CN111183107B - Apparatus and method for reducing whip damage to a wound optical fiber - Google Patents

Abstract

An apparatus (10) for reducing fiber whip damage to an optical fiber (42) wound on a fiber winding spool (40) is provided. The apparatus (10) includes a fiber inlet feed mechanism (50) operatively connected to the fiber-winding spool (40) to feed the optical fiber (42) onto the fiber-winding spool (40). The apparatus (10) further includes an anti-whip shield (22) disposed substantially about the filament winding spool (40). The anti-whip shield (22) includes a first surface (26) in an inlet slot (24) aligned with and facing the filament winding spool (40), the inlet slot (24) being laterally offset from a second surface (28). The first surface (26) transitions to the second surface (28) such that the release end of the optical fiber is first directed away from the fiber-winding spool (40) into the entry slot (24) and transitions to the second surface (28).

Description

Apparatus and method for reducing whip damage to a wound optical fiber

This application claims the benefit of priority from dutch patent application No. 2019818 filed on 27/10/2017, which is filed on 29/9/2017 in accordance with 35u.s.c. § 119 claiming the benefit of priority from U.S. provisional application serial No. 62/565,688, filed on 29/9/2017, the contents of which are herein incorporated by reference in their entirety.

Technical Field

The present invention relates generally to fiber entry whip reduction apparatus and methods for preventing damage to a fiber (e.g., an optical fiber) wound onto a rotating spool caused by a whip action of a loose end of the fiber acting on the fiber already wound onto the spool.

Background

In the optical fiber manufacturing industry, long lengths of fiber are wound at high speeds on machine rotating take-up reels for transportation and handling. As the fiber is wound on the spool, the fiber is laid down on the spool in a continuous layer. In the optical fiber industry, fiber entanglement typically occurs at the draw tower where the fiber is initially drawn, as well as at the off-line screening station where the fiber is tested for strength. At each of these locations, the fibers may be wound at high speeds, e.g., in excess of 20 meters/second or more, and maintained under relatively high tension. The apparatus for winding the fibers may comprise a feeding assembly comprising several pulleys for guiding the fibers. These pulleys facilitate proper tension on the fiber as it is wound onto the spool, while the supply equipment facilitates uniform winding of the fiber onto the spool.

During winding, the fibers are prone to break due to the force applied by the winding mechanism. When fiber breakage occurs during winding, the loose end of the fiber tends to whip at a substantially high speed due to the rapid rate of rotation of the take-up spool. Uncontrolled loosening of the ends of the fibers can affect fibers that have been wound onto the spool and cause significant damage to many layers of fibers. The break event may be unpredictable and after such a break, it is necessary to stop the rotation of the spool immediately to prevent whip damage to the fiber. However, since the breakage is unpredictable and the reel cannot be stopped instantaneously, there is an unavoidable period during which the reel will continue to rotate and the fibre end will be pulled towards the reel, beyond which the fibre end can whip the fibre already wound onto the reel relatively less controllably, thereby causing damage to the fibre.

To prevent fiber whip damage to fibers that have been wound onto a spool, techniques have been developed to attempt to prevent the loose end of the fiber from striking the fiber that has been wound onto the spool. In most cases, manufacturers use protective devices or hoods for safety reasons. Despite the presence of the guard, the loose end of the optical fiber is susceptible to damage caused by contact with the guard, gaps near the guard, and contact with the wound fiber. In addition, the tails of the fibers can break into debris, which can cause greater damage to the fibers. Accordingly, it is desirable to provide enhanced apparatus and methods for reducing fiber whip damage to an optical fiber wound on a fiber-wound spool.

Disclosure of Invention

According to one embodiment, the present disclosure is directed to novel apparatus and methods for reducing or preventing fiber entry whip in an optical fiber wound on a spool by overcoming one or more of the above-mentioned deficiencies associated with fiber spooling. As used herein, "optical fiber" includes glass optical fiber and plastic optical fiber.

A primary advantage of the present disclosure is to provide an arrangement that substantially obviates one or more of the limitations and disadvantages associated with arrangements known in the art. By maintaining the free ends of the fibers against the entry slots in the whip shield, the fibers are directed away from the wound fibers and can enter the smooth continuous inner surface of the shield in a manner that minimizes damage to the fibers.

