Polishing pad assembly for fiber optic cable connector polishing apparatus

Information

  • Patent Grant
  • 6641472
  • Patent Number
    6,641,472
  • Date Filed
    Friday, April 27, 2001
    23 years ago
  • Date Issued
    Tuesday, November 4, 2003
    20 years ago
Abstract
An apparatus that mass polishes a variety of fiber optic cable connectors simultaneously. The apparatus includes a plurality of polishing plates, each capable of holding its own polishing film and pad, and having a varying height. The apparatus further includes a plurality of connector fixtures that may receive a variety of connectors at varying angles. Each connector fixture communicates with a corresponding polishing pad. Thus, fiber optic cable connectors having a variety of polished end faces may be provided with the apparatus. The apparatus also eliminates the potential for contamination among polishing films, reduces polishing steps, and saves labor and maintenance costs.
Description




BACKGROUND OF THE INVENTION




A. Field of the Invention




The present invention relates generally to the communications field, and, more particularly to a hybrid polishing apparatus for polishing fiber optic cable connectors and method of polishing the same.




B. Description of the Related Art




Interconnection devices are used to join a fiber optic cable to another fiber optic cable or a fiber optic component. The most common interconnection device is the connector. Types of fiber optic cable connectors are as various as the applications in which they are used. Different connector types have different characteristics, advantages, disadvantages, and performance parameters. However, all fiber optic cable connectors consist of the same four basic components.




The fiber optic cable mounts inside a first component called the ferrule. The ferrule is a long thin cylinder that is bored through the center at a diameter that is slightly larger than the diameter of the cladding of the fiber optic cable. The end of the fiber optic cable is located at the end of the ferrule. Ferrules are typically made of metal or ceramic, but may also be constructed of plastic.




A second component, the connector body or connector housing, holds the ferrule. The connector body is usually constructed of ceramic, metal, or plastic and includes one or more assembled pieces which hold the fiber optic cable in place. The details of connector body assemblies vary among connectors, but bonding and/or crimping is commonly used to attach strength members and cable jackets to the connector body. The ferrule extends past the connector body to slip in a coupling device, described below.




The third component, the cable, attaches to the connector body, and acts as a point of entry for the fiber optic cable. Typically, a strain-relief boot is added over the junction between the cable and the connector body to provide extra strength to the junction.




Most fiber optic connectors do not use the male-female configuration common to electronic connectors. Instead, a coupling device (the fourth component), such as an alignment sleeve, is used to mate the connectors.




High loss optical connections limit the length and quality of fiber systems. Reflections created at the fiber optic cable connector can travel back towards the light transmitter and disrupt laser modulation, resulting in signal distortion. The goal of all connectors is low light loss and minimal back reflection.




The primary factors affecting the loss and reflective characteristics of a fiber optic cable connector are the fiber coupling alignment, and the contour of surface geometry of the end face of the optical fiber. The fiber optic cable must be aligned in a coupling device with minimum lateral and angular misalignment for maximum light transmission. The surface fiber end face must be free of scratches and pits for minimum reflection. The curvature and angle of the fiber and the connector's ferrule end surfaces must be of a magnitude that ensures physical contact and minimal back reflectance.




The final step in the termination of a fiber optic cable connector onto an optical fiber is the polishing of the fiber end face. Originally, this procedure was manually accomplished. A connector was placed in a polishing fixture so that its ferrule was slightly protruding from the fixture base surface. The fixture was then repetitively moved across an abrasive polishing film which removed fiber material until the desired scratch-free surface was attained. This procedure was time consuming and sensitive to the operator's individual touch.




Machines have been developed to automate the polishing process. While providing obvious advantages over manual polishing, conventional polishing machines have significant shortcomings regarding various steps in the polishing process. Conventional polishing machines are dependent upon the fiber optic cable connector's interlocking hardware for mounting onto the polishing work fixture. This limits the usefulness of a single work fixture for multiple connector styles. Currently, there are a multitude of connector styles, including SMA connectors, ST connectors, biconic connectors, FC connectors, D


4


connectors, HMS-10 connectors (also known as Diamond connectors), SC connectors, LC connectors, fiber distributed data interface (FDDI) connectors, ESCON connectors, and EC/RACE connectors.




Increased labor and maintenance costs have necessitated a reduction in the time required to polish a fiber optic connector. The conventional polishing procedure involves multiple steps including the polishing of connectors on several types of polishing films. Minimizing these steps can greatly save time in the polishing operation.




Depending upon the application, some connectors require the fiber end face to be polished with a flat surface, other connectors require the fiber end face to be polished with an angled flat surface (preferably six-degree and eight-degree angles), while other connectors require the fiber end face to be polished with a conical end face. Moreover, the ferrules used in different connectors have different hardnesses. Thus, different connectors need to be polished at different angles with polishing surfaces and films having different hardnesses.




