US20220410334A1

US20220410334A1 - Method and assembly for polishing optical cables

Info

Publication number: US20220410334A1
Application number: US17/801,500
Authority: US
Inventors: Ray Pierce
Original assignee: Precision Fiber Products Inc
Current assignee: Precision Fiber Products Inc
Priority date: 2020-03-04
Filing date: 2021-03-03
Publication date: 2022-12-29
Also published as: WO2021178584A1

Abstract

A polishing assembly and method for polishing optical cables, the polishing assembly having a platform configured to receive a polishing film and configured to rotate according to a dual orbital motion; a force gauge functionally coupled to the platform and configured to measure downward force applied against the platform; a mounting fixture configured to mount a plurality of optical cables; and a movable arm configured to move the mounting fixture downwards to press mounted cables against the polishing film, upwards to pull the mounted cables away from the polishing film, and to rotate circularly along a continuous circular path. The optical cables are pressed against the rotating polishing film while simultaneously monitoring the downward force applied against the platform so that downward force can be maintained within a prescribed tolerance throughout the polishing process.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims benefit of priority to U.S. patent application No. 62/985,172, filed Mar. 4, 2020, the content of which is herein incorporated by reference in its entirety.

TECHNICAL FIELD

The invention relates to methods and assemblies for polishing optical cables.

BACKGROUND OF THE INVENTION

Fiber optic cables are cables that contain several thousand optical fibers in a protective insulated jacket. These optical fibers are very thin strands of silica (e.g., glass) that transmit information in the form of light. Fiber optic cables are increasingly used in industries such as telecommunications, medical diagnostics, medical therapeutics (e.g. surgery and dentistry), automotive, lighting, mechanical inspection and analytical instrumentation, military, and aerospace.
Fiber optic cables are polished after cleaving to remove scratches and other surface imperfections that promote signal loss. Typically, fiber optic cable polishers include a cable mount and a rotating polishing film that presses and rubs against the cable. Among the important factors for consideration to achieve high precision polishing include the speed of the rotating film, the positioning of the cable and its applied pressure against the rotating film, and the duration of polishing.

BRIEF SUMMARY OF THE INVENTION

The invention provides improved methods, assemblies and devices for high precision polishing, which can be adjusted in a reactive manner due to inputs in real time from physical force data. This is achieved in one aspect of the invention by a method of polishing optical cables, which includes a polishing assembly loaded with a polishing film, the polishing assembly having a platform to which the polishing film is loaded, the platform configured to rotate according to a dual orbital motion and coupled to a force gauge that measures downward force applied against the platform, a mounting fixture configured to mount a plurality of optical cables, the mounting fixture attached to a movable arm that moves the mounting fixture towards and away from the platform. The method includes mounting a plurality of optical cables to the mounting fixture; pressing the optical cables against the rotating polishing film while simultaneously monitoring the downward force applied against the platform; and adjusting the downward force to remain within a prescribed tolerance.
In some embodiments, the fixture includes a plurality of clamps that clamp the plurality of optical cables in place. In further embodiments, the clamps include a moveable tab that locks closed using magnetic force.
In preferred embodiments, the fixture and platform are adjustably aligned parallel to one another, preferably by way of adjustment dials that adjust the fixture and platform. In some embodiments, the adjustment dials are 4-way adjustment dials.
The rotation speed of the platform preferably increases gradually. Likewise, the arm presses the cables against the rotating polishing film gradually to polish the cables at a lower pressure followed by polishing the cables at a higher pressure. The higher pressure can vary but is typically about 0.5-1 lb. of pressure per cable.
In preferred embodiments, the force gauge is in physical-force communication with the platform, thereby measuring pressure directly applied to the platform. This downward force can be adjusted by a feedback mechanism that functionally couples the force gauge to the arm.
The method can also include washing the polished optical cables in an ultrasonic bath, the bath optionally filled with deionized water and/or isopropyl alcohol. Moreover, the method can include optically inspecting a polished surface of the cables, and optionally repeating polishing and washing steps until the polished surface meets a final acceptable standard. During such a process a same or different polishing film can be used. The preferred approach for optical inspection includes inspection by camera. The camera may be configured to relay inspection footage to a computer, loaded with software that compares the polish to an intermediate or final standard. In some embodiments, the camera provides a live feed to a computer.
In a related aspect of the invention, a polishing assembly is provided, which includes a platform configured to receive a polishing film and configured to rotate according to a dual orbital motion; a force gauge functionally coupled to the platform and configured to measure downward force applied against the platform; a mounting fixture configured to mount a plurality of optical cables; and a movable arm configured to move the mounting fixture downwards to press mounted cables against the polishing film, upwards to pull the mounted cables away from the polishing film, and to rotate circularly along a continuous circular path.
The fixture can include a plurality of clamps that clamp the plurality of optical cables in place. The clamps can include a moveable tab that locks closed using magnetic force.
In some embodiments, the fixture and platform are adjustably aligned parallel to one another, preferably by way of adjustment dials that adjust the fixture and platform, the adjustment dials optionally being 4-way adjustment dials.
Preferably, the force gauge is in physical-force communication with the platform, thereby measuring pressure directly applied to the platform. The force gauge can communicate directly with the arm or with a computer that communicates with the arm.
The polishing assembly can also include or be used in connection with an ultrasonic bath, the bath optionally filled with deionized water and/or isopropyl alcohol. The polishing assembly can also include or be used in connection with an optical inspection station, which includes a camera. The camera can relay inspection footage to a computer, optionally loaded with software that compares the polish to an intermediate or final standard. In some embodiments, the camera provides a live feed to a computer.
In still another related aspect of the invention, a mounting fixture configured to mount a plurality of optical cables is provided, which includes a planar surface having a plurality of apertures for receiving a plurality of optical cables; a plurality of arms that rock open and closed to release and lock the cables in place; and a plurality of magnets that magnetically lock the arms closed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1C are pictorial diagrams showing a polishing assembly 10 in accordance with one or more embodiments of the present disclosure.

