installed in the tray. 
           [0020]      FIG. 10  is a perspective view of the modular tray with three modules installed in the tray. 
           [0021]      FIG. 11  is a top view of the modular tray with one module installed in the tray. 
           [0022]      FIG. 12  is a perspective view of the modular tray with one module installed in the tray. 
           [0023]      FIGS. 13A, 13B, and 13C  are top, side, and cross-section views of the removable rail of the patch panel. 
           [0024]      FIG. 14A  is a top view of a portion of the modular tray. 
           [0025]      FIG. 14B  is a cross-section view of the removable rail. 
           [0026]      FIG. 14C  is a side view of the removable rail. 
           [0027]      FIG. 15  is a top view of the modular tray with three removable rails installed in the tray. 
           [0028]      FIG. 16  is a top view of a portion of the modular tray with the right and left rails. 
           [0029]      FIG. 17  is a perspective view of the modular tray with three removable rails installed in the tray. 
           [0030]      FIG. 18  is a perspective view of a portion of the modular tray with three removable rails installed in the tray. 
           [0031]      FIG. 19  is a perspective view of the bottom of a portion of the modular tray with three removable rails installed in the tray. 
           [0032]      FIG. 20  is a perspective view of the left and right rails and three removable rails of the patch panel. 
           [0033]      FIG. 21  is cross sectional views of the three removable rails of  FIG. 15 . 
           [0034]      FIG. 22  is cross sectional views of the three removable rails of  FIG. 15 . 
           [0035]      FIG. 23  is cross sectional views of the three removable rails of  FIG. 15 . 
           [0036]      FIG. 24  is cross sectional views of the three removable rails of  FIG. 15 . 
           [0037]      FIGS. 25A and 25B  are side views of the two different removable rails shown in  FIG. 20 . 
           [0038]      FIGS. 26A and 26B  are top views of a portion of the modular tray with modules installed in the tray. 
           [0039]      FIGS. 27A and 27B  are top views of a portion of the modular tray with modules installed in the tray. 
           [0040]      FIGS. 28A and 28B  are top views of a portion of the modular tray with modules installed in the tray. 
           [0041]      FIGS. 29A and 29B  are top views of a portion of the modular tray with modules installed in the tray. 
           [0042]      FIG. 30  is a perspective view of the rear of a High Density Fiber Enclosure (“HDFE”). 
           [0043]      FIG. 31  is a perspective view of the rear of another embodiment of a HDFE. 
           [0044]      FIG. 32  is a perspective view of the rear of another embodiment of a HDFE. 
           [0045]      FIG. 33  is a perspective view of the HDFE tray with a removable rail installed in the tray. 
           [0046]      FIG. 34  is an exploded perspective view of the HDFE tray of  FIG. 33 . 
           [0047]      FIG. 35  is a perspective view of the body of the HDFE tray. 
           [0048]      FIG. 36  is a perspective view of the HDFE tray with two removable rails installed in the tray. 
           [0049]      FIG. 37  is a perspective view of body of the HDFE tray including right and left rails. 
           [0050]      FIG. 38  is a perspective view of the HDFE removable rail. 
           [0051]      FIG. 39  is an exploded perspective view of the HDFE removable rail. 
           [0052]      FIG. 40  is a bottom perspective view of a portion of a HDFE tray and a HDFE removable rail. 
           [0053]      FIG. 41  is a bottom perspective view of a portion of a HDFE tray with a HDFE removable rail partially installed in the tray. 
           [0054]      FIG. 42  is a bottom perspective view of a portion of a HDFE tray with a HDFE removable rail fully installed in the tray. 
           [0055]      FIG. 43  is a bottom perspective view of a portion of a HDFE removable rail installed in a HDFE tray. 
           [0056]      FIG. 44  is a perspective view of a HDFE enclosure. 
           [0057]      FIG. 45  is a front magnified view of the HDFE enclosure. 
           [0058]      FIG. 46  is a top view of a portion of a HDFE enclosure. 
           [0059]      FIG. 47  is an exploded perspective view of the rear of the HDFE enclosure including a removable top cover. 