Conventional polishing machines use a single polishing surface and film, and thus, can only polish one type of connector at a time. Since different fiber optic cable connectors require fiber contact with different grits of polishing films and polishing surfaces, a machine with a single polishing surface and film will require the operator to change these surfaces and films several times during the complete process. Connectors having angled and conical fiber end faces further complicate the procedure because angled fixtures and different polishing pad hardnesses are required.




Using a single polishing pad and a variety of polishing films creates the potential for contamination from one connector type to another connector type. If the polishing film for one connector type contaminates the polishing pad (i.e., the pad is not sufficiently cleaned between connector polishing operations), there exists the potential for scratching a fiber end face of a connector. This is particularly true if the polishing film used for a connector having a ferrule with a hard material contaminates the polishing film used for connector having a ferrule with a softer material.




Furthermore, during a polishing operation, typically the connector moves on or traces a polishing pad in a pattern so that the connector never moves across the same portion of the polishing pad. Occasionally, however, a connector traverses over the same portion of the polishing pad. When this occurs, a connector trace overlap occurs. If connector trace overlap occurs, particulates of the hard connector ferrule may contaminate or mix with the polishing film or slurry and potentially scratch the relatively softer fiber end face.




Certain applications require a variety of fiber optic cable connectors to be used with a specific piece of fiber optic communications equipment. It is desirous to polish a complete set of connectors for a specific piece of fiber optic communications equipment with a single polishing apparatus. Unfortunately, with conventional polishing machines, an operator would have to polish a batch of one type of connector used in the set, and then change the polishing surface and film for the other connector types to be polished. Such a procedure is costly, time consuming, and may result in cross-contamination of polishing films between connectors.




Thus, there is a need in the art to for a polishing apparatus and method that polishes a variety of fiber optic cable connectors, having a variety of fiber end faces, eliminates the potential for contamination, reduces polishing process steps, and saves labor and maintenance costs.




SUMMARY OF THE INVENTION




The present invention solves the problems of the related art by providing an apparatus and method that polishes a variety of fiber optic cable connectors simultaneously. The apparatus of the present invention provides a plurality of polishing plates, each capable of holding its own polishing film and pad and having a varying height. The apparatus further provides a plurality of connector fixtures that may receive a variety of connectors at varying angles. Each connector fixture communicates with a corresponding polishing pad or section(s) thereof. Thus, fiber optic cable connectors having a variety of polished end faces may be provided with the apparatus of the present invention. The method of the present invention includes a plurality of steps for mass polishing of fiber optic cable connectors with varying patterns and loci of motion to substantially prevent overlap of polishing patterns during polishing (connector trace overlap). The apparatus and method of the present invention further eliminate the potential for contamination among polishing films, reduce polishing steps, and save labor and maintenance costs.




In accordance with the purpose of the invention, as embodied and broadly described herein, the invention comprises a polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, including: a plurality of wedges, each wedge aligning with a corresponding fiber optic cable connector held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedges.




Further in accordance with the purpose of the invention, as embodied and broadly described herein, the invention comprises a polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, including: a plurality of wedge pairs, each wedge aligning with a corresponding fiber optic cable connector held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedge pairs.




Still further in accordance with the purpose of the invention, as embodied and broadly described herein, the invention comprises a polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, including: a plurality of wedges, said wedges being arranged into a plurality of groups including a first group and a second group, wherein the first group of said wedges holds a plurality of a first type of polishing pad that aligns with corresponding fiber optic cable connectors held in the polishing fixture assembly, and the second group of said wedges holds a plurality of a second type of polishing pad that aligns with corresponding fiber optic cable connectors held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedges.




Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.











BRIEF DESCRIPTION OF THE DRAWINGS




The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein:





FIG. 1

is an exploded perspective view of a polishing fixture assembly and a polishing pad assembly for mass polishing of fiber optic cable connectors in accordance with an embodiment of the present invention;





FIG. 2

is an exploded side elevational view of the polishing fixture assembly and the polishing pad assembly shown in

FIG. 1

;





FIG. 3

is top elevational view of the polishing fixture and pad assemblies shown in

FIG. 1

, and showing three different pairs of clamps for holding fiber optic cable connectors;





FIG. 4

is cross-sectional view in elevation taken along line


4





4


of

FIG. 3

;





FIG. 5

is a schematic elevational view showing a fiber optic cable connector held perpendicular to a polishing pad shown in

FIG. 1

;





FIG. 6

is a schematic elevational view showing a fiber optic cable connector held at an angle to a polishing pad shown in

FIG. 1

;





FIG. 7

is a fragmental view of a ground fiber optic cable connector end face that has been polished on a hard or nonresilient polishing pad shown in

FIG. 1

;





FIG. 8

is a fragmental view of a ground fiber optic cable connector end face that has been polished on a resilient polishing pad shown in

FIG. 1

;





FIG. 9

is a top plan view of a polishing pad shown in FIG.