FIGS. 2A-2F are pictorial diagrams showing an exemplary process of mounting optic cables 70 to a mounting fixture 50 in accordance with one or more embodiments of the present disclosure.

FIG. 2E is a pictorial diagram showing a cross-sectional perspective view of an exemplary clamp 54 in an open position taken along line 2E-2E of FIG. 2C in accordance with one or more embodiments of the present disclosure.

FIG. 2F is a pictorial diagram showing a perspective view of the clamp 54 in the closed position in accordance with one or more embodiments of the present disclosure.

FIGS. 3A-3B are pictorial diagrams showing movement of an arm 16 and the fixture 50 towards a polishing film 80, which is positioned on the polishing platform 12 in accordance with one or more embodiments of the present disclosure.

FIG. 4 is a pictorial diagram showing an exemplary cable path 22 over the polishing film 80 or platform 12 during dual orbital rotation in accordance with one or more embodiments of the present disclosure.

FIG. 5 is a pictorial diagram showing an exemplary orbital gearing 24 to accomplish dual orbital rotation in accordance with one or more embodiments of the present disclosure.

FIG. 6 is a pictorial diagram showing an exemplary ball bearing 26 configuration for improved dual orbital rotation in accordance with one or more embodiments of the present disclosure.

FIG. 7 is a pictorial diagram showing a cross-sectional side view of the polishing assembly 10 along line 7-7 of FIG. 1A in accordance with one or more embodiments of the present disclosure.

FIG. 8 is a pictorial diagram showing an exemplary force gauge 20 in accordance with one or more embodiments of the present disclosure.

FIG. 9 is a pictorial diagram showing the force gauge 20 in accordance with one or more embodiments of the present disclosure.

FIGS. 10A-10C are pictorial diagrams showing an exemplary mounting fixture 50 in accordance with one or more embodiments of the present disclosure.

FIG. 10D is a pictorial diagram showing a cross-sectional perspective view of the exemplary mounting fixture 50 taken along line 10D-10D of FIG. 10B in accordance with one or more embodiments of the present disclosure.

FIG. 11 is a block diagram showing exemplary stations used during polishing and inspection processes of the polishing assembly 10 in accordance with one or more embodiments of the present disclosure.

FIG. 12 is a flow chart showing an exemplary process of the assembly of polishing and inspecting optic cables 70 in accordance with one or more embodiments of the present disclosure.

