Cross connect system and tray

A fiber optic cross connect system comprising a case defining a tray receiving space and at least one tray slideable in and out of the space between a first closed position, a second intermediate position and a third open or accessible position and a sliding engagment between a sidewall of the case and a side edge of the tray is disclosed. The sliding engagment comprises an elongate link member which is stationary as the tray is moved between the first closed position and the second intermediate position and moves with the tray as the tray is moved between the second intermediate and the third open position and such that the elongate link member does not interfere with fiber optic cables which are interconnecting external devices with devices on the tray. In a particular embodiment the link member is held stationary by a releasable locking mechanism.

FIELD OF THE INVENTION

The present invention relates to a cross connect system and tray. In particular, the present application relates a cross connect system comprising a plurality of slideable trays and a sliding engagement between a case housing the trays and each tray.

BACKGROUND OF THE INVENTION

Optical cross connects are used in industries such as telecommunications to switch high-speed optical signals in a fiber optic network. Typically, fiber optic cassettes or splice boxes for such uses are removeably arranged on tray systems within a rack mounted case. In order to remove the trays from the racks for operational or maintenance purposes, rail systems are provided to allow the trays to slide out, allowing users to perform work on the cassettes or splice boxes. One drawback of current systems is that the trays cannot be fully extended out of the rack due to cable length and bend radius constraints. While partial extension provides access to the connectors at the fronts of the cassettes or splice boxes, full extension would provide easy access to the rear of the cassettes or splice boxes.

SUMMARY OF THE INVENTION

In order to address the above and other drawbacks there is provided a fiber optic system for connection to at least one external device. The system comprises a case comprising two opposed side walls defining a tray receiving space therebetween, a tray slideably received within the tray receiving space for receiving at least one device comprising a fiber optic cable exiting a rearward side of the device and for interconnecting the at least one device to the at least one external device, the tray comprising a vertical side edge and a cable guide channel comprising an exit in the vertical side edge and defining a cable receiving passage between the exit and the rearward side of the at least one device, the cable guide channel receiving the fiber optic cable for guiding at least a portion of the cable between the rearward side of the at least one device and the at least one external device via the exit, and a sliding engagement between the vertical side edge and an adjacent one of the sidewalls comprising an elongate link member comprising a first side and a second side opposite the first side, the first side mounted to the adjacent one of the sidewalls for sliding along the sidewall and the vertical side edge mounted to the second side for sliding along the second side. The tray is moveable between a closed tray position wherein the tray is received within the tray receiving space and an open tray position wherein the tray is in front of the tray receiving space via an intermediate position where the tray is partly in front of the tray receiving space and further wherein the elongate link member is stationary as the tray is moved between the closed position and the intermediate position and the elongate link member moves with the tray as the tray is moved between the intermediate position and the open position.

There is also provided a cross connect cassette system. The system comprises a case comprising two opposed side walls defining a tray receiving space therebetween, a tray slideably received within the tray receiving space for receiving a plurality of fiber optic cassettes side by side, the tray slideable between a first tray position wherein the tray is within the tray receiving space, a second tray position wherein the tray is extended partially in front of the tray receiving space and a third tray position wherein the tray is in front of the tray receiving space, and a sliding engagement between each side wall and an adjacent side edge of the tray, at least one first sliding engagement comprising an elongate link member comprising a first side mounted to the side wall for sliding along the sidewall between a stationary position and an extended position and a second side, the side edge mounted to the second side for sliding along the second side between a rearward position and a forward position, a first locking mechanism for securing the elongate link member to the sidewall in the stationary position and a second locking mechanism for securing the elongate link member to the side edge in the forward position. By moving the tray away from the first tray position towards the third tray position via the second tray position the side edge is moved away from the rearward position into the forward position disengaging the first locking mechanism and releasing the elongate link member from the retracted position and engaging the second locking mechanism and securing the elongate link member to the side edge in the forward position and for movement therewith and wherein by moving the tray away from the third tray position towards the first tray position via the second tray position the elongate link member is moved away from the extended position into the stationary position and the side edge is moved away from the forward position towards the rearward position engaging the first locking mechanism and securing the elongate link member in the stationary position while disengaging the second locking mechanism and releasing the side edge from the forward position for sliding along the second side.

Additionally, there is provided a slider comprising an elongate link member, a first elongate rail slideably mounted to the elongate link member for movement between a first position and a second position, a second elongate rail slideably mounted to the elongate link member for movement between a third position and a fourth position, and a first locking mechanism for releasably securing the a first elongate rail to the elongate link member in the first position and a second mechanism locking for releasably securing the second elongate rail to the elongate link member in the third position. Movement of the second elongate rail into the third position disengages the first locking mechanism thereby releasing the first elongate rail from the first position and the elongate link member for movement towards the second position and engages the second locking mechanism thereby releasably securing the second elongate rail in the third position to the elongate link member and wherein movement of the first elongate rail into the first position disengages the second locking mechanism thereby releasing the second elongate rail from the third position and the elongate link member for movement towards the fourth position and engages the first locking mechanism thereby releasably securing the first elongate rail in the first position to the elongate link member.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

