RU2772442C2 - Hydrostatic bearings containing fiber support channel for supporting optical fiber during optical fiber extraction - Google Patents

Abstract

FIELD: fiber manufacturing.

SUBSTANCE: invention relates to hydrostatic bearings containing a fiber support channel for supporting optical fiber during optical fiber extraction, and a method for manufacturing optical fiber. A hydrostatic bearing is described for guiding optical fibers during the manufacturing process. The hydrostatic bearing provides a fluid flow for lifting and guiding optical fiber along a technological route. Optical fiber is in a fiber groove and is subjected to the action of lifting force from fluid flowing from the inner radial position of the fiber groove away from optical fiber to the outer radial position of the fiber groove. The lifting force of fluid acting on optical fiber is described by a convex force profile, according to which the lifting force acting on optical fiber is increased, when optical fiber is moved deeper to the groove. Different designs of hydrostatic bearings for achieving the convex force profile are described.

EFFECT: better stability of positioning optical fiber in a fiber groove is achieved, and contact of optical fiber with solid surfaces of a hydrostatic bearing is prevented.

26 cl, 32 dwg

Description

This application claims priority under 35 USC. §119, U.S. Provisional Application US 62/573343 dated October 17, 2017 which claims priority of U.S. Provisional Application US 62/559764 dated September 18, 2017, which in turn claims priority of Dutch Patent Application No. 2019489 dated 6 September 2017 and U.S. Provisional Application US 62/546163 dated August 16, 2017, the entire contents of which are incorporated herein by reference.

Technical field

The present description relates broadly to methods for drawing optical fibers using systems for the production of optical fibers containing hydrostatic bearings.

State of the art

Conventional methods and manufacturing processes for making optical fibers typically involve pulling the optical fiber down along a linear path through the manufacturing steps. However, this method creates significant obstacles to the improvement and modification of optical fiber production. For example, equipment associated with in-line production of optical fibers is usually placed in a single line from top to bottom, making it difficult to add steps or change a process without increasing the height of the entire system. In some cases, adding to a linear production system requires additional construction to increase the height of the production building (for example, when an exhaust tower is located on or near the ceiling of an existing building). Such obstacles lead to significant costs in order to provide modification or upgrade of systems and equipment for the production of optical fiber.

Creating systems and methods that would allow a manufacturer to eliminate the need to use only linear systems would greatly reduce the cost of implementing modifications or upgrades. For example, in a system that allows horizontal pull (as opposed to or in addition to vertical pull), it would be much easier and cheaper to place additional components and equipment in the manufacturing system. In addition, such configurations could provide more efficient processing routes, allowing the use of cheaper polymers, higher coating rates, and improved fiber cooling technologies.

The essence of the invention

A hydrostatic bearing for guiding optical fibers during production is presented. The hydrostatic bearing provides fluid flow (hereinafter hydrodynamic flow) to lift and guide the optical fiber along the process path. The optical fiber is in the fiber slot and is subjected to lift from the flow flowing from the inner radial position in the fiber slot past the optical fiber to the outer radial position of the fiber slot. Since optical fiber is flexible, and given that it is in the presence of high-speed hydrodynamic flows, vibrations can be excited in the fiber. Since the fiber is subjected to strong centering forces in the slot, vibrations will occur in the radial direction of the slot. Since the fiber has inertia, these vibrations will cause momentary downward radial forces on the fiber which, if strong enough, can cause the fiber to come into contact with the bottom of the slot or the bottom of the fluid passage. This contact will cause damage to the fiber surface resulting in a significant reduction in strength. The present application discusses fiber slot designs that require more energy for the fiber to enter the bottom of the slot and thereby divert the kinetic energy of the oscillating fiber causing it to move downward before it contacts the bottom of the slot or fluid channel. For some of the considered slot designs, the uplifting force of the flow acting on the optical fiber across the radial opening of the slot is described by a convex force curve (force profile), according to which the uplifting uplifting force acting on the optical fiber increases as the optical fiber is moved deeper into the slot. For other considered slot designs, the lifting force on the fiber increases sharply in the area directly above the bottom of the slot. In either design, the optical fiber is prevented from contacting the hard surfaces of the hydrostatic bearing as the fiber oscillates. Various designs of hydrostatic bearings have been described to achieve a convex force profile through a radial slot opening or to increase the force directly over the bottom of the slot.

A hydrostatic bearing for guiding optical fibers during manufacturing is presented. The hydrostatic bearing provides hydrodynamic flow to lift and guide the optical fiber along the process path. The hydrostatic bearing includes a fiber slot and a fluid slot. The optical fiber is in the fiber slot and is subjected to lift from fluid flowing out of the fluid slot. The fluid slot is at the inner radial position of the hydrostatic bearing and the fiber slot is at the outer radial position of the hydrostatic bearing. The fluid slot is in fluid communication with the fiber slot. The flow flows through the fluid slot to the fiber slot and out of the fiber slot opening. The optical fiber enters the fiber slot through the hole and is subjected to the lifting force exerted by the flow. The uplifting force of the flow acting on the optical fiber is described by a convex force profile, whereby the upward (uplifting) force on the optical fiber increases as the optical fiber moves deeper into the slot. A better positioning stability of the optical fiber in the fiber slot is achieved and the contact of the optical fiber with the hard surfaces of the hydrostatic bearing is prevented. This document describes various designs of hydrostatic bearings to achieve a convex force profile.

The present invention relates to a method for producing an optical fiber, including:

guiding the bare optical fiber along the first path to the hydrostatic bearing, the hydrostatic bearing comprising a fiber support channel having an opening, and the fiber support channel extending from the hole in the depth direction, the bare optical fiber entering the fiber support channel through the hole; and

- flow of fluid through the fiber support channel to the opening of the fiber support channel, whereby the fluid contacts the bare optical fiber and provides a lifting force to the bare optical fiber, and the lifting force is determined by a force profile describing the dependence of the lifting force on the depth of the bare optical fiber fibers in the channel to support the fiber, and the force profile is convex.

Additional features and advantages of the methods and systems described herein will be set forth in the following detailed description, and in part will become apparent to those skilled in the art from this description, or will be apparent from practice of the embodiments described herein, including the detailed description below, the claims, as well as the attached drawings.

It should be understood that both the foregoing general description and the following detailed description disclose various embodiments and are intended to provide an overview or basis for understanding the nature and nature of the claimed subject matter. The accompanying drawings are used to facilitate understanding of the various embodiments and are incorporated herein as part of this specification. The drawings illustrate various embodiments described herein and, together with the description, serve to explain the principles and operations of the claimed subject matter.

Brief description of the drawings

The embodiments shown in the drawings are illustrative and by way of example, they are not intended to limit the subject matter of the invention as defined by the claims. The following detailed description of illustrative embodiments will become apparent when read in conjunction with the following drawings, in which like structures are identified by like reference numerals and in which:

fig. 1 is a schematic illustration of a system for producing optical fiber in accordance with one or more of the embodiments shown and described herein;

fig. 2 shows an exploded view of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 3A shows a partial side view of the hydrostatic bearing of FIG. 2 in accordance with one or more of the embodiments shown and described herein;

fig. 3B shows a partial front view of the hydrostatic bearing of FIG. 2 in accordance with one or more of the embodiments shown and described herein;

fig. 4A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 4B shows a partial front view of the hydrostatic bearing of FIG. 4A in accordance with one or more of the embodiments shown and described herein;

fig. 5A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 5B shows a partial front view of the hydrostatic bearing of FIG. 5A in accordance with one or more of the embodiments shown and described herein;

fig. 5C shows a partial plan view of the hydrostatic bearing of FIG. 5A in accordance with one or more of the embodiments shown and described herein;

fig. 6A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 6B shows a partial front view of the hydrostatic bearing of FIG. 6A, in accordance with one or more of the embodiments shown and described herein;

fig. 7A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 7B shows a partial front view of the hydrostatic bearing of FIG. 7A, in accordance with one or more of the embodiments shown and described herein;

fig. 8A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 8B shows a partial front view of the hydrostatic bearing of FIG. 8A, in accordance with one or more of the embodiments shown and described herein;

fig. 9A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 9B shows a partial front view of the hydrostatic bearing of FIG. 9A, in accordance with one or more of the embodiments shown and described herein;

fig. 9C shows a partial plan view of the hydrostatic bearing of FIG. 9A, in accordance with one or more of the embodiments shown and described herein;

fig. 10A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system, in accordance with one or more of the embodiments shown and described herein;

fig. 10B shows a partial front view of the hydrostatic bearing of FIG. 10A, in accordance with one or more of the embodiments shown and described herein;

fig. 11A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 11B shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 12A show the force profile for two fiber slot designs;

fig. 12B shows two fiber slot designs;

fig. 12C shows a convex force profile having line segments;

fig. 12D shows a convex force profile having curved segments;

fig. 12E shows a non-convex force profile having line segments;

fig. 12F shows a non-convex force profile having curved segments;

fig. 13A shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein;

fig. 13B shows a partial front view of the hydrostatic bearing of FIG. 13A, in accordance with one or more of the embodiments shown and described herein; and

fig. 14 shows a partial side view of another embodiment of a hydrostatic bearing for use in an optical fiber production system in accordance with one or more of the embodiments shown and described herein.

fig. 15 shows a hydrostatic bearing having a fiber slot in combination with inclined and vertical inner walls.