Embodiments of the present disclosure and their advantages are best understood by referring to the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with various embodiments herein, a polishing assembly and methods of polishing optical cables are disclosed here. More specifically, the polishing assembly may polish optical cables at a high precision, thereby, reducing signal loss when coupling ends of the optical cables to connectors or other devices.
In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustrative embodiments in which the inventions may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and mechanical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined only by the claims and equivalents thereof. For completeness, the invention is discussed with respect to an “optical cable”, which is intended to encompass a fiber optic strand and a group of fiber optic strands as known in the fiber optic industry. However, the polishing assembly will also have use with other industries, where a high-precision polish of a silica substrate is desired.
Referring now to the drawings, FIGS. 1A-1C show a polishing assembly 10 in accordance with one or more embodiments of the present disclosure. High-precision polishing is accomplished by way of a polishing assembly 10, which includes a base 48 and a mounting fixture 50 (also referred to herein as a “fixture”) selectively coupled to base 48. In one or more embodiments, base 48 may include a platform 12, an arm 16, and dial indicators 18. Base 48 may also include a body 28 having a housing 30 that platform 12 extends therefrom. In one or more embodiments, a motor 92 is disposed within housing 30 of body 28 (as shown in FIG. 7 ). In one or more embodiments, platform 12 is configured to receive and secure a polishing film 80 (shown in FIGS. 3A and 3B) and rotate about axis A of arm 16 (e.g., following a dual orbital motion). In one or more embodiments, a force gauge 20 is functionally coupled to platform 12 (shown in FIG. 7 ) and configured to measure a force (e.g., a downward force that is along axis A of arm 16 and toward platform 12) applied against platform 12. In one or more embodiments, mounting fixture 50 is configured to receive and mount a plurality of optical cables 70 (shown in FIGS. 2A and 2B), as discussed further herein. In one or more embodiments, movable arm 16 is configured to move in multiple directions manually (e.g., using dials 38) or automatically.
In one or more embodiments, arm 16 may move in one or more directions to achieve various positions relative to platform 12. In one or more embodiments, arm 16 may be moved to any desired position using, for example, dials 38. In one or more embodiments, arm 16 may move mounting fixture 50 towards platform 12 and corresponding polishing film 80 (shown in FIGS. 3A and 3B) to press mounted cables 70 (shown in FIGS. 2A and 2B) against polishing film 80. Similarly, arm 16 may move mounting fixture 50 away from polishing film 80. For example, arm 16 may be moved upward away from platform 12 and along axis A. Arm 16 also rotates circularly about axis B of base 48 along a continuous circular path, which can be used to incorporate supplemental steps and stations, such as those for washing, quality inspection, and collection/mounting of cables, as discussed further herein. Alternatively, or in addition, rotation permits the use of multiple movable arms 16 extending from a single axis (e.g., axis B) to polish multiple sets of optical cables 70, where each movable arm 16 moves in series through any number of polishing, washing, and inspection steps.
FIGS. 2A-2F show an exemplary process of mounting optic cables 70 to mounting fixture 50 in accordance with one or more embodiments of the present disclosure. As shown in FIGS. 2A and 2B, optical cables 70 are securely mounted to mounting fixture 50, which is itself attached or attachable to arm 16. For example, mounting fixture 50 may be selectively coupled to arm 16 by inserting a protrusion 68 of arm 16 within a bore 14 of stem of mounting fixture 50 and fastening protrusion 68 within bore 14 using various attachment mechanism such as, for example, screws (as shown in FIG. 1C). While it is within the scope of the disclosure that mounting fixture 50 mount only one or only a few cables 70, preferably, fixture 50 mounts a plurality of cables 70 to permit simultaneous and efficient polishing. In some embodiments, fixture 50 mounts at least thirty or about thirty cables 70. Cables 70 can be arranged according to a variety of patterns. For example, cables 70 may be equally spaced along a circular path about mounting fixture 50. More specifically, cables 70 may be positioned and mounted about a circumference of pad 46 so that each cable 70 along the circumference is equidistant to axis A when mounting fixture 50 is attached to arm 16.
By “mounted”, it is meant that cables 70 traverse mounting fixture 50 by passing through pad 46 and are held in place. For example, cables 70 traverse through an aperture 52 of pad 46 and are held in place such as by way of a clamp 54. In one or more embodiments, each clamp 54 may include at least a tab 56, a spring 60, and at least two magnets 58 (e.g., magnet 58 a of tab 56 and magnet 58 b of pad 46). In such embodiments, each clamp 54 has at least two positions, namely, an open position (shown in FIGS. 2A, 2C, 2D, and 2E) to permit cable 70 to slide in and out of aperture 52, and a closed position (shown in FIGS. 2B and 2F) that securely holds cable 70 in place during polishing, washing, and/or analysis.