           [0060]      FIG. 48  is an exploded perspective view of the rear of the HDFE enclosure including a removable top cover. 
           [0061]      FIG. 49  is a perspective view of the rear of the HDFE enclosure with the removable top cover installed. 
           [0062]      FIG. 50  is a perspective view of the HDFE enclosure with a HDFE removable rail partially installed. 
           [0063]      FIG. 51  is a side view of a HDFE modular tray with a HDFE removable rail partially installed. 
           [0064]      FIG. 52  is a bottom perspective view of the body of a HDFE modular tray with a HDFE removable rail installed in the tray. 
           [0065]      FIG. 53  is a top view of a HDFE modular tray with three modules installed in the tray. 
           [0066]      FIG. 54  is a perspective view of a HDFE modular tray with three modules installed in the tray. 
           [0067]      FIG. 55  is a top view of a HDFE modular tray with two modules installed in the tray. 
           [0068]      FIG. 56  is a perspective view of a HDFE modular tray with two modules installed in the tray. 
           [0069]      FIG. 57  is a top view of a HDFE modular tray with one module installed in the tray. 
           [0070]      FIG. 58  is a perspective view of a HDFE modular tray with one module installed in the tray. 
           [0071]      FIG. 59  is a perspective view of a modular patch panel installed on the front face of the equipment rail of a fiber optic enclosure. 
           [0072]      FIG. 60  is another perspective view of a modular patch panel installed on the side of the equipment rail of a fiber optic enclosure. 
           [0073]      FIG. 61  is a perspective view of a modular patch panel installed on the rear face of the equipment rail of a fiber optic enclosure. 
           [0074]      FIG. 62  is an exploded perspective view of the modular patch panel of  FIG. 61 . 
           [0075]      FIG. 63  is a perspective view of the modular patch panel. 
           [0076]      FIG. 64  is an exploded perspective view of the modular patch panel of  FIG. 63 . 
           [0077]      FIG. 65  is a cross sectional view of the modular patch panel prior to installation of an additional unit. 
           [0078]      FIG. 66  is a cross sectional view of the modular patch panel with all units shown in  FIG. 65  installed. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0079]    As shown in  FIGS. 1A and 1B , a patch panel  50  consists of a frame  100 , modular tray  120 , and center support brackets  170 . A plurality of removable rails  180  as shown in  FIG. 6B  may be added to or removed from the modular tray  120  in order to support differently-sized fiber optic modules  10  that support a different number of optical fibers. Referring to  FIG. 5 , in a preferred embodiment, the removable rails may be added or removed in order to support one 24-optical fiber module  20 , two 12-optical fiber modules  30 , or three 8-optical fiber modules  40 . The fiber optic modules shown in all of the Figures (for example,  FIG. 7 ) of this application include duplex LC adapters at the front of the module that lead to 1 MPO adapter at the rear of the module. The 24-optical fiber module  20  shown in the Figures includes 12 LC adapters; the 12-optical fiber module  30  as shown in the Figures includes 6 LC adapters; and the 8-optical fiber module  40  as shown in the Figures includes 4 LC adapters. One of ordinary skill in the art would understand that different numbers of optical fibers and different numbers and types of adapters may be used in a fiber optic module that may be installed within the present invention. 
         [0080]    Referring now to  FIGS. 2A, 2B, and 2C , the frame  100  includes a top cover  102 , right side  104 , left side  106 , and a bottom flange  112 . The bottom flange  112  is configured to support a modular tray  120 . The right side  104  and left side  106  of the frame each include two bridge lance features  110  disposed above the bottom flange  112 . The bridge lance features  110  are slots formed in the right side  104  and left side  106  of the frame  100  to support additional modular trays  120  in the frame  100 . In a preferred embodiment, two bridge lance features  110  are disposed in each side so that the frame  100  can support two additional modular trays  120  above the modular tray  120  supported by the bottom flange  112 . One of ordinary skill in the art would understand that the bridge lance features  110  and center support brackets  170  (described below) may have more or fewer slots that support modular trays  120 . The frame may also include holes  108  for mounting the frame  100  to fiber optic enclosure rail  4  within a fiber optic enclosure  2  and mounts  114  for cable slack management trays  8  as shown in  FIG. 3 . 
