FIBER MANAGEMENT SHELF HAVING REMOVABLE DOOR, PUSH-PUSH FASTENING ELEMENTS, STACKABLE SIDE RETAINER RINGS AND REDUCED

PROFILE FRONT RETAINER RINGS

FIELD OF THE INVENTION

The present invention is directed to a fiber management shelf having a removable door, push-push fastening elements, stackable side retainer rings and reduced profile front retainer rings. BACKGROUND OF THE INVENTION

Data centers that support one or more businesses, factories or residential areas typically comprise one or more racks or cabinets filled with interconnection sites for optical fibers and fiber optic cables. In a typical installation, fiber optic cables that include multiple optical fibers from an external source (these are often known as "outside plant" or "OSP" fibers) enter the cabinet and are spliced together with individual optical fibers known as "pigtails." Splicing typically occurs in a splice tray or similar component that includes multiple splice sites. The pigtail fibers are then connected within the cabinet to standard termination sites. The termination sites include termination ports that connect optically with "jumper" optical fibers that exit the rack or cabinet to supply data or other information in optical form to the remainder of the building or site. The termination sites can be provided in a number of forms, including fiber distribution cartridges, fiber distribution modules, multi-position adapter couplers and/or bezels.

Fiber management shelves are often provided a front door for providing selective access to the termination sites and elements near the front of the shelf and/or a rear door providing selective access to the splice panel and elements at the rear of the shelf. These doors may be easily opened and closed as needed. However, for some actions, including installing or removing termination sites or working on the splice panel, it may be useful to completely remove the front or rear door. Sometimes removal is required to add or remove elements from the splice panel; sometimes door removal merely makes it faster or easier to work on the interior of the splice panel. In either case, it may be necessary to remove screws and/or hinge assemblies, which may be spring biased and include multiple parts, from the shelf.

The front doors of fiber management shelves may be provided with latches or other mechanisms that must be manipulated with one or both hands in order to open the doors and/or fasten them securely. These latches can add to the complexity of fiber management shelves, and the latches on one fiber management shelf may interfere with the operation of the doors of adjacent fiber management shelves when the shelves are arranged one above another in a rack. Other types of latches may require a significant amount of force to release, and thus a user might have to pull forcefully on the door equipped with such a latch, possibly jarring the shelf and affecting the operation of the sensitive fiber optic components contained therein. It is also possible to provide fiber management shelves with doors that do not include latches, but this can lead to the undesirable condition of the doors coming open at unwanted times and failing to provide projection for the components they are intended to cover.

Additionally, a support or trough may be provided on the fiber management shelf in front of the termination sites. Patch cords leaving the termination sites are often routed along the support toward the side of the shelf. A plurality of patch cords 900 exiting termination sites 902 mounted in a shelf 904 having an opening 905 are illustrated in Figure 26. It is known to provide fiber retainer rings 906, illustrated in Figure 25, for retaining and organizing the patch cords 900 leaving each of the plurality of horizontally aligned termination sites 902. These rings may be flexible and include a gap 908 that can be opened sufficiently wide to allow the patch cords 900 to be inserted and removed. These retainers 906 are mounted in close proximity to the termination sites and generally must be removed when a termination site is added to or removed from the shelf to avoid interfering with the installation and/or removal of the termination site. It may also be difficult to access the patch cords closest to the retainer rings because of the small space between the retainer rings and the termination sites. Placing the fiber retainer rings further away from the termination sites might reduce such problems but would disadvantageously increase the size of the shelf assemble.

Additional fiber retainer rings may be provided at each side of the trough for retaining bundles of optical fibers from a given row on the fiber management shelf and guiding them toward vertical bundles of fibers that run along the side of the fiber management shelve, especially when multiple fiber management shelves are arranged one above another in a rack. The fiber retainer rings at the sides of the shelves may be supported on the trough or attached to a vertical wall of the fiber management shelf.

It would be desirable to provide a fiber management shelf with a door that can be removed and reattached without tools which door still performs the functions of conventional doors on fiber management panels. It would also be desirable to provide a fiber management shelf with latchable doors that can be latched and unlatched with one hand, without pulling on the shelf, and that do not interfere with the operation of the doors of adjacent fiber management shelves stacked above or below the fiber management shelf equipped with such latches. In addition, it would be desirable to provide an improved fiber retainer that can be mounted in a high density manner and that is configured to securely retain fibers passing therethrough and facilitate the insertion and removal of optical fibers therefrom when required and that is furthermore easy to use and that does not significantly interfere with the mounting and removal of termination sites or with accessing certain patch cords connected to the termination sites. SUMMARY OF THE INVENTION

These problems and others are addressed by the present invention, various aspects of which are addressed below:

A first aspect of which comprises a fiber management shelf having a housing with an opening, a door pivotably mounted on the housing and shiftable from a first position substantially covering the opening to a second position allowing access to the opening past an intermediate position between the first position and the second position, and a hinge connecting the door to the housing. The hinge includes at least one hinge pin that is located on one of the housing and the door and at least one receiver configured to receive and rotatably support the at least one hinge pin that is located on the other one of the housing and the door. The receiver comprises a channel having a length and first and second sides defining a channel opening having a first channel width and at least one boss on the first or second channel side, and the channel has a second channel width at the boss less than the first channel width. The hinge pin has a length and a first portion having a first hinge pin width in a first direction and a second hinge pin width in a second direction less than the first hinge pin width, and the first hinge pin width is greater than the second channel width and the second hinge pin width is less than the second channel width.