Although there are different mechanisms available to the skilled artisan to reversibly clamp cables 70, FIGS. 2A-2F show a particularly preferred configuration, which uses magnetic attraction. In particular, a plurality of tabs 56 are shown that rock open and closed to either release or lock cables 70 in place, respectively. Furthermore, a plurality of magnets 58 are provided that magnetically hold rocking tabs 56 when in the closed position. For, example, a user may push tab 56 in a first direction (e.g., in a downward direction shown by directional arrow 11) toward pad 46 until magnet 58 a of tab 56 is abutting magnet 58 b of pad 46. The magnetic attraction between magnets 58 a,b results in clamp 54 maintaining the closed position by tab 56 continuously abutting pad 46 during operation of polishing assembly 10. The artisan will appreciate that different magnets 58 can be used to achieve the same affect, including ferrite, alnico, and rare earth magnets. Once magnetically closed, a holding force of clamp 54 can be facilitated by a flat spring 60, which presses against a boot 62, through which cable 70 passes. It has been found that magnetic attraction effectively maintains clamp 54 in a closed position and also provides an easy approach for releasing clamp 54 into the open position, namely, using one's finger to simply upwardly (e.g., in a direction opposite of directional arrow 11) flip a tongue portion 64 of tab 56, which extends over the edge of pad 46, to overcome the magnetic attraction between magnets 58 a,b. In one or more embodiments, the open position may also be facilitated by a coiled spring 72 disposed beneath tab 56 that keeps tab 56 in the open position unless a user applies a downward force, compressing coiled spring 72.
Turning to FIG. 3A and FIG. 3B, fixture 50 is attached or attachable to mechanical arm 16, and surface 82 fixture 50 is, preferably, aligned parallel to a surface 84 of platform 12. The precise adjustment of the plane (e.g., surface 82) of fixture 50 can be performed through the use of dial indicators 18 on arm 16 and/or fixture 50. In preferred embodiments, four dial indicators 18 are used to provide complete control over the attachment of fixture 50 to mechanical arm 16 to ensure a precise alignment of planar fixture 50. Since the parallel alignment between fixture 50 and polishing platform 12 is critical, in some embodiments, polishing platform 12 can be tilted, such as by dial indicators 18 to ensure parallel orientation with fixture 50.
FIGS. 3A and 3B show movement of arm 16 and fixture 50 towards polishing film 80 (e.g., as indicated by directional arrow 13 of FIG. 3A), which is positioned on polishing platform 12 in accordance with one or more embodiments of the present disclosure. In one or more embodiments, fixture 50 is lowered towards the polishing film-loaded platform 12 for polishing (cables omitted for demonstration purposes). Typically, as arm 16 moves towards polishing film 80, arm 16 slows as cables 70 (shown in FIG. 2B) reach polishing film 80. A slow movement of arm 16 slowly builds pressure between cables 70 and polishing film 80/platform 12. In one or more embodiments, polishing begins at a lower pressure, then the pressure is continued or increases over time during the polishing process. In an exemplary embodiment, when polishing a set of thirty cables 70, a typical force starts at about 0.5-1 lb, then increases up to about 20 lbs. In other embodiments, the force may be as high as 30 lbs. In one or more embodiments, the force applied to each cable 70 during polishing may be between 0.25-3 lbs. As will be discussed in more detail in the paragraphs that follow, force gauge 20 (shown in FIGS. 7-9 ) measures the force applied to platform 12, and a feedback mechanism communicatively coupled to force gauge 20 dictates movement of arm 16 to maintain the applied force within desired parameters. In one or more embodiments, platform 12 may have a high speed of 100 rpm.
FIG. 4 shows an exemplary cable path 22 over polishing film 80 during dual orbital rotation in accordance with one or more embodiments of the present disclosure. In one or more embodiments, polishing may be performed by a way of singular orbital rotation. In one or more embodiments, polishing is performed by way of dual orbital rotation of platform 12, which is overlaid with polishing film 80, such as a 3 μm-9 μm diamond film. In one or more embodiments, dual orbital cable path 22 includes two concentric paths including an outer path 32 and an inner path 34 (e.g., two concentric epitrochoid paths). Among the benefits of dual orbital rotation is that it prolongs the life of polishing film 80 because cable path 22 over film 80 does not repeat. In an exemplary embodiment, twenty cables 70 may be positioned along an outer circumference of pad 46, which follow outer path 32 during polishing, and ten cables 70 may be positioned along an inner circumference of pad 46, which follow inner path 34 during polishing.
FIGS. 5 and 6 show exemplary embodiments of orbital gearing 24 of platform 12 and a bearing 26 (e.g., a ball or roller bearing) of arm 16 used to accomplish the dual orbital rotation in accordance with one or more embodiments of the present disclosure. In one or more embodiments, orbital gearing 24 is located beneath surface 84 of platform 12 and allows for rotation and lateral movement of platform 12. In one or more embodiments, bearing 26 allows for rotation of arm 16 about axis B.