         [0081]    Referring now to  FIGS. 4A and 4B , the center support brackets  170  are comprised of a bracket body  172 , holes  174  to attach the bracket to the frame  100  and lowermost tray  120 , and notches  176  to support the additional modular trays  120  disposed in the frame  100 . In a preferred embodiment, the center support brackets  170  include two notches  176  to support two additional modular trays  120 . 
         [0082]    Referring now to  FIG. 5 , a modular tray  120  includes at least one tray body  132 , at least one set of cutout features  140  disposed in the tray body  132 , an alignment slot  134  located on the left edge  122  and right edge  124  of the tray body  132 , a left rail  150  (see  FIGS. 6A and 6E ), and a right rail  160  (see  FIGS. 6C and 6D ). As shown in  FIG. 5 , two tray bodies  132  may make up one modular tray  120 . The alignment slots  134  are each configured to receive an alignment feature  156 ,  166  located on the bottom portion  154  of the left rail  150  and bottom portion  164  of right rail  160 . As shown in  FIG. 6E , in addition to the alignment feature  156 , the left rail  150  also includes a rear latch retention feature  152  and a fiber optic module contact protrusion  158 . The rear latch retention feature  152  is configured to receive a rear fiber optic module retention latch  12  of a fiber optic module  10 . The fiber optic module contact protrusion  158  is configured to abut against a fiber optic module  10  during installation of a fiber optic module  10  as well as once the fiber optic module  10  is installed. As shown in  FIG. 6D , in addition to the alignment feature  166 , the right rail also includes a rear latch retention feature  162  and a front stop latch  168 . The front stop latch  168  is configured to retain a fiber optic module retention feature  12  when a fiber optic module  10  is fully installed in the modular tray  120 . Both the left rail  150  and right rail  160  are riveted, secured with screws, or otherwise permanently installed onto the left edge  122  and right edge  124 , respectively, of the modular tray body  132 . 
         [0083]    Referring back to  FIG. 5 , the cutout features  140  of the modular tray  120  are configured to receive a removable rail  180  in such a way that the removable rail  180  may be secured to and removed from the modular tray  120 . In a preferred embodiment, one cutout feature  120  is a set of two or more cutouts in the body of the tray  120  each shaped to receive a portion of the removable rail  180 . The cutout features  120  are preferably shaped as a larger rectangle at the portion of the cutout closest to the front of the modular tray  120  with a rear portion of the cutout that forms a slit. One set of cutout features  140  are disposed in a line parallel to the left and right rails  150 ,  160 . Preferably, three sets of cutout features  140  are disposed on the modular tray. One middle set of cutout features  146  is disposed along the midline between the left and right rails  150 ,  160 , so that, when a removable rail  180  is installed within the middle set of cutout features  146 , two 12-optical fiber modules  30  may be installed on either side of the removable rail  180  as shown in  FIGS. 7-8 . Two additional sets of cutout features, left set of cutout features  144  and right set of cutout features  142 , are disposed on either side of the middle set of cutout features  146  so that, when removable rails  180  are installed in both the left set of cutout features  144  and right set of cut out features  142 , three 8-optical fiber modules  40  may be installed into the modular tray  120  as shown in  FIGS. 9-10 . Finally, when no removable rails  180  are installed in the modular tray  120 , one 24-optical fiber module may be installed between the left rail  150  and right rail  160  as shown in  FIGS. 11-12 . 