According to one embodiment, an apparatus for reducing fiber whip damage to an optical fiber wound on a fiber-winding spool is provided. The apparatus includes an anti-whip shield disposed substantially about the filament-winding spool, the anti-whip shield including a first surface in an inlet slot aligned with and facing the filament-winding spool, the inlet slot aligned with the fiber being fed by the moving fiber source such that during a fiber break event, a loose end of the optical fiber is directed away from the filament-winding spool into the inlet slot and against the first surface. The whip shield includes a second surface facing the spool, wherein the first surface of the entry slot transitions to the second surface to transition the loose end of the optical fiber from the first surface to the second surface.

According to another embodiment, a method for reducing fiber whip damage to fiber wound on a fiber winding spool. The method comprises the following steps: the method includes feeding an optical fiber from a fiber source onto a fiber-winding spool, guiding a loose end of the optical fiber into an entry slot in an anti-whip shield, the entry slot being formed to have a first inner surface, and redirecting the loose end of the optical fiber from the entry slot to a smooth, continuous second surface on the inner surface of the anti-whip shield.

Drawings

FIG. 1 is a side view of a fiber entry whip reduction apparatus according to one embodiment;

FIG. 2 is a perspective view of a filament winding device of the fiber entry whip reducing apparatus shown in FIG. 1;

FIG. 3 is a perspective front view of an anti-whip shield for the fiber entry whip reducing apparatus;

FIG. 4 is a front view of the anti-whiplash shield shown in FIG. 3;

FIG. 5 is a perspective cross-sectional view taken through line V-V of FIG. 3 and further illustrating the anti-whiplash shield;

FIG. 6 is a cross-sectional view of the anti-whiplash shield taken through line V-V of FIG. 3;

FIG. 7 is a rear perspective view of the anti-whiplash shield shown in FIG. 3;

FIG. 8 is a perspective cross-sectional view of the anti-whiplash shield taken through line VIII-VIII of FIG. 7;

FIG. 9 is a cross-sectional view of the anti-whiplash shield taken through line VIII-VIII of FIG. 7; and

fig. 10 is a cross-sectional view taken through line X-X of fig. 4 and further illustrating the fiber entry whip reducing apparatus.

Detailed Description

Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. A preferred embodiment of a fiber entry whip reducing apparatus is shown in fig. 1-10 and is generally referred to by the reference numeral 10 throughout the drawings.

Fig. 1 and 2 illustrate a fiber entry whip reducing apparatus 10, according to one embodiment, for reducing fiber entry whip caused by loose tails of fibers, such as optical fibers used in telecommunications applications, during, for example, manufacturing and winding storage of the fibers. The fiber inlet whip reduction apparatus 10 includes a fiber winding device 20 having an anti-whip shield 22 substantially surrounding a fiber winding spool 40 on which a fiber 42 is wound during the winding process. The filament winding spool 40 is rotated by a motor (not shown) that applies tension to the fibers 42 and winds the fibers 42 onto the spool in a plurality of overlapping fiber layers.

The fibers 42 may enter the filament winding device 20 through a fiber inlet feed mechanism 50, which in one embodiment, the fiber inlet feed mechanism 50 is shown as a pulley arrangement. In the illustrated embodiment, the pulley arrangement includes a feed pulley 14 that directs the fibers 42 into the fiber inlet whip reducer 18. The pulley arrangement may optionally include, but is not limited to, an inlet pulley 12 that receives fibers from the fiber source and helps guide the fibers 42 and maintain tension on the fibers 42. The exit pulley 16 redirects the fiber 42 from the supply pulley 42 to the spool 40.

The fibers 42 may be wound onto the fiber winding spool 40 at a relatively high speed, for example, about 30m/s, 40m/s, 50m/s, 60m/s, 70m/s, or possibly even higher draw speeds. The fiber 42 is also maintained under sufficiently high tension to ensure proper winding onto the fiber-winding spool 40. If the fiber 42 is an optical fiber, it may be supplied directly from any known type of drawing equipment (not shown) or known type of optical fiber drawing or other screening device (not shown) or other fiber source.