Proceeding to FIGS. 7-9 , in preferred embodiments, the force applied against platform 12 is preferably measured using force gauge 20, which is positioned underneath polishing platform 12 (shown in FIG. 7 ). In one or more embodiments, polishing assembly 10 also includes a strain gauge 96. In particular, positioning force gauge 20 in physical force communication with platform 12 directly measures forces applied to platform 12. The implication of this arrangement is that force gauge 20 receives true pressure and, thus, provides true force data. As such, there is no need to further calculate or extrapolate pressure using equations or conversions that would be required in electronic or optical detection systems.
In some embodiments, force gauge 20 communicates directly with electronic circuitry in arm 16 to instruct upward or downward movement of arm 16 to achieve a desired force. In other embodiments, force gauge 20 collects pressure readings and provides the data to a computer processing unit, which instructs movement of mechanical arm 16 and, optionally, rotational speed of polishing platform 12 in response to the provided pressure data. To this end, the dual orbital speed of polishing platform 12 and the contact force of cables 70/mounting fixture 50 can be adjusted in response to pressure data provided by force gauge 20. In other embodiments, force gauge 20 provides data to ensure surface 82 of mounting fixture 50 is level with surface 84 of platform 12 so that pressure is evenly applied to each cable 70. Furthermore, the computer processing unit may use an algorithm that compensates for nonlinearity and to prevent any undesired play or wiggle in arm 16 and mounting fixture 50 when not in use, which is often an inherent problem in stepper motors. In one or more embodiments, the computer processing unit may also determine the lifetime of polishing film 80. For example, a timer of the computer processing unit may count the number of polishing cycles, the time of each polishing cycle, and/or the pressure of each polishing cycle to determine when a user should replace polishing film 80. As understood by one skilled in the art, the computer processing unit may be any compatible electronic device (e.g., processor, smartphone, desktop computer, laptop, or tablet). In one or more embodiments, computer processing unit may be loaded with a software (e.g., an application). In one or more embodiments, computer processing unit may include an interface that allows for user input or display of collected or processed data.
The technical approach of coupling a force gauge 20 to the platform 12 rather than measuring an applied force through or at the arm 16 has many advantages. For example, a system that measures force at the arm 16 requires substantially more compensation in that the measurement would also have to consider the weight of the fixture 50, any connectors, optical cables 70 mounted to the fixture 50, and arm 16 itself. Furthermore, it would also have to compensate for the downward force being applied by the arm 16 itself during polishing.
As already introduced, the feedback mechanism controls the movement of arm 16 and, thus, the pressure applied from cables 70 against polishing platform 12. This feedback mechanism can be by directly communicating force gauge 20 to a regulator that regulates downward movement of arm 16. The regulator can be programmed to perform a stepwise progression through a preset array of pressures or can be adjusted manually by a user to perform a desired pressure. In other embodiments, force gauge 20 is communicatively coupled to a computer with programming able to receive the pressure data and, in response, adjust movement of fixture 50 towards polishing platform 12 to meet program requirements. Preferably, the computer is also communicatively coupled to motor 92 of polishing assembly 10 for controlling the speed of the dual orbital rotation of polishing platform 12 so that the rotational speed of polishing film 80 can progress according to real time measurements of the applied pressure.
FIGS. 10A-10D show another exemplary embodiment of mounting fixture 50 in accordance with one or more embodiments of the present disclosure. As previously mentioned herein, a dual orbital rotation may be used to polish cables 70. Accordingly, mounting fixture 50 may include an arrangement of cables 70 having two concentric circles. As shown in FIGS. 10A-10D, pad 46 may include an outer circular arrangement 172 of apertures 52 and an inner circular arrangement 174 of apertures 52, where each clamp 54 may be mounted over each aperture 52 to mount cables 70 to fixture 50.
In exemplary embodiments, cables 70 mounted within apertures 52 of outer arrangement 172 may follow along outer path 32 of cable path 22 during the polishing process, and cables 70 mounted within apertures 52 of inner arrangement 174 may simultaneously follow along inner path 34 of cable path 22 during the polishing process (shown in FIG. 4 ). In one or more embodiments, fixture 50 may also include outer bracket 142 and inner bracket 144. Cables 70 may abut portions of brackets 142,144 that are directly above corresponding apertures 52 to provide alignment of cables 70 and secure opposing ends of cables 70. In one or more embodiments, apertures 52 may be empty (as shown in FIG. 2E). In other embodiments, apertures 52 may have additional components disposed therein, such as a sleeve 188, which cable 70 may traverse therethrough, and a pair of opposing notches 192, which may further engage complementary surfaces of boot 62 to secure boot 62 to pad 46.