         [0084]    Referring now to  FIGS. 13A, 13B, and 13C , the removable rails  180  include two rear latch retention features  188 , a module contact protrusion  190 , a front stop latch  192 , a front retention boss  194 , and at least one T-shaped mounting feature  196 . One rear latch retention feature  188  is disposed on the left side  182  and right side  184  of the removable rail  180 . The rear latch retention features  188 , module contact protrusion  190 , and front stop latch  192  are the same as on the left rail  150  and right rail  160 . The front retention boss  194  is disposed within the front-most portion of the front-most cutout feature  140   a  when the removable rail  180  is fully installed in a modular tray  120 . The T-shaped mounting feature  196  is located on the bottom of the removable rail  180  and includes a tapered front portion  198 . The T-shaped mounting feature is shaped so that it can be inserted into the larger rectangle portion of the cutout features  140  closest to the front of the modular tray  120  and then slid toward the back of modular tray  120  so that the T-shaped mounting feature  196  securely engages with the rear portion of the cutout features  140  that forms a slit. 
         [0085]    As shown in  FIGS. 14-24 , if different sets of cutout features  140  are disposed on the tray  120 , one or more of the sets may be slightly different—i.e. as shown in  FIGS. 17-19 , the cutout features may be of different sizes or shapes, or may be closer or further away from the front of the tray  120  than cutout features in other sets of cutout features. If this is the case, the removable rails  180  configured to be disposed in the cutout features would also be slightly different so that only a removable rail  180  designed to be installed in a particular set of cutout features  140  could be installed in that set of cutout features  140 . Such different sizes or shapes may allow for different rails to be used in different positions. Additionally, these rails of different sizes or shapes may be color coded or otherwise identified to match up the appropriate removable rail  180  to a set of cutout features  140 . 
         [0086]      FIGS. 21-24  provide cross-sectional views of the removable rails  180  installed in the modular tray  120  shown in  FIG. 15 . As can be seen in  FIG. 21 , the tapered front of the T-shaped mounting feature  198  at the rear of the center removable rail  180  is larger than the outside removable rails  180 . Similarly, as shown in  FIG. 22 , the cross-section of the center removable rail  180  is larger than the cross-section of the outside removable rails  180 . Thus, the center removable rail  180  would only fit within the middle set of cutout features  146 , and the outside removable rails  180  would only fit within the left and right sets of cutout features  142 ,  144 .  FIGS. 23 and 24  show that the second T-shaped features of the removable rails  180  have similarly-sized cross sections i.e. the tapered front  198  and cross section of the T-shaped mounting features  196  of the center removable rail  180  are larger than the tapered front  198  and cross section of the T-shaped mounting features  196  of the outside removable rails  180 . One of ordinary skill in the art would understand that this feature may be accomplished in many other ways—for example, the middle set of cutouts  146  and T-shaped mounting feature  196  of the middle removable rail  180  may be disposed slightly closer to the front if the modular tray  120  than the left and right sets of cutouts  242 ,  244  and the T-shaped mounting features  196  of the left and right removable rails  180 . 
         [0087]    As shown in  FIGS. 25A and 25B , in which the removable rail  180  is fully installed in  FIG. 25A , in order to install a removable rail  180  into a modular tray  120 , the T-shaped mounting feature(s)  196  of the removable rail  180  are inserted through the larger portion of the cutout features  140  in one set of cutout features. The removable rail  180  is then slid toward the back of the modular tray  120  until the T-shaped mounting feature  196  is secured within the narrower portion of the cutout features  140 . When the T-shaped mounting features  196  reach the rear-most portion of the cutout features  140 , the front retention boss  194  slides into and abuts the front of the front-most cutout  140   a . Thus, the front retention boss  194  secures the removable rail  180  in the modular tray  120 . In order to remove the removable rail  180 , a user first uses his hand or other tool to press the front retention boss  194  upward past the front of the front-most cutout  140   a . Once the front retention boss  194  clears the front-most cutout  140   a , the removable rail  180  may be slid toward the front of the modular tray  120  until the T-shaped features  196  of the removable rail  180  are located in the larger portion of the cutout features  140 . The removable rail  180  is then no longer secured to the modular tray  120  and may be removed. 