Ideally, if the filament-winding spool 40 is suspended in free space, no protective shield or guard is required around the spool 40. However, as shown in fig. 1 and 2, to contain the fiber 42, to prevent damage to the fiber that has been wound on the spool 40, and to prevent injury to an operator standing near the spool 40 if the fiber 42 breaks, a whip shield 22 is installed around the fiber-wound spool 40. In practice, if the fiber 42 breaks, the loose end of the fiber wound onto the spool 40 at high speed will remain against the inner surface of the whip shield 22 due to centrifugal force and upward movement of the fiber. However, in conventional arrangements, there is a barrier to access to the filament winding device 20 because the whip shield 22 creates several edges against which the fibers can catch. If not addressed, any edge of the whip shield 22 may cause the fiber end or tail to wrap itself around the edge and whip back on the wound fiber 42 on the spool 40 as the loose end of the fiber enters the spool area.

The illustrated version of the fiber inlet whip reducing apparatus 10 includes a fiber inlet feed mechanism 50, shown as having an outlet pulley 16, the outlet pulley 16 for receiving the fiber 42 wound around the inlet pulley 12 and the feed pulley 14. Thus, during the filament winding operation, exit pulley 16 redirects the fiber 42 onto the filament winding spool 40. A fiber inlet feed mechanism 50 feeds fibers 42 from a fiber source onto the fiber winding spool 40. The inlet whip reducer 18 is an optional device that may be used and is located above the outlet pulley 16 to guide the fiber tail (during a fiber break event) onto the inner surface of the whip shield 22 and reduce the whip action of the fibers 42 during the break as the fiber tail passes from the supply pulley 14 and over the outlet pulley 16. The inlet whip reducer 18 may or may not be included. In one embodiment, the entry whip reducer 18 may include one or more guide channels for guiding the fibers 42 to the inner surface of the anti-fiber whip device and for reducing or controlling the whip action of the fibers 42 when the fibers 42 are broken or cut during fiber wrapping.

In the illustrated embodiment, a fiber inlet feed mechanism 50 may be operatively connected to the filament winding spool 40 to feed the optical fiber 42 onto the filament winding spool 40. According to one embodiment, the fiber inlet feed mechanism 50 may include the outlet pulley 16 as well as the inlet pulley 12 and the feed pulley 14. It should be understood that other feeding mechanisms may be used to feed the optical fiber 42 onto the fiber-winding spool 40 according to other embodiments.

The fiber entry whip reducing apparatus 10 also includes an anti-whip shield 22 disposed substantially about the fiber winding spool 40. Thus, the whip shield 22 receives the end of the fiber 42 in the whip shield 22 when the fiber 42 is cut or broken, and prevents damage caused by the end of the fiber 42, as well as damage caused by the whip action of the fiber end on the wound fiber on the fiber winding spool 40, when the end of the fiber 42 winds around the fiber winding spool 40 due to centrifugal force and forward movement and contacts the whip shield 22. The anti-whiplash shield 22 is illustrated in fig. 3-9 as a generally annular shield having an inner side and an outer side. The whip shield 22 includes a first surface 26 formed on the inside of the inlet slot 24 that faces the filament winding spool 40. The first surface 26 is received in a first elongated inlet slot 24 provided in the inner side of the anti-whip shield 22. The inlet slot 24 encompasses the first surface 26 which is aligned with the fiber 42 being fed from the fiber inlet feed mechanism 50 such that the loose end of the moving optical fiber 42 (e.g., as may occur during a fiber break event) is directed away from the fiber winding spool 40 into the inlet slot 24 due to centrifugal force and forward motion. The anti-whip shield has a second surface 28 facing the spool 40. In the inner surface of the anti-whip shield 22, a second surface 28 is formed laterally offset from the first surface 26. At the inlet slot, the second surface 28 has a slot depth that is less than the depth of the first surface 26. The first surface 26 extends around the inner surface of the whip shield 22 and transitions to the second surface 28 in a spiral shape. The transition from the first surface 26 to the second surface 28 preferably occurs within one revolution of the fiber winding spool or 360 degrees of the whip shield 22. The depth of the first surface 26 and the second surface 28 is the same at the location where the first surface 26 transitions to the second surface 28. Thus, on the second surface 28, the anti-whip shield 22 is substantially circular or annular, and the inlet groove 24 forming the first surface 26 and opening of the first surface 26 to the second surface 28 is substantially helical in the axial direction. Thus, when the fiber 22 is cut or broken, the loose end of the fiber 42 enters the inlet slot 24 and is contained within the first surface 26 for approximately one revolution or less of the spool 40 and surrounding anti-whip shield 22, and then transitions to the second surface 28 over a 360 degree rotation. The end of the fiber 42 then remains against the second surface 28 until the filament winding spool 40 slows and stops.