FIG. 11 is a block diagram showing polishing assembly in an exemplary use in accordance with one or more embodiments of the present disclosure. Polishing assembly 10 may be positioned at a polishing station 300. Polishing assembly 10 may be in communication with a computer processing unit (e.g., electronic device 302) via a communication link 308. Communication link 308 may be a wired or wireless communication. In one or more embodiments, electronic device 302 may include a display and/or interface, allowing a user to input commands to electronic device 302. Polishing assembly 10 may polish cables 70 at polishing station 300 using friction and by rubbing the ends of cables 70, which are secured in fixture 50, against polishing film 80, which is secured to platform 12.
In one or more embodiments, polishing assembly 10 includes or is used together with an ultrasonic bath (not shown). For example, arm 16 of polishing assembly 10 may pivot about axis B toward a washing station 310. Washing station 310 may include an ultrasonic bath 306. Ultrasonic baths are liquid baths that use cavitation bubbles induced by high frequency to agitate the liquid. This agitation produces high forces on contaminants adhering to substrates, such as optical cables 70. Accordingly, the method of polishing optical cables 70 can also include movement of arm 16 to move cables 70 away from platform 12, rotation towards ultrasonic bath 306, and lowering optical cables 70 into ultrasonic bath 306 to remove residual material away from optical cable 70. Though non-limiting, ultrasonic bath 306 can include deionized water, isopropyl alcohol, or any combinations thereof.
In one or more embodiments, polishing assembly 10 may also include or be used together with an inspection station 320. Inspection station 320 may include a camera 304, which is in communication with electronic device 302 via communication link 312. Communication link 312 may be a wired or wireless communication link. For example, wired communication may be but not limited to, Ethernet, DSL, or cable. Wireless communication may be, but not limited to, use Bluetooth or Wi-Fi. Inspection station 320 may be used to inspect the surfaces of cables 70 before, during, or after polishing station 300. In an exemplary embodiment, arm 16 may pivot about axis B to inspection station 320 so the finish of cables 70 made be inspected by means discussed further herein.
FIG. 12 is a flow chart showing an exemplary process 200 of polishing and inspecting cables 70 using polishing assembly 10 in accordance with one or more embodiments of the present disclosure. In some embodiments, polishing assembly 10 includes or is used together with a quality control inspection step to ensure cable 70 is polished within required tolerances or percentage of yield) (e.g., inspection station 320). In particular, cables 70 should be free of scratches and other surface imperfections that promote signal loss.
In block 202, after mounting cables 70 to fixture 50, a user or an automation may lower mounted cables 70 toward polishing platform 12, which is loaded with a polishing film 80, until cables 70 contact (e.g., are pressing against) polishing film 80 at a desired pressure. For example, arm 16 may be lowered using dials 38 and one or more linear slides so that attached mounting fixture 50 is, consequently, lowered toward platform 12, which has polishing film 80 secured thereto (e.g., secured to surface 84 of platform 12). Simultaneously, the process may include monitoring the downward force applied against platform 12 using force gauge 20.
In block 204, a user may begin the polishing process, allowing the process to proceed for a predetermined duration of time. As mentioned herein, the rotational speed of platform 12 may gradually increase once cables 70 are in contact with polishing film 80 to remove any imperfections on the surfaces of cables 70. In one or more embodiments, arm 16 may also increase pressure between cables 70 and platform 12 during the polishing process. Thus, the process may include adjusting the downward force to remain with a prescribed tolerance. In one or more embodiments, arm 16 may rotate fixture 50 about axis A. In one or more embodiments, the predetermined duration of time may be chosen by a user or may be determined, for example, by the computer processing unit.
In block 206, a user or computer processing unit (e.g., electronic device 302) may stop polishing so that the user or computer processing unit may analyze cables 70. For example, arm 16 may move fixture 50 over to inspection station 320 so that a user or electronic device 302 may analyze and determine the current status of the polish on each cable 70. For manual inspection, a user may do an optical inspection of cables 70 by referencing an exemplary image of a polished cable that is, for example, provided by electronic device 302, as shown in block 208. The user may then determine from the exemplary image whether or not cables 70 are within the desired tolerance or percentage of yield, as shown in block 212. For automated inspection, cables 70 may be scanned, for example, by camera 304, which is communicatively coupled to the electronic device 302 so that electronic device 302 may determine the tolerance or percentage of yield of each cable 70, as shown in block 210. For example, camera 304 may relay inspection footage to electronic device 302, which is, optionally, loaded with software that compares the polish of cables 70 to an intermediate or final standard. In one or more embodiments, camera 304 provides a live feed to electronic device 302, which may be shown on a display of electronic device 302. After inspecting cables 70, electronic device 302 may determine if the desired percentage of yield is achieved, as shown in block 212.