Detailed description

Embodiments of methods and systems for producing optical fiber will now be discussed in detail, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numbers will be used throughout the drawings to refer to the same or similar parts. More specifically, the methods and systems described herein relate to obtaining optical fibers along a draw path that includes one or more non-vertical path sections supported by one or more hydrostatic bearings. Further, each of said one or more hydrostatic bearings includes a fiber support channel to provide a liquid or air cushion to the optical fiber located in the fiber support channel. The embodiments described herein provide flexibility in optical fiber manufacturing by allowing non-vertical fiber paths to be routed through all stages of production, including prior to coating. Various embodiments of methods and systems for the production of optical fibers will be described herein with specific reference to the accompanying drawings.

Let us turn to Fig. 1, which schematically shows an optical fiber manufacturing system 100 for manufacturing optical fiber. The optical fiber production system 100 includes a drawing oven 110, a fiber cooling mechanism 112, one or more hydrostatic bearings 120, a fiber coater 114, and a fiber collector 116. As shown in FIG. 1, draw path 102 extends from draw oven 110 to fiber collector 116 and is the path along which optical fiber 10 travels during production. The draw path 102 includes one or more draw path sections, such as a first draw path section 102a, a second draw path section 102b, and a third draw path section 102c. Further, these portions of the pull path may be vertical (denoted by direction "A") or non-vertical (denoted by direction "B"). During manufacture, optical fiber 10 may be guided through one or more non-vertical draw path sections (eg, second draw path section 102b) by one or more hydrostatic bearings 120, described in more detail here.

As shown in FIG. 1, an optical fiber drawing preform 12 is placed in a drawing oven 110 and a fiber is drawn from it to form an uncoated optical fiber 14. The optical fiber drawing preform 12 can be made from any glass or material suitable for making optical fibers. Further, as used herein, "uncoated optical fiber" refers to an optical fiber directly drawn from a preform and before one or more coating layers are applied to its outer surface (for example, before the bare optical fiber is coated with one or more coating layers, such as as protective coatings based on polymers). The expression "optical fiber 10" may refer to an uncoated optical fiber 14 or a coated optical fiber 20 (ie, an optical fiber with one or more coating layers deposited on it).

During the manufacturing process, the bare optical fiber 14 is drawn from the fiber drawing preform 12, exits the drawing oven 110, travels along the first section 102a of the drawing path in direction A, then reaches the first hydrostatic bearing 120a of one or more hydrostatic bearings 120, and deviates from the first section. 102a of a pull path extending in direction A (substantially vertical) to second pull path section 102b moving in direction B. Along second pull path section 102b, bare optical fiber 14 may pass through fiber cooling mechanism 112. As shown, the second draw path section 102b is oriented orthogonally (eg, horizontally) to the first draw path section 102a, but it should be understood that the systems and methods described herein may redirect optical fiber 10 (eg, bare optical fiber 14) along any non-vertical path to ( or after) applying a coating layer 21 thereon.

Providing an optical fiber production system that includes one or more non-vertical paths, for example prior to coating bare optical fiber 14, provides many advantages. For example, in a conventional in-line fiber system, adding new or additional components prior to the fiber coater 114, such as additional coaters and additional cooling mechanisms, would require all such components to be mounted vertically, often requiring an increase in the height of the entire system. With the optical fiber fabrication system 100 described herein, the optical fiber 10 can be routed horizontally or diagonally (e.g., deviated from vertical) prior to coating layer 21, which provides more flexibility not only in equipment placement, but also in more late modifications, additions and modernization of existing production equipment without the need to increase the height of the system as a whole.

According to FIG. 1, the bare optical fiber 14 is cooled as it passes through the fiber cooling mechanism 112 and prior to processing in the fiber coater 114, where a coating layer 21 (e.g., a primary protective coating layer) is applied to the outer surface of the bare optical fiber 14, thereby forming a coated optical fiber 20. The fiber cooling mechanism 112 may be any mechanism known in the art for cooling optical fiber. For example, the fiber cooling mechanism 112 may be filled with a gas that can facilitate cooling of the bare optical fiber 14 at a rate greater or less than the rate at which the bare optical fiber 14 is cooled in air. It should be understood that the fiber cooling mechanism 112 is an optional component, and in other embodiments, the optical fiber production system 100 may not include the fiber cooling mechanism 112.

In some embodiments, as shown in FIG. 1, said one or more hydrostatic bearings 120 may include a second hydrostatic bearing 120b that may be used to transport an uncoated optical fiber 14 from a second draw path portion 102b located on a straight line connecting the first and second hydrostatic bearings 120a, 120b to a third portion 102c. a pull path that may be substantially vertical and may be parallel to the first stretch path portion 102a. As shown in FIG. 1, a third draw path portion 102c extends from the second hydrostatic bearing 120b to the fiber coater 114. After exiting the fiber coating plant 114, the coated optical fiber 20 with the coating layer 21 (i.e., no longer uncoated) may pass through a number of other processing steps (not shown) in the optical fiber production system 100 before reaching the optical fiber production plant 116. fiber collection. The fiber collection facility 116 includes one or more draw mechanisms 117 used to apply tension to the coated optical fiber 20, thereby providing the necessary tension to the optical fiber 10 as it is pulled through the entire optical fiber production system 100 shown in FIG. 1. The fiber collection facility 116 also includes a fiber storage spool 118, and the coated optical fiber 20 can be wound onto the spool 118. In addition, although FIG. 1 shows three sections of the stretch path (102a, 102b, 102c), it should be understood that it is possible to have any number of sections of the path, each of which has a vertical or non-vertical orientation.

As described in more detail herein, one or more hydrostatic bearings 120 (e.g., first and second hydrostatic bearings 120a and 120b) transport the bare optical fiber 14 through the optical fiber fabrication system 100 such that the bare optical fiber 14 does not enter the mechanical contact with any surface until a coating layer 21 is applied to the uncoated optical fiber 14 (thereby forming the coated optical fiber 20). During manufacture, said one or more hydrostatic bearings 120 may provide a flow region over which the bare optical fiber 14 can move without mechanical contact with the hydrostatic bearings 120, such as a fluid flow that is chemically inert to the bare optical fiber 14 (for example, , air, helium). The term "mechanical contact" as used herein refers to contact with a solid component during the drawing process. This lack of mechanical contact can be important to maintain the quality and integrity of a fragile, uncoated optical fiber, especially a fiber that travels in a non-vertical path prior to being coated in the fiber coating facility 114. The mechanical contact provided by the fiber collector 116 is acceptable because when the optical fiber 10 reaches the fiber collector 116 it is already coated with a coating layer 21 that protects the fiber, so mechanical contact with a solid surface does not significantly affect quality or integrity. fibers to the same extent as if the fiber had not been coated. However, it should be understood that although hydrostatic bearings 120 are described here primarily as facilitating movement of uncoated optical fiber 14 along draw path 102, hydrostatic bearings 120 can be used with any optical fiber 10, such as coated optical fiber 20.