Referring now toFIG. 1, a cross connect system, generally referred to using the reference numeral10, will now be described. The system10comprises at least one slideable tray12illustratively mounted within a case14. The case14comprises a top cover16, a bottom wall18and a pair of opposed sidewalls20defining a tray receiving space22therebetween. The case14is illustratively mountable to the rails of a rack (not shown) via a pair of mounting brackets24wherein one of the brackets24is attached to an outer surface of a respective one of the sidewalls20. The front edges of the top cover16and walls18,20define an opening via which the tray receiving space22can be accessed. In an embodiment, top cover16is removably attachable to the case14via fasteners26. Illustratively, each tray12is slideably positionable between a first closed tray position (A) where the tray12is within the tray receiving space22, a second intermediate tray position (B) where a portion of the tray12is in front of the tray receiving space22and a third open tray position (C) where the tray12is positioned in front of the tray receiving space22and accessible, as will be discussed in further detail below.

Referring now toFIGS. 2A and 2Bin addition toFIG. 1, each tray12receives a plurality of devices28such as removable fiber optic modules or cassettes illustratively arranged side by side on an upper surface30thereof. In an embodiment, each fiber optic device28is secured to the tray12using a fastener comprising tabs (not shown) of inverted “T” cross section which engage with respective slots32machined or otherwise formed in the tray12. Each device28typically comprises a plurality of receptacle modules (not shown) arranged in a row along a forward edge of the device28. Each cassette also terminates a fiber optic cable34, such as a trunk cable or the like, comprising a plurality of optic fibers at a rearward edge of the device28. Cables34exiting the rear of device28for connection to external devices (not shown) are directed to a cable guiding channel36on illustratively the left side of the tray12, where the cables34exit the tray and are directed towards cable supports38mounted to the outside of a sidewall20.

Still referring now toFIGS. 2A and 2B, as discussed above the devices28are illustratively fiber optic cassettes comprising a plurality of optic fibres (not shown) interconnecting each optic fiber of the fiber optic cable34with a respective one of a plurality of receptacles (not shown) arrange along a front face of each of the fiber optic cassettes. The receptacles are illustratively configured for receiving a complementary plug of one of a plurality of optic fibers (both not shown) in a cross connect configuration. The plurality of optic fibers enter the tray via a passageway39positioned at a side of the tray12.

Referring now toFIG. 3, a side edge of each tray12is mounted to a respective sidewall20of the case14via a pair of sliding engagements, or sliders40. At least one of the sliders40comprises a first elongate rail42attached to a sidewall20, a second elongate rail44attached to a side of the tray12, and an elongate link member46arranged in parallel to and slideably interconnecting the first elongate rail42and the second elongate rail44. The sliders40allow the tray12to slide in and out of tray receiving space22between the first closed tray position wherein the tray12is fully recessed inside tray receiving space22, the second intermediate tray position wherein the tray12is partially outside of tray receiving space22, and the third open tray position wherein the tray is fully outside of tray receiving space22.

Referring now toFIG. 4in addition toFIG. 3, an elongate link member46comprising a T-shaped flexible latch48that is held inside a latch slot50in a respective sidewall20is provided. In the first tray position the ends52of the latch48are each engaged by a respective one of a pair of wedge shaped features54which are illustratively moulded into the sidewall20to form a first locking mechanism, securing the elongate link member46in place while the tray12is free to slide between first tray position and second tray position. As a result, between the first tray position and the second tray position, both the first elongate rail42and the elongate link member46are stationary, while the second elongate rail44is slideable along the elongate link member46.

Referring now toFIG. 5A, as the tray12is slid to the second tray position B, a second locking mechanism comprising a pair of opposed flexible tabs56on the elongate link member46are engaged by the forward edge58of the second elongate rail44and such that they are deflected towards one another and slide along an inner surface of the second elongate rail44. In this manner the second elongate rail44and elongate link member46are engaged with an increased friction but still able to slide respective to one another.

Referring toFIG. 5B, as the second elongate rail44continues to be slid vis-à-vis the elongate link member46, an abutment60on the left edge of the tray12engages the flexible latch48. The flexible latch48flexes out of the path of the abutment60against the bias of the flexible stem62and such the ends52of the latch48clear the wedge shaped features54releases the elongate link member46from the latch slot50, thereby allowing the elongate link member46to slide relative to the sidewall20from the second tray position to the third tray position. Conversely, as the tray12is slid from the third tray position to the second tray position, the ends52of the T-shaped latch48slide up the angled outer surfaces64of the wedge shaped features54against the bias of the flexible stem58until the wedge shaped features54are cleared and the ends52of the T-shaped latch48are returned into the latch slot50.

Referring now toFIGS. 6A and 6B, once the tray12is slid to the third tray position, a tab66engages a stop68preventing the tray12from sliding any further away from the tray receiving space22. With the tray12in the third tray position, both the front and the rear of the cassettes28are easily accessible for operational and maintenance purposes.

