Fiber Optic Connector

An optical fiber connector with a connector housing that holds a ferrule includes a retractable shutter having a shutter plate and a shutter actuator. The shutter actuator is slidably connected to the connector housing for movement relative to the connector housing between a front position and a rear position. The shutter actuator is configured to engage the mating interface as the optical fiber connector is plugged into the mating interface whereby the shutter actuator moves relative to the connector housing from the front position to the back position. The shutter plate is connected to the shutter actuator such that the shutter actuator is configured to drive the shutter plate to move between an extended position and a retracted position. In the extended position, the shutter plate is located to shield the ferrule. In the retracted position, the shutter plate is located expose the ferrule.

FIELD

This disclosure generally pertains to a fiber optic connector with a shutter.

BACKGROUND

The prevalence of the Internet has led to unprecedented growth in communication networks. Consumer demand for service and increased competition has driven network providers to continuously search for ways to improve quality of service while reducing cost. In certain applications, there is a need for passive optical interconnect components. The typical passive optical connection system comprises an optical fiber connector and a mating receptacle such as a transceiver interface or connector-to-connector adapter. The optical fiber connector is configured to be plugged into the mating interface. An optical fiber connector typically comprises a connector housing assembly and one or more ferrules terminating one or more optical fibers received in the housing assembly. Optical signals are carried through the fibers and broadcast out of the end of the ferrule. The inventors have recognized that, in some cases (e.g., when the optical signal is a laser signal that could cause injury) there is a need to provide a shutter in front of the ferrule to block the optical signals when the connector is unplugged from the mating interface.

SUMMARY

An optical fiber connector configured to plug into a mating interface comprising a ferrule having a front end portion and a rear end portion spaced apart along a longitudinal axis of the optical fiber connector. The ferrule is configured for terminating one or more optical fibers such that an optical signal carried by each of the one or more optical fibers is transmitted forward from the front end portion of the ferrule. A connector housing holds the ferrule. A retractable shutter comprises a shutter plate and a shutter actuator. The shutter actuator is slidably connected to the connector housing for movement relative to the connector housing between a front position and a rear position. The shutter actuator is configured to engage the mating interface as the optical fiber connector is plugged into the mating interface whereby the shutter actuator moves relative to the connector housing from the front position to the back position. The shutter plate is connected to the shutter actuator such that the shutter actuator is configured to drive the shutter plate to move between an extended position and a retracted position. In the extended position, the shutter plate is located to shield the ferrule. In the retracted position, the shutter plate is located expose the ferrule.

Other aspects will be in part apparent and in part pointed out hereinafter.

Corresponding parts are given corresponding reference characters throughout the drawings.

DETAILED DESCRIPTION

In the following description, terms “forward” and “rearward” are used for ease of description to indicate the direction in relation to the insertion of a connector to an adapter. For example, the forward direction indicates the insertion direction, and the rearward direction indicates the direction opposing to the insertion direction. Spatial terms, including but not limited to, “lower,” “upper,” “beneath,” “below,” “above,” and “on top,” if used herein, are utilized for ease of description to describe spatial relationships of an element(s) to another as typically depicted in the drawings. Such spatial terms encompass different orientations of the device in use or operation in addition to the particular orientations depicted in the figures and described herein.

InFIGS.1-26, an exemplary embodiment a shuttered optical fiber connector is generally indicated at reference number110. In the illustrated embodiment, as shown inFIG.1, the optical fiber connector110is in the form of an MPO-style connector and comprises an MT ferrule111. It will be apparent that the principles of this disclosure can be adapted to other optical fiber connector styles without departing from the scope of the disclosure. The ferrule111has a front end portion and a rear end portion spaced apart along a longitudinal axis LA of the optical fiber connector110(as shown inFIG.6). Ferrules in the scope of this disclosure are generally configured for terminating one or more optical fibers such that an optical signal carried by each of the one or more optical fibers is transmitted forward from the front end portion of the ferrule. In the illustrated embodiment, the MT ferrule111is configured to terminate a plurality of optical fibers. In certain embodiments, the ferrule111is configured to terminate optical fibers that carry one or more laser signals.

