REVERSIBLE POLARITY MPO FIBER OPTIC CONNECTOR

Abstract

A fiber-optic connector includes a connector body including a housing with a top surface and a bottom surface, the top surface and the bottom surface being joined together by two opposing side surfaces of the housing. The housing has a top slot and a bottom slot thereupon along a longitudinal axis, the top slot and the bottom slot being provided on the top surface and the bottom surface, respectively. A first key structure is slidably positioned within the top slot, and a second key structure is slidably positioned within a bottom.

Claims

1. A fiber-optic connector comprising: a connector body including a housing with a top surface and a bottom surface, the top surface and the bottom surface being joined together by two opposing side surfaces of the housing; the housing having a top slot and a bottom slot thereupon along a longitudinal axis, the top slot and the bottom slot being provided on the top surface and the bottom surface, respectively; a first key structure slidably positioned within the top slot; and a second key structure slidably positioned within a bottom; wherein the first key structure is slideable relative to the top slot on the housing and configured to remain within the top slot, wherein the second key structure is slideable relative to the bottom slot on the housing and configured to remain within the bottom slot, wherein, in operation, a polarity change of the fiber-optic connector is carried out by sliding the first key structure within the top slot toward a front end of the housing and retracting the second key structure within the bottom slot away from the front end of the housing without removal of the first key structure and the second key structure from the housing for the polarity change.

2. The fiber-optic connector of claim 1, wherein the fiber optic connector includes two or more optical fibers supported therein.

3. The fiber-optic connector of claim 2, wherein the fiber optic connector includes two optical fibers supported therein, a first of the two optical fibers carrying a transmission signal and a second of the two optical fibers carrying a receiver signal, thereby setting a polarity of the fiber-optic connector.

4. The fiber-optic connector of claim 1, wherein a portion of the first key structure and a portion of the second key structure remains attached to the housing during the polarity change.

5. The fiber-optic connector of claim 1, wherein the first key structure and the second key structure are slideable relative to the housing parallel to the longitudinal axis.

6. The fiber-optic connector of claim 1 further comprising: a locking arrangement for each of the first key structure and the second key structure.

7. The fiber-optic connector of claim 6, wherein the locking arrangement is located at the front end of the housing.

8. The fiber-optic connector of claim 1, wherein the fiber optic connector is a multi-fiber fiber optic connector.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The present invention can be best understood through the following description and accompanying drawings, wherein:

[0020] FIG. 1 is a schematic view of a typical fiber optic arrangement of fiber optic equipment and connectors;

[0021] FIGS. 2A-2D are a schematic view of fiber optic arrangements and polarity configurations;

[0022] FIG. 3 shows a prior art fixed key MPO type connector;

[0023] FIGS. 4A and 4B show a reversible polarity connector, in accordance with one embodiment;

[0024] FIG. 5 shows two reversible polarity connectors in an adapter, in accordance with one embodiment;

[0025] FIGS. 6A and 6B illustrate an exemplary fiber optic arrangement making use of reversible polarity connectors, in accordance with one embodiment;

[0026] FIG. 7 shows a reversible polarity connector with retractable guide pins, in accordance with another embodiment;

[0027] FIG. 8 shows a reversible polarity connector with retractable guide pins, in accordance with another embodiment;

[0028] FIG. 9 shows a reversible polarity connector with retractable guide pins, in accordance with another embodiment; and

[0029] FIG. 10 shows a reversible polarity connector with retractable guide pins, in accordance with another embodiment.

DETAILED DESCRIPTION

[0030] In one embodiment of the present arrangement as shown in FIGS. 4A and 4B a connector 10 is provided at the end of a multi fiber cable 12. Connector 10 has a housing 14, guide pins/guide pin openings 16 and keys 18A and 18B. The housing 14 has a passageway 22 extending between a first end and a second end. It is noted that connector 10 is shown with guide pin openings 16 (female) but all of the features of the present arrangement are equally applicable to male/pins extended connectors 10 as well.