As a person of ordinary skill in the art will now understand, the steps of sliding the tray12out of the tray receiving space22may be repeated in reverse to slide the tray12back into the tray receiving space22. Between the third tray position and the second tray position, the second elongate rail44and the elongate linking member46slide together as the tray12enters the tray receiving space22. As discussed above, as the tray12reaches the second tray position, the abutment60on the side of the tray12releases the latching mechanism48and the latching mechanism48re-enters the latch slot50, thus fixing the elongate link member46in place and allowing the second elongate rail44to slide along the elongate link member46as the tray further slides in tray receiving space22towards the first tray position A.

Referring back toFIGS. 2A and 2Bin addition toFIG. 6B, the sliding mechanism40ensures that each tray12exits the tray receiving space22sufficiently before the elongate link member46is released from the first elongate rail42and may begin to slide along with the tray12. Additionally, sliding mechanism40ensures that elongate link member46completely enters the tray receiving space22before it reengages with the first elongate rail42and allows the tray12to slide into the tray receiving space22along elongate link member46. This mechanism ensures that during movement of the tray12the fiber optic cables34, which are received in the guiding channel36and directed towards the cable supports38, do not engage the sidewall20or elongate link member46, which could otherwise damage or foul the movement of the fiber optic cables34. In addition, sliding mechanism40ensures that the fiber optic cables34maintain a substantially constant bend radius when wrapping around the corner of the case14while minimizing the required length of the fiber optic cables34.

Referring now toFIGS. 7A to 7Cin addition toFIG. 1, in order to retain the tray12in a fourth tray position D, an actuatable lock is provided. The lock engages pair of angled walls72and a recess74to retain tray12in the fourth tray position whereby cassettes28are easily accessible, for example for patching purposes. The actuatable lock comprises a plunger assembly76comprising a plunger78retained in a plunger housing80. The plunger78is biased away from the housing80by a spring (not shown). The plunger assembly76is moveable away from the sidewall20by a release mechanism comprising a slide82which extends from a finger actuator84positioned towards the front of the tray12to the plunger assembly76. The plunger assembly76is held such that it may move only laterally relative to the tray12but comprises bevelled walls86which interact with bosses (not shown) on the release mechanism82. As the slide82is pulled forward, the bosses impart a lateral force on the plunger mechanism76via the bevelled walls86and such that the plunger mechanism76is moved away from the sidewall20and disengaged from the recess74.

Still referring toFIGS. 7A to 7C, when the tray12is slid into the fourth tray position from either direction, the plunger78engages one of the angled walls72and retracts into the plunger housing80against the bias of the spring. Once the angled wall72is cleared, the plunger78is biased by the spring into the recess74, locking the tray12into the fourth tray position. To unlock the tray12from the fourth tray position D and allow it to once again freely slide in and out of the tray receiving space22, the finger actuator84is pulled, causing the slide82to move forward and the plunger assembly76to move laterally, freeing the plunger78from the recess74.

Still referring toFIGS. 7A to 7Cin addition toFIG. 1, each elongate link member46further comprises a retention means for holding the tray12in the first tray position whereby the tray12is within the tray receiving space22. In an embodiment, the retention means comprises an angled protrusion88requiring the tray12to be pulled with enough force to cause the plunger78to compress the spring and retreat into the housing80. As the protrusion88is angled on both of its sides, the same amount of force is required to pull the tray12out of the first tray position or to push the tray12into the first tray position.

Referring now toFIGS. 8A and 8B, in an alternative embodiment, the first locking mechanism comprises a push latch assembly90mounted for movement within an aperture92in the elongate link member46. The push latch assembly90comprises a first latch part94comprising a pair of flexible fingers96each comprising a hooked end98which are inserted into a second latch part100. The pair of flexible fingers96engage respective ones of a pair of opposed cutaways102in the second latch part100thereby securing the first latch part94to the second latch part100. Prior to assembly a spring104is placed about second latch part100and such that, when the push latch assembly90is assembled, the spring104biases the assembly. The second latch part100further comprises a T-shaped end106which is held within the latch slot50. In the first tray position the tips108of the latch T-shaped end106are each engaged by a respective one of the pair of wedge shaped features54.

Still referring toFIGS. 8A and 8B, as will know be understood by a person of ordinary skill in the art, as the tray12is moved into the second tray position B from the first tray position A, the abutment (reference60inFIG. 5A) engages the button-like end110of the first latch part94. This forces the push latch assembly90to move laterally against the bias of the spring104and the tips108of the T-shaped end106out of the latch slot50. The elongate link member46is then released such that it can travel together with the tray12. As the tray12is moved into the second tray position B from the third tray position C, the tips108of the T-shaped end106travel along the angled outer surfaces64against the bias of the spring104and once clearing the wedge shaped features54are moved into the latch slot50under bias of the spring104.

While system10has herein been described as comprising trays12with a slider mechanism40on their left side and locking means58on their right side, it is to be understood that a mirrored configuration may also be implemented. In an embodiment, mirrored systems10may be used side by side to maximize spatial efficiency.

Although the present invention has been described hereinabove by way of specific embodiments thereof, it can be modified, without departing from the spirit and nature of the subject invention as defined in the appended claims.