Another aspect of the invention comprises a fiber management shelf that includes a housing having an opening, a door pivotably mounted on the housing and shiftable from a first position substantially covering the opening to a second position allowing access to the opening past an intermediate position between the first position and the second position, and a hinge mechanism for pivotably supporting the door on the housing for motion from the first position to the second position, the hinge mechanism preventing the door from being removed from the housing except when the door is in the intermediate position.

A further aspect of the invention comprises a method of using a fiber management shelf as described above that includes pivoting the door from the first position to the intermediate position and removing the door from the housing by pulling the at least one hinge pin through the channel opening and past said at least one boss.

Yet another aspect comprises an optical fiber management shelf that includes a housing having a first opening, a fiber optic termination module mounted in the fiber management shelf, a first door pivotably mounted on the housing and movable from a first position substantially covering the first opening to a second position allowing access to the first opening, and at least one push-push fastener releasably securing a first portion of the first door to the housing.

Still another aspect of the invention comprises an optical fiber management shelf that includes a housing having a first opening, a fiber optic termination module mounted in the fiber management shelf and a first door pivotably mounted on the housing and pivotable about an axis from a first position substantially covering the first opening to a second position allowing access to the first opening. The first door includes a first projection, and there is a first receiver on the housing configured to receive and selectively retain the first projection to releasably secure the first door to the housing. The first receiver includes a latch configured to retain the first projection when the first projection is inserted into the first receiver and configured to release the first projection when the first door, while the first projection is retained in the first receiver, is pressed toward the first receiver.

A further aspect of the present invention comprises an optical fiber management shelf that includes a housing having a first opening on a first side of the housing and a second opening on a second side of the housing opposite from the first side of the housing with a fiber optic termination module mounted in the first opening and a fiber optic splice panel mounted in the second opening. A first door is pivotably mounted on the housing and is movable from a first position substantially covering the first fiber optic termination module to a second position allowing access to the fiber optic termination module, and a second door is pivotably mounted on the housing and is movable from a first position substantially covering the splice panel to a second position allowing access to the splice panel. The first door includes a first projection and a second projection and the second door includes a third projection and a fourth projection. The housing includes a first receiver and a second receiver configured to receive and selectively retain the first projection and the second projection to releasably secure the first door to the housing. The first receiver and second receiver each include a latch configured to retain the first projection and the second projection, respectively, when the first projection is inserted into the first receiver and the second projection is inserted into the second receiver and configured to release the first projection and the second projection when the first door, while the first projection and second projection are retained by the first receiver and the second receiver, respectively, is pressed toward the housing. The first door is sufficiently rigid that pressing the first door toward the housing at a point between the first projection and the second projection when the first projection is retained in the first receiver and the second projection is retained in the second receiver releases the first projection from the first receiver and releases the second projection from the second receiver. The second door is sufficiently rigid that pressing the second door toward the housing at a point between the third projection and the fourth projection when the third projection is retained in the third receiver and the fourth projection is retained in the fourth receiver releases the third projection from the third receiver and releases the fourth projection from the fourth receiver. The first opening includes a bottom edge and a top edge, the first door includes a bottom edge pivotably mounted at the first opening bottom edge, and the first projection and the second projection are located on the first door at a location closer to the first door top edge than to the first door bottom edge. The second opening includes a bottom edge and a top edge, the second door includes a bottom edge pivotably mounted at the second opening bottom edge, and the third projection and the fourth projection are located on the second door at a location closer to the second door top edge than to the second door bottom edge. The first projection and the second projection are integrally molded with the first door and the third projection and the fourth projection are integrally molded with the second door.

Yet a further aspect comprises an optical fiber retainer that includes a first split band of material having a bottom, a top, a front and a back surrounding an interior passage through the first band from a first side of the first band to a second side of the first band. The front includes a front first portion depending from the top and having a bottom edge facing away from the top and a front second portion extending from the bottom and including a top edge facing away from the bottom, the top edge and bottom edge constituting a first split of the first split band. The bottom includes an inner surface comprising a wall of the interior passage and an outer surface facing away from the interior passage, and the top includes an inner surface comprising a wall of the interior passage and an outer surface facing away from the interior passage, while the bottom outer surface includes a first connector element and the top outer surface includes a second connector element configured to releasably mate with another connector element of another split band.