1


and showing an inventive locus of motion to polish the fiber optic cable connectors;





FIG. 10

is a top plan view of a polishing pad shown in FIG.


1


and showing an alternative inventive locus of motion to polish the fiber optic cable connectors;





FIG. 11

is a flow chart showing a method for mass polishing of fiber optic cable connectors in accordance with an embodiment of the present invention; and





FIG. 12

is a flow chart showing an alternative method for mass polishing of fiber optic cable connectors in accordance with an embodiment of the present invention.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




The following detailed description of the invention refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. Also, the following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims and equivalents thereof.




Referring now specifically to the drawings, a hybrid fiber optic cable connector polishing apparatus according to the present invention is illustrated in

FIG. 1

, and shown generally as reference numeral


10


. Hybrid polishing apparatus


10


includes a polishing fixture assembly


100


, a polishing pad assembly


200


, and a base


300


. Polishing fixture assembly


100


has a connector hub


102


that interconnects with a plurality of segment pairs that receive and hold a variety of fiber optic cable connector types. A first pair of segments


104


receive and hold a first fiber optic cable connector type


12


, a second pair of segments


104


′ receive and hold a second fiber optic cable connector type


14


, and a third pair of segments


104


″ receive and hold a third fiber optic cable connector type


16


.




Polishing pad assembly


200


includes a plurality of wedge pairs that align with a corresponding segment pair of polishing fixture assembly


100


. Each wedge may have a polishing pad


204


mounted thereon via conventional mounting means. Alternatively, a wedge may not have a polishing pad, and thus itself may be used as the polishing pad. Although each polishing pad


204


is shown as being circular, polishing pads


204


may have different shapes, including but not limited to elliptical, square, rectangular, or the same shape as its corresponding wedge.




A first pair of wedges


202


align with first pair of segments


104


, a second pair of wedge


202


′ align with second pair of segments


104


′, and a third pair of wedges


202


″ align with third pair of segments


104


″. As shown in

FIG. 1

, each wedge pair may have a different thickness, although the thicknesses of wedges


202


are exaggerated in FIG.


1


. For example, wedges


202


are thicker than wedges


202


′, which are thicker than wedges


202


″. Since polishing fixture assembly


100


is provided a uniform distance above polishing pad assembly


200


, the thicker the wedge, the greater the force applied to the polishing pad


204


provided on the wedge. The thickness of the wedges may also depend upon the material, the shape of the ferrules, the configuration of the connectors to be polished thereon, whether a polishing pad


204


is used, and/or whether other polishing media are used.




Each wedge


202


,


202


′,


202


″, may have a pair of holes


206


that align with holes


302


provided in base


300


for provision of a connecting means therethrough that connects wedges


202


,


202


′,


202


″ to base


300


. Connecting means may be any conventional type of connection means, including but not limited to screws, nuts and bolts, and pins.




Although pairs of segments and wedges are shown in

FIG. 1

, the hybrid polisher apparatus of the present invention may have distinct wedges and segments, and thus polish a greater number of distinct fiber optic cable connector types than segment/wedge pairing allows. Furthermore, the hybrid polishing apparatus of the present invention shown in

FIG. 1

includes six wedges, polishing pads, and segments, but may include more or less wedges, polishing pads, and segments. Preferably, hybrid polishing apparatus


10


has at least two wedges, two polishing pads, and two segments. The upper limit of wedges, pads, and segments should not effect the polishing capabilities of apparatus


10


. For example, the upper limit should not be so great that the polishing pads are too small to effectively polish the fiber optic cable connectors. Of course, increasing the size of hybrid polishing apparatus


10


would increase the number of wedges, segments, polishing pads, and connectors that may be used with the present invention.





FIG. 2

is an exploded side elevational view of hybrid polishing apparatus


10


shown in FIG.


1


. As shown, fiber optic cables


18


connect to first connector types


12


, and are housed by ferrules


22


that extend through connector


12


and segments


104


. Fiber optic cables


18


connect to third connector types


16


, and are housed by ferrules


20


that extend through connectors


16


and segments


104


″. Although not clearly shown, fiber optic cables


18


also connect to second connector types


14


, and are housed by ferrules (similar to ferrules


20


,


22


) that extend through connectors


14


and segments


104


″.




