Fiber-optic endface cleaning apparatus and method

A cleaning apparatus (1100) for cleaning an endface (1104) of an optical fiber (1106), wherein a portion of the optical fiber is contained within an interface device (1103) is provided. The cleaning apparatus includes a housing (1114) having an interface portion (1124) adapted to be received by the interface device. The cleaning apparatus further includes a fluid dispensing assembly (1116) at least partially disposed within the housing, wherein at least a portion (1112) of the fluid dispensing assembly engages the endface when the interface portion is received by the interface device. The fluid dispensing assembly is operable to deliver a fluid and a solvent upon the endface when the interface portion of the housing is received by the interface device to aid in the removal of contaminants on the endface. The cleaning apparatus may include a contact cleaning assembly (1304) and/or a microscope (1408).

FIELD OF THE INVENTION

The present invention relates generally to fiber-optic cleaning systems and, more specifically, to cleaning systems for cleaning fiber-optic endfaces.

BACKGROUND OF THE INVENTION

The proliferation of fiber-optic communications has led to its widespread implementation and use in industry, especially in the fields of telecommunications and data communications. It is well known in the industry that fiber-optic endfaces must be kept clean and undamaged within fiber-optic communication systems. A fiber-optic endface is the cross-sectional surface that is created when an optical fiber is cut for termination. The fiber-optic endfaces are typically supported by a connector that couples to a bulkhead adapter (also sometimes referred to as a backplane adapter or a mating adapter) having an alignment sleeve for receiving the fiber-optic endface.

Failure to keep an endface clean and undamaged results in signal loss because of scattering effects at the endface of the optical fiber. As bandwidths increase, particularly with the rise of wavelength division multiplexing (WDM) technology, the need for cleanliness at the fiber-optic endface is even more important. Further, since fiber-optic communication systems handle heavy bandwidth traffic, the cleanliness at the fiber-optic endface is particularly important because the laser power driving the fiber-optic communication signals is typically higher. When a high-powered laser strikes a small piece of debris on the fiber-optic endface, the debris burns, leaving a film of soot on the fiber-optic endface that degrades communication signals. As a result, the “dirty” fiber-optic endface at the interconnect point must be taken out of service and repaired.

While cleanliness of the fibers is of utmost importance, access to the fiber endface is often very limited. Most fiber-optic interconnects are arranged in a male-to-male configuration and utilize a female-to-female configured alignment sleeve for coupling. Thus, when the user-side connector is removed, one endface is readily accessible, while the other resides at the bottom of a deep narrow hole. This makes cleaning very difficult. Further, backplane fiber-optic interconnects are notoriously difficult to access for maintenance, cleaning, and repair. Whether multi-fiber or single-fiber (simplex), these fiber-optic connectors are typically located near the back of a narrow “card slot.” A typical slot is 1.5 inches wide and 12 inches deep, and rather difficult to access for service. Most current cleaning techniques require the user to disassemble the backplane to gain access to the connector for cleaning.

To overcome the access problem, some cleaning system manufacturers have designed cleaning systems that are insertable within the alignment sleeve for cleaning the fiber-optic endfaces without necessitating the removal of the connector from the bulkhead adapter. However, the methods used by these systems are disadvantageous for several reasons. For instance, most of these methods utilize contact cleaning methods, wherein the endface is directly contacted by a non-fluid material, such as a cotton swab or a physical structure coated with an adhesive. Because the fiber-optic endface is directly contacted by a non-fluid material, these systems contain the inherent risk of adding contamination to the fiber-optic endface as a portion of the non-fluid contact material may remain on the fiber-optic endface. Further, the physical contact may result in the introduction of defects upon the fiber-optic endface, such as scratches on the fiber-optic endface through “dragging” of a contaminate particle across the endface. Thus, it is widely understood that contact cleaning methods are one cause of endface scratching, which often results in signal degradation.

Other cleaning manufacturers have designed cleaning systems that involve injecting a liquid within the bulkhead adapter for cleaning the fiber-optic endfaces without necessitating the removal of the connector from the backplane. However, current methods of this nature are also disadvantageous for several reasons. For instance, a typical bulkhead adapter is not watertight, therefore significant quantities of the liquid, such as water, are leaked from the bulkhead adapter, thereby presenting a potential or a perceived potential for damage to the expensive communication equipment located in proximity to the connector. Further, these systems do not provide an immediate evacuation system for the rapid removal of the liquid injected within the bulkhead adapter, thus increasing the potential for damage to the surrounding communications equipment and increasing the potential for residuals of the fluid to remain on the endface, thus contaminating the endface.

Moreover, it has been found that during cleaning operations, cleaning solvents may collect in a chamfer formed in the fiber-optic endface. The chamfer is located around the periphery of the fiber-optic endface. The chamfer acts as a protected cavity, which ultimately forms a reservoir, that retains solvent within the alignment sleeve. Thus, after the cleaning process is complete, the cleaning solvent and any contaminants contained in the chamfer often flow back onto the fiber-optic endface, recontaminating the endface.

Further, existing assemblies do not incorporate an inspection microscope within the endface cleaning apparatus or a means to receive one. Thus, the cycle time to clean and inspect a fiber-optic endface is increased since the operator is forced to swap between the endface cleaning apparatus and an inspection microscope. Further still, the potential for the introduction of contaminants or damage to the fiber endface due to the repetitive coupling and decoupling of the endface cleaning apparatus and inspection microscope during the cleaning process is also substantially increased. In other aspects, a manufacturer must design/develop separate tooling to produce and inventory two separate units, a endface cleaning apparatus and a microscope, resulting in increased costs relative to a combined unit.

Further still, existing assemblies do not incorporate a contact cleaning assembly with a non-contact cleaning assembly, such that if the non-contact cleaning process is not completely effective, the aggressiveness of the cleaning operation can be increased by incorporating contact cleaning methods into the cleaning process.

Therefore, a need exists for a endface cleaning apparatus that is effective in cleaning fiber-optic endfaces while exhibiting a reduced potential of contamination introduction and/or damage to the fiber-optic endface being cleaned and does not expose nearby components to rogue fluids. Further, there exists a need for a endface cleaning apparatus that is operable to receive or contains a microscope therewithin to reduce the cleaning process cycle time and risk of fiber-optic endface contamination.

SUMMARY OF THE INVENTION

One embodiment of a cleaning apparatus formed in accordance with the present invention is provided. The cleaning apparatus is operable for use in cleaning an endface of an optical fiber, wherein a portion of the optical fiber is contained within an interface device. The cleaning apparatus includes a housing and a fluid dispensing assembly at least partially disposed within the housing. The fluid dispensing assembly includes an interface portion adapted to be received by the interface device and engage the endface. The fluid dispensing assembly is operable to deliver a fluid and a solvent upon the endface to aid in removal of contaminants on the endface.

A first alternate embodiment of a cleaning apparatus formed in accordance with the present invention is provided. The cleaning apparatus is operable for use in cleaning an endface of an optical fiber. The cleaning apparatus includes a housing and a first attachment device coupled to the housing. The first attachment device is adapted to permit the selective coupling of a container of fluid to the housing. The cleaning apparatus also includes a second attachment device coupled to the housing, the second attachment device adapted to permit the selective coupling of a container of solvent to the housing. The cleaning apparatus also includes a fluid dispensing assembly at least partially disposed within the housing and in fluid communication with each of the containers, the fluid dispensing assembly operable to deliver the fluid and the solvent from each of the containers upon the endface to aid in the removal of contaminants on the endface.

A second alternate embodiment of a cleaning apparatus formed in accordance with the present invention is provided. The cleaning apparatus is operable for use in cleaning an endface of an optical fiber. The cleaning apparatus includes a housing and a fluid dispensing assembly coupled to the housing and operable to deliver a fluid and a solvent upon the endface to aid in the removal of contaminants on the endface. The cleaning apparatus further includes a contact cleaning assembly coupled to the housing, the contact cleaning assembly having an engagement member operable to engage the endface and dislodge contaminants on the endface through physical contact.

A third alternate embodiment of a cleaning apparatus formed in accordance with the present invention is provided. The cleaning apparatus is operable for use in cleaning an endface of an optical fiber, wherein a portion of the optical fiber is contained within an interface device. The cleaning apparatus includes a contact cleaning assembly, wherein the contact cleaning assembly includes an interface portion configured to be at least partially received within an interface device. The contact cleaning assembly further includes an engagement member coupled to the interface portion and adapted to engage the endface and remove contaminates on the endface through physical contact. The cleaning apparatus further includes a drive mechanism coupled to the contact cleaning assembly, the drive mechanism adapted to move the engagement member upon the endface.

A fourth alternate embodiment of a cleaning apparatus formed in accordance with the present invention is provided. The cleaning apparatus is operable for use in cleaning a first endface of a first optical fiber and a second endface of a second optical fiber, wherein a portion of each of the first and second optical fibers are contained within an interface device. The cleaning apparatus includes a housing and a fluid dispensing assembly at least partially disposed within the housing. The fluid dispensing assembly includes a first interface portion and a second interface portion, the first and second interface portions adapted to be received by the interface device. The fluid dispensing assembly is operable to deliver a fluid and a solvent via the first and second interface portions upon the first and second endfaces to aid in the removal of contaminants on the first and second endfaces.