InFIG.2, the connector110comprises a connector housing assembly112that includes an inner connector housing114for holding the ferrule111. The connector housing assembly112also comprises an outer sleeve116surrounding the inner connector housing114.

InFIG.3, the housing assembly112comprises a pair of sleeve springs117that are provided between the outer sleeve116and the inner connector housing114to yieldably bias the outer sleeve116forward in relation to the inner connector housing114. When the connector110is mated with the mating interface201, the outer sleeve116can be pulled back in relation to the inner housing against the biasing force of the spring to unlatch the connector from the mating interface in the same manner as a conventional MPO connector is unlatched from the conventional MPO receptacle.

The inner connector housing114comprises a front body118and a back body120including a back post122. The back body120is configured to attach to the front body118to capture the ferrule111and a ferrule spring124in the inner connector housing114. In use, the back body120braces the ferrule spring124, and the front body118retains the ferrule111in the inner connector housing114such that the spring yieldably biases the ferrule111forward along the longitudinal axis LA in the conventional way.

The front body118comprises a perimeter that extends 360 degrees circumferentially about the longitudinal axis LA. The left and right side walls of the front body118(broadly, the first and second side walls) are essentially conventional MPO front body side walls comprising recesses for receiving the latch arms of an MPO-style adapter. The upper and lower end walls (broadly, the first and second end walls), by contrast, comprise unconventional features specifically for the shuttered application of the illustrated connector110. In every drawing for this disclosure except forFIG.9, one of the end walls of the inner front body118is shown in an upper position.

Referring toFIG.3, the upper wall of the inner front body118comprises a plate receiving recess130, a dovetail groove132, and a spring cradle134. The spring cradle134is located immediately in front of the conventional back flange136of the inner front body118.

Referring toFIG.5, the connector110comprises a retractable shutter140for selectively covering and uncovering the front end of the ferrule111. In the illustrated embodiment, the retractable shutter140is provided on the top of the inner connector housing114and comprises a shutter plate142, a shutter actuator144, and a shutter spring146. The shutter actuator144is connected with the shutter plate142and engages the shutter spring146. As explained more fully below, the shutter actuator144is movable relative to the inner connector housing114. The shutter plate142is connected to the shutter actuator144such that the shutter actuator144urges the shutter plate142to an extended position when the shutter actuator144is in a front position (FIGS.10and12) and the shutter actuator144urges the shutter plate142to a retracted position when the shutter actuator144is in a rear position (FIGS.11and13). In the extended position, as shown inFIGS.6-7, the shutter plate142is located in front of the ferrule111to shield the front end of the ferrule111for blocking the transmission of optical signal. In the retracted position, as shown inFIG.11, the shutter plate142is located away from the front end of ferrule111to expose the front end of ferrule111. In other words, the shutter plate142does not interfere with the optical signal path when retracted.

Referring toFIG.3, the shutter plate142is resiliently deformable and has a front portion and a rear portion spaced apart along the axis LA. In particular, the rear portion of the shutter plate142is slidably received in the plate receiving recess130, and defines first and second laterally spaced apart leg sections150separated by a gap152. Each of the leg sections150comprises an upturned foot154. The shutter plate142further comprises an upturned lip156spaced apart from the upturned feet154along the longitudinal axis LA.

Referring toFIG.9, the front body118comprises a polarity key126on the wall opposite the shutter plate142(sometimes referred to herein as the bottom wall of the front body, which is shown on top inFIG.9because the connector110is inverted). Whereas the conventional MPO polarity key is centered laterally between the side walls of the inner front body, the illustrated polarity key126is offset from lateral center. This is to distinguish the connector110from conventional MPO connectors so the connector110is not inadvertently mated with a conventional MPO receptacle. The off-center position of the key126can also be seen inFIG.7.