In some embodiments, said one or more hydrostatic bearings 120, while providing a cushion of liquid or air cushion over which the bare optical fiber 14 can move, can also simultaneously cool the bare optical fiber 14. For example, in embodiments without fiber cooling mechanism 112, said one or more hydrostatic bearings 120 can perform the cooling function of the fiber cooling mechanism 112 . In particular, since one or more of the hydrostatic bearings 120 uses a liquid or gas flow that supports the uncoated optical fiber 14, the uncoated optical fiber 14 cools at a rate that is higher than the rate at which the uncoated optical fiber 14 would cool in still ambient air. , which may be present directly outside the drawing oven 110. In addition, the greater the temperature difference between the uncoated optical fiber 14 and the medium in the hydrostatic bearing 120 (which is preferably air at ambient or room temperature), the greater the ability of the hydrostatic bearing 120 to cool uncoated optical fiber 14.

Let us now turn to FIG. 2, which shows the hydrostatic bearing 120 in more detail. The hydrostatic bearing 120 includes a first disc 130, a second disc 132, an inner component 136, and at least one opening 134 in at least one of the first and second discs 130, 132. The first disc 130 and the second disc 132 have an arcuate outer surface 138, 139 and are on opposite sides of each other. The arcuate outer surfaces 138, 139 are located around the perimeter of each respective disc 130, 132 and are substantially aligned with each other. Further, the first disk 130 and the second disk 132 are connected by fasteners (eg, bolts 140) to connect the first and second disks 130, 132 to each other so that fluid can pass through the hydrostatic bearing 120.

The first disk 130 and the second disk 132 each have respective inner sides 142, 144 and outer sides 143, 145. The inner side 142 of the first disk 130 faces the inner side 144 of the second disk 132, forming a fiber support channel 150 (one embodiment of which shown in Figures 3A and 3B) between the inner sides 142, 144 and extending radially inward from the arcuate outer surfaces 138, 139 of each disc 130, 132. The fiber support conduit 150 provides space for hydrodynamic flow and is configured to receive uncoated optical fiber 14 (or any other optical fiber 10) so that the bare optical fiber 14 can move along the channel 150 to support the fiber without rotation of the hydrostatic bearing 120 and without mechanical contact between the bare optical fiber 14 and the hydrostatic bearing 120. Various channel configurations are described in detail in this document. 150 for support fibers. Further, said at least one opening 134 extends through at least one of the first disc 130 and the second disc 132 and allows a fluid (e.g., air, helium, or other desired gas or liquid) to be supplied to the hydrostatic bearing 120 so that this medium could exit the hydrostatic bearing 120 through the fiber support channel 150, thereby providing a fluid or air cushion for the bare optical fiber 14 located in the fiber support channel 150 (FIG. 3A).

Referring again to FIG. 2, the hydrostatic bearing 120 may include an internal component 136 located between the first disk 130 and the second disk 132. The internal component 136 (eg, washer 137) is designed to assist in directing flow from at least one opening 134 into the channel 150 to support the fiber, so that the flow exits the channel 150 to support the fiber in the desired direction of flow. The inner component 136 is located between the first disk 130 and the second disk 132, providing a gap between them. In some embodiments, inner component 136 may include a number of pins (not shown) to further control hydrodynamic flow by suppressing non-radial flow. In addition, the inner component 136 serves as a sealing piece, ensuring that the first disc 130 and the second disc 132 are in close contact.

Let us now turn to FIG. 3A, which shows a fiber support channel 150 in more detail. As shown in Figures 3A and 3B, the fiber support channel 150 has a fiber slot 152 and a fluid slot 154. The fiber slot 152 extends radially inward from the arcuate outer surfaces 138, 139 of the discs 130, 132 (e.g., from the opening 160 between the arcuate outer surfaces 138, 139 of the first disc 130 and the second disc 132) and terminates at the fiber support channel boundary 155. The radially inward direction is also referred to herein as the depth direction, where depth refers to the position of the uncoated optical fiber in the fiber support channel. The depth in the fiber support channel is measured relative to the hole in the fiber support channel, and the direction of the depth is the direction from the hole through the fiber slot to the fluid slot. The axis corresponding to the depth direction is the central axis of the fiber support channel or an axis parallel to the central axis of the fiber support channel. In a preferred embodiment, the fiber support channel is symmetrical about a central axis in the fiber support channel. Fluid slot 154 extends radially inward from fiber support channel boundary 155 and terminates at inner component 136. During manufacture, flow may flow radially outward from inner component 136 through fluid slot 154 and fiber slot 152, providing fluid or air pad for the bare optical fiber 14 within the fiber slot 152 so that the bare optical fiber 14 can be guided along the draw path 102 (FIG. 1) without coming into mechanical contact with the hydrostatic bearing 120.

The fiber support channel 150 extends between the inner side 142 of the first disk 130 and the inner side 144 of the second disk 132, which are separated from each other by the bandwidth W _C . In the embodiment depicted in FIG. 3A, the fiber support channel 150 is tapered such that the width W _C at the opening 160 is larger than the bandwidth W _C at the fiber support channel boundary 155, and the fiber support channel 150 width W _C varies radially (e.g., varies depending on where the optical fiber 10 is located vertically within the fiber support channel 150).

Next, in FIG. 3A shows an uncoated optical fiber 14 residing in a fiber slot 152 of a fiber support channel 150 and shows fluid 151 (e.g., air) that flows from the fluid slot 154 (e.g., hydrodynamic flow from at least one orifice 134 in the first and/or second discs 130, 132) through the fiber slot 152 and which contacts the bare optical fiber 14 as it passes through the hydrostatic bearing 120. This hydrodynamic flow results in a positive pressure below the bare optical fiber 14 which acts on and supports the bottom of the bare optical fiber 14 by providing a lifting (radially outward) force, thereby lifting the bare optical fiber 14 to prevent tight mechanical contact between the bare optical fiber 14 and the hydrostatic bearing 120. Without wishing to be bound by theory, it is assumed that the pressure can be optimized so that the uncovered the optical fiber 14 was positioned and held vertically in the fiber slot 152 of the fiber support channel 150 such that the uncoated optical fiber 14 was held between the fiber support channel boundary 155 and the opening 160 of the fiber support channel 150. For example, flow 151 passing through fiber support channel 150 may have a constant flow rate that can support or support optical fiber 10 in fiber slot 152 as uncoated optical fiber 14 passes through hydrostatic bearing 120, and slot 152 is configured to fibers and/or the addition of one or more depressurization zones described below (eg, depressurization zones 270 in FIG. 4B) can facilitate self-localization of bare optical fiber 14 in fiber slot 152.

Referring again to FIG. 3A, in some embodiments, portions of the inner sides 142, 144 within the fiber slot 152 of the fiber support channel 150 may be tapered or angled such that the fiber slot 152 has a narrower bandwidth W _C at the fiber support channel boundary 155 (i.e. i.e., within the arcuate path formed by the uncoated optical fiber 14 as it passes through the hydrostatic bearing 120) than the opening 160 of the fiber support channel 150. In some embodiments, both inner sides 142 and 144 may be inclined, for example, at an angle of more than 0° to less than 10°, for example, from about 0.3° to about 7°, from about 0.4° to about 3° etc. Further, fiber support channel 150 and fiber slot 152 may be any depth and any width W _C . In various embodiments, the depth of the fiber slot 152 is greater than 0.25 inches, or greater than 0.40 inches, or greater than 0.55 inches, or greater than 0.70 inches, or greater than 0.85 inches, or lies between 0, 25 inches to 1.25 inches, or in the range of 0.35 inches to 1.05 inches, or in the range of 0.45 inches to 0.90 inches, or in the range of 0.55 inches to 0.85 inches, or in the range of 0.60 inch to 0.80 inch, or about 0.65 inch, or about 0.75 inch. Using a tapered fiber support channel 150 (as shown, for example, in FIG. 3A) and introducing fluid 151 into the fiber support channel 150 such that the fluid enters the narrower interior of the fiber support channel 150 and exits through the wider outer part of the fiber support channel 150, the liquid or air cushion formed by the stream 151 discharged through the fiber support channel 150 will cause the uncoated optical fiber 14 to self-localize in the depth of the channel 150.