As best shown in

FIGS. 5 and 6

, a polishing film


214


may be provided on polishing pads


204


. Polishing film


214


may be any conventional polishing film used to polish fiber optic cable connectors. Polishing film


214


is selected to match the connector being polished. A conventional polishing slurry


208


may also be provided on polishing film


214


or may be used instead of polishing film


214


.





FIG. 3

is a top elevational view of hybrid polishing apparatus


10


of the present invention. Each segment of polishing fixture assembly


100


includes a base portion


106


and a means for attaching a fiber optic cable connector to base portion


106


. The attaching means varies for each segment pair, since different connector types are attached to each segment pair. Each of the first pair of segments


104


includes a clamp


116


having an opening


118


provided therein and a means for fixing clamp


116


to base portion


106


. Fixing means


120


may be any conventional type of connection means, including but not limited to screws, nuts and bolts, and pins. Opening


118


receives and holds first fiber optic cable connector type


12


in clamp


116


. Base portion


106


also has an opening provided therein through which a portion of connector type


12


and its fiber optic cable


18


and ferrule extend. Opening


118


and opening in base portion


106


may be provided at a predetermined angle to the surface of polishing pad


204


so that the end face of fiber optic cable


18


and its ferrule may be polished at an angle. The predetermined angle is best shown in

FIG. 6

as reference numeral A, and may be any angle depending upon the application to be used with the connector. Preferably, predetermined angle A is six degrees for first fiber optic cable connector type


12


.




Each of the second pair of segments


104


′ includes a recess


112


having an opening


114


provided therein for receiving and holding second fiber optic cable connector type


14


. Base portion


106


also has an opening provided therein through which a portion of connector type


14


and its fiber optic cable


18


and ferrule extend. Opening


114


and opening in base portion


106


may be provided at predetermined angle A to the surface of polishing pad


204


so that the end face of fiber optic cable


18


and its ferrule may be polished at an angle. Although predetermined angle A may vary depending upon the application, predetermined angle A is preferably eight degrees for second fiber optic cable connector type


14


.




Each of the third pair of segments


104


″ includes a clamp


108


and screw


110


assembly that receives and holds a pair of third fiber optic cable connector types


16


against base portion


106


. Screws


110


may be rotated in one direction to engage connector types


16


against base portion


106


. A portion of the pair of connector types


16


and its fiber optic cable


18


and ferrule extend between clamp


108


and base portion


106


. Clamp


108


and base portion


106


may hold connector types


16


at predetermined angle A to the surface of polishing pad


204


so that the end face of fiber optic cable


18


and its ferrule may be polished at an angle. Although predetermined angle A may vary depending upon the application, predetermined angle A is preferably zero degrees for third fiber optic cable connector types


16


, i.e., connector types


16


are held perpendicular to the surface of polishing pad


204


.




As further shown in

FIG. 3

, a cap


124


is affixed to connector hub


102


via pair of screws


126


. Cap


124


has a hole


122


provided therein for receiving a mounting fixture that holds polishing fixture assembly


100


fixed and at a predetermined height from the polishing pad assembly


200


.





FIG. 4

is cross-sectional view in elevation of hybrid polishing apparatus


10


, taken along line


4





4


of FIG.


3


. As shown, a mounting fixture


128


is provided above polishing fixture assembly


100


and has a shaft


130


extending therefrom. Shaft


130


extends through hole


122


of cap


124


and an opening provided at the center of connector hub


102


. Mounting fixture


128


and shaft


130


hold polishing fixture assembly


100


fixed against polishing pad assembly


200


until a desired pressure between the two is achieved.




As further shown in

FIG. 4

, the polishing pads may be made of a nonresilient (e.g., hard) material


210


such as glass, ceramic, or the like, or a resilient (e.g., soft) material


212


such as rubber (natural and synthetic), thermoplastic, or the like. Hard and resilient polishing pads


210


,


212


provide different end face geometries to fiber optic cable


18


, as described below. Although hard polishing pad


210


is shown being provided on thick wedges


202


, and resilient polishing pad


212


is shown being provided on thin wedges


202


″, either type of polishing pad


210


,


212


may be provided on any type of wedge


202


,


202


′, and


202


″.




As further shown in

FIG. 4

, X-Y stage


302


is attached to base


300


on one side, and an Y-motor


306


and an X-motor


308


on its other side. X-Y stage


302


, via X-motor


306


and Y-motor


308


, move base


300


and polishing pad assembly


200


in a predetermined pattern relative to the stationary polishing fixture assembly


100


, as described more fully below. X-motor


306


moves X-Y stage


302


back and forth in an x-direction, and Y-motor


308


moves X-Y stage


302


back and forth in a y-direction (perpendicular to the x-direction), in response to control signals provided by a conventional controller


310


, such as a programmable logic controller (PLC), a general purpose personal computer programmed with control software, etc.