One embodiment of a method formed in accordance with the present invention for cleaning an endface of an optical fiber contained within an interface device is provided. The method includes the step of inserting an interface portion of a cleaning apparatus within the interface device so as to position a nozzle in proximity to the endface. The method further includes the steps of intermixing a solvent with the fluid; and dislodging contaminates from the endface through contacting the endface with an engagement member.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is a fiber-optic endface cleaning apparatus for cleaning the endface of an optical fiber. While not limited to the following application, the endface cleaning apparatus of the present invention is particularly suitable for cleaning an endface of an optical fiber contained in an interface device, which is defined as any assembly, device, or apparatus having an exposed fiber-optic endface therein or supported thereby. Examples of such an interface device include any one or more, or combination of the following: an alignment sleeve, bulkhead adapter, transceiver, transmitter, detector, or connector. A bulkhead adapter is also sometimes referred to as a “mating adapter” or a “backplane adapter,” and their design and configurations vary greatly. For illustrative purposes only, the embodiments of the present invention will be described either in relation to a fiber-optic connector contained within a bulkhead adapter, or alternately, in relation to a fiber-optic connector that has been removed from the bulkhead adapter. However, it should be apparent to one skilled in the art that the fiber-optic endface cleaning apparatus may be used in any situation where an exposed fiber-optic endface is present.

In general, and as will be further described below, the fiber-optic endface cleaning apparatus includes a system for applying a pressurized fluid and a cleaning solvent upon a fiber-optic endface. In other embodiments of the present invention, the fiber-optic endface cleaning apparatus is operable to receive or includes a microscope for illuminating and viewing the endfaces of optical fibers. In still yet another embodiment of the present invention, the fiber-optic endface cleaning apparatus includes a retractable baffle for aiding in the removal of fluids from the fiber-optic endface. In additional embodiments, the fiber-optic endface cleaning apparatus includes a contact cleaning assembly, the contact cleaning assembly having an engagement member adapted to contact and dislodge contaminates from the endface through physical contact. In further embodiments, the endface cleaning apparatus is adapted to removably couple to a container of pressurized fluid and a container of solvent.

FIGS. 1 and 2illustrate one embodiment of a fiber-optic endface cleaning apparatus100formed in accordance with the present invention. The fiber-optic endface cleaning apparatus100is capable of interfacing with a fiber-optic bulkhead adapter200, such as those typically used in well known fiber-optics data transmission systems, to clean the endfaces of the optical fibers contained therein. The fiber-optic endface cleaning apparatus100includes a housing110, an evacuation system104, a cleaning solvent delivery system106, and a pressurized fluid delivery system108.

Inasmuch as the fiber-optic endface cleaning apparatus100will be better understood in light of a description of the fiber-optic bulkhead adapter200that the endface cleaning apparatus100interfaces with, a detailed description of the fiber-optic bulkhead adapter200will precede a discussion of the fiber-optic endface cleaning apparatus100. The illustrated fiber-optic bulkhead adapter200is suitable for use in most well-known fiber-optics data transmission systems. The fiber-optic bulkhead adapter200typically includes a first pair of female inputs204and206located on a first end of the bulkhead adapter200. The female inputs204and206are aligned with a second pair of female inputs (not shown) facing in an opposite direction relative to the first pair of female inputs204and206on a second end of the bulkhead adapter200. The female inputs204and206are sized and configured to receive fiber-optic connectors, such as those referenced by numerals214and216therewithin. When fiber-optic connectors are received within aligned, opposing female inputs, the optical fibers217(one shown) contained within the opposing fiber-optic connectors are received within an alignment sleeve219housed within the bulkhead adapter200. With the connectors received as described, the endfaces of the opposing fiber-optic connectors face one another within the alignment sleeve219to permit the passage of optical signals between the optical fibers, as is well known in the art.

In a typical application, the bulkhead adapter200is mounted through a bulkhead (not shown) to allow the connection of the optical fibers through the bulkhead. Therefore, while the fiber-optic connectors received within female inputs204and206may be easily accessed and removed by a user, access to the fiber-optic connectors214and216is typically blocked by the bulkhead. For instance, the bulkhead adapter200may allow passage of the optical fibers through the bulkhead of an amplification unit, wherein to “unplug” the fiber-optic connectors214and216from the bulkhead adapter200, one would need to disassemble the amplification unit to access the fiber-optic connectors214and216, a process that is labor intensive and associated with a high potential for equipment damage.

Once the fiber-optic connectors214and216are inserted into the bulkhead adapter200, the fiber-optic endfaces202associated with each connector are exposed to the other side of the bulkhead and are ready to interface with another fiber-optic connector. In practice, once a fiber-optic connector is removed from one of the female inputs204or206, the fiber-optic endface cleaning apparatus100of the present invention may be inserted into the empty female input204or206. The fiber-optic endface cleaning apparatus100may then be used for cleaning the endfaces202of each fiber-optic strand217terminated within the fiber-optic bulkhead adapter200.

Still referring toFIGS. 1 and 2and focusing on the structure of the bulkhead adapter, the fiber-optic bulkhead adapter200has an alignment sleeve219mounted inside each aligned, opposing pairs of female inputs to receive, retain, and align the optical fibers associated with the fiber-optic connectors received by the female inputs. The fiber-optic connectors214and216include a ferrule218that houses the optical fiber217therewithin. The ferrule218serves to protect the optical fiber217and align the optical fiber217within the bulkhead adapter200through engagement of the ferrule218with the alignment sleeve219.

The endface202of a terminated optical fiber is cut and polished to a high degree of precision for purposes of optimizing signal propagation. Each fiber-optic endface202is either “flat” (i.e., orthogonal to the optical axis of the fiber) or cut at an angle. Preferably, each fiber-optic endface202is cut at an angle of 8° from vertical (plus or minus 0.1°) to reduce signal degradation caused by reflection.

Many bulkhead adapters200are duplex in design, such as shown inFIGS. 1 and 2allowing for a send and receive channel within a single housing. It should be apparent to one skilled in the art, however, that simplex bulkhead adapters are also quite common and suitable for use in conjunction with the present invention, as well as multiplexes exceeding two.

The bulkhead adapter200may include a split housing208, female inputs204and206at each end for receiving fiber-optic connectors, such as those referenced by numerals214and216, therewithin. The split housing208is generally an elongate hollow block structure formed by joining a first housing half210to a second housing half212along a pair of opposing mating flanges220and222. Mounted within is the alignment sleeve219into which the ferrule218, and optical fiber217are retained and aligned.

In light of the above discussion of the fiber-optic bulkhead adapter200, the fiber-optic endface cleaning apparatus100will now be discussed. As stated above, the fiber-optic endface cleaning apparatus100includes the housing110, the evacuation system104, the cleaning solvent delivery system106, and the pressurized fluid delivery system108. The housing110is comprised of an interface portion116coupled to or integrally formed with a tubing receiving portion118. The interface portion116is a hollow elongate block structure having outer dimensions substantially similar to the inner dimensions of the female inputs204and206of the fiber-optic bulkhead adapter200to allow the insertion of the interface portion116therein. The interface portion116is configured to orient the components of the cleaning solvent delivery system106and the pressurized fluid delivery system108contained within the interface portion116so that any fluid discharged therefrom will properly impinge the fiber-optic endfaces202, as will be discussed in further detail below.

Joined to the interface portion116is the tubing receiving portion118. The evacuation passageway120, cleaning solvent tubing122, and pressurized fluid tubing124pass through the tubing receiving portion118. The tubing receiving portion118is a triangular block structure, preferably solid in construction with exception of the tubing passing therethrough.

The evacuation system104is comprised of the evacuation passageway120coupled to a vacuum pump (not shown) by well known flexible tubing (not shown.) The vacuum pump may be any well known pump that has sufficient capacity to maintain a negative pressure within the alignment sleeve219during cleaning, despite the injection of a pressurized fluid therein. One such vacuum pump suitable for use with the present invention is a single stage venturi pump, Model No. AVR046H, manufactured by Air-Vac, located in Seymour, Conn. The pump is capable of producing vacuum flow rates up to 118 ml/sec. Preferably, a low level of vacuum is applied to mitigate the entrance of contaminants exterior of the connector through infiltrating cracks or other openings in the connector.

The evacuation passageway120passes through the tubing receiving portion118of the housing110at an angle relative to the horizontally oriented interface portion116of the housing110. As the evacuation passageway120passes through the interface portion116of the housing110, the evacuation passageway120is defined by the inner walls of the interface portion116of the housing110. In the embodiment illustrated, the inner diameter of the evacuation passageway120within the interface portion116is equal to the outer dimensions of a protective housing226that encompasses the alignment sleeve219and related fiber-optic endfaces202, although any diameter that allows adequate volume flow is acceptable. Although an evacuation system is depicted and described, it should be apparent to those skilled in the art, the evacuation system104is optional, and the fiber-optic endface cleaning apparatus100may be effectively used without an evacuation system.

The pressurized fluid delivery system108is comprised of a fluid pressurization unit (not shown), the pressurized fluid tubing124, and a pressurized fluid nozzle130. The fluid pressurization unit delivers a pressurized fluid via flexible tubing (not shown) to the pressurized fluid tubing124for discharge from the pressurized fluid nozzle130. The fluid pressurization unit may be any well known pump or other source that has a sufficient capacity to maintain sufficient flow under sufficient pressure during cleaning. In the illustrated embodiment, a pressurized fluid is delivered within a range of 15 psi to substantially greater values, with a preferred value of 100 psi, for three seconds at a flow rate of 112 ml/sec.