Without wishing to be bound by any theory, at a given flow rate 151, the tension in the fiber creates a downward (radially inward) force that opposes the upward (radially outward) force exerted by the hydrodynamic flow 151. The position of the uncoated optical fiber 14 in the fiber support channel 150 stabilizes at the point where the downward force generated by the tension of the fiber is balanced by the lift force generated by the hydrodynamic flow 151. Tension fluctuations that can occur when the fiber is pulled change the balance of forces acting on the bare optical fiber 14, and lead to a displacement of the uncoated optical fiber 14 from its stable equilibrium position. If the tension increases, the downward force on the bare optical fiber 14 increases and the bare optical fiber 14 moves downward from its stable equilibrium position to a deeper position in the fiber support channel 150 (i.e., to a position within the fiber support channel 150). , more distant from the hole 160). If the tension is reduced, the downward force on the bare optical fiber 14 is reduced and the bare optical fiber 14 moves upward from its stable equilibrium position to a shallower position in the fiber support channel 150 (i.e., to a position inside the fiber support channel, located closer to the hole 160). Shifting the uncoated optical fiber 14 down from its stable equilibrium position may cause the uncoated optical fiber 14 to mechanically contact the fiber support channel 150 and/or may cause the uncoated optical fiber 14 to enter the fluid slot 154. Shifting the position of the bare optical fiber 14 upward from its stable equilibrium position may cause the bare optical fiber 14 to mechanically contact the fiber support channel 150 and/or may cause the bare optical fiber 14 to exit the fiber support channel 150 and exit the hydrostatic bearing 120.

In embodiments of the present invention, fiber slot 152 and/or fluid slot 154 are configured to resist up and down movement of uncoated optical fiber 14 from a stable equilibrium position caused by fluctuations or other changes in tension. For example, in FIG. 3A, the fiber slot 152 is defined by the tapered inner sides 142 and 144 of the first and second disks 130 and 132, respectively. If the fiber tension is increased, the downward force on the bare optical fiber 14 is increased and the bare optical fiber 14 will move downward (eg, radially inward) in the fiber slot 152. Tension-induced downward displacement of the bare optical fiber 14 is compensated for by the increase in lift provided by the flow 151 as the bare optical fiber 14 moves deeper (downward) within the fiber slot 152. The structure of the hydrodynamic flow 151 in the fiber slot 152 is such that part of the flow supports (lifts) the uncoated optical fiber 14, and part flows around the uncoated optical fiber 14. At a given flow rate (or pressure) of the flow 151 supplied to the fiber slot 152 from the groove 154 for fluid, the proportion of hydrodynamic flow 151 that flows around the bare optical fiber 14 depends on the spacing between the bare optical fiber 14 and the inner sides 142 and 144. Due to the taper of the inner sides 142 and 144, the gaps between the bare optical fiber 14 and the inner the sides 142 and 144 change with the position of the bare optical fiber 14 in the fiber slot 152. As the bare optical fiber 14 moves deeper in the fiber slot 152, the spaces between the bare optical fiber 14 and the inner sides 142 and 144 narrow. This leads to a decrease in the proportion of hydrodynamic flow 151 that flows around the bare optical fiber 14 and an increase in the proportion of hydrodynamic flow 151 that supports the bare optical fiber 14. As a result, when the bare optical fiber 14 moves deeper into the fiber slot 152, the lifting force ( or pressure) of the flow 151 acting on the bare optical fiber 14 increases, counteracting the downward displacement of the bare optical fiber 14 caused by the increase in tension. Similarly, if the tension is reduced, the downward tension-induced force on the bare optical fiber 14 is reduced, and the bare optical fiber 14 moves upward (radially outward in a shallower direction) in the fiber slot 152. As the bare optical fiber 14 moves upward in the fiber slot 152, the gaps between the bare optical fiber 14 and the inner sides 142 and 144 increase, and a greater proportion of the hydrodynamic flow 151 flows around the bare optical fiber 14. The lift (or pressure) of the flow 151 lifting the uncoated optical fiber 14 is correspondingly reduced to compensate for the tension-induced upward displacement of the uncoated optical fiber 14. Thus, the tension-induced displacement of the uncoated optical fiber 14 is compensated by adjusting the lift provided by the flow 151 as the position of the uncoated optical fiber 14 changes in the fiber slot 152. A new stabilized equilibrium position is reached when a balance is restored between the tension-induced downward force and the lift force generated by the flow 151. optical fiber 14 in the fiber slot 152. Tension compensation by rebalancing and rebalancing downward (radially in) and upward (radially out) forces is a feature of the hydrostatic bearing 120 embodiments described herein. Different designs of hydrostatic bearings 120 that provide tension compensation are described below.

In some embodiments, the bare optical fiber 14 may be in a vertical position within a fiber slot 152 that is about 1-2 times the diameter of the bare optical fiber 14, such as 1-1.75 times the diameter of the bare optical fiber 14, for example, about 1 to 1.5 times the diameter of the bare optical fiber 14, and the like. While not wishing to be bound by any theory, with bare optical fiber 14 in such a relatively narrow area in fiber slot 152, bare optical fiber 14 will self-center between inner sides 142 and 144 during the process due to the Bernoulli effect. For example, as uncoated optical fiber 14 approaches inner side 144 and moves away from inner side 142, flow rate 151 will increase closest to inner side 142 and decrease closest to inner side 144. In accordance with the Bernoulli effect, the increase in flow rate occurs simultaneously with decreasing pressure. As a result, the greater pressure due to the reduction in hydrodynamic flow near the inner side 144 will cause the bare optical fiber 14 to return to the center of the fiber slot 152. Thus, the bare optical fiber 14 can be centered in the fiber support channel 150 at least primarily by the Bernoulli effect due to the hydrodynamic flow flowing around the fiber and exiting the fiber support channel 150 as the fiber is drawn (i.e., when the bare optical fiber 14 passes through the channel 150 to support the fiber as it travels along the draw path 102 (FIG. 1).

Again, without wishing to be bound by theory, it is believed that such centering occurs without the need for hydrodynamic flow, which could in turn adversely affect the fiber, for example, no hydrodynamic flow jets flowing from the inner sides 142 or 144 are used. The hydrodynamic flow flowing through the fiber support channel 150 (for example, through the fiber slot 152 where the bare optical fiber 14 is located) is preferably selected to support the bare optical fiber 14 so that it is entirely within the fiber slot 152 (for example, the conical section of the channel 150 for supporting the fiber, shown in Fig. 3A). In addition, since the bare optical fiber 14 is located in the region of the fiber support channel 150 whose width is 1 to 2 diameters of the bare optical fiber 14, the bare optical fiber 14 is supported by a pressure differential present below the bare optical fiber 14 (and not by aerodynamic drag, which, however, if desired, can also be used to support the fiber). As a result of supporting or lifting bare optical fiber 14 within channel 150, much less hydrodynamic flow can be used to support the fiber by pressure drop than when using aerodynamic drag to lift the fiber.

Further, while the fiber support channel 150 includes a tapered fiber slot 152 to provide strain relief for self-localization of the uncoated optical fiber 14 within the fiber slot 152, other embodiments of the hydrostatic bearing 120 are conceivable that provide strain relief through alternative slot designs and configurations. fibers, described in more detail below. For example, some of these embodiments may include one or more pressure relief zones located in the first and/or second disks 130, 132 to provide tension compensation (e.g., pressure relief zones 270 depicted in embodiments of hydrostatic bearing 220 in FIG. 4B). However, when the hydrostatic bearing 120 includes a tapered fiber slot 152, pressure relief zones are optional and not required to provide strain relief, as shown in a partial side view of the hydrostatic bearing 120 in FIG. 3b.

Referring now to Figures 4A and 4B showing the hydrostatic bearing 220. In FIG. 4A is a partial side view of the hydrostatic bearing 220, and FIG. 4B is a partial front view of a hydrostatic bearing 220. The hydrostatic bearing 220 has a fiber support channel 250 comprising a fiber groove 252 extending radially inward from the arcuate outer surfaces 238, 239 of the first and second disks 230, 232 to the fiber channel boundary 255, and the groove 254 for fluid, located radially inward from the groove 252 for the fiber. The first disk 230 has an inner side 242 and an outer side 243. The second disk 232 has an inner side 244 and an outer side 245. The hydrostatic bearing 220 also includes an inner component 236 located between the first disk 230 and the second disk 232, providing clearance between them. As shown in FIG. 4A, the width W _C of the fiber slot 252 is constant across the depth of the slot 252, the depth being the position radially inward from the opening 260 defined by the space between the arcuate surfaces 238, 239. For example, the width W _C of the fiber slot 252 is the same. at the opening 260 and at the boundary 255 of the fiber channel. Thus, the pressure drop caused by hydrodynamic flow through the fiber support passage 250 does not change due to the change in bandwidth _WC when the vertical position of the bare optical fiber 14 inside the fiber slot 252 changes.