The anti-whip shield 22 is shown having an outer surface 30 extending around an outer perimeter of the anti-whip shield 22, and first and second opposing sidewalls 32, 34 defining sides of the anti-whip shield 22. The outer surface 30 has a transition surface 36 that is radially directed to join the surrounding transition of the outer surface 30. The first surface 26 leads from the inlet slot 24 to the second surface 28 through the transition, the first surface 26 preferably having a smooth surface that allows the ends of the cut or broken fibers 42 to pass uninterrupted due to centrifugal force and forward movement to minimize any further whipping action or breakage of the fibers 42. Once the ends of the fibers 42 pass from the first surface 26 to the second surface 28 through the inlet slot 24, the ends of the fibers 42 remain positioned within the second surface 28. The second surface 28 preferably has a smooth profile that also does not cause any further breakage of the fibers 42 when the ends of the fibers 42 are rotated due to centrifugal forces. In the embodiment shown, second surface 28 is a cylindrical uninterrupted channel having a circular cross-section with a fixed radius and is continuous, smooth and uninterrupted such that the end of moving fiber 42 passes smoothly along second surface 28 until filament-winding spool 40 stops rotating.

In the illustrated embodiment, the fiber inlet whip reducing apparatus 10 can optionally include a fiber inlet feed mechanism 50. The fiber inlet feed mechanism 50 may be operatively connected to the whip shield 22 such that the fiber inlet feed mechanism 50 and whip shield 22 move in unison to feed the fibers onto the fiber winding spool 40 and, when a break or cut occurs, to shield the ends of the fibers 42 in a manner that reduces or prevents damage to the fibers 42. However, having a fiber inlet feed mechanism (e.g., as illustrated) is not critical, and other methods of supplying optical fibers may be provided, as is known in the art. The fiber inlet feed mechanism 50 may be fixedly connected to the whip shield 22 such that the fiber 42 passes through the inlet slot 24 as the fiber 42 passes from the outlet pulley 16 onto the fiber-winding spool 40. According to one embodiment, the filament winding spool 40 rotates to wind the filament 42 onto the spool 40, but is laterally fixed so that it does not move laterally. The fiber inlet feed mechanism 50 moves laterally across the length of the spool 40 to uniformly direct the fibers 42 onto the fiber winding spool 40. In this embodiment, a motor or other actuator (not shown) may be used to move the fiber inlet feed mechanism 50 and the whip shield 22 back and forth laterally together. According to another embodiment, the fiber inlet feed mechanism 50 and the anti-whip shield 22 may be fixed in position, while the fiber winding spool 40 may be actuated by another motor (not shown) to move the spool laterally left and right in addition to rotating it.