         [0088]    As shown in  FIGS. 26A and 26B , once the removable rail  180  is installed, fiber optic modules  10  may be installed onto the tray  120  in a conventional manner. In particular, to install a fiber optic module  10  from the front of the fiber optic enclosure  2 , a user pushes the fiber optic module  10  from the front of the enclosure into a space on the tray formed by two of the rails installed on the modular tray  120 . The user continues pushing the fiber optic module  10  into the space until the front retention feature  14  of the fiber optic module  10  seats within a front stop latch  168  or  192 . As shown in  FIGS. 27A and 27B , to uninstall a fiber optic module  10  from the front of the enclosure  2  a user pushes the front stop latch  168  or  192  to the right to release the fiber optic module  10 . The user then pulls the fiber optic module  10  toward the front of the fiber optic enclosure  2 . 
         [0089]    Referring now to  FIGS. 28A and 28B , to install a fiber optic module  10  from the rear of the fiber optic enclosure  2 , the user pushes the fiber optic module  10  from the rear of the enclosure  2  into a space on the tray  120  formed by two of the rails installed on the modular tray  120 . The user continues pushing until the rear module retention latches  12  of the fiber optic module  10  seat in the rear latch retention features  152 ,  162 , or  188  of the rails. As shown in  FIGS. 29A and 29B , to uninstall a fiber optic module  10 , a user squeezes the rear module retention latches  12  of the module toward each other until the fiber optic module  10  is released from the rear latch retention features  152 ,  162 , or  188 . The user then continues to pull the fiber optic module  10  toward the rear of the fiber optic enclosure  2 . 
         [0090]    Another embodiment of the present invention, a High Density Fiber Enclosure (HDFE)  200  that includes a modular tray and removable rail design is described below. As shown in  FIGS. 30-32 , the High Density Fiber Enclosure  200  includes a top cover  202 , bottom portion  212 , and mounting for cable slack management  214 . As further shown in  FIG. 33 , the HDFE  200  also includes a HDFE modular tray  220  that includes at least one tray body  232 , HDFE cut out features  240 , alignment pins  234 , alignment holes  230 , metal tabs  236 , a HDFE left rail  250 , a HDFE right rail  260 , and two labels  16  (shown in  FIGS. 36-37 ). One alignment pin  234  each is located on the left edge  222  and right edge  224  of the HDFE modular tray  220  and passes through an alignment hole  230 . The alignment pins  234  are self-clinching and are configured to engage with a hole in a HDFE left rail  250  and right rail  260 , respectively, to align the HDFE left rail  250  and right rail  260  with the left edge  222  and right edge  224  of the HDFE modular tray  220 . The alignment pins  234  may be self-tapping screws or another suitable fastener known in the art. A metal tab  236  is located at the front-most portion of the left edge  222  and right edge  224  of the HDFE modular tray  220 . The metal tab  236  extends upward at a 90 degree angle to the HDFE modular tray  220  and secures the front portion of the HDFE left rail  250  and right rail  260 . The labels  16  are disposed on the front  226  of the HDFE tray  220 . 
         [0091]    The HDFE left rail  250  and HDFE right rail  260  are both permanently secured to the left edge  222  and right edge  224  respectively of the HDFE modular tray  220 . The HDFE left rail  250  and HDFE right rail  260  also both include a metal spring clip  252 ,  262  for retaining a fiber optic module  10 . The metal spring clip  252  is disposed on the right side  256  of the HDFE left rail  250 , and the metal spring clip  262  is disposed on the left side  266  of the HDFE right rail  260  so that the metal spring clips  252 ,  262  face one another. 
         [0092]    The HDFE cutout features  240  are formed to removably receive HDFE removable rails  280 . As shown in  FIGS. 33-37 , a HDFE cutout feature  240  is a set of two or more cutouts in the body of the tray  220  each shaped to receive a portion of the HDFE removable rail  280 . The set of cutout features  240  are disposed in a line parallel to the left and right rails  250 ,  260 . In a preferred embodiment four cutouts comprise one set of cutout features  240 . The rear-most cutout  240   a  is triangularly-shaped so that the triangle points toward the rear  228  of the HDFE modular tray  220 . The middle cutout  240   b  is formed of an overlapping larger and smaller rectangle, where the smaller rectangle is configured to securely hold a portion of the HDFE removable rail  280 . The final two cutouts are disposed proximate to one another near the front  226  of the HDFE modular tray  220 . The forward-most cutout  240   d  is formed of two ovals cut out of the HDFE modular tray  220 . One of the ovals is larger than the other, and the ovals overlap so that a self-clinching keyhole fastener  284  of a removable rail  280  may be inserted into the larger oval portion of the forward-most cutout  240   d  and then slid over to be secured in the smaller oval portion of the forward-most cutout  240   d . The final cutout, the latch-receiving cutout  240   c , is located just to the rear of the forward-most cutout  240   d  and is configured to receive a latch  290   c  located on the HDFE removable rail  280 . One embodiment of the latch-receiving cutout  240   c  is a rectangular-shaped cutout. 