Referring toFIGS.10and12, in the extended position, the front portion of the shutter plate142extends downward as it extends forward away from the rear portion. This enables the front portion of the shutter plate142to shield the front end of the ferrule111to block the transmission of optical signals. Referring toFIGS.11and13, in the retracted position, the shutter plate142is resiliently deformable such that the shutter plate is configured to flatten as it moves from the extended position to the retracted position. More particularly, the shutter plate142slides in the plate receiving recess130and the front portion of the shutter plate142moves to the top of the front body118. After moving to the retracted position, when the shutter actuator144advances forward, it pushes shutter plate142forward. The shutter plate142resiliently returns to the extended position, unflattening so that the front portion of the shutter plate142extends downward to shield the front end of the ferrule111.

Referring toFIGS.14-18, the shutter actuator144comprises an actuator body160and a dovetail protrusion162below the actuator body. The dovetail protrusion162is configured to be slidably received in the dovetail groove132of the front body118and move back and forth therein. The actuator body160is connected with the shutter plate142and is captured in the longitudinal space between the upturned feet154and the upturned lip156.

InFIG.14, the actuator body160comprises a flat panel portion164and a central protrusion166protruding upward from the panel portion along the front section of the actuator body. The rear section of the panel portion164defines two spaced apart actuator legs168separated by a central gap170. Each actuator leg168comprises an upturned foot172. The upturned feet172are configured to cooperate with the front portion of the outer sleeve116to prevent the actuator body160from sliding off the connector housing assembly112.

InFIG.16, the shutter actuator144further comprises a spring holder180for holding the shutter spring146. The shutter spring146is retained between the shutter actuator144and the inner connector housing114. The shutter spring146is received in the spring cradle134on the upper wall of the front body118(as shown inFIG.11). The rear end of the shutter spring164engages the back flange136such that the shutter spring146is compressed between the shutter actuator144and the back flange136, whereby the shutter spring146yieldably biases the shutter actuator146forward toward the front position. The outer sleeve118provides clearance for the shutter actuator144and the shutter spring146.

Referring toFIG.19, the front end portion of the actuator body160is configured to engage the mating interface201as the shuttered connector110is plugged into the mating interface. In the illustrated embodiment, as shown inFIG.20, the mating interface201is an MPO-style receptacle with an inner shutter displacement wall203. As shown inFIGS.21and24, during plug-in, the front end portion of the actuator body160initially engages the shutter displacement wall203while the shutter actuator144is in the front position. With further advancement of the connector110into the receptacle201, the shutter displacement wall203prevents the shutter actuator144from moving forward and displaces the shutter actuator144rearward with respective to the inner housing body114. The shutter actuator144drives the shutter plate142rearward as shown inFIGS.22and25. As shown inFIGS.23and26, when the connector110is mated with the receptacle201, the shutter displacement wall203of the receptacle displaces the shutter actuator144to the rear position and fully retracts the shutter plate142so that the ferrule111is exposed. The shutter spring146is compressed against the flange136.

Note that inFIGS.24-26the shutter displacement wall203directly contacts the upturned lip156of the shutter plate142. For purposes of this disclosure, what is shown is considered engagement of the mating interface201with the actuator body160, or more broadly, with the shutter actuator144, because the shutter displacement wall203prevents insertion of the shutter actuator144while allowing further insertion of the connector housing114, thereby displacing the shutter actuator144rearward in relation to the connector housing.

When the connector110is removed from the receptacle201, the shutter spring146resiliently returns and pushes the shutter actuator144forward to the front position and extends the shutter plate142. The front portion of the shutter plate142resiliently rebounds to extend downward in front of the ferrule111because of the elastic memory of the shutter plate142.

Accordingly, it can be seen that the connector110provides a retractable shutter140that automatically blocks transmission of an optical signal from the ferrule111into open space when the connector110is unplugged from a mating interface201. Further, the shutter140automatically retracts to allow optical signal transmission when the connector110is plugged into the mating interface201.