In one or more embodiments, inspection is performed after washing cables 70 in ultrasonic bath 306 by instructing arm 16 to move fixture 50 with cables 70 away from ultrasonic bath 306 at washing station 310 and continue the rotational path to inspection station 320, which itself may have one or more inspecting cameras, such as camera 304. Since polishing assembly 10 may use a stepper motor and at least one bearing (e.g., a roller bearing), mounting fixture 50 may be moved in any direction to any position necessary for proper inspection. For example, fixture 50 may rotate, pivot, or slide in any direction while camera 304 at inspection station 320 is scanning each cable 70. After scanning cables 70, electronic device 302 may provide data regarding the percentage of yield and, if applicable, the additional time required to achieve the desired percentage of yield.
In one or more embodiments, inspection can be performed by visual inspection under magnification, surface scattering approaches, or performed by a camera (e.g., camera 304) coupled to a computer or viewing monitor for surface analysis (e.g., electronic device 302), which eliminates any subjective aspect of inspection. As shown in block 212, inspection can result in a positive or negative response. A positive response demonstrates that the polished material is of suitable quality and, thus, passes inspection. A negative response demonstrates that the polished material is not of suitable quality and must be reworked.
If the user or computer processing unit determines the percentage of yield to be acceptable (e.g., within 90%), then cables may be removed from mounting fixture 50, as shown in block 214. If the user or computer processing unit determines, that the desired percentage of yield has not been achieved, then the process may return to block 202, continuing the polishing process until cables 70 are within the desired percentage of yield and are, thus, found to have an acceptable polish.
In an exemplary embodiment, upon a positive response, optionally, mechanical arm 16 can move fixture 50 away from the inspection station 320 to a collection station (not shown) for collecting cables 70. Collection may include releasing fixture 50 from mechanical arm 16 and/or opening clamps 54 to remove cables 70. As such, the positive response can also include releasing clamps 54, whether by manually flipping tabs 56 upward (e.g., away from pad 46) or through automation, thereby allowing removal of polished cables 70 and, optionally, insertion of a next batch of cables for polishing.
On the other hand, upon a negative response, mechanical arm 16 can return fixture 50 to its polishing position at polishing station 300 for additional polishing. Thus, the negative response can also instruct polishing platform 12 to speed up, thereby saving processing time.
The skilled artisan will appreciate that the steps of polishing, washing, and inspection may be performed as a single cycle, as a series of cycles, or the steps be reordered over multiple cycles as desired. For instance, the method may perform two or more polishing and washing steps prior to the inspection step. In some instances, polishing with different polishing films 80, such as progressing from 3 μm to 9 μm diamond films, may be performed prior to inspection.
After removal, cables 70 are packaged using approaches known in the art for use in a variety of industries such as telecommunications, medical diagnostics, medical therapeutics (e.g. surgery and dentistry), automotive, lighting, mechanical inspection and analytical instrumentation, military and aerospace industries.
The foregoing disclosure of exemplary embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many variations and modifications of the embodiments described herein will be apparent to one of ordinary skill in the art in light of the above disclosure. As example, the methods may also include a pretreatment step, where the cables 70 are pretreated with a solution prior to polishing. In some embodiments, the pretreatment occurs by dipping the cables 70 in the ultrasonic bath.
Further, in describing representative embodiments, the specification may have presented the method and/or process as a particular sequence of steps. However, to the extent that the method or process does not rely on the particular order of steps set forth herein, the method or process should not be limited to the particular sequence of steps described. As one of ordinary skill in the art would appreciate, other sequences of steps may be possible. Therefore, the particular order of the steps set forth in the specification should not be construed as limitations on the claims.
While the invention is susceptible to various modifications, and alternative forms, specific examples thereof have been shown in the drawings and are herein described in detail. It should be understood, however, that the invention is not to be limited to the particular forms or methods disclosed, but to the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the scope of the appended claims.