         [0093]    Referring now to  FIGS. 38 and 39 , the HDFE removable rail  280  includes a metal bracket  282 , two metal spring clips  286 , a cassette guide  290 , and protrusions for engaging with the cutout features on the HDFE modular tray  220 . The metal bracket  282  extends along the bottom portion  296  of the cassette guide  290  and includes a self-clinching keyhole fastener  284  for engaging with the forward-most cutout  240   d  of the HDFE modular tray  220 . The two metal spring clips  286  are disposed on either side of the HDFE removable rail  280 . The cassette guide  290  is disposed on top of the metal bracket  282  and includes several protrusions for engaging with the cutout features on the HDFE modular tray  220  as described below. One of ordinary skill in the art would understand, and it is contemplated by this invention, that the HDFE removable rail  280  could also be formed of just one piece and/or could be made of one material. Moreover, HDFE removable rail  280  could be color-coded for easy identification by a user. 
         [0094]    As shown in  FIGS. 40-43 , the protrusions for engaging with the cutout features on the HDFE modular tray  220  include a front latch  290   c , a middle protrusion  290   b , and a rear protrusion  290   a . The front latch  290   c  includes a latching portion which extends in the direction of the HDFE modular tray  220  when the HDFE removable rail  280  is installed in the HDFE tray  220  so that the HDFE removable rail  280  may not be moved side to side upon the HDFE removable tray  220 . The front latch  290   c  is disposed on the front portion  292  of the cassette guide  290 . The latching portion of the front latch  290   c  extends into the latch-receiving cutout  240   c  to lock the HDFE removable rail  280  to the HDFE modular tray  220 . The middle protrusion  290   b  is formed to engage with the middle cutout  240   b  and disposed between the front  292  and rear  294  portions of the cassette guide  290 . The middle protrusion  290   b  is preferably T- or I-shaped so that the top of the T or I of the middle protrusion  290   b  is disposed through the middle cutout  240   b  when the HDFE removable rail  280  is installed in the HDFE modular tray  220 . The rear protrusion  290   a  is formed to engage with the rear-most cutout  240   a  and disposed on the rear  294  of the cassette guide  290 . The rear protrusion  290   a  is formed so that the rear portion of rear protrusion  290   a  engages with the triangularly-shaped rear-most cutout  240   a  so that the HDFE removable rail  280  can pivot in a plane parallel to the HDFE modular tray  220 . 
         [0095]    As shown in  FIGS. 44-46 , portions of the bottom portion  212  of the HDFE enclosure  200  may be raised. One of ordinary skill in the art would understand that these raised or beaded portions are typically included in an enclosure to strengthen the enclosure. However, the beads  212   a  that run parallel to the rails  250 ,  260 , and  280  also provide clearance between the HDFE tray  220  and the bottom portion  212  of the HDFE enclosure  200 . This provides a space for the protrusions  290   a ,  290   b , and  290   c  of the HDFE removable rail  280  to move within when a HDFE removable rail  280  is installed within an HDFE tray  220 . Other shapes and types of beads  212   a  are contemplated by this disclosure. 
         [0096]    As shown in  FIGS. 46-47 , the top cover  202  of the HDFE enclosure  200  is cut away above the mounting for cable slack management  212 . In one embodiment of the disclosed invention, this cut away portion may be covered by a removable top cover  202   a  as shown in  FIGS. 47-49 . 