Instead, as shown in Figure 4B, the hydrostatic bearing 220 has pressure relief zones 270 that comprise a plurality of relief holes 272 extending through the first disc 230 from the inner side 242 to the outer side 243 and/or through the second disc 232 from the inner side 244 to outside 245. In FIG. 4B shows the outer side 243 of the first disc 230 in an embodiment in which the first disc 230 has pressure relief zones 270 with relief holes 272. As shown in FIG. 4B, a plurality of relief holes 272 are azimuthally distributed in the first disc 230. FIG. 4B also illustrates the position of the bare optical fiber 14 relative to the relief holes 272. Some portions of the bare optical fiber 14 are in the fiber slot 252 adjacent to the relief holes 272, and other portions of the bare optical fiber 14 are in the slot 252 adjacent to the inner side 242. In one In an embodiment, the second disc 232 has a similar configuration, containing azimuthally distributed pressure relief zones 270 with relief holes 272. During production, a portion of the flow 251 flowing through the fiber slot 252 may exit the hydrostatic bearing 220 through the relief holes 272. In this embodiment, there will still be flow in the spaces within the fiber slot 252 (eg, flow between the bare optical fiber 14 and the inner sides 242, 244 that define the fiber slot 252), creating the upward and center forces necessary to hold the position uncovered of that optical fiber 14 within the fiber slot 252, as described in more detail above in connection with FIG. 3A.

In the embodiments of FIGS. 4A and 4B, tension compensation (e.g., self-localization of bare optical fiber 14 inward (radially outward) in fiber slot 252 in response to changes in tension applied to bare optical fiber 14) is provided by changes in hydrodynamic flow fraction 251, which flows through the pressure-relieving holes 272. In particular, when the bare optical fiber 14 moves down inside the fiber slot 252 (for example, due to reduced tension), the area of the relief holes 272 under the bare optical fiber 14 increases. If, at a constant flow rate (or pressure) of stream 251, the area of the relief holes 272 under the uncoated optical fiber 14 increases, more of the hydrodynamic flow 251 will pass through the relief holes 272, and a smaller part of the hydrodynamic flow 251 will support (lift) the uncoated optical fiber 14 in fiber slot 252. As a result, the lift force of the flow 251 that acts on the bare optical fiber 14 is reduced, which counteracts the tension-induced upward displacement of the bare optical fiber 14. As the bare optical fiber 14 moves upward in the fiber slot 252, the flow pressure 251 acting on the bare optical fiber 14 is reduced, which counteracts the tension-induced upward displacement. In contrast, when the bare optical fiber 14 moves downward within the fiber slot 252 (eg, due to increased tension), the area of the relief holes 272 under the bare optical fiber 14 decreases. As a result, less hydrodynamic flow 251 passes through relief holes 272 and more hydrodynamic flow 251 supports (raises) the bare optical fiber 14, and the lift force of the flow 251 acting on the bare optical fiber 14 is increased, counteracting the tension-induced displacement of the bare optical fiber. 14 down. As the bare optical fiber 14 moves downward in the fiber slot 252, the force (pressure) of the flow 251 acting on the bare optical fiber 14 increases, counteracting the downward movement caused by the tension.

In one illustrative example, the hydrostatic bearing 220 has a radius of about 3 inches and includes a fiber slot 252 with a constant bandwidth W _C , calculated so that the gaps between a typical bare optical fiber 14 and each inner side 242, 244 are approximately 0.0005 inches, when the bare optical fiber 14 is centered within the fiber slot 352. In this example, the hydrostatic bearing 220 also includes a plurality of relief holes 274 extending from the inner sides 242, 244 through the disks 230, 232 to the outer sides 243, 245. azimuth, have a thickness between the inner sides 242, 244 and the outer sides 243, 245 of about 0.3 inches and are spaced in azimuth, for example, every about 4 degrees. In this illustrative example, when an uncoated optical fiber is drawn with a pull of 200 grams, it will be located inside the vertical fiber slot 252 at the bottom of the discharge holes 274, and when it is drawn with a tension of 10 grams, it will be located inside the vertical fiber slot 252. position at the top of holes 274.

Referring now to Figures 5A-5C, which show a hydrostatic bearing 320. FIG. 5A is a partial side view of the hydrostatic bearing 320, FIG. 5B is a partial front view of the hydrostatic bearing 320, and FIG. 5C is a partial plan view of the hydrostatic bearing 320. Similar to the hydrostatic bearing 220 of Figures 4A and 4B, the hydrostatic bearing 320 has a fiber support channel 350 with a fiber slot 352 extending radially inward from the arcuate outer surfaces 338, 339 of the first and second discs 330, 332 to fiber channel boundary 355, and with fluid slot 353 radially inward of fiber slot 352. The hydrostatic bearing 320 also includes an internal component 336 located between the first disk 330 and the second disk 332, providing clearance between them. As shown in FIG. 5A, the bandwidth WC of the _fiber slot 352 is constant across the depth of the slot 352. Thus, the pressure drop caused by hydrodynamic flow through the fiber support channel 350 does not change due to the change in bandwidth _WC when the vertical position of the uncoated optical fiber is changed. fibers 14 in the fiber slot 352.

Instead, as shown in Figures 5A and 5C, the hydrostatic bearing 320 has pressure relief zones 370 that include relief slots 374 extending into one or both of the inner sides 342, 344 of the discs 330, 332, but unlike the relief ports 272 with fig. 4B, the relief slots 374 only partially extend into the inner sides 342, 344 and do not extend to the outer sides 343, 345 of the discs 330, 332. As illustrated by the outer side 343 of the first disc 330 shown in FIG. 5B, relief slots 374 do not extend through first disk 330 to outer side 343. Instead, as shown in FIGS. arcuate outer surfaces 338, 339, defining a hydrodynamic flow path that is not impeded by the uncoated optical fiber 14. Further, in the embodiments shown in Figures 5A and 5C, the relief slots 374 are angled so that the relief slots 374 extend further into the inner sides 342, 344 at locations closer to the arcuate outer surfaces 338, 339; however, embodiments with straight relief slots 374 (ie, relief slots 374 with a constant cross-sectional area in the radial direction) are also acceptable. During production, since the flow will flow out of the relief slots 374 and thus out of the hydrostatic bearing 320, while in contact with the relief slots 374 for any given pressure of the medium 351 acting in the fiber slot 352, there will be less hydrostatic pressure to support of the bare optical fiber 14 at higher locations in the fiber slot 352 (eg, the closer the bare fiber 14 is to the opening 360 of the fiber support channel 350), so that the bare optical fiber 14 will be less lifted by the flow 351 .

Without wishing to be bound by any theory, when the bare optical fiber 14 is at a higher position within the fiber slot 352, the area of the relief slots 374 under the bare optical fiber 14 is larger and the proportion of hydrodynamic flow 351 that passes through the slot 374, increases. As a result, the part of the hydrodynamic flow 351 that supports (lifts) the bare optical fiber 14 is reduced, and the lift (pressure) from the stream 351 acting on the bare optical fiber 14 is reduced. As bare optical fiber 14 moves upward in slot 352 for fiber 352, the force (pressure) of flow 351 acting on bare optical fiber 14 is reduced, which counteracts the upward movement caused by tension. In contrast, when the bare optical fiber 14 is at a lower position in the fiber support channel 350, the area of the relief slots 374 under the bare optical fiber 14 is smaller, and the proportion of hydrodynamic flow 351 that passes through the relief slots 374 is reduced. As a result, the part of the hydrodynamic flow 351 that supports (lifts) the uncoated optical fiber 14 increases, and the lift (pressure) from the flow 351 acting on the uncoated optical fiber 14 increases. As the bare optical fiber 14 moves downward in the fiber slot 352, the force (pressure) of the flow 351 acting on the bare optical fiber 14 increases, which counteracts the downward movement caused by the tension. Thus, when the tension of the bare optical fiber 14 is changed, the bare optical fiber 14 is still held within the fiber slot 352, even in embodiments in which the inner sides 342, 244 of the fiber slot 352 are parallel to each other, since when the bare optical fiber 14 moves upward (e.g., radially outward) within the fiber slot 352, more flow exits through the relief slots 374, thereby reducing the pressure drop under the bare optical fiber 14, which causes the bare optical fiber 14 to stop moving upward in the fiber slot 352.