Claims

1. A method of polishing optical cables, the method comprising the steps of:

a) providing a polishing assembly loaded with a polishing film, the polishing assembly comprising a platform to which the polishing film is loaded, the platform configured to rotate according to a dual orbital motion and coupled to a force gauge that measures downward force applied against the platform, a mounting fixture configured to mount a plurality of optical cables, the mounting fixture attached to a movable arm that moves the mounting fixture towards and away from the platform;

b) mounting a plurality of optical cables to the mounting fixture;

c) pressing the optical cables against the rotating polishing film while simultaneously monitoring the downward force applied against the platform; and

d) adjusting the downward force to remain within a prescribed tolerance.

2. The method of claim 1, wherein the fixture comprises a plurality of clamps that clamp the plurality of optical cables in place, wherein the plurality of clamps each comprise a moveable tab that locks closed using magnetic force.

3. (canceled)

4. The method of claim 1, wherein the fixture and the platform are adjustably aligned parallel to one another, preferably by way of adjustment dials that adjust the fixture and platform, the adjustment dials optionally being 4-way adjustment dials.

5. The method of claim 1, wherein rotation of the polishing film increases gradually.

6. The method of claim 1, wherein no one cable repeats its same position on the polishing film during polishing.

7. The method of claim 1, wherein the arm presses the cables against the rotating polishing film gradually to polish the cables at a lower pressure followed by polishing the cables at a higher pressure.

8. The method of claim 7, wherein the higher pressure is about 0.5-1 lb. of pressure per cable.

9. The method of claim 1, wherein the force gauge is in physical-force communication with the platform, thereby measuring pressure directly applied to the platform.

10. The method of claim 1, wherein the downward force is adjusted by a feedback mechanism that functionally couples the force gauge to the arm.

11. The method of claim 1, further comprising washing the polished optical cables in an ultrasonic bath, the bath optionally comprising deionized water and/or isopropyl alcohol.

12. The method of claim 1, further comprising optically inspecting a polished surface of the cables, and optionally repeating steps (c) and (d) until the polished surface meets a final acceptable standard, optionally using a series of different polishing films.

13. The method of claim 12, wherein the optical inspection includes inspection by camera that the camera relays inspection footage to a computer, optionally loaded with software that compares the polish to an intermediate or final standard.

14-15. (canceled)

16. A polishing assembly comprising:

a) a platform configured to receive a polishing film and configured to rotate according to a dual orbital motion;

b) a force gauge functionally coupled to the platform and configured to measure downward force applied against the platform;

c) a mounting fixture configured to mount a plurality of optical cables; and

d) a movable arm configured to move the mounting fixture downwards to press mounted cables against the polishing film, upwards to pull the mounted cables away from the polishing film, and to rotate circularly along a continuous circular path.

17. The assembly of claim 16, wherein the fixture comprises a plurality of clamps that clamp the plurality of optical cables in place, wherein the plurality of clamps each comprise a moveable tab that locks closed using magnetic force.

18. (canceled)

19. The assembly of claim 16, wherein the fixture and the platform are adjustably aligned parallel to one another, preferably by way of adjustment dials that adjust the fixture and platform, the adjustment dials optionally being 4-way adjustment dials.

20. The assembly of claim 17, wherein the force gauge is in physical-force communication with the platform, thereby measuring pressure directly applied to the platform.

21. The assembly of claim 20, wherein the force gauge communicates with the arm or with a computer that communicates with the arm.

22. The assembly of claim 16, further comprising an ultrasonic bath, the bath optionally comprising deionized water and/or isopropyl alcohol.

23. The assembly of claim 16, further comprising an optical inspection station comprising a camera that relays inspection footage to a computer, optionally loaded with software that compares the polish to an intermediate or final standard.

24-26. (canceled)

27. A mounting fixture configured to mount a plurality of optical cables, the fixture comprising a planar surface comprising a plurality of apertures for receiving a plurality of optical cables; a plurality of arms that rock open and closed to release and lock the cables in place; a plurality of magnets that magnetically lock the arms closed; and a means for coupling the mounting fixture to a polishing assembly.