Although a polishing pad assembly


200


having wedges


202


is preferable, polishing pad assembly


200


may also be made from of a singular disk that holds the polishing pads


204


. Such a disk would have a plurality of sections, with each section holding a corresponding polishing pad


204


. The thickness of each section of the singular disk may be varied, similar to the way the thicknesses of wedges


202


are varied. Furthermore, as may be the case with wedges


202


, the sections of the singular disk need not have polishing pads


204


. Instead, each section of the singular disk may function as a polishing pad.




Also, a single polishing pad


204


may be laid on singular disk pad assembly


200


. Wedge-shaped areas may be delineated by an embossed polishing film laid directly on base


300


or assembly


200


.





FIG. 5

is a schematic elevational view showing fiber optic cable


18


and ferrule


20


held perpendicular to hard polishing pad


210


provided on wedge


202


. Polishing film


214


is provided on a top surface of hard polishing pad


210


, and polishing slurry


208


may be provided on polishing film


214


. The combination of hard polishing pad


210


and polishing medium or media (e.g., polishing film


214


and polishing slurry


208


) provides a smooth flat end face


22


to fiber optic cable


18


and ferrule


20


, as shown in FIG.


7


. If fiber optic cable


18


and ferrule


20


are held at predetermined angle A (as shown in

FIG. 6

) to the surface of hard polishing pad


210


, an angled flat end face


24


is provided in fiber optic cable


18


and ferrule


20


, as shown in phantom in FIG.


7


. If hard polishing pad


210


is replaced with resilient polishing pad


212


(shown in

FIG. 6

) and fiber optic cable


18


and ferrule


20


are held perpendicular to resilient polishing pad


212


, the combination of resilient polishing pad


212


and polishing medium or media (e.g., polishing film


214


and polishing slurry


208


) provides a conical end face


22


to fiber optic cable


18


and ferrule


20


, as shown in FIG.


8


.





FIG. 9

is a top plan view of one of the polishing pads


204


shown in FIG.


1


and showing each of the pads


204


moving in a figure eight pattern


28


to polish the end faces of a fiber optic cables


18


and ferrules


20


of fiber connectors


12


,


14


,


16


. Each of the polishing pads


204


will simultaneously move in the figure eight pattern


28


shown in FIG.


9


through movement of the X-Y stage


302


, while fiber connectors


12


,


14


,


16


are maintained stationary by polishing fixture assembly


100


. The loci of motion of figure eight patterns


28


may also rotate in increments to prevent overlap of one figure eight pattern over another figure eight pattern, and substantially prevent connector trace overlap. Preferably, the loci of motion rotate in increments until figure eight patterns


28


have rotated almost one-hundred and eighty degrees, but may rotate less than this if the polishing process is complete. The incremental rotation of figure eight patterns


28


may vary, but preferably is sufficient to prevent connector trace overlap.




The background mentions a common connector trace overlap problem recognized in the art in which particulates of a connector ferrule left on a polishing film can scratch the relatively softer fiber end face if the fiber end face traces over these particulates.




Because the invention seeks to solve the problem of polishing different types of connectors having different hardnesses, the invention faces a different and more serious connector trace overlap problem. Namely, when a hard (e.g. ceramic) connector is polished it will leave behind a connector trace. These hard particles will scratch a relatively softer connector (e.g. plastic) if the soft connector polishing trace overlaps the hard connector polishing trace. Thus, if one simply tries to load different connector types having different hardnesses into a polisher and uses conventional loci of motion then the fiber end face and ferrule may be scratched due to connector trace overlap. This problem is solved by the inventive loci of motion.





FIG. 10

is a top plan view of one of the polishing pads


204


shown in FIG.


1


and showing each of the pads


204


moving in an elliptical pattern


30


to polish the end faces of fiber optic cables


18


and ferrules


20


of fiber connectors


12


,


14


,


16


. Each of the polishing pads


204


will simultaneously move in the elliptical pattern


30


shown in FIG.


10


through movement of the X-Y stage


302


, while fiber connectors


12


,


14


,


16


are maintained stationary by polishing fixture assembly


100


. The loci of motion of elliptical patterns


30


may also rotate in increments to prevent overlap of one elliptical pattern over another elliptical pattern. Preferably, the loci of motion rotate in increments until elliptical patterns


30


have rotated almost one-hundred and eighty degrees, but may rotate less than this if the polishing process is complete. The incremental rotation of elliptical patterns


30


may vary, but preferably is sufficient to prevent connector trace overlap.