[0031] As a basic explanation the “key” sets the order for which the fibers in connector 10 are presented to an additional opposing connector 10. A key that is ‘active’ is one that is in position to engage with an adapter. If a key is said to be reversed then it means that the key on the opposite side of the connector (that being the one that was not previously ‘active’ is now ‘active’. If connectors of both regular and reversed active keys are compared, it would be found that the fibers in connector 10 are presented to an opposing connector in opposite order. The setting of the key 18 is what sets the polarity (arrangement of fibers from cable 12) for connector 10 from the perspective of an opposing connector.

[0032] Thus, as shown in FIG. 4A, key 18A on the top of connector 10 is in a forward extended position. As shown in cut-away FIG. 4B, key 18A on the top of connector 10 is in a forward extended position with key 18B on the bottom of connector 10 in the retracted position within housing 14. Such an arrangement allows for keys 18A and 18B, on both sides of connector 10 and in respective first slot 24A and second slot 24B, to be alternately extended and retracted in order to achieve the desired polarity without disassembling the connector body. When cable 12 contains at least one of these connectors 10, keys 18A and 18B on top and bottom can be adjusted to determine whether the assembly (cable with a MPO connector on each end) is a ‘Method A’ or ‘Method B’ as referred to in the standards.

[0033] Applicants note that there are two keys 18A and 18B on connector 10 so that a fiber optic segment having two connectors 10 on either end may exhibit both A & B polarities options. When a user wants a fiber optic segment to be polarity A, the user simply sets the keys 18A on the tops of connectors 10 on both ends of the segment to the same setting, i.e. both keys 18A forward and active with both keys 18B retracted within housing 14) so that fibers exhibit the same presentation order on both sides of the fiber optic segment. To reverse to method B polarity, one of the keys such as a key 18A on one of the two connectors 10 is retracted into housing 14 and the other key 18B on that same connectors is pushed forward to active. This allows for the polarity of a single assembly or cable to be changed from A to B or B to A.

[0034] When keys 18A or 18B are retracted, nothing physically changes with fibers 12 in connector 10. Rather, the only change with connector 10 is a flipping of the order fibers 12 are presented to opposing connectors because the active or forward key 18A/18B is switched from one side of connector 10 to the opposite side.

[0035] It is noted that nothing is moving within housing 14. Fiber position number is always referenced by holding the key up and looking from left to right. By having two keys 18A/18B on opposing sides of connector 10 with the ability to activate one key or the other, this changes the definition of “up” for that connector. In other words with two movable keys 18A and 18B on connector 10 and the ability to easily change which key is active (used to determine which way is “up”) a user can reverse the order of the fibers presentation on a connector 10 on one end of an assembly only, switching the segment from a Method A to a Method B or vice-versa.

[0036] Moreover, in the cut away example FIG. 4b, connector 10 shows top key 18A activated (extended out) and bottom key 18B retracted back into connector 10. As is evident from FIGS. 4A and 4B, keys 18A and 18B can be used to change the polarity of connector 10 without the need for opening any part of connector 10, such as housing 14, unlike the prior art configurations.

[0037] As shown in FIG. 5, which shows two connectors 10 fitted into an adapter 20. Such keys 18A (only top keys 18A are visible in FIG. 5) can be operated by simply sliding key 18A forward and backward, or by pressing the key below the surface of the housing and locking arrangement, located towards the front of housing 14 of connector 10. Each key 18A and 18B can thus be operated independently with non-specialized tools and without disassembly of the connector, as the tab for keys 18 is accessible through a top opening 26 in at least part of the housing 14. It is noted that in FIG. 5, such a tab for adjusting keys 18, during a connection to another connector 10 via adapter 20, would actually fit within adapter 20. The other slide mechanism shown in FIG. 5 is related to another feature regarding an adjustable guide pin arrangement discussed in more detail below.