Referring now toFIGS.27-41, another exemplary embodiment a shuttered optical fiber connector is generally indicated at reference number310. The optical fiber connector310is also in the form of an MPO-style connector, though the novel principles of the shutter mechanism being applied here can also be adapted to other connector formats. The illustrated optical fiber connector310comprises an MT ferrule311that has a front end portion and a rear end portion spaced apart along a longitudinal axis LA′ of the connector310. Again, the ferrule311can be configured to terminate optical fibers that carry one or more laser signals.

The connector310comprises an MPO-style connector housing assembly312that includes an inner connector housing314for holding the ferrule311so that the tip of the ferrule faces forward away from the housing assembly along a longitudinal axis LA′. The connector housing assembly312also comprises an outer sleeve316surrounding the inner connector housing314. Unlike the mating interface201for the connector110, the mating interface401for the connector310can comprise a conventional MPO receptacle that is also compatible with conventional MPO connectors. In terms of its function, the outer sleeve316performs the same function as that of the outer sleeve in a conventional MPO connector. When the connector310is mated with the mating interface401, the outer sleeve316can be pulled back in relation to the inner housing314against the biasing force of a sleeve spring317(which in this case is an integral feature of the outer sleeve) to unlatch the connector from the mating interface in the same manner as a conventional MPO connector is unlatched from the conventional MPO receptacle.

For reasons that will become apparent, the shuttered connector310comprises a remote release system for actuating the outer sleeve316by manual actuation of a remote release element at a location rearwardly spaced from the outer sleeve along the longitudinal axis LA′. In the illustrated embodiment, as shown inFIG.27, the remote release element comprises a push-pull boot390comprising a strain relief boot section391and a fastening section392for fastening the push-pull boot390to the outer sleeve316. In the illustrated embodiment, as shown inFIG.28, the fastening section392comprises opposing latch arms393configured to latch with corresponding latch recesses394on the outer sleeve316. During use, a user can grip the strain relief boot section391and pull the push-pull boot390rearward. This displaces the push-pull boot390and the outer sleeve316together in relation to the inner connector housing314. Hence, the outer sleeve316moves rearward for unlatching the connector310from a mating interface401.

In the illustrated embodiment, the outer sleeve316also comprises additional unconventional exterior features to facilitate shuttering the connector310. Particularly, the connector310comprises a plurality of exterior latch hooks395(each, broadly, a protrusion). Each exterior latch hook395comprises a rearward facing stop surface396. As will be explained in further detail below, the latch hooks395and rearward facing stop surfaces396form guide and stop features of the connector housing assembly312that aid in connecting the connector housing assembly312to the shutter mechanism.

InFIG.29, the inner connector housing314comprises a front body318and a back body320including a back post322. The connector housing assembly312further comprises a crimp ring323for securing strength elements of the cable (not shown) to the back post322in the conventional way. The back body320is configured to attach to the front body318to capture the ferrule311and a ferrule spring324in the inner connector housing314. In use, the back body320braces the rear end of the ferrule spring324, and the front body318retains the ferrule311in the inner connector housing314such that the spring yieldably biases the ferrule forward along the longitudinal axis LA′ in the conventional way.

The inner front body318comprises a perimeter that extends 360 degrees circumferentially about the longitudinal axis LA′. The inner front body318is mostly the same as a conventional inner front body of an MPO connector. However, a lower protrusion is 337 is added to the back flange336of the inner housing for providing a spring bracing structure as described in further detail below. In one or more embodiments, the spring bracing protrusion337comprises a forwardly projecting pin portion. The spring bracing protrusion337is located on the bottom end of the inner connector housing314. Those skilled would understand the spring bracing protrusion337could be provided at other position of the inner connector housing314. The polarity key326is opposite the spring bracing protrusion337on the upper end of the inner connector housing314throughout the drawings. In the illustrated embodiment, the polarity key326has the conventional position for an MPO connector.