Although

FIGS. 9 and 10

show two polishing patterns, the present invention may be used with a variety of conventional of future-developed polishing patterns. For example, a spirographic pattern may be achieved with the present invention. Any such polishing pattern may be adapted to the invention by tracing the pattern within the wedge-shaped area (e.g., defined by the individual segments or wedges or embossed film).




Polishing apparatus


10


may be used in a method of simultaneously polishing a plurality of fiber optic cable connectors


12


,


14


,


16


, in accordance with an embodiment of the present invention. Such a method would involve securing the plurality of connectors in a segment


104


of polishing fixture assembly


100


. A relative motion may then be imparted between polishing fixture assembly


100


and the base


300


of the polishing apparatus


10


. The relative motion is controlled so that each of the fiber optic cable connectors remains in its respective wedge-shaped area defined by wedge


202


. The relative motion may be a predetermined pattern, such as figure eight pattern


28


or elliptical pattern


30


shown in

FIGS. 9 and 10

. The predetermined pattern may also be a rotating locus of motion rotating within each of the wedge-shaped areas defined by wedge


202


.





FIG. 11

is a flow chart showing a method for mass polishing of fiber optic cable connectors using hybrid polishing apparatus


10


of the present invention. The method shown in

FIG. 11

may be used to polish fiber optic cable connectors in predetermined patterns, such as the figure eight patterns


28


shown in

FIG. 9

or the elliptical patterns


30


shown in

FIG. 10

, as well as the other patterns discussed above. In a first step


400


the method begins, and is followed by a second step


402


wherein a plurality of diverse fiber optic cable connectors are secured in hybrid polishing apparatus


10


having polishing pad assembly


200


. In a next step


404


, the polishing pad assembly


200


is moved so the connectors move in predetermined patterns on their corresponding polishing pads


204


. Subsequently, in step


406


, polishing pad assembly


200


is moved to rotate the loci of motion of the predetermined patterns and prevent overlap of patterns. In step


408


, there is check to see if the loci of motion of the patterns have rotated a predetermined amount (e.g., less than one-hundred and eighty degrees) or if polishing is complete. If the loci of motion has rotated the predetermined amount or polishing is complete, then the method is stopped at step


410


, otherwise step


406


is repeated and polishing pad assembly


200


is moved once again.




The method shown in FIG.


11


and the loci of motion shown in

FIGS. 9 and 10

are alone sufficient to polish diverse connector types without all of the elements of the hybrid polishing apparatus


10


described herein. A conventional polishing apparatus with polishing fixture assembly


100


or equivalent fixture controlled by the inventive methods or loci of motion is sufficient to prevent connector trace overlap of diverse connector types.




An alternative method for polishing fiber optic cable connectors may include the steps delineated above in

FIG. 11

, but may further include additional steps as set forth in FIG.


12


. First, alternating polishing pads


204


(or wedges


202


if pads


204


are not used) may have different polishing media (e.g., polishing film


214


and/or polishing slurry


208


). The polishing media may have different abrasivities, e.g., coarse, medium, or fine, as those terms are understood in the polishing art. Thus, a polishing pad having one media (coarse, medium, or fine) may be adjacent to two polishing pads having a different media, or a pad having one media may be adjacent to two dummy wedges. Dummy wedges may not have a polishing pad and should not impart a polish on connectors.




Different combinations of polishing media may be used. For example, assuming six polishing pads


204


are provided: (1) alternating coarse and fine polishing media may be provided; (2) alternating coarse and medium polishing media may be provided; (3) alternating medium and fine polishing media may be provided; (4) coarse, medium, fine, coarse, medium, and fine media may be provided; as well as other combinations.




The alternative method simultaneously polishes a plurality of fiber optic cable connectors


12


,


14


,


16


in polishing apparatus


10


. After securing the connectors in polishing fixture assembly


100


, alternative polishing media of different abrasivity are applied to wedges


202


. A relative motion may then be imparted between polishing fixture assembly


100


and the base


300


of the polishing apparatus


10


. The relative motion is controlled so that each of the fiber optic cable connectors remains in its respective wedge-shaped area defined by wedge


202


. The relative motion may be a predetermined pattern, such as figure eight pattern


28


or elliptical pattern


30


shown in

FIGS. 9 and 10

. The predetermined pattern may also be a rotating locus of motion rotating within each of the wedge-shaped areas defined by wedge


202


.




More specifically, as shown in

FIG. 12

, the alternative method begins at step


500


, and is followed by step


502


where a plurality of diverse connectors are secured on a hybrid polishing apparatus having a polishing pad assembly with alternating polishing pads of different polishing media. At step


504


, the polishing pad assembly is moved so that the connectors will move in predetermined patterns on their corresponding polishing pads, while the loci of motion of the patterns are rotated. Step


506


checks to see if polishing is complete. If polishing is complete, the process is terminated at step


512


, otherwise step


508


is performed and polishing pad assembly


200


is rotated so that the connectors previously provided over one polishing pad (or dummy wedge), may be provided over its adjacent polishing pad (or dummy wedge). Step


510


checks to see if polishing is complete. If polishing is complete, the process is terminates, otherwise the method returns to step


504


.