The side of the whip shield 22 at the inlet slot 24 may include a fiber line cut-out 52, as seen in fig. 3, that provides a way to center the fiber 42 in the inlet slot 42 as the fiber 42 is wound onto the fiber-winding spool 42. Due to the fixed relationship and constant contact of the whip shield 22 with the inlet whip reducer 18, the whip shield 22 is maintained in the correct position to grasp the free end of the fiber 42 when the fiber 42 is broken or cut. The inlet slot 24 is thus in line with the exit path of the inlet whip reducer 18 and at the same approximate distance and height to provide a smooth transition of the ends of the fibers 42. Once the end of the fiber 42 moves inside the inlet slot 24, the rotational force of the rotating filament-winding spool 40 keeps the end of the fiber 42 pressed outward against the first surface 26 and away from the rotating filament-winding spool 40. The walls of inlet slot 24 extending across first surface 26 as shown in fig. 5 and 6 receive the ends of fibers 42 and direct fibers 42 in a desired direction. According to one embodiment, the side walls forming the inlet slot 24 may be tapered or angled. In one embodiment, the first surface 26 of the inlet slot 24 is contoured with a decreasing radius to gradually move the ends of the fibers 42 radially inward. For approximately the first half rotation (i.e., 180 °) through the first surface 26 of the inlet slot 24, the shape of the inlet slot 24 does not deviate axially, as seen in fig. 5 and 6. For approximately the second half of the revolution, the shape of the inlet slot 24 spirals axially, as shown in fig. 7-9, and has a small slope until it transitions to the second surface 28. This directs the end of the fiber 42 toward the cylindrical second surface 28 of the whip shield 22, where the end of the fiber 42 remains in the second surface 28 until the spool 40 stops rotating. The ends of the fibers 42 are retained in the cylindrical second surface 28 by the rotational forces and the channel walls that help prevent the fibers 42 from moving laterally. When a cut or break is detected, the inlet whip reducer 18 stops traveling almost immediately and the whip shield 22 is located almost directly above where the end of the fiber 42 hits the filament winding spool 40. This position means that the fiber end has only a minimal amount of lateral deflection between the fiber tip and its position on the spool 40. Low lateral deflection, stiffness of the fiber, high rotational force, cylindrical width and channel walls hold the fiber tip in the cylindrical second surface 28 until the spool stops rotating.

When rotating in a cylinder, there is no radial gap through or over which the fibers 42 need to pass. The smooth second surface 28 of the whip shield 22, the hard protective coating of the fibers 42, and the lack of any gaps create an environment that allows the fibers 42 to rotate in a cylinder while preventing any sharp reductions that could result in whip damage to the upper layers of the fiber groups and the spool 40.

When the filament winding spool 40 decelerates to a stop, the inlet whip reducer 18 may be lifted from the anti-whip shield 22 to facilitate unloading of the filament winding spool 40 and loading of a new, empty filament winding spool 40. Since the inlet whip reducer 18 is positioned adjacent to and does not form part of the cylindrical passage of the first surface 26, the whip reducer 18 can be lifted off without interfering with the end of the rotating fiber 42. However, the whip shield 22 should remain in place so as not to actuate its lateral dynamics, and may engage a brake attached to the track on which the whip shield 22 moves. The whip shield 22 may remain in this position until the filament winding spool 40 stops rotating and there is no possibility of the fiber tip touching the spool 40 or being damaged by debris generation. When the filament winding spool 40 is ready to be removed, the brake can be released and the lateral power can be activated and the whip shield 22 slid over the flange of the spool 40. Once the new reel 40 is loaded and the automatic cleaning procedure is completed with compressed air, the anti-whip shield 22 is ready to begin operation when it is desired to wind fiber onto the new fiber-winding reel 40.

Referring to fig. 10, the fiber entry whip reducing apparatus 10 is further illustrated, showing the shape of the entry slot 24 and the first surface 26 as the first surface 26 transitions to the second surface 28. The first surface 26 of the inlet slot 24 has a curved shape with a varying radius, which varies between the inlet of the inlet slot 24 and the transition to the second surface 28. The various radii of the first surface 26 are illustrated by radii R1-R5. The radius R1 is greater than each of the next sequential radius R2 and the subsequent sequential radii R3-R5, which are located along increasing angular positions of the anti-whip shield 22. Thus, as the fiber 42 travels from the inlet to the second surface 28, the first surface 26 transitions from a larger radius to a smaller radius. Further, a fixed radius R6 of the second surface 28 is shown. The second surface 28 has a uniform radius R6 to provide a continuous smooth surface. This further enhances the reduction of whipping of the fibers 42.