Like the connector110, the connector310comprises a retractable shutter340for selectively covering and uncovering the front of the ferrule311. InFIG.30, the retractable shutter340is an assembly comprising a deformable shutter plate342, a shutter actuator344, and a shutter spring346. Like the shutter actuator144, the shutter actuator344is movable relative to the connector housing312between a front position (FIGS.27,30-32,40) and a back position (FIG.33). The shutter plate342is connected to the shutter actuator344such that the shutter actuator positions the shutter plate in an extended position when the shutter actuator is in the front position (FIGS.27,30-32,40) and the shutter actuator positions the shutter plate in a retracted position when the shutter actuator is in the rear position (FIG.33). In the extended position, the shutter plate342is located in front of the ferrule311for blocking the optical signals transmitted forward from the front end portion of the ferrule. In the retracted position, the shutter plate342is located relative to the ferrule to be clear of each optical signal transmitted forward from the front end portion of the ferrule.

In the illustrated embodiment, the shutter actuator344comprises an actuator housing comprising a perimeter that extends circumferentially about the longitudinal axis LA′. The actuator housing344is sized and arranged to receive the connector housing assembly312inside the actuator housing. The illustrated actuator housing344is generally rectangular, comprising opposite left and right side walls (broadly first and second side walls) and opposite upper and lower end walls (broadly, first and second end walls) The upper end wall of the actuator housing344comprises internal features configured to mount the shutter plate342on the actuator housing.

Referring toFIGS.31-37, in the illustrated embodiment, the shutter plate342comprises a rear portion and a front portion connected by a resilient living hinge371. The rear portion behind the living hinge371is broadly configured for mounting the shutter plate342to the actuator housing344. The front portion in front of the living hinge371is configured to extend downward (broadly, radially inward) from the rear portion to cover the front end of the ferrule311when extended.

Referring toFIGS.35-36, the rear portion of the shutter plate comprises a plate section373and upturned longitudinal rails375on opposite sides of the plate section. The plate section373and the upturned longitudinal rails375define a channel configured to receive an interior tongue portion376of the upper wall of the actuator housing344therein. The upturned longitudinal rails375are generally C-shaped and the interior tongue portion376has a dovetail shape such that the rear portion of the shutter plate342and the underside tongue portion of the housing344together define a dovetail joint that connects the shutter plate to the upper wall of the housing. The interior tongue portion376defines a downwardly protruding tab377, and the plate section373of the rear portion of the shutter plate342defines a latch recess378. The downwardly protruding tab377is configured to snap into the latch recess378to secure the shutter plate342to the upper wall when the rear portion is pressed onto the interior tongue portion376. Referring toFIG.37, in an alternative embodiment, the plate portion373of the rear section of the shutter plate comprises an upturned latch tab379that is configured to snap into a corresponding recess (not shown) on the underside tongue portion of the actuator housing to secure the shutter plate to the housing.

ComparingFIGS.31and32withFIG.33, it can be seen that the shutter plate342is configured to bend about the living hinge371to adjust between the extended and retracted positions. In the extended position shown inFIG.31, the front portion and the rear portion of the shutter plate342define a first interior included angle A1, and in the retracted position shown inFIG.33, the front portion and the rear portion define a second interior included angle A2greater than the first interior included angle A1. In the extended position, the front portion of the shutter plate342extends downward in front of the ferrule311to block the optical signals transmitted therefrom. The shutter plate342is configured to flatten by bending about the living hinge371as it moves from the extended position to the retracted position. More particularly, the shutter plate342flattens so that the front portion moves relative to the rear portion (which is stationary in relation to the actuator housing344) into the space between the upper portion of the connector housing assembly312and the upper wall of the actuator housing344. After moving to the retracted position, when the shutter actuator344advances forward, the shutter plate342is configured to resiliently return to the extended position, unflattening so that the front end portion extends downward to be located in front of the ferrule311.