This way a connector may be: (1) polished with coarse polishing medium and then with medium or fine polishing media, and vice versa; (2) polished with a coarse polishing medium, then a medium polishing medium, and then with a fine polishing medium, or any combination of the three polishing media; (3) polished with a coarse, medium, or fine polishing medium, and then not polished by a dummy wedge; or (4) not polished by a dummy wedge, and then polished with a coarse, medium, or fine polishing medium.




The combinations of polishing media is dependent upon the number of wedges of apparatus


10


, as well as the number of connectors loaded into the polishing fixture assembly. For example, if one connector or connector set is provided and aligned over one wedge and there are six wedges provided, then the connector or connector set may be polished in two to six steps as the polishing pad assembly rotates to align two, three, four, five or six wedges with the connector or connector types. If a connector or connector set is aligned over two wedges and there are six wedges provided, then connector or connector set may be polished in two to three steps as polishing pad assembly rotates to align first, second, and third pairs of wedges with the connector pairs or connector set pairs.




The removable nature of the wedges of polishing pad assembly


200


and the segments of polishing fixture assembly


100


, enables a large variety of combinations of wedges and segments. The different types of polishing pads, films, and slurries further increases the variety of combinations. A few of the combinations will be discussed herein, but other combinations are possible with the present invention.




For example, each of the pairs of wedges, segments, and pads shown in the Figs. shows each wedge, segment, or pad of the pair being adjacent to one another. However, the pairings of wedges, segments, and pads need not be adjacent to another. They may also be nonadjacent, such as opposite to one another or have another wedge, segment, or pad between them. Furthermore, there need not be wedge, segment or pad pairs, but rather, six distinct wedges, segments, and pads may be provided. The wedges, segments, and pads may be grouped in a variety of ways, for example, there may be: (1) a first group having one wedge and one segment and one pad of one type, and a second group having five wedges and five segments and five pads of a different type; (2) a first group having two wedges and two segments and two pads of one type, and a second group having four wedges and four segments and four pads of a different type; (3) a first group having three wedges and three segments and three pads of one type, and a second group having three wedges and three segments and three pads of a different type; and (4) a first group having two wedges and two segments and two pads of one type, a second group having two wedges and two segments and two pads of another type, and third group having two wedges and two segments and two pads of still another type. Such groupings are based on the assumption that there are six wedges, segments, and pads, but may vary since, as noted above, the polishing apparatus is not limited to six wedges, segments, or pads.




Finally, the wedges and segments need not be of equal dimensions. For example, a wedge may be the same size as two wedges


202


combined, and hold two polishing pads


204


thereon, or a wedge may be the same size as three wedges


202


combined, and hold three polishing pads


204


thereon. The same holds true for the segments.




It will be apparent to those skilled in the art that various modifications and variations can be made in the hybrid fiber optic cable connector polishing apparatus and method of the present invention and in construction of the apparatus and method without departing from the scope or spirit of the invention. For example, although polishing fixture assembly


100


is shown as being stationary, and polishing pad assembly


200


is shown as moving in the Figs., polishing fixture assembly


100


may be moveable, and polishing pad assembly


200


may be stationary. Other examples of other modifications and variations to the present invention have been previously provided.




Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.