In one embodiment, the pressurized fluid is a pressurized gas provided by selectively releasing pressurized nitrogen from well known commercially available pressurized nitrogen bottles. In another embodiment, the fluid is a pressurized gas such as dry filtered air provided by a well known compressor or pump. In still another embodiment, the pressurized fluid is CO2. In yet another embodiment, the pressurized fluid is deionized air. Although in the illustrated embodiment, the pressurized fluid is described as either nitrogen, air, deionized air, or CO2, it should be apparent to one skilled in the art that other fluids are suitable for use with the present invention, such as liquids and fluids with entrained solid particles. Further, it should be understood that within the meaning of this detailed description, the term “pressurized gas” includes gaseous compounds that may have small amounts of liquids contained therein, such as air having a humidity other than zero. Further still, although a specific pressure, duration and flow rate suitable for use with the present invention have been described for illustrative purposes, it should be apparent to one skilled in the art that these quantities are descriptive in nature. Therefore, other quantities are suitable for use with the present invention and within the scope of the invention. Preferably, the pressurized fluid is filtered to remove any unwanted contaminates.

The pressurized fluid tubing124terminates in a pressurized fluid nozzle130. The pressurized fluid nozzle130is made from any suitable rigid material, such as stainless steel hypodermic needle tubing. In the illustrated embodiment, the nozzle is comprised of extra thin wall, 26-gauge hypodermic needle tubing having an outside diameter of 0.018 inches and an inside diameter of 0.014 inches. The pressurized fluid nozzle130includes a pressurized fluid discharge port or nozzle tip112at the distal end of the pressurized fluid nozzle130.

In the illustrated embodiment the pressurized fluid is preferably filtered through a well known filter arrangement, one such suitable filter arrangement being a reusable syringe filter housing utilizing a fine porosity, medium-fast flow rate, 1.0 μm size particle retention, 13 mm glass fiber membrane, Model No. 66073, manufactured by Pall Gelman Laboratory, located in Ann Arbor, Mich.

The cleaning solvent delivery system106is comprised of cleaning solvent tubing122coupled to a cleaning solvent storage source (not shown). The cleaning solvent tubing122is coupled in fluid communication with a solvent storage source or delivery system (not shown) via flexible tubing (not shown). The cleaning solvent tubing122terminates in a nozzle126having a discharge port or nozzle tip114at the distal end of the nozzle126for delivery of the pressurized gas and cleaning solvent upon the fiber-optic endface202. The cleaning solvent tubing122passes in line with the centerline of interface portion118through both the tubing receiving portion118and the interface portion116of the housing110.

The cleaning solvent tubing122may be made from any suitable rigid material, such as stainless steel hypodermic needle tubing. In the illustrated embodiment, the nozzle is comprised of extra thin wall, 20-guage hypodermic needle tubing having an inside diameter of 0.028 inches. The inside diameter is selected to allow the pressurized fluid tubing124to pass therethrough and sufficiently oversized to result in the formation of an annulus117between the outer surface of the pressurized fluid tubing124and the inner surface of the cleaning solvent tubing122. A venturi effect caused by the passage of pressurized fluid through the pressurized fluid nozzle130draws cleaning solvent from the cleaning solvent storage source (not shown), through flexible tubing connecting the cleaning solvent storage source to the cleaning solvent tubing122, and through the annulus117for eventual discharge from the nozzle tip114. Further, although in the illustrated embodiment the pressurized fluid tubing124is depicted running concentrically within the cleaning solvent tubing122, it should be apparent to one skilled in the art that other configurations are suitable for use with the present invention. For instance, the cleaning solvent tubing122may run within the pressurized fluid tubing124. Alternately, the cleaning solvent tubing122and the pressurized fluid tubing124may be separate and distinct units directed at the endface and/or directed to discharge into the flow path of the other, as should be apparent to one skilled in the art.

It should also be apparent to one skilled in the art that any suitable cleaning solvent able to effectively remove contaminants contained on the endface of the fiber-optic strand is suitable for use in the present invention. The cleaning solvent may be a gas, liquid, solid or a combination thereof. Preferably, the cleaning solvent, if a liquid, has a flashpoint above 50 degrees Celsius. The cleaning solvent may be heated to increase the efficiency of the cleaning solvent. One suitable cleaning solvent is a hydrocarbon and terpene blend solvent, manufactured by American Polywater Corporation, located in Stillwater, Minn., sold under the trademark HP™, product number HPV-16LF. The hydrocarbon and terpene blend is comprised of a medium aliphatic petroleum solvent and a monocyclic terpene. In another embodiment, the cleaning solvent is a cyanide gas, capable of dissolving some plastics. In yet another embodiment, the cleaning solvent is a liquid with soft suspended solids therein. In still yet another embodiment, the cleaning solvent is a mixture of a fluorinated ether, a chlorinated alkalene, and an alcohol. More specifically, the cleaning solvent is a mixture comprising methyl nonafluorobutyl ether, ethyl nonafluorobutyl ether, trans-1,2-dichloreoethylene, and isopropanol, one suitable example being manufactured by 3M™ located in St. Paul, Minn., and other locations worldwide, and sold under the name NOVEC FLUID HFE-72DA.

In the illustrated embodiment, the cleaning solvent is delivered by means of a venturi effect caused by the passing of the pressurized fluid through the pressurized fluid nozzle130. In another embodiment, the cleaning solvent is delivered by a pump. One such suitable pump is a solenoid operated diaphragm pump, manufactured by Clark, located in Hudson, Mass., Model No. DMS 035. The pump is capable of providing a fluid at 5 psi at a flow rate of 160 ml/min. Although a specific pump has been described that is suitable for use with the present invention, it should be apparent to one skilled in the art that any such suitable pump may be used with the present invention without departing from the scope of the invention.

In the illustrated embodiment, approximately 25 microliters of cleaning solvent are delivered per three second cleaning blast. Nonetheless, it should be apparent to one skilled in the art that other quantities and durations are suitable for use with the present invention, and are therefore within the scope of the invention. In the present embodiment the cleaning solvent discharge port or nozzle tip114is preferably located approximately 0.02 inches to approximately 0.20 inches from the endface. However, it should be apparent to one skilled in the art that other distances are appropriate for use with the present invention. It should also be apparent to one skilled in the art that the spacing of the nozzle tip114from the endface affects the back pressure and the effectiveness of the cleaning ability of the present invention. More specifically, if the nozzle tip114is placed too close to the endface, back pressures escalate, decreasing the effectiveness of the cleaning operation. On the other hand, if the nozzle tip114is displaced too far from the endface, the energy of the jet is dissipated prior to impacting the endface202, thereby significantly reducing the cleaning effectiveness of the apparatus. In the illustrated embodiment, a spacing of 0.05 inches is preferred.

In the illustrated embodiment, the cleaning solvent is also preferably filtered through a well known filter arrangement, one such suitable filter arrangement being a reusable syringe filter housing utilizing a fine porosity, medium-fast flow rate, 1.0 μm size particle retention, 13 mm glass fiber membrane, Model No. 66073, manufactured by Pall Gelman Laboratory, located in Ann Arbor, Mich.

Still referring toFIGS. 1 and 2, in light of the above description of the fiber-optic endface cleaning apparatus100, the operation of one embodiment of the fiber-optic endface cleaning apparatus100during a typical cleaning cycle will now be described. First, a fiber-optic connector is removed from the female input204and the interface portion116of the endface cleaning apparatus100is inserted therewithin. The cleaning process is then initiated by pressing a button or similar actuator (not shown). Dry, filtered air at 100 psi is applied at a rate of 112 ml/sec in 3-second bursts through the pressurized fluid tubing124. About 0.01 ml to about 0.05 ml, with a preferred value of approximately 0.025 ml, of a cleaning solvent comprised of a liquid hydrocarbon and terpene solvent mixture, is drawn through the cleaning solvent delivery tubing122in approximately the first 100 milliseconds by a venturi effect created by the flow of filtered air through the pressurized fluid nozzle130.

The pressurized air mixes with the cleaning solvent, thereby creating an aerosol mist of cleaning solvent entrained in a high-speed gas jet. The aerosol mist of cleaning solvent and pressurized gas is charged through the discharge port114of the cleaning solvent nozzle126. The discharge port114is located approximately 0.02 inches to approximately 0.20 inches from the endface with the preferred distance being 0.05 inches. The aerosol mist of cleaning solvent and pressurized gas impinges the endface202, removing any contaminants located thereupon. Vacuum is applied throughout the entire procedure and for a period thereafter through the evacuation passageway120at a rate of approximately 118 ml/sec, thus removing any spent pressurized gas and cleaning solvent, odors, providing general housekeeping, and maintaining the inner portions of the connector200slightly below atmospheric pressure. A drying phase, comprising the application of pressurized gas and evacuation vacuum upon the endface, may be initiated following the cleaning evolution to aid in the removal of any residual cleaning solvent that remains within the alignment sleeve219. Although specific quantities, such as pressures, flow rates, durations, and fluids are disclosed above, it should be apparent to one skilled in the art that other quantities and fluids are suitable for use with the present invention, and are therefore within the scope of the invention.