As one illustrative example, hydrostatic bearing 320 has a radius of about 3 inches and includes a fiber slot 352 having a constant bandwidth W _C , calculated so that the spacing between a typical bare optical fiber 14 and each inner side 342, 344 is about 0.0005 inch when the bare optical fiber 14 is centered within the fiber slot 352. This example hydrostatic bearing 320 also includes a plurality of relief slots 374 extending into the inner sides 342, 344 of the discs 330, 332 and having a height of about 0.025 inches in the radial direction, a width of 0.015 inches in the azimuth, extending deep into the inner sides 342, 344 at the arcuate outer surfaces 338, 339 (eg, deepest point) by about 0.01 inch, and spaced in azimuth, for example, every about 4 degrees. In this illustrative example, when an uncoated optical fiber is drawn with a tension of 200 grams, it is located inside the vertical fiber slot 352 at the bottom of the discharge slots 374, and when it is drawn with a tension of 10 grams, it is located inside the vertical fiber slot 352 at the top. unloading slots 374.

Referring now to figures 6A and 6B showing a hydrostatic bearing 420. FIG. 6A is a partial side view of a hydrostatic bearing 420, and FIG. 6B is a partial front view of the hydrostatic bearing 420. Similar to the hydrostatic bearings 120, 220, and 320 of Figures 3A-5C, the hydrostatic bearing 420 includes a fiber support channel 450 having a fiber groove 452 extending radially inward from the arcuate outer surfaces 438, 439 of the first and second disks 430, 432 to fiber channel boundary 455, and a fluid slot 454 radially inward from fiber slot 452. The hydrostatic bearing 420 also has an internal component 436 located between the first disk 430 and the second disk 432, providing clearance between them. As shown in FIG. 6A, the bandwidth WC of the _fiber slot 452 is constant across the depth of the slot 452. Thus, the pressure drop caused by hydrodynamic flow through the fiber support channel 450 does not change due to the change in bandwidth _WC when the vertical position of the uncoated optical fiber is changed. fibers 14 in the fiber slot 452.

Instead, as shown in Figures 6A and 6B, the hydrostatic bearing 420 includes pressure relief zones 470 that comprise one or more porous material regions 476 located within the inner sides 442, 444 of the first and second discs 430, 432 at the radial position of the slot 452 for fibers of the fiber support channel 450 so that flow can exit through the inner sides 442, 444 of the fiber support channel 450 through the outer sides 443, 445 of the hydrostatic bearing 430. The outer side 443 of the first disc 430 is shown in FIG. 6b. Said one or more areas of porous material 476 may contain a porous metal environment, such as is formed during the sintering of metal layers, when the pores are trapped in the metal during sintering. Such porous metal media are available, for example, from Applied Porous Technologies, Tariffville, Conn., USA. Other embodiments of porous media include ceramic porous media. While not wishing to be bound by theory, because flow will flow from fiber support channel 450 through areas of porous material 476, less hydrodynamic flow will flow through fiber support channel 450 and thus less hydrodynamic force (pressure) will support bare optical fiber 14 as it travels upward (radially outward) in channel 450 to support the fiber. Therefore, if the tension on the bare optical fiber 14 is reduced and the bare optical fiber 14 is induced to move upward, it will still remain inside the fiber slot 452 even if the inner sides 442, 444 forming the fiber slot 452 are parallel to each other, as shown in Fig. fig. 6A. As bare optical fiber 14 moves upward (eg, radially outward) within fiber slot 452, more flow 451 exits through one or more regions of porous material 476, thereby reducing the pressure drop across bare optical fiber 14 and causing bare optical fiber 14 to stop moving. upwards (eg, radially outward) in the fiber slot 452. As the uncoated optical fiber 14 moves upward in the fluid slot 452, more of the hydrodynamic flow 451 passes through the regions of porous material 476, and a smaller portion of the hydrodynamic flow 451 supports (lifts) the uncoated optical fiber 14. As a result, the lift force generated by the flow 451 ( pressure) acting on the bare optical fiber 14 will decrease, which counteracts the upward displacement of the bare optical fiber 14 caused by tension. As the bare optical fiber 14 moves upward in the fiber slot 452, the force (pressure) of the flow 451 acting on the bare optical fiber 14 is reduced, counteracting the upward movement caused by the tension. Similarly, as the tension increases, the bare optical fiber 14 moves downward in the fiber slot 452. As the bare optical fiber 14 moves down in the fiber slot 452, less of the hydrodynamic flow 451 passes through regions of porous material 476 and more of the hydrodynamic flow 451 supports (raises) the bare optical fiber 14, providing increased lift (pressure) that counteracts tension-induced downward displacement. As the bare optical fiber 14 moves downward in the fiber slot 452, the force (pressure) of the flow 451 acting on the bare optical fiber 14 increases, counteracting the downward movement caused by tension.

Referring again to Figures 1-6B, it should be understood that the optical fiber system 100 may comprise hydrostatic bearings having the various configurations described above, and in addition, any individual hydrostatic bearing of the optical fiber system 100 may comprise any combination of these. configurations. During manufacture, each of the hydrostatic bearings 120, 220, 320, 420 is configured to achieve tension compensation and to hold the uncoated optical fiber 14 in the fiber slot 152, 252, 352, 452. However, rapid vertical (e.g., radial) position fluctuations bare optical fiber 14 inside the fiber slot 152, 252, 352, 452 may cause the bare optical fiber 14 to exit the slot 152, 252, 352, 452. 160, 260, 360, 460, and rapid movement radially downward may cause the bare optical fiber 14 to mechanically contact or enter the fluid slot 154, 254, 354, 454. In particular, the bare optical fiber 14 may contact the fluid slot 154, 254, 354, 454 when the width of the slot 154, 254, 354, 454 is less than the diameter of the bare optical fiber 14, and may enter the fluid slot 154, 254 , 354, 454 when the width of the slot 154, 254, 354, 454 is greater than the diameter of the bare optical fiber 14.

Without wishing to be bound by any theory, it can be believed that the rapid vertical movement of an uncoated optical fiber can be caused by rapid changes in tension (for example, decrease or increase), changes in the diameter of the uncoated optical fiber, and vibrations of the uncoated optical fiber, which can lead to an increase in the number hydrostatic bearings in embodiments of the system for producing optical fiber. Without wishing to be bound by any theory, it can be assumed that sections of optical fiber between hydrostatic bearings (e.g., different "fiber columns") can form coupled oscillators having different natural frequencies, which can be amplified by increasing the number of "fiber columns" along the pull path. In addition, when the vertical position of the bare optical fiber rapidly decreases in the fiber slot due to increased tension, the downward forces acting on the bare optical fiber may temporarily increase (e.g., rise) due to inertial effects, further enhancing the rapid height change. .

Rapid vertical movement is a particular problem for hydrostatic bearings that have cutouts at their inlets and outlets (i.e., cross cuts in the fiber support channel, designed to allow uncoated optical fiber to enter and exit the fiber support channel at an angle ninety degrees), as, for example, in the hydrostatic bearing embodiments described in US Pat. No. 7,937,971, the entire contents of which are incorporated herein by reference. Without wishing to be bound by any theory, it can be assumed that the sections of bare optical fiber located immediately before the entrance of the hydrostatic bearing and immediately after the exit of the hydrostatic bearing are rigidly connected by axial rigidity with the section of bare optical fiber located in the channel for supporting the fiber, but no lifting force acts on these exposed portions of the bare optical fiber, since these portions are outside the hydrostatic bearing and do not experience the lifting action of the hydrodynamic flow. This increases the effective fiber inertia to lift ratio for the bare optical fiber portion in the fluid slot of the hydrostatic bearing, and thus increases the likelihood that the bare optical fiber will make mechanical contact and/or enter the fluid slot of the channel for fiber support.