Claims
  • 1. A polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, comprising:a plurality of wedges, each wedge aligning with a corresponding fiber optic cable connector held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedges, wherein at least one of said plurality of wedges is thicker or thinner than the other said plurality of wedges.
  • 2. A polishing pad assembly as recited in claim 1, wherein each wedge holds a polishing pad.
  • 3. A polishing pad assembly as recited in claim 1, wherein said plurality of wedges comprises six wedges.
  • 4. A polishing pad assembly as recited in claim 3, wherein a first pair of said plurality of wedges are thicker than a second pair of said plurality of wedges, which is thicker than a third pair of said plurality of wedges.
  • 5. A polishing pad assembly as recited in claim 2, wherein at least one of the polishing pads comprises glass or ceramic.
  • 6. A polishing pad assembly as recited in claim 2, wherein at least one of the polishing pads comprises natural or synthetic rubber.
  • 7. A polishing pad assembly as recited in claim 2, wherein at least one of the polishing pads comprises a nonresilient material.
  • 8. A polishing pad assembly as recited in claim 2, wherein at least one of the polishing pads comprises a resilient material.
  • 9. A polishing pad assembly as recited in claim 2, wherein at least one of the polishing pads comprises a resilient material and at least one other of the polishing pad comprises a nonresilient material.
  • 10. A polishing pad assembly as recited in claim 1, further comprising means for moving said base in relation to the polishing fixture assembly.
  • 11. A polishing pad assembly as recited in claim 10, said moving means moves said base and the polishing pads provided on each of said plurality of wedges in a predetermined pattern in relation to the polishing fixture assembly.
  • 12. A polishing pad assembly as recited in claim 11, wherein the predetermined pattern is a rotating locus of motion rotating within each of said wedges.
  • 13. A polishing pad assembly as recited in claim 11, wherein the predetermined pattern is a figure eight with a rotating locus of motion.
  • 14. A polishing pad assembly as recited in claim 11, wherein the predetermined pattern is elliptical with a rotating locus of motion.
  • 15. A polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, comprising:a plurality of wedge pairs, each wedge aligning with a corresponding fiber optic cable connector held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedge pairs, wherein the wedges of each wedge pair are adjacent to each other.
  • 16. A polishing pad assembly as recited in claim 15, wherein each wedge holds a polishing pad.
  • 17. A polishing pad assembly as recited in claim 15, further comprising means for moving said base in relation to the polishing fixture assembly.
  • 18. A polishing pad assembly as recited in claim 17, said moving means moves said base and the polishing pads provided on each wedge in a predetermined pattern in relation to the polishing fixture assembly.
  • 19. A polishing pad assembly as recited in claim 18, wherein the predetermined pattern is a rotating locus of motion rotating within each of said wedges.
  • 20. A polishing pad assembly as recited in claim 18, wherein the predetermined pattern is a figure eight with a rotating locus of motion.
  • 21. A polishing pad assembly as recited in claim 18, wherein the predetermined pattern is elliptical with a rotating locus of motion.
  • 22. A polishing pad assembly as recited in claim 15, wherein at least one pair of said plurality of wedge pairs is thicker than the other said plurality of wedge pairs.
  • 23. A polishing pad assembly as recited in claim 15, wherein at least one pair of said plurality of wedge pairs is thinner than the other said plurality of wedge pairs.
  • 24. A polishing pad assembly as recited in claim 15, wherein said plurality of wedge pairs comprises three wedge pairs.
  • 25. A polishing pad assembly as recited in claim 24, wherein a first pair of said plurality of wedge pairs are thicker than a second pair of said plurality of wedge pairs, which is thicker than a third pair of said plurality of wedge pairs.
  • 26. A polishing pad assembly as recited in claim 16, wherein at least one of the polishing pads comprises glass or ceramic.
  • 27. A polishing pad assembly as recited in claim 16, wherein at least one of the polishing pads comprises natural or synthetic rubber.
  • 28. A polishing pad assembly as recited in claim 16, wherein at least one of the polishing pads comprises a nonresilient material.
  • 29. A polishing pad assembly as recited in claim 16, wherein at least one of the polishing pads comprises a resilient material.
  • 30. A polishing pad assembly as recited in claim 16, wherein at least one of the polishing pads comprises a nonresilient material, and at least one other of the polishing pads comprises a resilient material.
  • 31. A polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, comprising:a plurality of wedge pairs, each wedge aligning with a corresponding fiber optic cable connector held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedge pairs, wherein the wedges of each wedge pair are nonadjacent to each other.
  • 32. A polishing pad assembly for a fiber optic cable connector polishing apparatus having a polishing fixture assembly for holding a plurality of different types of fiber optic cable connectors, comprising:a plurality of wedges, said wedges being arranged into a plurality of groups including a first group and a second group, wherein the first group of said wedges holds a plurality of a first type of polishing pad that aligns with corresponding fiber optic cable connectors held in the polishing fixture assembly, and the second group of said wedges holds a plurality of a second type of polishing pad that aligns with corresponding fiber optic cable connectors held in the polishing fixture assembly; and a base interconnecting with each of said plurality of wedges.
  • 33. A polishing pad assembly as recited in claim 31, wherein each of the first and second groups of said wedges comprises three wedges.
  • 34. A polishing pad assembly as recited in claim 31, wherein the first group of said wedges comprises two of said wedges, and the second group of said wedges comprises four of said wedges.
  • 35. A polishing pad assembly as recited in claim 31, wherein the plurality of groups includes a third group of said wedges that holds a plurality of a third type of polishing pad that aligns with corresponding fiber optic cable connectors held in the polishing fixture assembly.
  • 36. A polishing pad assembly as recited in claim 35, wherein each of the first, second, and third groups of said wedges comprises three wedges.
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