Referring now toFIGS. 3 and 4, an alternate embodiment of a fiber-optic endface cleaning apparatus300formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus300is capable of interfacing with a fiber-optic connector400, such as the fiber-optic connectors214and216shown inFIGS. 1 and 2, to clean the endfaces of the optical fiber(s) contained therewithin. The fiber-optic endface cleaning apparatus300of this embodiment is similar to the embodiment described above and depicted inFIGS. 1 and 2, with the exception that the fiber-optic endface cleaning apparatus300is designed to provide a pathway330through which an optical imaging axis of a microscope500may extend for viewing the endface402of the connector ferrule418contained within the fiber-optic connector400, and also with the exception that the cleaning is performed once the connector400is removed from the bulkhead adapter. Since the optical features of the microscope500and the general knowledge of the optical nature of the microscope500are well known, these aspects of the microscope500will not be further discussed herein.

The fiber-optic endface cleaning apparatus300includes an evacuation system304, a cleaning solvent delivery system306, and a pressurized fluid delivery system308, all of which are substantially similar to those described for the above embodiment. Although an active evacuation system304is depicted in this embodiment substantially similar to the system described for the above embodiment, it should be apparent to one skilled in the arts that the method of removing debris in this configuration may be done in either an activation (vacuum) or passive (vent) manner. Specifically, it should be apparent to one skilled in the art that the evacuation system304may alternately accomplish the removal of debris through simply passively venting any fluids discharged upon the endface through a suitably designed evacuation system, as opposed to actively applying a vacuum in proximity to the endface as was disclosed for the previous embodiments.

The housing310of the endface cleaning apparatus300is formed by joining or integrally forming a hollow cone-shaped section332to an axially aligned hollow cylindrically shaped section334. The cone shaped section332includes an interface portion316. The interface portion316is a hollow elongate block structure having inner dimensions substantially similar to the outer dimensions of the ferrule418of the fiber-optic connector400to allow the insertion of the ferrule418therein. It should be apparent to one skilled in the art that a similar configuration wherein the interface portion316is designed to interface with inner dimensions of a female input of a bulkhead adapter is a clear extension of this embodiment. The interface portion316is configured to orient the components of the cleaning solvent delivery system306and the pressurized fluid delivery system308contained within the cone-shaped section332so that any fluid discharged therefrom will properly impinge the fiber-optic endface402, as will be discussed in further detail below. The cone-shaped section332allows the placement of the components of the cleaning solvent delivery system306, pressurized fluid delivery system308, and evacuation system304out of the optical pathway330of the microscope500.

Joined to the cone-shaped section332is the cylindrically shaped section334. The evacuation passageway320, cleaning solvent tubing322, and pressurized fluid tubing324pass through the cylindrically shaped section334. The cylindrically shaped section334further includes a receiving aperture336for receiving a head portion502of the microscope500therewithin. When the head portion502of the microscope500engages the receiving aperture336during insertion within the housing310, the receiving aperture336serves to align the optical imaging axis of the microscope500through the optical pathway330that passes through the housing310and upon the endface402of the fiber-optic strand, allowing the user to view the fiber-optic endface402. In this embodiment, the microscope500is inserted after the completion of a cleaning cycle to inspect and view the endfaces402of the optical fiber to verify the effectiveness of the cleaning cycle.

Although in the illustrated embodiment, the microscope500is a separate unit operable to removably engage the endface cleaning apparatus300, it should be apparent to one skilled in the art that the microscope500may be integrally formed or otherwise permanently affixed to the endface cleaning apparatus300without departing from the scope of the invention. Within this alternate embodiment, the user would be able to view the endface during the cleaning cycle or shortly thereafter without removal of the endface cleaning apparatus300from the fiber-optic connector400.

The operation of the alternate embodiment of the endface cleaning apparatus300depicted inFIGS. 3 and 4is substantially similar in operation to the endface cleaning apparatus embodiment described above and depicted inFIGS. 1 and 2with exception of the use of the microscope500and the orientation of the evacuation system304, the cleaning solvent delivery system306and the pressurized fluid delivery system308. Inasmuch as the operation is substantially similar to that described above, it will not be further discussed herein.

Referring now toFIG. 5, a second alternate embodiment of a fiber-optic endface cleaning apparatus600formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus600is capable of interfacing with an interface device, such as those typically used in fiber-optic data transmission equipment and depicted inFIGS. 1 and 2, to clean the endfaces of the optical fibers contained therewithin. The fiber-optic endface cleaning apparatus600of this invention is similar to the embodiment described above and depicted inFIGS. 1 and 2, with the exception that the fiber-optic endface cleaning apparatus600further includes a microscope700integrally formed with the fiber-optic endface cleaning apparatus600to allow the optical imaging of the fiber-optic endfaces of the fiber-optic strands contained within a connector. Since the optical features of a microscope700and the general knowledge of the optical nature of a microscope are well known, these aspects of the fiber-optic endface cleaning apparatus600will not be further discussed herein.

The microscope700is located on a first end of a housing610of the fiber-optic endface cleaning apparatus600, opposite a cleaning apparatus interface portion634located on a second end. The cleaning apparatus interface portion634includes an evacuation system, a cleaning solvent delivery system, and a pressurized fluid delivery system, all of which are substantially similar to those described for the above two embodiments and therefore will not discuss further herein.

In operation, a user selectively inserts either the first or second end within an interface device depending on whether cleaning or inspecting operations are desired. For example, if the user desires to clean a fiber-optic endface contained within the bulkhead adapter, the cleaning apparatus interface portion634is inserted within the bulkhead adapter, and an actuator button636is depressed to initiate cleaning operations. Upon completion of the cleaning operations, the user would subsequently remove the fiber-optic endface cleaning apparatus600and rotate the endface cleaning apparatus600end-to-end, followed by the insertion of an interface portion702of the microscope700within the bulkhead adapter. The interface portion702is designed to interface with a bulkhead adapter such that the optical lens of the microscope may focus upon the fiber-optic endfaces contained within the fiber-optic bulkhead adapter.

Referring now toFIGS. 6–12, an alternate embodiment of a fiber-optic endface cleaning apparatus800formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus800is capable of interfacing with an interface device, such as a fiber-optic bulkhead adapter900, to clean the endfaces of the optical fibers contained therewithin. The fiber-optic endface cleaning apparatus800of this embodiment is similar in operation and structure to the embodiment described above and depicted inFIGS. 1–2, with the exception that the fiber-optic endface cleaning apparatus800further includes a retractable baffle802.

Referring toFIGS. 11 and 12, the baffle802aids in the removal of cleaning solvent remaining within an alignment sleeve822during a cleaning evolution. Moreover, the fiber-optic endface902has a chamfer904located around the periphery of the fiber-optic endface902. It has been found that during cleaning operations, cleaning solvent and/or other fluids may collect in the chamfer904. The chamfer904acts as a protected cavity, partially shielding the cleaning solvent contained therewithin from the pressurized fluid and/or applied vacuum. Thus, while the pressurized fluid is flowing, the fiber-optic endface902remains in a clean and dry state. However, when the flow of the pressurized fluid ceases, the cleaning solvent present in the chamfer904and any contaminants contained therein flow back onto the fiber-optic endface902, recontaminating the endface. The retractable baffle802of the illustrated embodiment aids in the removal of cleaning solvent from the chamfer by concentrating the flow of the pressurized fluid into the chamfer904. Thus, when the baffle802is in an extended position as shown inFIG. 11, the pressurized fluid more directly impinges the cleaning solvents contained in the chamfer904, thereby enhancing cleaning solvent removal.

Focusing now more on the outer structure of the fiber-optic endface cleaning apparatus800, and in reference toFIGS. 6–8, the external components comprising the fiber-optic endface cleaning apparatus800will be described. The fiber-optic endface cleaning apparatus800includes a housing810subdivided into three distinct sections: an interface, section844, a middle section846, and a baffle actuator section848. The interface section844and the baffle actuator section848are joined to the middle section846by well known fasteners840and842. Coupled to the interface section844is an interface tip816. The interface tip816is a hollow, sometimes cylindrical-shaped structure having outer dimensions substantially similar to the inner dimensions of an entry female input906of a fiber-optic bulkhead adapter900(seeFIG. 9) to allow the insertion of the interface tip816therein.

The interface tip816is configured to orient the components of the cleaning solvent delivery system and the pressurized fluid delivery system contained within the fiber-optic endface cleaning apparatus800so that any fluid discharged therefrom will properly impinge the fiber-optic endfaces, as will be discussed in further detail below. Further, the interface tip816or some portion of the interface portion844is preferably configured to allow the interface tip816or at least a portion of the interface portion844to be removed from the endface cleaning apparatus800. Configured as such, the interface tip816or some portion of the interface portion844may be easily removed and exchanged for a different style of interface tip816or interface portion844to accommodate a wide variety of interface devices.

In the embodiment depicted inFIG. 6, interface tip816may be selectively removed from an interface tip receiving port815in the interface portion844and replaced with an alternately shaped interface tip817, thereby allowing the endface cleaning apparatus800to interface with a fiber-optic endface associated with a different shaped interface device. Thus, fiber-optic endface cleaning apparatus800may be selectively configured to be compatible with nearly any interface device. As should be apparent to one skilled in the art, although an interchangeable interface tip816or interface portion844is described with specificity in regard to the above described embodiment only, it should be apparent to one skilled in the art that any of the embodiments described within this detailed description may incorporate this concept therein.

Disposed on the middle section846is an actuator button834and an access port838. By pressing the actuator button834, a user initiates the cleaning process. The access port838, an oblong aperture in the housing810, permits access to a set screw862disposed within the fiber-optic endface cleaning apparatus800, the purpose of which will be described in further detail below. Further, the access port838allows the position of a baffle802to be visually confirmed. Further still, the access port838allows the manual activation of the baffle between an extended position and a retracted position.