[0038] One exemplary arrangement for demonstrating the usefulness of connectors 10 is shown in FIGS. 6A and 6B. In FIG. 6A a first equipment #1 is shown connected to a second equipment #2 using five spans of fiber with MPO type connectors on such spans at four locations (#1-#4). That is, at each location #1-#4, there is an adapter 20 and two opposing MPO connectors, one for each segment on either side of the adapter. The connectors at points #1 through #3 each maintain the same polarity from the prior segment (Method A polarity), and at connector #4 the polarity reverses (Method B polarity) before entering equipment 2 as shown in the figure.

[0039] Turning now to FIG. 6B, assuming that owing to some required connection change, equipment #1 now needs to be connected to equipment #3 at a different location instead of equipment #2. As a result the third segment of fibers after location #2 and their connector facing segment 2 on the opposing side of location #2 now needs to be reversed in polarity (Method B) whereas in the prior FIG. 6A arrangement (connected to equipment #2) that same connector/segment would have simply retained the same polarity (Method A). As a practical matter, in the prior art, an installer or user would have had to replace the fiber segment 3 with a new patch fiber segment having a different (opposite) pre-terminated fixed polarity connector to fit into the adapter at location #2 in order to change the polarity of the connection now entering into equipment 3. Or, using prior art connectors that could change polarity, the user would have to open the housing of the connector on the third fiber segment after location #2 and change the polarity, possibly damaging/diminishing that connector and the fiber connections therein.

[0040] However using the present arrangement, assuming the connector for fiber segment three exiting location #2 was a connector 10 according to the present arrangement, connector 10 could simply be removed from the adapter 20 at location #2 have the appropriate key 18 retracted/moved forward, and reinserted into the adapter as shown in FIG. 6B, changed from Method A to Method B polarity.

[0041] In another embodiment of the present invention as shown in the following FIGS. 7-10, in addition to connector 10 being a reversible polarity connector 10 using keys 18A and 18B as explained above, such connectors 10 may also have a retractable guide pin arrangement 50 so that connector 10, in addition to having reversible polarity also can exchange between male (extended) and female (retracted) guide pin configurations.

[0042] As shown in FIG. 7, connector 10 has a guide pin arrangement 50 shown in the extended male configuration. Guide pin arrangement 50 includes an attached retraction tabs 52 (one opposing side not shown) located on either side of the connector. In FIG. 8 connector 10 has the same retractable guide pin arrangement 50 shown in the extended male configuration. In the embodiment shown in FIG. 8, guide pin arrangement 50 includes attached retraction tabs 52B located on the top of connector 10.

[0043] In FIG. 9 connector 10 again has the same retractable guide pin arrangement 50. In the embodiment shown in FIG. 9, guide pin arrangement 50 includes a single attached retraction tab 52C located on the top of connector 10 in between a bifurcated arrangement of tab(s) 18C to change the polarity of key 18A. In FIG. 10 connector 10 has the same retractable guide pin arrangement 50. In the embodiment shown in FIG. 10, guide pin arrangement 50 are spring biased via biasing springs 51 (internal) and held in position using pin locks 54 on top of connector 10.

[0044] As an example of how the embodiment with retractable pins 50 supplements the usefulness of the reversible polarity of connector 10 using keys 18, Applicants note that standard equipment typically has pins in it, but some of the components in given channel (e.g. a 4 connector channel of patch cord, trunk, patch cord, trunk, patch cord etc.... ) will have pins and the rest will not since it is always required to mate a male to a female. So if a user were to add or subtract fiber segments/elements from the channel, even if the polarity can be changed, they may or may not end up with connectors with pin arrangements that can be mated together. By adding switchable guide pins this possible drawback can be overcome.

[0045] While only certain features of the invention have been illustrated and described herein, many modifications, substitutions, changes or equivalents will now occur to those skilled in the art. It is therefore, to be understood that this application is intended to cover all such modifications and changes that fall within the true spirit of the invention.