         [0097]    The sets of cutouts features  240  in the HDFE modular tray  220  and protrusions on the HDFE removable rail  280  may be slightly different so that only a particular HDFE removable rail  280  may be secured within a set of cutout features  240  as previously described with respect to the patch panel embodiment. For example, the middle set of cutouts  246  may be disposed slightly closer to the front of the HDFE modular tray  220  than the left and right sets of cutouts  242 ,  244 , and the protrusions on the HDFE removable rail  280  may be disposed closer to the front of the HDFE removable rail  280 . 
         [0098]    Referring now to  FIGS. 50-52 , in order to insert the HDFE removable rail  280  into the HDFE modular tray  220 , a user first positions the HDFE removable rail  280  so that all of the protrusions  290   a ,  290   b ,  290   c  and the self-clinching keyhole fastener  284  are disposed within one set of cutout features  240 . The user then pushes the removable rail  280  toward the rear of the HDFE tray  220  to seat the rear-most protrusion  290   a  into rear of the rear-most cutout  240   a . Maintaining the protrusions  290   a ,  290   b ,  290   c  and self-clinching keyhole fastener  284  in corresponding cutouts  240   a ,  240   b ,  240   c , and  240   d , the user then rotates the HDFE removable rail  280  so that the middle protrusion  290   b  is moved into the smaller portion of the middle cutout  240   b . As this occurs, the front latch  290   c  seats within the latch-receiving cutout  240   c  to secure the HDFE removable rail  280  in the HDFE modular tray. The self-clinching keyhole fastener  284  seats in cutout  240   d  at this time as well. In order to remove the HDFE removable rail, the user depresses and releases the front latch  290   c , rotates the HDFE removable rail  280  slightly so that the front latch  290   c , middle protrusion  290   b , and self-clinching keyhole fastener  284  are no longer seated in the latch-receiving cutout  240   c , the smaller portion of the middle cutout  240   b , and the smaller portion of forward most cutout feature  240   d . The user then pulls HDFE removable rail  280  slightly forward, lifts, and removes the HDFE removable rail  280  from the HDFE modular tray  220 . 
         [0099]    Preferably, three sets of cutout features  240  are disposed on the HDFE tray. One middle set of cutout features  246  is disposed along the midline between the left and right rails  250 ,  260 , so that, when a removable rail  280  is installed within the middle set of cutout features  246 , two 12-optical fiber modules  30  may be installed on either side of the removable rail  280  as shown in  FIGS. 55-56 . Two additional sets of cutout features, left set of cutout features  244  and right set of cutout features  242 , are disposed on either side of the middle set of cutout features  246  so that, when removable rails  280  are installed in both the left set of cutout features  244  and right set of cut out features  242 , three 8-optical fiber modules  40  may be installed into the HDFE tray  220  as shown in  FIGS. 53-54 . Finally, when no removable rails  280  are installed in the HDFE tray  220 , one 24-optical fiber module  20  may be installed between the left rail  250  and right rail  260  as shown in  FIG. 57-58 . 
         [0100]    One of ordinary skill in the art would understand that the cutout features  140  and removable rails  180  described with respect to the patch panel  50  could be used within the High Density Fiber Enclosure  200 , and that the HDFE cutout features  240  and HDFE removable rail  280  could be used with the patch panel  50 . Moreover, one of ordinary skill in the art would understand that differently shaped cutouts and removable rail mount shapes could be used in either the patch panel  50  or High Density Fiber Enclosure  200 . These additional modular tray and removable rail designs are contemplated and included within this description. 