Another aspect of the invention comprises an optical fiber retainer that includes a first split band of material having a bottom, a top, a front and a back surrounding an interior passage through the first band from a first side of the first band to a second side of the first band. The front includes a front first portion depending from the top and having a bottom edge facing away from the top and a front second portion extending from the bottom and including a top edge facing away from the bottom. The top edge and bottom edge constitute a first split of the first split band. The back includes a back first portion depending from the top and having a bottom edge facing away from the top and a back second portion extending from the bottom and including a top edge facing away from the bottom, and the top edge and bottom edge of the back constitute a second split of the first split band. The back further includes a first fastener element on the back first portion and a second fastener element on the back second portion complementary to the first fastener element and releasably connecting the back first portion to the back second portion, and the first fastener element comprises a first one of a projection and a receiver and the second fastener element comprises the other of the projection and the receiver. The receiver comprises an opening having a side wall and a slot in the side wall, and the projection has a flange extending into the slot.

Still a further aspect of the invention comprises an optical fiber retainer that includes first and second split bands of material each of which includes a bottom, a top, a front and a back surrounding an interior passage through the band from a first side of the band to a second side of the band. The front includes a first portion depending from the top and having a bottom edge facing away from the top and a second portion extending from the bottom and including a top edge facing away from the bottom, and the top edge and bottom edge constitute a first split of the split band. The back includes a hinge mechanism for changing a separation between the front top edge and the front bottom edge. The bottom includes an inner surface comprising a wall of the interior passage and an outer surface facing away from the interior passage and the top including an inner surface comprising a wall of the interior passage and an outer surface facing away from the interior passage. The retainer also includes connector means for releasably connecting the first split band top to the second split band bottom.

Another aspect of which comprises a fiber retainer ring that includes a bottom wall having a first end and a second end, a side wall projecting from the bottom wall first end and including a distal end, and a top wall connected to the bottom wall second end and forming a ramp inclined relative to the bottom wall.

A further aspect of the invention comprises a fiber retainer ring formed from a continuous strip of flexible material. The strip includes a strip first end portion which has a first end having an edge and a second end, and a bottom portion extending generally perpendicularly from the first end portion second end. The bottom portion has a first end at the second end of the first end portion and a second end, and the strip includes a cusp at the bottom portion second end turning away from the bottom portion. The strip also includes a top portion extending from the cusp at an acute angle to the bottom portion that overlies the bottom portion, and the top portion has a first end at the cusp and a second end. The strip also includes a strip second end portion extending from the top portion second end toward the bottom portion, and the strip second end portion includes an edge.

Yet a further aspect of the invention comprises a method of installing a fiber optic module in a shelf supporting a wedge-shaped fiber retainer ring as described above, which method includes aligning the fiber optic module with an opening on the shelf, placing the module on the ramp formed by the fiber retainer ring top wall, sliding the module along the ramp and into position on the shelf, and securing the module to the shelf. BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the invention will be better understood after a reading of the following detailed description together with the attached drawings, wherein:

Figure 1 is a perspective view of a housing and a removable door of a fiber management shelf according to an embodiment of the invention.

Figure 2 is a perspective view of the housing and door of Figure 1 with the door detached from the housing.

Figure 3 is a sectional side elevational view of the door and housing of Figure 1 with the door in a closed position.

Figure 4 is a sectional side elevational view of the door and housing of Figure 1 with the door in a partially open, intermediate, position.

Figure 5 is a sectional side elevational view of the door and housing of Figure 1 with the door in an open position.

Figure 6 is a perspective view of a housing and a removable door of a fiber management shelf according to another embodiment of the invention.

Figure 7 is a side elevational view of an optical fiber management shelf having front and rear doors with push-push fasteners according to another embodiment of the present invention.

Figure 8 is a front perspective view of the optical fiber management shelf of Figure 7.

Figure 9 is a rear perspective view of the optical fiber management shelf of Figure 7.

Figure 10 is an enlarged elevational view, partly in section of the push-push fastener of Figure 7.

Figure 1 1 is a front perspective view of an optical fiber management shelf according to another embodiment of the present invention.

Figure 12 is a front perspective view of an optical fiber management shelf according to another embodiment of the present invention.

Figure 13 is a front three-quarter perspective view of a fiber retainer according to another embodiment of the present invention.

Figure 14 is an exploded rear three-quarter perspective view of a fiber retainer of Figure 13.

Figure 15 is a front three-quarter perspective view of first and second stacked ones of the fiber retainers of Figure 13.

Figure 16 is an exploded view of the fiber retainer of Figure 13 showing the bottom of the retainer and a support to which the fiber retainer attaches.

Figure 17 is a sectional side view of the components of Figure 16 in an assembled state.

Figure 18 is a perspective view of a fiber retainer ring according to another embodiment of the present invention.

Figure 19 is a side elevational view of the fiber retainer ring of Figure 18.