In general, the actuator housing344is configured to be biased toward the front position (FIGS.27,30-32,40) and to engage the mating interface401as the connector310is plugged into the mating interface such that the actuator housing344slides backward along the longitudinal axis in relation to the connector housing assembly312and the ferrule311to the back position (FIG.33). The actuator housing344is sized and arranged so that the front end of the actuator housing engages an outer perimeter portion of the conventional MPO receptacle401as the connector310is plugged in. This causes the actuator housing344to be displaced rearward in relation to the remainder of the connector310as the connector housing assembly312and the ferrule311move forward into the receptacle401.

Referring toFIG.39, the lower wall of the actuator housing344comprises spring holding features382,384for holding the front section of the ferrule spring346. More particularly, the lower wall defines a pin holder382and a spring cradle384rearward of the pin holder. The pin holder382is configured to mount a spring holding pin380(broadly, a spring holder) on the actuator housing344. In the final assembled connector310, the front-most section of the shutter spring346is received over the spring holding pin380, the adjacent section of the shutter spring is received in the cradle384, and the rear end of the spring engages the spring bracing protrusion337on the back flange336. In the illustrated embodiment, the rear end portion of the spring346is received over a forwardly projecting pin portion of the protrusion337to center the spring on the protrusion. The spring346is compressed between the connector housing assembly312and the actuator housing344such that the shutter spring yieldably biases the actuator housing forward toward the front position.

In an exemplary embodiment, the actuator housing344and the connector housing assembly312comprise mutual guide and stop features configured constrain the actuator housing344to move relative to the connector housing along the longitudinal axis LA′ and to stop the shutter spring346from forcing the actuator housing forward beyond the front position. As explained above, the guide and stop features of the connector housing assembly312comprise the latch hooks395and rearward facing stop surfaces396on the outer sleeve316. Referring toFIG.38, the guide and stop features of the illustrated actuator housing344comprise longitudinal grooves386for slidably receiving each of the latch hooks395and a forward facing stop wall388at a rear end of each longitudinal groove for engaging the rearward stop surfaces396when the actuator housing is in the front position. The latch hooks395are slidably received in the grooves386and thereby constrain the actuator housing344to move relative to the connector housing assembly312only along the longitudinal axis LA′. The rearward facing stop surfaces396limit the range of motion of the actuator housing344in the forward longitudinal direction by engagement with the stop walls388when the actuator housing reaches its front position.

During use, the front end portion of the actuator housing344is configured to engage the MPO receptacle401as the shuttered connector310is plugged into the receptacle. During plug-in, the front end portion of the actuator housing344initially engages the outer perimeter of the MPO receptacle401while the shutter actuator is in the front position. With further advancement of the connector310into the receptacle401, the engagement between the receptacle401and the front end portion of the actuator housing344displaces the shutter actuator rearward and begins retracting the shutter plate342by bending the front portion upward at the living hinge371. When the connector310is mated with the receptacle401, the receptacle moves the actuator housing344to the rear position and fully retracts the shutter plate342so that it is flattened in the space between the upper portion of the connector housing assembly312and the upper wall of the actuator housing344, where it is clear of the optical signals being transmitted from the front end of the ferrule311. The shutter housing344covers the outer sleeve316of the connector310, but push-pull boot390can still be manipulated to unlatch the connector310from the MPO receptacle401. When the connector310is removed from the receptacle401, the shutter spring346resiliently returns the actuator housing344to the front position. At the living hinge371, the shutter plate342resiliently rebounds so that the front portion of the shutter plate extends downward in front of the ferrule111.

Accordingly, it can be seen that the connector310provides a retractable shutter340that automatically blocks transmission of an optical signal from the ferrule311into open space when the connector is unplugged from a mating receptacle401. Further, the connector310can be mated with a conventional MPO receptacle401, and the shutter340automatically retracts to allow optical signal transmission when the connector is plugged into the mating receptacle.

In view of the above, it will be seen that the several objects of the disclosure are achieved and other advantageous results attained.