The baffle actuator section848, as the name implies, houses a baffle actuator870for selectively positioning a baffle between extended and retracted positions, as will be described in further detail below. A needle valve adjustment screw836for fine tuning the operation of the baffle actuator870is disposed on the outer surface of the baffle actuator section848. Also disposed on the outer surface of the baffle actuator section848is an access port850. The access port850allows the passage of an electrical wiring umbilical cord (not shown for clarity) for delivery of electrical control signals and power to select internal components of the fiber-optic endface cleaning apparatus800, such as the baffle actuator870. Further, the access port850allows the passage of a section of pressurized fluid delivery tubing and a section of cleaning solvent delivery tubing (not shown for clarity), substantially similar in operation and structure as the solvent tubing122and the pressurized fluid tubing124shown inFIG. 1, into the fiber-optic endface cleaning apparatus800.

Focusing now more on the internal structure of the fiber-optic endface cleaning apparatus800, and in reference toFIGS. 8 and 9, the internal components comprising the fiber-optic endface cleaning apparatus800will be described. The middle section846is comprised of a baffle return spring chamber854and a solvent delivery valve chamber860. The baffle return spring chamber854is cylindrical in shape and runs longitudinally through the fiber-optic endface cleaning apparatus800. The baffle return spring chamber854houses a baffle return spring852. The baffle return spring852biases the baffle802in a retracted position, as shown inFIG. 8. The baffle return spring852biases the baffle802by exerting a spring force upon a rod clamp864. The rod clamp864is reciprocatingly disposed within the baffle return spring chamber854and has a spring seat866that engages a distal end of the baffle return spring852and an actuator seat868that communicates with a baffle actuator870. The rod clamp864is coupled to an actuating rod872through the use of a well known set screw862.

Located adjacent to and in a parallel orientation with the baffle return spring chamber854is a solvent delivery valve chamber860. The solvent delivery valve chamber860houses a solvent delivery valve return spring858and a solvent delivery valve856. The solvent delivery valve return spring858biases the solvent delivery valve856in a closed position until actuated by fluid pressure from solvent port898into an open position, thereby allowing delivery of a cleaning solvent to the fiber-optic endface902. Thus, the solvent delivery valve acts as a check valve. As should be apparent to one skilled in the art, the valve configuration herein described may be replaced by any number of actuator/valve combinations well known in the art, such as electromechanical, pneumatic, hydraulic, and mechanical actuators.

Focusing now on the interface section844, the interface section844is comprised of a fiber-optic endface receiving chamber880sized to receive a protective housing926that partially encompasses the fiber-optic endface902and alignment sleeve822. Disposed in an annular channel formed on the inner wall of the fiber-optic endface receiving chamber880is a well known O-ring884. The O-ring884acts as a seal between the protective housing926of the alignment sleeve822and the fiber-optic endface receiving chamber880, thereby impeding the passage of fluids between the protective housing926and the inner surface of the fiber-optic endface receiving chamber880. It should be apparent to one skilled in the art that this seal may alternately be formed by any number of methods well known in the art, or alternately, may be omitted if ambient contamination is not a consideration.

Referring now toFIGS. 8,9, and12, disposed within the fiber-optic endface receiving chamber880is the baffle802. The baffle802is comprised of a base portion886integrally formed to a concentrically oriented hollow cylinder888. The base portion886is formed from four legs812disposed radially outward from the cylinder888so that each leg812is spaced 90° from the closest adjacent legs812. Thus, relief gaps814are formed between adjacent legs812for permitting the passage of evacuation gases thereby. The base portion886of the baffle902is adapted to receive an actuating rod872therein. Upon actuation of the actuating rod872by the baffle actuator870, the baffle802is reciprocally driven within the fiber-optic endface receiving chamber880through the pressure exerted by the actuating rod872upon the baffle802via the base portion886.

The cylinder888has a flared distal end890, having guiding members, such as five longitudinally aligned guiding ribs892equally spaced around the flared distal end890. The guiding ribs892aid in the alignment of the baffle802within the alignment sleeve822, which partially encloses the endface902, while still allowing the flow of fluids for removal from the connector900between adjacent guiding ribs892. Although the illustrated embodiment is shown with five guiding ribs892, it should be apparent to one skilled in the art that other quantities of guiding ribs892are suitable for use with the present invention, such as three, four, or six for example.

Passing through a hollow cylindrical passage826in the baffle802is a pressurized fluid nozzle896and a cleaning solvent nozzle894. The pressurized fluid nozzle896and the cleaning solvent nozzle894are substantially similar in construction and operation as that of the pressurized fluid nozzle130and cleaning solvent nozzle126depicted in theFIG. 2, and therefore will not be discussed in further detail here.

In fluid communication with the cleaning solvent nozzle894is a cleaning solvent passageway899. The cleaning solvent passageway899is in fluid communication with the solvent delivery valve856, a solvent port vent832, and also with solvent delivery tubing, not shown but similar to the solvent delivery tubing122shown inFIG. 1. The solvent port vent832is open to the atmosphere to allow atmospheric air into the endface cleaning apparatus800during solvent flow. Moreover, the solvent port vent832aids in solvent flow by impeding vapor lock formation by the introduction of near atmospheric pressure air into the solvent flow. Air entering the solvent port vent832during solvent flow is filtered via a filter830. In the illustrated embodiment, the filter830is a 1 micron rated glass fiber filter, although it should be apparent to one skilled in the art that other filters are suitable for use in the present invention, and further, that the filter may be eliminated if ambient contamination is not a consideration.

The solvent delivery valve856is situated in the cleaning solvent passageway899, between the solvent port vent832and the cleaning solvent nozzle894. The solvent delivery valve856selectively controls the passage of a solvent to the cleaning solvent nozzle894. Moreover, the solvent delivery valve856is actuated between a flow and no flow condition by fluid pressure applied to solvent port898during cleaning.

The operation of the alternate embodiment of the endface cleaning apparatus800depicted inFIGS. 6–11is substantially similar in operation to the endface cleaning apparatus embodiment described above and depicted inFIGS. 1 and 2with exception of the use of the baffle802. Inasmuch as the operation is substantially similar to that described above, the aspects of operation substantially similar to that described above will not be further discussed herein. As for the baffle802, the baffle is actuatable between the retracted position shown inFIG. 8and extended position shown inFIG. 9. By selectively positioning the baffle802as such, the amount of residual cleaning solvent remaining in the connector900after a cleaning evolution is substantially reduced.

More specifically and as best seen inFIG. 11, the fiber-optic endface902has a chamfer904located around the periphery of the fiber-optic endface902as discussed above. The retractable baffle802of the illustrated embodiment aids in concentrating the flow of the pressurized fluid into the chamfer904. Thus, with the baffle in the extended position, the pressurized fluid is directed in a flow path824which more directly impinges the cleaning solvents contained in the chamfer904, thereby enhancing cleaning solvent removal during a drying/solvent removal phase of the cleaning evolution, when the pressurized fluid, absent cleaning solvent, is directed at the endface902.

Inasmuch as the baffle802may impede the flow of cleaning solvent and pressurized fluid during cleaning operations, the baffle802may be selectively retracted during the application of the cleaning solvent and pressurized fluid so as to allow the unfettered flow of these fluids during cleaning as shown inFIG. 9. Although a retractable baffle is shown, it should be apparent to one skilled in the art that the baffle may be rigidly held in an extended position. Further still, although the illustrated embodiment depicts a baffle of certain shape and construction, it should be apparent to one skilled in the art that the baffle may take many various forms. For instance, the baffle may be formed by flaring the end of the cleaning solvent nozzle894outwards. Therefore it should be apparent to one skilled in the art that the baffle is defined by its ability to enhance the flow of fluids within the chamfer904and across the endface902, and is therefore not limited to the illustrated form shown inFIGS. 8–12.

While the baffle previously described is effective at reducing the volume of solvent retained by the chamfer904, an alternate treatment of the problem of recontamination of the fiber endface902by flow of the solvent back onto the cleaned surface is to increase the surface tension of the retained fluid. The surface tension may be increased by adding a chemical agent, such as water, during a second fluid application stage, which would tend to minimize the tendency of the retained fluid to wick across the cleaned surface recontaminating the surface. As should be apparent to one skilled in the art, the chemical agent may be delivered upon the endface by any suitable means. For example, the chemical agent may be applied in the same manner as the solvent by simply toggling the solvent delivery tubing between fluid communication with a solvent source and fluid communication with a chemical agent source, as should be apparent to one skilled in the art. Alternately, a third nozzle may be disposed in the housing for discharging the chemical agent directly upon the endface, or for dispensing the chemical agent into the pressurized fluid flow for delivery upon the endface.

Referring now toFIGS. 13 and 14, an alternate embodiment of a fiber-optic endface cleaning apparatus1100formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus100is capable of interfacing with an interface device1103to clean an endface1104of an optical fiber106at least partially disposed therewithin. The fiber-optic endface cleaning apparatus1100of this embodiment is similar in operation and structure to the embodiments described above, and most specifically the embodiment depicted inFIGS. 1 and 2. However, the endface cleaning apparatus1100ofFIGS. 13 and 14differs most notably from the above described embodiments in that the endface cleaning apparatus1100engages the endface1104during cleaning operations. More specifically, a nozzle1110of the endface cleaning apparatus1100has a plurality of fingers or extensions1112extending outward from the nozzle1110to engage and thereby maintain a selected separation distance between the endface1104and the nozzle1110during cleaning operations. The method of combining fluid and solvent also differs, i.e. the solvent is injected under pressure into the fluid stream rather than being “drawn” into the stream by a venturi effect.