         [0101]    Finally, a modular patch panel that may include removable rails described above is also disclosed. Referring now to  FIGS. 59-63 , the modular patch panel  500  includes at least one unit  600  that can be attached to a fiber optic enclosure equipment rail  4  or another unit  600 , a post mounting bracket  700 , and a mounting plate  800 . A unit  600  includes four hooks  610 , four openings  612 , a cantilever latch  614 , a mating hole  616 , and a cutout  618 . The four hooks  610  are disposed on the top portion  602  of the unit  600 . Two of the hooks  610  are disposed on the left edge  606  of the unit  600  so that the hooks face the same direction. Two of the hooks  610  are disposed on the right edge  608  of the unit  600  so that the hooks  610  face the same direction as the hooks  610  disposed on the left edge  606  of the unit  600 . The four holes  612  are disposed through the bottom portion  604  of the unit  600 . The holes  612  are configured to slidably receive the four hooks  610  of a different unit  600  to secure the units  600  together. One of ordinary skill in the art would understand, and it is contemplated in this invention, that hooks  610  of different shapes, or even posts or other protrusions, could be used to engage with holes  612 . 
         [0102]    The cantilever latch  614  is disposed between two of the hooks  610  on the right edge  608  of the unit  600  and includes a cantilevered portion  620 . The cantilevered portion  620  faces the opposite direction of the hooks  610  and is configured to lock the units  600  to one another when the hooks  610  are fully installed in the holes  612  by engaging with the mating hole  616  of another unit  600 . The mating hole  616  is disposed on the bottom portion  604  of each unit  600 , and the cantilever latch  614  is disposed on the top portion  602  of each unit  600 . A cutout  618  in each unit  600  allows a user to reach between the units  600  to depress and release the cantilever latch  614 . The units  600  may be stacked and secured to one another as discussed below to add additional mounting for fiber optic trays and modules outside a fiber optic enclosure  2 . 
         [0103]    The bottom-most unit  600  can be attached to a fiber optic equipment enclosure rail  4  by using a post mounting bracket  700  and a mounting plate  800 . The post mounting bracket  700  is designed to be secured to the fiber optic equipment enclosure rail  4  using the mounting holes already existing in the enclosure rail  4 . The mounting plate  800  is secured to the post mounting bracket  700  and includes four hooks  810  and a cantilever latch  814 . The hooks  810  and cantilever latch  814  are all configured to be the same as the hooks  610  and cantilever latch  614 . A unit  600  may also include a label card  902  and label card holder  900  for identifying the particular unit  600 . 
         [0104]    Referring now to  FIGS. 64-66 , to install a set of units  600  on the front or rear face of an equipment rail  4  of a fiber optic enclosure  2 , the user first installs the post mounting bracket  700  using the pre-existing mounting holes on the fiber optic equipment enclosure rail  2 , corresponding holes on the post mounting bracket  700 , and bolts or screws to secure the post mounting bracket  700  to the rail  4  as shown in  FIG. 62 . A user then installs the mounting plate  800  onto the post mounting bracket  700  using bolts or screws. Once the post mounting bracket  700  and mounting plate  800  are secure, the user can attach a first unit  600  to the mounting plate  800  by positioning the mounting holes  612  of the unit  600  over the hooks  810  of the mounting plate  800 . The user then slides the unit  600  with respect to the mounting plate  800  so that the edge of each the mounting holes  612  is positioned within the crook of each of the hooks  810 . When the edge of the mounting holes  612  touches the back of the hooks  810 , the cantilever latch  814  of the mounting plate  800  is positioned within the mating hole  616  of the unit  600  and the cantilevered portion  820  abuts the edge of the mating hole  616  to secure the unit  600  to the mounting plate  800 . The first unit  600  may be pre-installed by a manufacturer on the post mounting bracket  700  and mounting plate  800 , such that a user may simultaneously install the first unit  600 , mounting bracket  700 , and mounting plate  800 . A second unit  600  may be installed on the first unit  600  by positioning the hooks  610  of the first unit within the mounting holes  612  of the second unit  600 , and sliding the second unit  600  relative to the first unit  600  until the hooks  610  and cantilever latch  614  are positioned in their corresponding holes as discussed above. 
         [0105]    To remove a unit  600  from a stack of units  600  installed together, the user uses his hand or a tool to depress the cantilever latch  614  and release the top-most unit  600 . The user then slides the unit  600  until the hooks  610  no longer engage the mounting holes  612 . The unit  600  may then be removed from the stack of units  600 . 
         [0106]    Furthermore, while the particular preferred embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from the teaching of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only and not as limitation.