Mechanical contact between an uncoated optical fiber and a fluid slot (e.g., mechanical contact between an uncoated optical fiber and portions of the inner walls that define a fluid slot) can cause damage to an uncoated optical fiber, resulting in reduced fiber strength and, in some cases, breakage. fibers. Even if the bare optical fiber does not break immediately, mechanical contact with the fluid slot often causes cracks on the surface of the bare optical fiber that are large enough to break the optical fiber during a subsequent tensile test. Bare optical fiber breaks will result in a shortened fiber length (making it less desirable for customers) and the need to stop and restart the fiber drawing process. In addition, if the minimum commercially available length was not reached during the tensile strength test, the entire fiber length to break may be useless. It is also undesirable that tension fluctuations cause the optical fiber to move downward into the fluid slot. The fluid slot most often has a constant width between opposite inner surfaces, meaning that there is no change in lift (pressure) acting on the bare optical fiber as the bare optical fiber moves deeper into the fluid slot. As a result, when an uncoated optical fiber enters the fluid slot, there is a possibility that the tension or tension fluctuation that caused the fiber to move downward into the fluid slot will cause the fiber to come into contact with the bottom surface of the fluid slot. Thus, it is desirable to modify the hydrostatic bearing in such a way as to reduce the likelihood of an uncoated optical fiber entering the fluid slot or making mechanical contact with it.

Figures 7A-11B depict hydrostatic bearing embodiments that are capable of reducing the likelihood that an uncoated optical fiber will enter or mechanically contact the fluid slot of the fiber support channel. For example, in the embodiments of Figures 7A-11B, the hydrostatic bearing has alternate fluid slot and/or pressure relief zone configurations that are capable of increasing fluid dynamic resistance to downward displacement caused by tension fluctuations. The downward displacement resistance corresponds to the work required to move an uncoated optical fiber per unit distance in a radially inward direction to a deeper position in the fiber slot. As work per unit distance increases, the tension fluctuation required to move an uncoated optical fiber from its stabilized equilibrium position to a deeper position in the fiber slot increases. In other words, as work per unit distance increases in the downward direction, the downward displacement due to tension caused by a given tension fluctuation decreases, providing greater consistency in the position of an uncoated optical fiber in a fiber slot and reducing the likelihood that an uncoated optical fiber will fall into a fiber slot. fluid.

In one embodiment, the work required to move a fiber per unit distance into a fiber slot of a given depth, a given width at the opening, and a given width at the fiber channel boundary is increased compared to a reference fiber slot configuration with inner surfaces converging under constant angle (e.g., a fiber slot configuration of the type shown in FIG. 3A, which shows tapered inner surfaces 142, 144 for fiber slot 152 having a constant slope or angle between aperture 160 and fiber channel boundary 155), and having such the same depth, the same width at the hole, and the same width at the edge of the fiber channel. Without wishing to be bound by theory, if the average work required to move an uncoated optical fiber per unit distance from the top to the bottom of the fiber slot is greater than the instantaneous kinetic energy of the uncoated optical fiber as it moves downward in the fiber slot ( for example, due to the downward displacement caused by tension described above), an uncoated optical fiber will not enter or mechanically contact the fluid slot.

Referring, for example, to FIG. 12A. In FIG. 12A shows a plot of 50 force profiles for two fiber slot designs (S ₁ fiber slot and S ₂ fiber slot). The force profile is a functional relationship between the vertical (eg, radial) position of an uncoated optical fiber in a fiber slot and the lifting force of the rising fluid acting on the uncoated optical fiber. Line 55 shows the force profile for fiber slot S ₁ and line 60 shows the force profile for fiber slot S ₂ . The configurations of slot S ₁ and fiber slot S ₂ are shown in FIG. 12b. The lifting force is a force corresponding to a portion of the hydrodynamic flow that acts on an uncoated optical fiber in the fiber slot S ₁ or S ₂ . For purposes of illustration, the fiber slot S ₁ , fiber slot S ₂ and tension were calculated such that the hydrodynamic lift force acting on the bare optical fiber is 10 g when the bare optical fiber is at the top of the fiber slot S ₁ or at the top of the slot S ₂ for a fiber, and the hydrodynamic lift force acting on an uncoated optical fiber when it is at the bottom of slot S ₁ or at the bottom of slot S ₂ was 200 g.

The top of the fiber slot corresponds to the opening of the fiber slot (eg, holes 160, 260, 360, and 460 in Figures 3A, 4A, 5A, and 6A, respectively). The bottom of the fiber slot corresponds to a fiber channel boundary that corresponds to the interface between the fiber slot and the fluid slot (eg, fiber channel boundaries 155, 255, 355, and 455 of Figures 3A, 4A, 5A, and 6A, respectively). The position of the fiber in Fig. 12A is referred to as "fibre slot depth" and is measured from the top of the fiber slot to the bottom of the fiber slot. The direction from the top center of the fiber slot to the center of the bottom of the fiber slot is the depth direction. For illustrative purposes, the position of the fiber in the fiber slot is shown in conventional units. The principles underlying the performance of the exemplary fiber slots S ₁ and S ₂ disclosed herein are generally applicable to fiber slots of any depth or width, as well as to hydrodynamic lift modes other than the exemplary 10 g to 200 g modes shown in FIG. . 12A.

The fiber slot S ₁ is shown in FIG. 12B with a solid line and has a configuration of the type shown in FIG. 3A. The inner sides of the groove S ₁ for the fiber converge on a cone at a constant angle or a constant slope from top to bottom. The bottom of the fiber slot S ₁ is at the inner end point of the cone, which corresponds to the boundary of the fluid channel and the entrance to the fluid slot. The fiber slot S ₂ is shown in FIG. 12B with a dashed line and includes inner sides with a non-constant angle or a non-constant slope from top to bottom. More precisely, the fiber slot S ₂ comprises an upper section S _2A adjacent to the top and a lower section S _2B adjacent to the bottom. Sections S _2A and S _2B each taper at a constant angle or have a constant slope, but this constant angle and constant slope are different for sections S _2A and S _2B . The force profiles for sections S _2A and S _2B are shown in FIG. 12A by lines 65 and 70, respectively. For purposes of illustration, the fiber slots S ₁ and S ₂ share a common fluid slot FS.

The portions of the inner sides of the fiber slot S ₂ corresponding to the sections S _2A and S _2B are referred to herein as the wall zones of the fiber slot S ₂ . The inner side of the fiber slot S ₂ comprises a wall zone corresponding to section S _2A and a wall zone corresponding to section S _2B , wherein the wall zone of section S _2A differs in angle and taper slope from the wall zone of section S _2B . For purposes of description and comparison, the angle and slope of the cone are defined in terms of magnitude relative to the center axis of the fiber slot. The central axis extends in the radial direction and is centered in the width direction of the fiber slot. Counted relative to the central axis, the taper angle of the section wall zone S _2A is greater than the taper angle of the section wall zone S _2B , and the slope of the section wall zone S _2A is greater than the slope of the section wall zone S _2B .

The fiber slots S ₁ and S ₂ have the same height (eg, the same distance between the fiber slot opening (top) and the fluid slot boundary (bottom)), and the same width at the top and bottom positions. Fiber slots S ₁ and S ₂ are configured such that the upward hydrodynamic force acting on the bare optical fiber is the same for slots S ₁ and S ₂ at the top (10 g) and bottom (200 g) (see Fig. 12A) . However, due to the different shape of the inner sides, the lifting hydrodynamic force acting on the bare optical fiber at the intermediate positions between top and bottom is different for the fiber slots S ₁ and S ₂ . In particular, for a given intermediate position, the upward hydrodynamic force acting on the bare optical fiber is greater for the fiber slot S ₂ than for the fiber slot S ₁ . Because the lifting hydrodynamic force opposes downward movement of the bare optical fiber, the work required to move the bare optical fiber deeper into the fiber slot will be greater for slot S ₂ than for slot S ₁ . The total work required to cause the bare optical fiber to move from the top of the fiber slot to the bottom of the fiber slot against the upward hydrodynamic force is determined by the area under the plotted fiber slot position vs. the upward hydrodynamic force against downward movement of the bare optical fiber. In the case of fiber slot S ₁ , the work required to move an uncoated optical fiber from the top of the fiber slot to the bottom of the fiber slot corresponds to the area of the triangle bounded by the force profile 55 and the two coordinate axes. For fiber slot S ₂ , the work required to move an uncoated optical fiber from the top of the fiber slot to the bottom of the fiber slot corresponds to the area of the polygon given by force profiles 65 and 70 for sections S _2A and S _2B , respectively, and two coordinate axes.

Because the area for fiber slot S ₂ is larger than the area for fiber slot S ₁ , more work is required to move an uncoated optical fiber from the top of fiber slot S ₂ to the bottom of slot S ₂ than would be required to move an uncoated optical fiber. from the top of fiber slot S ₁ to the bottom of slot S ₁ . Thus, the position of the bare optical fiber in the fiber slot S ₂ is more stable, and its mechanical contact with the fiber slot or the fluid slot is less likely than in the case of the fiber slot S ₁ when the fiber is subjected to a downward displacement caused by a momentary an increase in tension.