The endface cleaning apparatus1100includes a housing1114, a fluid dispensing assembly1116, and an evacuation assembly1118. The housing1114is made of any rigid or semi-rigid material, such as plastic, metal, etc. The housing1114provides an enclosure to partially house portions of the fluid dispensing and evacuation assemblies1116and1118. The housing1114is preferably configured to be easily gripped by a hand of a user.

The housing1114also includes a front section1115. The front section1115includes the components of the endface cleaning apparatus1100extending outward toward the endface from a joint indicated by reference numeral1119. Preferably, the front section1115of the housing may be selectively removed from the housing1114, for example by unthreading the front section1115from the remaining portion of the housing at the threaded joint1119. Once removed, the front section1115may be replaced with an alternately shaped front section, such as the one depicted and described in relation toFIG. 20, thereby allowing the endface cleaning apparatus1100to interface with a fiber-optic endface associated with a differently shaped interface device. Thus, the fiber-optic endface cleaning apparatus100may be selectively configured to be compatible with nearly any interface device.

The fluid dispensing assembly1116includes a solvent delivery system1120and a pressurized fluid delivery system1122similar in construction and operation to the cleaning solvent delivery system106and the pressurized fluid delivery system108depicted and described in relation toFIGS. 1 and 2. The solvent delivery system1120includes a solvent pipe1121for conveying a solvent therein. The pressurized fluid delivery system1122also includes a pipe1123, the pipe1123suitable for conveying a pressurized fluid therein. The solvent pipe1121discharges into pipe1123through port1125. Thus, downstream of port1125, the pipe of the pressurized fluid delivery system1122conveys a fluid and solvent mixture, preferably wherein the solvent is atomized and mixed among a gaseous pressurized fluid.

The remaining aspects of the solvent and pressurized fluid delivery systems1120and1122are similar to aspects of previously described cleaning solvent delivery systems and pressurized fluid delivery systems. Therefore, for the sake of brevity, this description will not repeat herein aspects of the endface cleaning apparatus1100which are substantially similar to solvent and fluid delivery systems described above, such as the solvent and fluid delivery systems106and108of the endface cleaning apparatus100described and depicted in relation toFIG. 1.

The fluid dispensing assembly1116includes an interface portion1124. In the illustrated embodiment, the interface portion1124is sized and configured to be cooperatively received within the interface device1103to align the interface device1124within the interface device1103. More specifically, the interface portion1124is sized and configured to be received by the interface device1103such that the cleaning fluids and solvents discharged from the fluid dispensing assembly1116are directed at the endface1104when the interface portion1124is received by the interface device1103.

In the case of the illustrated embodiment, the interface portion1124is sized and configured to have outer dimensions that correspond to the inner dimension of an alignment sleeve1108of the interface device1103. Thereby, when the interface portion1124is cooperatively received by the alignment sleeve1108, the components of the fluid dispensing assembly1116are positioned so that any fluid discharged therefrom will impinge the fiber-optic endface1104.

More specifically, the interface portion1124may include a plurality of guiding members, such as three longitudinally aligned guiding ribs1125equally spaced around the outer circumference of the interface portion1124. The guiding ribs1125aid in the alignment of the interface portion1124within the alignment sleeve1108, while still allowing the flow of fluids outward between adjacent guiding ribs1125for removal escape from the interface device1103.

The interface portion1124of the fluid dispensing assembly1116includes a nozzle tip1110, wherein at least a majority of the pressurized fluid and solvent are released from the fluid dispensing assembly1116. The interface portion1124also includes one or more fingers or extensions1112(three shown) which extend outward and parallel with the longitudinal axis of the interface portion1124. The distal ends of the extensions1112are adapted to engage the endface1104of the optical fiber1106. The extensions have a selected length1126, wherein when the extensions1112engage the endface1104, the nozzle tip1110is separated from the endface by the selected length1126. Preferably, the selected length is between about 0.015 and about 0.25 inches.

In the illustrated embodiment, the endface1104is biased toward the fiber-optic endface cleaning apparatus1106such that when the extensions1112engage the endface1104, the endface1104may be displaced in the direction opposite of the endface cleaning apparatus1100(i.e., to the right with reference toFIG. 13). Thus, with the endface biased as described, the separation distance between the endface1104and the nozzle tip1110is maintained, despite some variability between the separation distance of the interface device1103and the endface cleaning apparatus100. The user maintains a selected engagement force between the interface portion1124of the fluid dispensing assembly1116and the fiber-optic endface1104.

Referring now toFIG. 15, an alternate embodiment of a fiber-optic endface cleaning apparatus1200formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus1200is capable of interfacing with an interface device, such as the interface device1103depicted inFIG. 13, to clean an endface of an optical fiber contained therewithin. The fiber-optic endface cleaning apparatus1200of this embodiment is similar in operation and structure to the embodiments described above, and most specifically to the embodiment depicted inFIGS. 13 and 14, with a few exceptions. For instance, the endface cleaning apparatus1200is adapted to couple to a first container1202containing a pressurized fluid and a second container1204containing a solvent. Further, the cleaning assembly contains a control system1206for controlling the dispensing of the fluid and solvent upon the endface.

The endface cleaning apparatus1200includes a housing1208. The housing includes a first passageway1212coupling the contents of the pressurized fluid container1202in fluid communication with a mixing chamber1216. The housing1208also includes a second passageway1220coupling the contents of the solvent container1204in fluid communication with the mixing chamber1216. The housing further includes a control system bore1218, which houses the majority of the components of the control system1206.

The housing1208also includes a first attachment device1210, the first attachment device1210adapted to permit the removable coupling of the pressurized fluid container1202by any well known means, such as by a threaded connection, press fitting, etc. The housing1208also includes a second attachment device1222adapted to permit the removable coupling of the solvent container1204by any well known means, such as by a threaded connection, press fitting, etc.

The control system1206selectively controls the duration, sequence, timing and quantities of pressurized fluid and solvent directed upon an endface of an optical fiber. The control system1206selectively controls the delivery of the pressurized fluid and solvent by selectively blocking and unblocking the first and second passageways1212and1220.

The control system1206includes a pressurized fluid dispensing mechanism1224, and a solvent metering mechanism1226. The fluid dispensing mechanism1224includes a piston1228concentrically coupled to a first end of a center shaft1230. An actuation mechanism1232, which in the illustrated embodiment is a button, is coupled to a second end of the center shaft1230. The solvent metering mechanism1226includes a cylindrical passage1234along the centerline of a cylindrically shaped main body1236, the cylindrical passageway1234sized and configured to reciprocatingly receive the center shaft1230of the fluid dispensing mechanism1224. Thus, the solvent metering mechanism1226is free to slide longitudinally along the length of the center shaft1230. The solvent metering mechanism1226further includes a piston1238disposed on one end of the main body1236of the solvent metering mechanism1226.

A first biasing device1240, one suitable example being a spring, biases the fluid dispensing mechanism1224in a direction opposite of that depicted by the arrow indicated by reference numeral1234to the at rest position indicated inFIG. 15. A second biasing device1242, one suitable example being a spring, biases the solvent metering mechanism1226in the direction opposite of that depicted by the arrow indicated by reference numeral1234to the at rest position indicated inFIG. 15.

The control system bore1218may be subdivided for purposes of this discussion into two sections. The first section1244is of a reduced diameter chosen to match closely the outer diameter of the piston1228of the fluid dispensing mechanism1224and the main body1236of the solvent metering mechanism1226. The second section1246is of an increased diameter chosen to match closely the outer diameter of the piston1238of the solvent metering mechanism1226. The differences in diameter between the first and second sections1244and1246causes a step1256to be formed at the interface between the first and second sections1244and1246.

Focusing on the second passageway1220, the second passageway includes a first check valve1248and a second check valve1250. Both check valves1248and1250comprise balls1252biased in a closed position against a valve seat by a biasing device, such as a spring, to normally impede solvent from traveling from the solvent container1204to the second section1246and from the second section1246to the mixing chamber1216. Further, the check valves1248and1250impede flow of the solvent from the mixing chamber1216to the second section1246, and from the second section1246to the solvent container1204.

In light of the above description of the components of the fiber-optic endface cleaning apparatus1200, the operation of the endface cleaning apparatus will now be described. To begin operation, the actuation mechanism1232is depressed by a user in the direction of the arrow indicated by reference numeral1234. Pressing the actuation button in the direction of arrow1234causes a corresponding motion of attached piston1228such that the first passageway1212is no longer obstructed by the piston1228. Thus, pressurized fluid flows from the pressurized fluid container1202, through the first passageway1212, into the mixing chamber1216, and is discharged upon the endface.