Figure 20 is a front elevational view of the fiber retainer ring of Figure 18.

Figure 21 is a sectional elevational view taken along line 21-21 in Figure 20.

Figure 22 is front perspective view of a termination site being mounted in a shelf that includes a plurality of the fiber retainer rings of Figure 18.

Figure 23 is a side elevational view of the termination site of Figure 22 being installed in the shelf of Figure 22 over the top of one of the fiber retainer rings.

Figure 24 is flow chart illustrating a method according to another embodiment of the present invention.

Figure 25 is a side elevational view of a conventional fiber retainer ring.

Figure 26 is a perspective view of a termination site mounted in a shelf that includes conventional fiber retainer rings. DETAILED DESCRIPTION

The present invention now is described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Like numbers refer to like elements throughout. In the figures, the thickness of certain lines, layers, components, elements or features may be exaggerated for clarity.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the specification and relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein. Well-known functions or constructions may not be described in detail for brevity and/or clarity.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. As used herein, phrases such as "between X and Y" and "between about X and Y" should be interpreted to include X and Y. As used herein, phrases such as "between about X and Y" mean "between about X and about Y." As used herein, phrases such as "from about X to Y" mean "from about X to about Y."

It will be understood that when an element is referred to as being "on", "attached" to, "connected" to, "coupled" with, "contacting", etc., another element, it can be directly on, attached to, connected to, coupled with or contacting the other element or intervening elements may also be present. In contrast, when an element is referred to as being, for example, "directly on", "directly attached" to, "directly connected" to, "directly coupled" with or "directly contacting" another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed "adjacent" another feature may have portions that overlap or underlie the adjacent feature.

Spatially relative terms, such as "under", "below", "lower", "over", "upper", "lateral", "left", "right" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is inverted, elements described as "under" or "beneath" other elements or features would then be oriented "over" the other elements or features. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the descriptors of relative spatial relationships used herein interpreted accordingly. REMOVABLE DOOR

Figures 1 and 2 illustrate a fiber management shelf 10 that includes a housing 12 having a floor 14 with a radiused edge 16 and a door 18 attached to the housing 12 near edge 16 for selectively allowing access to opening 20 in the housing. As used herein, "housing" refers to the elements surrounding a plurality of fiber optic components and may comprise the floor of a fiber optic management shelf, the side walls of the fiber optic management shelf or a rack (not illustrated) in which the shelf is mounted, and/or a top wall that may be formed by another element mounted above the fiber optic management shelf in a rack. The housing may also be defined at least in part by one or more fiber retainer rings mounted near either side of the door at the front of a fiber management shelf. Door 18 is removably attached to housing 12 by a hinge, indicated generally by reference numeral 22, and includes an inner surface 24 that will face opening 20 when door 18 is in a closed position, a proximal edge 26 that remains close to radiused edge 16 of floor 14 and a distal edge 27 that moves toward and away from housing 12 when door 18 pivots between open and closed positions as described herein. Two hinges 22 are illustrated in Figure 1 at the left side of a door, and a second pair of hinges (not illustrated) is present on the right side of the door. The hinges 22 are substantially identical, and only one hinge 22 is described below.

Hinge 22 comprises a hinge pin 28 on door 18 and a receiver 30 on housing 12. Hinge pin 28 includes first and second generally cylindrical ends 32 and a central portion 34 with first and second flattened, parallel portions 36 which are spaced apart from each other a distance less than the diameter of the cylindrical ends 32 of hinge pin 28. First and second arcuate portions 37 connect the flattened portions 36 and generally conform to the curvature of the cylindrical ends 32. The distance between the first and second arcuate portions 37 is the same as the diameter of the first and second cylindrical ends 32; the distance between the flattened portions 36 is less than the diameter of the first and second cylindrical ends 32. First and second arms 38 connect to first and second ends 32 of hinge pin 28 to support hinge pin 28 in a spaced relation above inner surface 24 of door 18 and extending at least partially beyond the plane of the proximal edge 26 of door 18. The first and second arms 38 include a first surface 40 that faces toward door inner surface 24 and a second surface 42 that faces away from door inner surface 24, and both first surface 40 and second surface 42 are generally parallel to inner surface 24 of door 18.

Receiver 30 comprises a channel 44 having an opening 46 with spaced apart, generally parallel side walls 48 having upper edge 50. The distance between side walls 48 at upper edge 50 is greater than the diameter of hinge pin 28, while the interior of the channel is configured to substantially conform to the shape of the cylindrical ends 32 of the hinge pin 28 to form a bearing surface 52 for cylindrical ends 32 and arcuate portions 37 when the door 18 moves between open and closed positions. A first boss 54 projects from a first one of the channel side walls 48 and a second boss 54 projects from the opposite channel side wall 48 across from the first boss 54. The first and second bosses 54 constrict the channel opening 46 and constitute a narrowed portion of channel opening 46. The distance between first and second bosses 54 is greater than the distance between the first and second parallel portions 36 of hinge pin 28 but less than the distance between the first and second arcuate portions 37 and the diameter of cylindrical end portions 32 of hinge pin 28. Channel 44 includes a first slot 56 at one end of channel 44 that extends into floor 14 of housing 12 and a second slot 58 across the channel 44 from first slot 56 in the radiused edge 16 of housing 12.