In operation, as the fiber 42 is wound onto the fiber winding spool 40, and as the fiber 42 is cut or broken, the end of the fiber 42 passes through the pulleys 12, 14, and 16 and the fiber inlet feed mechanism 50 provided by the inlet whip reducer 18. In the illustrated embodiment of the inlet whip reducer 18, by configuring the angle at which the inner surface of the inlet whip reducer 18 is aligned with the first surface 26 so that the end of the fiber 42 will then continue into the inlet groove 24 and move outward in the inlet groove 24, fiber whip is minimized as the end of the fiber 42 passes over the outlet pulley 16. Thus, when a fiber break occurs, due to the centrifugal force of the fiber traveling around the exit pulley 16, the fiber is first forced against the curved surface of the whip reducer 18 aligned with the first surface 26, thereby guiding the fiber through the curved surface of the whip reducer 18 to contact and push against the first surface 26 and through a complete transition of about 360 degrees along the first surface 26 where the fiber then transitions and enters the second surface 28. The second surface 28 thereby smoothly controls and isolates the ends of the fibers 42 from the remainder of the fibers 42 to prevent or minimize damage to the fibers 42 being wound on the filament winding spool 40. Once the end of the fiber 42 passes over the second surface 28 of the whip shield 22, the tip of the fiber 42 will continue to rotate smoothly in a circular path without interruption until the filament-winding spool 40 reaches a substantially complete stop.

Thus, the fiber inlet whip reducing apparatus 10 advantageously controls the whip action of the cut or broken fibers 42 to minimize damage to the fibers 42 as the fiber ends pass along the inner surface of the whip shield 22. The novel whip shield 22 thus prevents further breakage of the ends of the fibers 42 and prevents the generation of debris that may further damage the fibers 42 wound on the fiber-winding spool 40.

The embodiments described herein are preferred and/or illustrative, but not restrictive. Various modifications are within the purview and scope of the claims appended hereto.

Claims (10)

1. An apparatus for reducing fiber whip damage to an optical fiber wound on a fiber-winding spool, comprising:

an anti-whip shield disposed substantially about the fiber-winding spool, the anti-whip shield including a first surface in an inlet slot aligned with and facing the fiber-winding spool, the inlet slot aligned with the fiber being fed by the moving fiber source such that, during a fiber breakage event, a loose end of the optical fiber is directed away from the fiber-winding spool into the inlet slot and against the first surface;

the anti-whip shield including a second surface facing the spool, wherein the first surface of the entry slot transitions to the second surface to transition the loose end of the optical fiber from the first surface to the second surface,

wherein the first surface remaining in the inlet slot has a curved shape with a varying radius and the second surface has a substantially uniform radius.

2. The apparatus of claim 1, wherein the inlet slot is laterally offset from the second surface.

3. The apparatus of claim 1, wherein the inlet slot transitions from the first surface to the second surface in one revolution of the filament winding spool.

4. The apparatus of claim 1, wherein the second surface of the anti-whip shield is substantially annular, and wherein the inlet slot is substantially helical.

5. The apparatus of claim 1, further comprising a fiber inlet feeding mechanism operatively connected to the fiber-winding spool to feed the optical fiber onto the fiber-winding spool.

6. The apparatus of claim 5 wherein the fiber inlet feed mechanism comprises a fiber inlet whip reducer.

7. The apparatus of claim 5, wherein the fiber inlet feed mechanism includes at least one outlet pulley.

8. A method for reducing fiber whip damage to fiber wound on a fiber winding spool, the method comprising the steps of:

feeding an optical fiber from a fiber source onto a fiber winding spool;

directing the loose end of the fiber into an entry slot in an anti-whip shield, the entry slot formed to have a first inner surface; and

redirecting the loose end of the fiber from the inlet slot to a smooth continuous second surface on the inner surface of the anti-whip shield,

wherein the first surface of the inlet slot has a curved shape with a varying radius and the second surface has a substantially uniform radius, and

wherein the inlet slot is laterally offset from the second surface.

9. The method of claim 8, wherein the first surface of the entrance slot transitions to the second surface such that the loose end of the optical fiber is directed through the entrance slot and onto the second surface.

10. The method of claim 8, wherein the second surface of the anti-whip shield is substantially annular, and wherein the inlet slot is substantially helical.

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