As the actuation mechanism1232is pressed further in the direction of arrow1234, the actuation button1232contacts the piston1238of the solvent metering mechanism1226, initiating movement of the solvent metering mechanism1226in the direction of arrow1234. This causes a pressure increase in the solvent contained in a solvent metering cavity1260of the second section1246. The solvent metering cavity1260is defined for the illustrated embodiment as the portion of the second section1246bounded by the step1256at one end, the piston1238at an opposing end, the inner wall of the second section1246of the control system bore1218, and the outer surface of the main body1236of the solvent metering mechanism1226. The pressure increase in the solvent metering cavity1260causes the ball1252of the first check valve1248to lift off of its seat, allowing solvent to enter into the mixing chamber1216. As the motion of the actuation mechanism1232stops, the pressure increase in the solvent metering cavity1260ceases, and the biasing device returns the ball1252of the first check valve1248to its seat, impeding the further flow of solvent into the mixing chamber1216. However, the flow of pressurized fluid continues as the first passageway1212remains unobstructed.

The amount of solvent delivered into the mixing chamber1216is substantially equal to a volume of a solvent metering cavity1260. Preferably, the predetermined volume of the solvent metering cavity1260is equal to between about 0.01 ml and about 0.05 ml, with a preferred volume of 0.025 ml.

When the actuation mechanism1232is partially released by the user, the movement of piston1238in the direction opposite arrow1234causes a vacuum to be created in the solvent metering cavity1260. This vacuum lifts the ball1252of the second check valve1250and draws solvent into the solvent metering cavity1260, preparing the endface cleaning apparatus1200for another cleaning cycle. As the actuation mechanism1232is completely released by the user, the piston1228of the fluid dispensing mechanism1224obstructs the first passageway1212, cutting off the flow of pressurized fluid into the mixing chamber.

Focusing now on the timing of the flow of pressurized fluid and the solvent during operation, when a user initially depresses the actuation mechanism1232, only the fluid dispensing mechanism1224is moved, partially un-obstructing the first passageway1212. This permits pressurized fluid only to be directed upon the endface. As the actuation mechanism1232is pressed further in the direction of arrow1234, the base of the actuation mechanism1232contacts the solvent metering mechanism1226. This causes an increase in the pressure of the solvent contained within the solvent metering cavity1260. This increase in pressure causes the first check valve1248to be actuated and a selective quantity of solvent to be released into the mixing chamber1216. The pressurized fluid and solvent mix in the mixing chamber as they are conveyed along the mixing chamber and discharged out a nozzle1254of the endface cleaning apparatus1200.

As the selected quantity of solvent is removed from the second section1246of the control system bore1218and dispensed upon the endface, the flow of pressurized fluid continues, continuing to displace and/or evaporate the solvent and contaminates from the endface. The flow of the pressurized fluid continues until the actuation mechanism1232is fully released.

The above process may be repeated until the endface is cleaned to within selected parameters. As should be apparent to those skilled in the art, during a cleaning operation, a blast of pressurized fluid only may be used to attempt to clean the endface. If this is unsuccessful in yielding satisfactory results, the endface cleaning apparatus1200may be used to deliver both the pressurized fluid and the solvent. Although an evacuation system is not depicted with the illustrated embodiment, it should be apparent to those skilled in the art that the endface cleaning apparatus1200may be modified to so include.

Referring now toFIGS. 16–18, an alternate embodiment of a fiber-optic endface cleaning apparatus1300formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus1300includes a fluid dispensing assembly1302which is substantially similar in operation and construction to the fluid dispensing assembly of the embodiment depicted inFIG. 13, and therefore will not be described in detail herein for the sake of brevity. The fiber-optic endface cleaning apparatus1300of this embodiment varies mostly from that depicted inFIG. 13in that the endface cleaning apparatus1300includes a contact cleaning assembly1304. The contact cleaning assembly1304is adapted to engage and clean a fiber-optic endface1306through physical contact.

More specifically, the contact cleaning assembly1304includes an interface portion1308, the interface portion1308adapted to be received within an interface device1310, such as the interface device1103depicted inFIG. 13. Preferably, the interface portion1308is sized and configured to be received within an alignment sleeve1312of the interface device1310.

The contact cleaning assembly1304includes an engagement member1314coupled to the interface portion1308, the engagement member1314adapted to engage the endface1306and remove contaminates on the endface1306, such as embedded or pressed on contaminates, through physical contact. For the purposes of this detailed description, physical contact is defined as contact between a solid material and a contaminate on the endface. Therefore, the definition of physical contact as defined herein does not include the contact between a liquid or gas alone and a contaminate on the endface.

The contact cleaning assembly1304includes a driver1318. The driver1318is coupled to the interface portion1308or alternately, the engagement member itself, and is operable to move the engagement member1314upon the endface1306to dislodge and/or remove any contaminates present on the endface1306. The driver1318may be any suitable mechanism for moving the engagement member, such as a motor or a solenoid. In the illustrated embodiment, the driver1318is a motor operable to rotate (spin) the engagement member1314about an axis substantially collinear with the center axis of the optical fiber1320.

Although in the illustrated embodiment the engagement member1314is described as being moved relative to the endface in a rotating manner, it should be apparent to those skilled in the art that alternate modes of movement are suitable for use with the illustrated embodiment and are within the spirit and scope of the present invention. For instance, the driver1318may move the engagement member1314along the endface in a linear, side to side motion, orbital motion, random motion, or may spin the engagement member1314in an axis other than the axis of the optical fiber1320, such as one perpendicular to the axis of the optical fiber1320. Further, a driver1318is depicted for moving the engagement member, it should be apparent to those skilled in the art that the engagement member1314may be manually moved by the operator.

In the illustrated embodiment, the engagement member1314is comprised of a plurality of brush bristles1316formed from a material that is preferably softer than the material of the endface1306, such as plastic, to impede scratching of the endface1306. Although the engagement member1314is illustrated and described as being comprised of a plurality of bristles1316, it should be apparent to those skilled in the art that the engagement member1314may be formed from other materials, preferably solid materials operable to contact the endface without causing significant damage to the endface, such as fibrous materials, fabrics, foams, etc.

The interface portion1308of the contact cleaning assembly1304may be removably attached to the endface cleaning apparatus1300. Thus, the interface portion1308may be removed and interchanged with an alternately shaped interface portion (not shown) adapted to be received within an alternately shaped interface device (not shown). Likewise, the engagement member1314may be removably attached to the endface cleaning apparatus1300. Thus, the engagement member1314may be removed and interchanged with an alternately shaped engagement member (not shown) adapted to be received within an alternately shaped interface device (not shown).

In light of the above description of the components of the endface cleaning apparatus1300, the operation, of the endface cleaning apparatus1300will not be described. In a preferred mode of operation, the fluid dispensing assembly1302is interfaced with an interface device and operated as described for the endface cleaning apparatus1100depicted and described in relation toFIG. 13. If the application of the fluid and solvent was incapable of removing all contaminates from the endface, then the endface cleaning apparatus1300may be rotated 180 degrees and the contact cleaning assembly1304interfaced with the interface device. More specifically, the user inserts the interface portion1308of the contact cleaning assembly1304within the interface device such that the engagement member1314engages the endface. The engagement member1314is moved across the endface by the spinning motion imparted by the driver1318, such that the bristles1316of the engagement member1314engage and dislodge any contaminates present on the endface. The contact cleaning assembly1304may then be removed from the interface device. The fluid dispensing assembly1302is then re-interfaced with the interface device, and the endface cleaned by application of the fluid and solvent, removing any contaminates dislodge through the contact cleaning assembly1304. This process is continued until the endface is cleaned to within specifications.

Referring now toFIG. 19, an alternate embodiment of a fiber-optic endface cleaning apparatus1400formed in accordance with the present invention will now be described. The fiber-optic endface cleaning apparatus1400includes a fluid dispensing assembly1402, an evacuation assembly1404, a contact cleaning assembly1406, and a endface viewing device, such as a microscope1408. Inasmuch as the fluid dispensing assembly1402is substantially similar to the fluid dispensing assembly depicted and described in relation toFIG. 13, the contact cleaning assembly1406is substantially similar to the contact cleaning assembly depicted and described in relation toFIGS. 16–18; and the microscope1406is substantially similar to the microscope depicted and described in relation toFIGS. 3–4, this detailed description will focus only on the differences between the components of this embodiment not previously described in the above described embodiments.

The microscope1408of the endface cleaning apparatus1400is designed and configured to view a fiber-optic endface1412to aid a user in determining the optical clarity of the endface1412, i.e. to determine if the endface1412is damaged or to determine whether or not contaminates are present on the endface1412which may degrade the performance of the optical fiber1416. A pathway is maintained free of obstructions between the microscope1408and the endface1412such that an optical imaging axis1418of the microscope1408may reach unobstructed the endface1412of an interface device1414. Since the optical features of the microscope1408and the general knowledge of the optical nature of the microscope1408are well known, these aspects of the microscope1408will not be further discussed herein.

The fluid dispensing assembly1402includes a fluid passageway1410for containing and directing a mixture of a pressurized fluid and a solvent upon the endface1412of the interface device1414, such as the optical fiber connector depicted. The fluid passageway1410terminates in a nozzle tip1420. The fluid passageway1410and nozzle tip1420are positioned to be disposed out of the way of the optical imaging axis1418so as not to impede and or obstruct the viewing of the endface1412by the microscope1408.

The evacuation system1404includes a vacuum passageway1422for containing and directing a vacuum upon the endface1412. The vacuum passageway1422terminates in a nozzle tip1424. The vacuum passageway1422and nozzle tip1424are positioned to be disposed out of the way of the optical imaging axis1418so as not to impede and or obstruct the viewing of the endface1412by the microscope1408.