Referring now to Figure 2, door 18 is attached to housing 12 by aligning the first and second flattened portions 36 of hinge pin 28 with the space between the first and second bosses 54 and inserting hinge pin 28 into channel 44 until the cylindrical end portions 32 and one of the arcuate portions 37 contact bearing surface 52. The bosses 54 of receiver 30 and first and second parallel portions 36 on the hinge pin 28 are configured such that the central portion 34 of the hinge pin 28 can pass between the bosses 54 when the door 18 makes an angle of about 135 degrees with the floor 14 of the housing 12 or is opened about 45 degrees as viewed from the outside of the housing. Changes to the configuration of the bosses and/or the flattened portions 36 of the hinge pin 28 could be made to make the door 18 removable and insertable at a different angle to the housing floor. However, it is generally preferable to make the door removable in an intermediate position between the opened and closed positions so that the door will be securely retained in the receiver 30 when in the open or closed positions, the positions in which the door is usually found. With the cylindrical end portions 32 and arcuate portions 37 of hinge pin 28 in contact with bearing surface 52, door 18 can be moved from the insertion/removal position illustrated in Figure 4 to either the closed position covering opening 20, as illustrated in Figure 3, or the open position, as illustrated in Figure 5. Except when door 18 is in the intermediate position illustrated in Figure 4, it is securely retained by bosses 54 and channel 44 and cannot be removed from channel 44.

Door 18 is moved from the insertion position toward the closed position illustrated in Figure 3 by moving distal edge 27 of door 18 toward housing 12 until a first latch element 60 on door 18 engages a complementary second latch element 62 on housing 12 to hold door 18 in the first, closed position. First latch element 60 and second latch element 62 are preferably two halves of a push-push type latch that secures the door 18 to the housing 12 when first latch element 60 is pressed into second latch element 62 and that releases door 18 when door 18 is again pressed toward second latch element 62. When door 18 is pressed toward housing 12, the first latch element 60 is released from second latch element 62, and distal end 27 of door 18 can pivot away from the housing 12 toward the open position illustrated in Figure 5. Door 18 moves past the intermediate insertion/removal position illustrated in Figure 4 during this travel; however, because the forces applied against door 18 during this movement are primarily downward, door 18 does not exit receiver 30 unless a user applies an outward and upward force on door 18 when it is in the intermediate position of Figure 4. As door 18 reaches the second position, second surface 42 of arm 38 enters second slot 58 in radiused edge 16 of floor 14, and the second slot 58 forms a stop for the arm 38 and hence the door 18 and limits the opening of the door to approximately 95 degrees.

The hinge pin 28 and the receiver 30 have been described as being formed on the door 18 and housing 12, respectively. However, in another embodiment of the invention illustrated in Figure 6, the hinge pin 28 is formed on a housing 12' and the receiver 30 is formed on the door 18'. This embodiment otherwise is constructed and functions in the same manner as the embodiment described above, and the same reference numerals are used to identify elements common to both embodiments. LATCH MECHANISM

Figure 7 illustrates a fiber management shelf 1 10 comprising a housing 1 12 having a front opening 114 having a bottom edge 1 16 and a top edge 118 and a rear opening 120 having a bottom edge 122 and a top edge 124. As used herein, "housing" refers to the elements surrounding a plurality of fiber optic components and may comprise the floor of a fiber optic management shelf, the side walls of the fiber optic management shelf or a rack (not illustrated) in which the shelf is mounted, and/or a top wall that may be formed by another element mounted above the fiber optic management shelf in a rack. The housing may also be defined at least in part by one or more fiber retainer rings mounted near either side of the door at the front of a fiber management shelf. A first or front door 126 has a bottom edge 128 and a top edge 130, and bottom edge 128 of front door 126 is connected near bottom edge 116 of front opening 1 14 by a plurality of hinges 132. A second or rear door 134 has a bottom edge 136 and a top edge 138, and bottom edge 136 of rear door 134 is connected near bottom edge 122 of rear opening 120 by a plurality of hinges 140. Front door 126 includes first and second projections 142 closer to top edge 130 than to bottom edge 128 which projections are configured to be releasably retained within first and second receivers 144 near top edge 1 18 of front opening 114, and rear door 134 includes third and fourth projections 146 closer to rear door top edge 138 than to rear door bottom edge 136 which projections are configured to be releasably retained within third and fourth receivers 148 near top edge 124 of rear opening 120. As illustrated in Figure 10, first and second receivers 144 include a latch element 150 for selectively retaining first and second projections 142. Third and fourth receivers 48 include similar latch elements (not illustrated).