In the illustrated embodiment, the contact cleaning assembly1406includes an actuation member1428. The actuation member1428is formed from an elongate arm, wherein an engagement member1426is disposed upon a distal end of the elongate arm. The actuation member1428is configurable between a first position, wherein the actuation member1428is shown in solid lines, and in a second position, wherein the actuation member1428is shown in phantom.

In the first position, the actuation member1428is disposed such that the contact cleaning assembly1406is displaced away from the optical image axis1418of the microscope1408. Therefore, when the actuation member1428is in the first position, the contact cleaning assembly1406is disposed out of the way of the optical imaging axis1418so as not to impede and or obstruct the viewing of the endface1412by the microscope1408.

In the second position, the actuation member1428is disposed such that the engagement member1426of the contact cleaning assembly1406is in engagement with the endface1412such that the engagement member1426may physically contact the endface1412to aid in removing contaminates therefrom. The actuation member1428may be actuated between the first and second positions by any well known means in the art, such as by an electrical, air, mechanical, hydraulic or other type of actuator, or by manual manipulation by the user.

The contact cleaning assembly1406includes the engagement member1426, the engagement member adapted to engage and remove contaminates from the endface1412through physical contact. The engagement member1426may be any material operable to contact the endface without causing significant damage to the endface1412. As described for the embodiment depicted inFIGS. 16–18, the contact cleaning assembly1406may include a driver (not shown) operable to move the engagement member1426upon the endface1412to dislodge and/or remove any contaminates present on the endface1412. In the illustrated embodiment, the driver is operable to move the engagement member across the endface of the optical fiber.

Although in the illustrated embodiment, the engagement member1426is described as being moved across the endface, it should be apparent to those skilled in the art that alternate modes of movement are suitable for use with the illustrated embodiment and are within the spirit and scope of the present invention. For instance, the driver may move the engagement member1426along the endface in a side to side motion, linear motion, rotating motion, orbital motion, random motion, or may spin the engagement member1426in an axis other than one parallel with the optical fiber1320, such as one perpendicular to the axis of the optical fiber1320. Alternately, the engagement member1426may be manually manipulated.

In the illustrated embodiment, the engagement member1426is comprised of a plurality of brush bristles formed from a material that is preferably softer than the material of the endface1412, such as plastic. Although the engagement member1426is illustrated and described as being comprised of a plurality of bristles, it should be apparent that the engagement member1426may be formed from other materials, and preferably non-abrasive materials, such as fibrous materials, fabrics, foams, solid materials, etc.

In operation, a preferred manner of use is to steadily increase the aggressiveness of the cleaning operations until the endface is clean. For instance, a user may first examine the endface to determine if the endface requires cleaning. If the endface does require cleaning, a vacuum may be applied to try to remove any contaminates from the endface. If this is not successful, a blast of pressurized fluid only may be applied in a further attempt to clean the endface. If this is not successful, a blast of fluid with solvent mixed therein may be applied to clean the endface. If this is not successful, the engagement member may be actuated to engage and clean the endface, accompanied by fluid and/or solvent or without accompanying fluid and/or solvent. Conducting cleaning operations in this manner ensures that the least intrusive cleaning regime is used to clean the endface. Although a preferred manner of use is described and illustrated, it should be apparent to those skilled in the art that the manner of cleaning the endface may deviate from the preferred manner of cleaning described above without departing from the spirit and scope of the present invention. For instance, a user may not follow a stepped approach, and apply the fluid, solvent, vacuum, and engagement member simultaneously as an initial step in the cleaning process.

Referring now toFIG. 20, an alternate embodiment of a fiber-optic endface cleaning apparatus1500formed in accordance with the present invention will now be described. Inasmuch as the endface cleaning apparatus1500is substantially similar to the endface cleaning apparatus depicted and described in relation toFIGS. 13 and 14, this detailed description will only focus on the differences between the components of this embodiment not previously described above. Generally, these differences include the inclusion of multiple nozzle tips1502and1504for engaging and/or cleaning two fiber-optic endfaces (not shown) simultaneously or in succession without removing the endface cleaning apparatus1500from the interface device (not shown). Further, the nozzle tips1502and1504are biased toward the endfaces by a biasing device1506, which in the illustrated embodiment, is a spring.

Referring toFIGS. 1 and 20, the endface cleaning apparatus1500ofFIG. 20is adapted to interface with an interface device having a plurality of endfaces disposed therein, such as the interface device shown inFIG. 1, the interface device including a fiber-optic bulkhead adapter200and a pair of fiber-optic connectors214and216. More specifically, a fluid dispensing assembly1508of the endface cleaning apparatus1500is adapted to simultaneously engage and dispense a pressurized fluid and solvent upon each of the endfaces-disposed within the interface device. To accomplish this, the endface cleaning apparatus includes a branched interface portion1510, such that the interface portion1510includes a first interface portion1510A and a second interface portion1510B. The first interface portion1510A is configured to be received by the first female input204of the fiber-optic bulkhead adapter200and the second interface portion1510B is configured to be received by the second female input206of the fiber-optic bulkhead adapter200. Thus, during operation, the endfaces contained within the each of the female inputs204and206may be simultaneously cleaned.

Although the fluid dispensing assembly1508of the endface cleaning apparatus ofFIG. 20is depicted and described as having two nozzle tips1502and1504, it should be apparent to those skilled in the art that the endface cleaning apparatus1500may alternately have any number of nozzle tips, including 1 and all numbers greater. Further, although the endface cleaning apparatus ofFIG. 20is depicted and described as simultaneously cleaning both endfaces, it should be apparent that the endface cleaning apparatus may be suitably adapted to clean the endfaces in succession to one another, rather than simultaneously, without departing from the spirit and scope of the present invention.

In the illustrated embodiment, the interface portion1510is biased outward, toward a fiber-optic endface such that when extensions1512of the nozzle tips1502and1504engage the endfaces, the interface portion1510may be displaced in the direction of the endface cleaning apparatus1500, i.e. away from the endfaces. Thus, with this configuration, the separation distance between the endfaces and the nozzle tips1520is maintained, despite movement between the interface device and the endface cleaning apparatus1500. Further, a selected engagement force between the interface portion1510of the fluid dispensing assembly1508and the fiber-optic endfaces is maintained during engagement of the extensions1512with the endfaces. This, among other things, aids in impeding damage to the endfaces through the extensions1512exerting excessive force upon the endfaces. In the illustrated embodiment, the interface portion1510is biased toward the endfaces by a spring1506, the spring extending between a portion of a housing1514of the endface cleaning apparatus1500and a base1516of the interface portion1510. However, it should be apparent to those skilled in the art that alternate biasing means are suitable for use with and within the spirit and scope of the present invention.

Referring now toFIG. 21, an alternate embodiment of a front section1600formed in accordance with the present invention will now be described. The front section1600is suitable to removably attach to the threaded joint1119of the endface cleaning apparatus1100depicted and described in relation toFIG. 13. The front section1600is adapted to clean a plurality of fiber-optic endfaces associated with a plurality of optical fibers1636. The optical fibers1636are partially contained within a ribbon connector1608associated with an interface device1604, the interface device also including a bulkhead adapter1606. Inasmuch as the front section1600is substantially similar in operation and structure to the front section1115of the endface cleaning apparatus1100depicted and described in relation toFIGS. 13 and 14, this detailed description will only focus on the differences between the components of this embodiment not previously described in the above described embodiments.

Generally, these differences include the modification of an interface portion1610of a fluid dispensing assembly for or cleaning fiber-optic endfaces (not shown) associated with the ribbon connector1608disposed within the interface device1604. More specifically, the well known ribbon connector1608includes a “flat” or rectangular ferrule1614having a plurality of fiber-optic endfaces disposed therein. The interface portion1610of the fluid dispensing assembly includes a cooperatively shaped tip portion1616adapted to terminate in proximity to the distal end1618of the ferrule1614. More specifically, the tip portion1616terminates in a nozzle1622disposed about 20 thousands of an inch from the distal end1618of the ferrule1614, creating a gap1626between the distal end1618of the ferrule1614and the tip portion1616. The approximately 20 thousands of an inch separation distance formed by the gap1626is maintained by two posts1630which engage the connector1608.

The ribbon connector1608may include two alignment pins1632which extend outward from the connector1608. The interface portion1610may include two pin receiving portions1634adapted to receive the alignment pins1632. The interface portion1610may further include a vacuum passageway1624disposed around the tip portion1616. The vacuum passageway1624is coupled to a well known vacuum source (not shown) such that at least a portion of the pressurized fluid and solvent dispensed by the fluid dispensing assembly1612from the nozzle1622passes through the gap1626and enter the vacuum passageway1624by flowing past the two posts1630. The flow path of the pressurized fluid and solvent is indicated by the arrow designated by reference numeral1628.

While certain aspects of the invention are depicted and associated with specific embodiments illustrated and described above, it should be apparent to those skilled in the art that aspects of one illustrated embodiment may be applied and suitable for use with other embodiments. For instance, any of the above embodiments may be adapted to include a microscope, a contact cleaning assembly, an evacuation system, interchangeable interface portions biased interface portions, multiple interface portions, use various solvents and pressurized fluids, have removable pressurized fluid and/or solvent containers, etc. Likewise, although the embodiments depicted and described above are shown as having certain aspects, it should be apparent that they may be operated suitably without certain described aspects, such as without a microscope, a contact cleaning assembly, an evacuation system, interchangeable interface portions, biased interface portions, multiple interface portions, removable pressurized fluid and/or solvent containers, etc.