First projection 142 and first receiver 144 form a push-push connector or push- push fastener. As used herein, a "push-push" fastener is a fastener that selectively secures a relatively movable object, such as a door, to a relatively fixed object, such as a housing. The push-push fasteners are secured by pressing a fastener element on the moveable object against a fastener element on the fixed element, which pressing results in a connection between the fastener elements. The push-push fasteners are released by again pressing the movable object toward the fixed element, which pushing releases the fastener element on the movable object from the fastener element on the fixed element and allows the movable element to move. One such push-push fastener is disclosed in U.S. Patent No. 4,655,489 to Bisbing, and the entire contents of this patent are hereby incorporated by reference. Other push-push fasteners are known, and the present invention is not limited to a particular push-push fastener.

Figure 8 illustrates front door 126 in an open configuration, providing access to fiber termination elements 152 mounted in front opening 114. Only two fiber termination elements 152 are illustrated in Figure 8; however, in many cases, a sufficient number of fiber termination elements 152 would be provided to fill front opening 1 14. To cover front opening 1 14, front door 126 is pivoted about hinges 132 until first and second projections 142 approach first and second receivers 144 and then enter the first and second receiver 144. Continued movement of front door 126 toward housing 1 12 causes latch elements 150 in first and second receivers 144 to engage first and second projections 142 and retain the first and second projections 142 in the receivers 144 and thus hold front door 126 securely in a closed position with top edge 130 of front door 126 close to the top edge 118 of the front opening.

To open front door 26 and gain access to the fiber termination elements 152 in front opening 1 14, pressure is applied against front door 126 near top edge 130 thereof between the first and second projections 142. Front door 126 is sufficiently rigid that this pressing simultaneously moves both the first and second projections 142 further into first and second receivers 144 to release latch element 150 in the first and second receivers 144 from first and second projections 142 and allow front door 126 to pivot about hinges 132 and to the open position illustrated in Figure 9. Thus front door 126 can be opened and closed with one hand without the need to apply any pulling force on the front door 126 or on the fiber management shelf 110. Rear door 134 selectively covers rear opening 120 and splice panel 151 located therein, as illustrated in Figure 9, and is secured and released in a manner similar to that of front door 126.

Another embodiment of the present invention is illustrated in Figure 11 in which a housing 154 includes first and second spaced wall portions 156, 158 projecting from a front thereof and first and second fiber retainer rings 160 at opposite sides of the housing 154 between the first and second spaced wall portions 156, 158. Fiber retainer rings 160 are provided to help guide patch cables (not illustrated) as they exit fiber termination elements 152. Each fiber retainer ring 160 includes a receiver 162 for receiving and securing first and second projections 142 on front door 126 in the same manner as the first and second receivers 144 described above. Fiber retainer rings 160 are secured to housing 154 and thus providing receivers 162 on these fiber retainer rings 160 provides a secure connection between front door 126 and housing 154 while at the same time providing space between fiber termination elements 152 and front door 126 for the patch cables.

Another embodiment of the present invention is illustrated in Figure 12 in which a housing 170 includes lower and upper spaced wall portions 172, 174 projecting from a front thereof, and a first row 176 of fiber termination elements 152 and a second row 178 of fiber termination elements 152 mounted in housing 170. First and second fiber retainer rings 180 are provided on lower wall portion 172 for guiding patch cables leaving the fiber termination elements of the first row 176 of fiber termination elements 152, and third and fourth fiber retainer rings 182 are stacked on each of the first and second fiber retainer rings 180 for guiding patch cables of the second row 178 of fiber termination elements 152. Each of the third and fourth fiber retainer rings 182 includes a receiver 184 identical to the first and second receivers 144 of the aforementioned embodiment for receiving first and second projections 142 of front door 126 and securing front door 126 to third and fourth retainer rings 182 and thus to housing 170. STACKABLE RETAINER

Figure 13 illustrates a fiber retainer 210 comprising a split band 212 of material including a top 214, a bottom 216, a front 218 and a back 220 defining an interior passage 222 through the retainer 210. Top 214 comprises an inner surface 224, best seen in Figure 16, that is convex, and an outer surface 226 having a bail 228 near retainer back 220 and a mounting opening 230 between bail 228 and retainer front 218. Bottom 216 of retainer 210 includes an inner surface 232 that is convex, and an outer surface 234, best seen in Figure 16, that includes an L-shaped tab 236 near back 220 which L-shaped tab 236 includes a first leg 238 projecting from bottom 216 and a second leg 240 extending from first leg 238 in the direction of back 220. Bottom 216 also includes a second tab 242 having a barbed end 244. The second tab 242 is located between L-shaped tab 236 and retainer front 218. The convex inner surface 224 of top 214 and convex inner surface 232 of bottom 216, as well as convex inner portions of the retainer front 218 and retainer back 220 discussed below, form bend limiters that reduce the likelihood that an optical fiber passing through interior passage 222 will be bent beyond its minimum bend radius while passing through retainer 210.

Front 18 of retainer 210 comprises a convex inner surface 246, illustrated in Figure 14, and an outer surface 248. A first split 250 separates front 218 into a first portion 252 depending from top 214 and a second portion 254 extending from bottom 216. First portion 252 includes a bottom edge 256 having a concave end portion 258 and a mounting opening 260 holding a fastener element 262, which may comprise, for example, the receiver portion of a push-push fastener. Second portion 254 of retainer front 218 includes a top edge 264 with a convex end portion 266 that generally conforms to the shape of concave end portion 258 of front first portion 252. As can be seen in the sectional view of Figure 17, concave end portion 258 includes a cutout 268 facing the interior passage 222, and convex end portion 266 includes a cutout 270 on the side facing away from interior passage 222. Convex end portion 266 extends behind concave end portion 258 forming an overlap, and this overlap helps retain optical fibers in interior passage 222 under normal conditions while providing a smoothly sloping surface that facilitates the insertion of optical fibers into interior passage 222 when first split 250 is opened as discussed hereinafter.

Referring now to Figure 14, back 220 of retainer 210 includes a convex inner surface 272 and an outer surface 274. A second split 276 separates retainer back 220 into a first portion 278 depending from top 214 and a second portion 280 extending from bottom 216. Back first portion 278 includes a bottom edge 282, and second portion 280 has a top edge 284. Back first portion 278 includes a first connector element 286 for connecting back first portion 278 to a second connector element 288 on back second portion 280. First connector element 286 comprises a generally planar projection 290 extending away from first portion 278 which projection 290 includes a flange 292 extending from projection 290 in a direction away from interior passage 222. First and second bosses 294 are located on projection 290, one on either side of flange 292. Second connector element 288 comprises an opening 296 having a sidewall 298 with a slot 300 and first and second holes 302, one on either side of slot 300, configured to receive first and second bosses 294.

The first connector element 286 connects to second connector element 288 to attach first portion 278 of back 220 to the second portion 280 of back 220. Projection 290 of first connector element 286 is received in opening 296 of second connector element 288 and flange 292 extends into slot 300. Bosses 294 are received in holes 302 to create a snap-fit between the first connector element 286 and the second connector element 288. This connection forms a hinge 304 which hinge 304 permits first split 250 to open when the first portion 252 and second portion 254 of front 218 are pulled apart from each other. Bosses 294 and holes 302 help to maintain the connection between the first portion 278 and second portion 280 of back 220, while slot 300 allows projection 290 to move in opening 296 of second connector element 288 when the first portion 278 of the retainer back 220 bends relative to the second portion 280 of the retainer back 220.

Figures 16 and 17 illustrate a substrate 306 to which retainer 210 can be mounted as described below. Substrate 306 may comprise a portion of a fiber management shelf or a trough attached thereto (not illustrated), and the invention is not limited to mounting retainer 210 on any particular support. It is merely desirable that the support include a first mounting opening 308 and a second mounting opening 310 for accommodating the L-shaped tab 236 and second tab 242 of the bottom 216 of the retainer 210. To mount retainer 210 on substrate 306, second leg 240 of L-shaped tab 236 in inserted into first mounting opening 308 of substrate 306 until first leg 238 of the L-shaped tab 236 contacts a sidewall of the first mounting opening 308, and retainer 210 is pivoted to insert second tab 242 into second mounting opening 310 of substrate 306 until barbed end 244 of second tab 242 engages a wall adjacent to the second mounting opening 310 to secure retainer 210 to the substrate 306. A second retainer 210 can then be mounted on top 214 of the first retainer 210 by inserting the L-shaped tab 236 under the bail 228 on the retainer top 214 and pivoting the second retainer 210 until second tab 242 of the second retainer 210 enters the mounting opening 230 on top 214. Two retainers 210 stacked on top of one another without being attached to a substrate are illustrated in Figure 15.

In use, a first retainer 210 is assembled and mounted on a support such as substrate 306, and additional retainers 210 are mounted on top of the first retainer 210 as necessary for a particular application. Patch cables (not illustrated) are then inserted into the appropriate one of retainers 210 by flexing hinge 304 to create a space between first portion 252 and second portion 254 of retainer front 212 and inserting the cables into the interior passage 222. The resiliency of the material from which retainer 210 is formed causes first split 250 to reclose when the force separating the first portion 252 from the second portion 254 is removed. Fastener element 262 may be used to releasably retain a complementary fastening element (not illustrated) of a door (not illustrated) mounted adjacent to retainer 210. Preferably, the material of retainer 210 is sufficiently rigid that retainer 210 can be used as a finger pull to move the object to which it is attached while hinge 304 provides the resiliency needed to allow first split 250 to be opened and closed. The modular nature of the retainer 210 also provides design flexibility as the upper and lower portions of retainer 210 can be modified individually. For example, bottom 216 may be used to support a different top 214, a top having longer front or rear portions, for example, to change the cross section of interior passage 222. Likewise, different bottoms 216 may be provide to mount to different substrates 306, ones having a different arrangement of mounting openings. WEDGE-SHAPED RETAINER

Figure 18 illustrates a fiber retainer ring 410 according to an embodiment of the present invention which fiber ring 410 is formed form a continuous strip 411 of flexible material and includes a bottom wall 412. The bottom wall 412 has a first end 414, a second end 416, a convex top surface 418 and a bottom surface 420, and the bottom surface 420 includes first and second mounting tables 422 projecting away from the bottom wall 412. A first end portion 424 of strip 411 forms a side wall 424 that projects away from the first end 414 of the bottom wall 412. First end portion 424 includes a first or distal end 426 having a hump 428 and a second end 430 at first end 414 of bottom wall 412. Second end 416 of bottom wall 412 includes a cusp 432 which may be arcuate as illustrated or, alternately, angular (not illustrated), at which cusp bottom wall 412 turns back on itself to form top wall 434. Top wall 434 forms a ramp 436 that is inclined with respect to the bottom wall 412 and includes first end 440 at cusp 432, a ramp portion 442 having a ramp surface 445 extending from first end 440, a parallel portion 446 generally parallel to bottom wall 412 extending from ramp portion 442, and a second end portion 448 of strip 41 1 extends from parallel portion 446 toward a location on bottom wall 412 between the first end 414 and second end 416 of bottom wall 412. Second end portion 448 of strip 411 includes an end edge 450 and is generally parallel to first end portion 424 of strip 41 1 and spaced therefrom.

Figure 22 illustrates a fiber management shelf 460 that includes a trough 462 on which a plurality of fiber retainer rings 410 are mounted by inserting mounting tabs 422 into openings 464 on the trough. Fiber management shelf 460 includes an opening 466 into which modules 468 are mounted. Patch cords 470 connectable to modules 468 are inserted into fiber retainer rings 410 by pressing a portion of the patch cords 470 between the side wall 424 and second end portion 448 of the fiber retainer ring, flexing top wall 434 of the fiber retainer ring 410 toward or away from bottom wall 412 as necessary to make room for the patch cords 470 to enter the interior of the ring 410. The hump 428 at the end of side wall 424 and the curved surface between parallel portion 446 and second end 448 facilitates the insertion of the patch cords 470 into the ring, and the hump shaped end edge 450 of strip second end 448 helps to retain the patch cords in the ring 410. Once in the ring 410, the convex top surface 418 of bottom wall 412 forms a bend limiter and reduces the likelihood that a fiber optic patch cord will be bent in a manner that exceeds its bend radius when passing through the rings 410. All interior surfaces of the ring 410 may be convex like top surface 418 of bottom wall 412 to provide additional bend limiting surfaces if desired.

The conventional fiber retainer rings 906 of Figure 25 partially block the opening 905 in fiber management shelf 904 and thus generally must be removed before a module 902 is inserted or removed from the fiber management shelf. Furthermore, because of the close fit between the patch cords 900 in the modules 902 of the conventional art and the conventional retainer rings 906, the patch cords 900 themselves must generally be removed from at least the lowermost receptacles of the modules 902 before the modules 902 are inserted or removed in the shelf 904. However, as will be apparent from Figure 22, the wedge-shaped cross-section of fiber retainer rings 410 provides adequate space adjacent opening 466 in shelf 460 for a module 468 to be inserted in opening 466 without removing fiber management ring 410 or patch cords 470 from the module 468. In fact, as illustrated in Figure 23, ramp surface 445 provides a guide for sliding modules 468 into opening 466, and the ring 410 flexes as necessary about cusp 432 to allow module 468 to pass and then rebounds to its original configuration. This benefit is accomplished without significantly reducing the area of the interior of ring 410, and thus ring 410 retains the ability to hold as many patch cords as are generally needed on a shelf of the type illustrated. Modules 468 can be removed from opening 466 by sliding them along ramp surface 445 in the opposite direction from that described above. This arrangement allows modules to be inserted and removed as necessary without the need to remove patch cords from the modules or remove the fiber retainer rings from the shelf.

A method according to an embodiment of the present invention, as illustrated in Figure 24, includes a step 480 of providing a fiber retainer ring 410 on a fiber management shelf, a step 482 of aligning a fiber optic module with an opening on the shelf, a step 484 of placing the module on the ramp formed by the ring 410, a step 486 of sliding the module along the ramp and into a desired position on the shelf, and a step 488 of securing the module to the shelf.

The present invention has been described herein in terms of presently preferred embodiments. Modifications and additions to these embodiments will become clear to those of ordinary skill in the relevant art upon a reading of the foregoing description. It is intended that all such modifications and additions comprise a part of the present invention to the extent they fall within the scope of the several claims appended hereto.