Thus, without wishing to be bound by any theory, we can assume that due to the shape of the force profile (functional relationship between the position of the fiber in the radial direction and the upward hydrodynamic force) in the groove S ₂ for a fiber in any vertical position between the hole and at the boundary of the fluid channel in fiber slots S ₁ and S ₂ , the lift force on an uncoated optical fiber generated by the hydrodynamic flow inside the fiber slot will be greater in the case of slot S ₂ than in the case of slot S ₁ , and therefore the integral force over distance (ie, the work that corresponds to the area under the force profile) will be greater in fiber slot S ₂ than in slot S ₁ . Thus, more work will be required to move an uncoated optical fiber from the hole to the fluid channel boundary in the fiber slot S ₂ than in the fiber slot S ₁ . In other words, slot S ₂ will dissipate more of the instantaneous kinetic energy of the bare optical fiber as it moves deeper into the fiber slot before the fiber reaches the fluid slot, so that the bare optical fiber in the fiber slot S ₂ is less likely to enter or mechanically contact the fluid slot than the bare optical fiber in the fiber slot S ₁ .

Further, also without being limited by theory, the lifting force acting on the optical fiber caused by the hydrodynamic flow through the fiber support channel is a dissipative force, so that the energy required to move the bare optical fiber lower in the fiber slot is path dependent. Each of the hydrostatic bearings of Figures 7A-11B, described below, is designed to provide a functional dependency of fiber position on upward hydrodynamic force that will increase the work required to cause an uncoated optical fiber to move a predetermined distance in a downward direction, compared to a slot configuration. for fluid converging at a constant angle, or constant slope, from top to bottom and with identical widths at top and bottom. Thus, by using the hydrostatic bearings of Figures 7A-11B, the kinetic energy required to get an uncoated optical fiber into or into mechanical contact with a fluid slot can be increased (for example, by about 20%, or by about 30%, or about 50% or about 60%) when compared to hydrostatic bearing designs having a purely linear force profile (defined as a force profile having a constant slope from the top of the fiber slot to the bottom of the fiber slot, such as the force profile fiber slot S ₁ shown in Figure 12A). In addition, although the fiber slot S ₂ of Figures 12A and 12B is depicted as containing a force profile with two slopes, fiber slot configurations containing three, four, or more line segments on the force profile (e.g., three, four or more slopes or constrictions) are acceptable. in the force profile), or having a continuously changing slope of the convex force profile. In other words, as the magnitude of the slope of the force profile increases monotonically at locations inside the fiber slot approaching the fiber channel boundary, more work is required for the uncoated optical fiber to enter or come into mechanical contact with the fluid slot.

The principles resulting in increased work for downward displacement, better fiber position stability, and less tendency for fiber to mechanically contact the fluid slot described for fiber slot S ₂ as compared to fiber slot S ₁ apply to fiber slot configurations having a convex force profile. A convex shape means a shape that increases the area under the force profile compared to a purely linear force profile, with the same forces at the top and bottom of the fiber slot. Convex force profiles may include linear segments, curved segments, or a combination of linear and curved segments. Compared to a purely linear force profile, a convex force profile contains a linear segment or a curved segment whose slope is less than the slope of a purely linear force profile. For the purposes of describing force profiles or force profile segments, slope refers to the slope of a force profile or force profile segment on a graph of fiber location in a fiber slot (expressed as a radial position where the top of the fiber slot has a greater radial position than the bottom of the fiber slot ( for example, as shown in Fig. 12A)) depending on the lift force. The amount of slope refers to the absolute value of the slope. The steeper the force profile or segment of the force profile, the greater the amount of slope (regardless of the sign of the slope). For line segments, the slope refers to the slope of the segment. For curved segments, the slope refers to the slope of the tangent to the curved segment.

The slope of the line segment or tangent to the curved segment can be defined as the angle of the line segment or tangent to the curved segment about the center axis of the fiber slot. The angle of a linear segment or a tangent to a curved segment is greater than 0º, or greater than 0.1º, or greater than 0.2º, or greater than 0.3º, greater than 0.4º, or lies in the range from 0º to 10º, or in the range from 0.1º to 9º, or in the range from 0.2º to 8º, or in the range from 0.3º to 7º, or in the range from 0.4º to 5º.

In FIG. 12C shows examples of convex force profiles containing line segments, and FIG. 12D shows examples of convex force profiles containing curved segments. In Figures 12C and 12D, force profile 75 is a purely linear force profile given as a reference. A purely linear force profile is a non-convex force profile. In FIG. 12C, force profiles 76 and 77 are convex force profiles and have the same force values at the top and bottom of the fiber slot as force profile 75. Convex force profile 76 contains two linear segments (two slopes or two tapers) and convex force profile 77 contains three line segments (three slopes or three tapers). The area under the convex force profile 77 is greater than the area under the convex force profile 76, which is greater than the area under the purely linear force profile 75. The work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is greater for a convex profile. force profile 77 than for a convex force profile 76, and the work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is greater for a convex force profile 76 than for a purely linear force profile 75. The following embodiments include force profiles , containing four or more line segments.

In one embodiment, the convex force profile comprises two or more linear segments, with one of the linear segments having a slope less than the slope of a purely linear force profile, with the same force at the top and bottom of the fiber slot as for the convex profile. force, and the other of the linear segments has a slope greater than the slope of a purely linear force profile, with the same force at the top and bottom of the fiber slot as for a convex force profile. In one embodiment, a line segment whose slope is less than the slope of a purely linear force profile is closer to the bottom of the fiber slot than a line segment whose slope is greater than the slope of a purely linear force profile. In one embodiment, a line segment whose slope is less than the slope of a purely linear force profile is closer to the top of the fiber slot than a line segment whose slope is greater than the slope of a purely linear force profile.

In convex force profiles containing several line segments, the angle difference between two adjacent line segments is greater than 0º, or greater than 0.1º, or greater than 0.2º, or greater than 0.3º, greater than 0.4º, or lies in the range from 0º to 10º, or in the range of 0.1º to 9º, or in the range of 0.2º to 8º, or in the range of 0.3º to 7º, or in the range of 0.4º to 5º.

Fig. 12D shows convex force profiles 78 and 79. Convex force profiles 78 and 79 are curved force profiles. The area under the force 79 convex profile is greater than the area under the force 78 convex profile, which is greater than the area under the purely linear force 75 profile. The work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is greater for a convex profile force 79 than for a convex force profile of 78, and the work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is greater for a convex force profile of 78 than for a purely linear force profile of 75.

In one embodiment, the convex force profile is a curved force profile that contains two or more points, where the tangent to one of the points has a slope less than the slope of a purely linear force profile, with the same force at the top and bottom of the fiber slot, as for a convex force profile, and the tangent to the other point has a slope greater than that of a purely linear force profile, with the same force at the top and bottom of the fiber slot as for a convex force profile. In one embodiment, the point at which the slope is less than the slope of the purely linear force profile is closer to the bottom of the fiber slot than the point at which the slope is greater than the slope of the purely linear force profile. In another embodiment, the point at which the slope is less than the slope of the purely linear force profile is closer to the top of the fiber slot than the point at which the slope is greater than the slope of the purely linear force profile.

In a convexly curved force profile having at least two tangents differing in inclination at different points of the force profile, the difference between the angles of said at least two tangents is greater than 0º, or greater than 0.1º, or greater than 0.2º, or greater than 0 ,3º, greater than 0.4º, or lies in the range from 0º to 10º, or in the range from 0.1º to 9º, or in the range from 0.2º to 8º, or in the range from 0.3º to 7º, or in the interval from 0.4º to 5º.

Figures 12E and 12F show examples of non-convex force profiles. One example of a non-convex force profile is the purely linear force profile 75. FIG. 12E shows non-convex force profiles 81 and 82 containing two and three line segments, respectively. The area under the non-convex force profile 82 is less than the area under the non-convex force profile 81, which is less than the area under the purely linear force profile 75. The work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is less for the non-convex force profile 82 than for a non-convex force profile of 81, and the work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is less for a non-convex force profile of 81 than for a purely linear force profile of 75.

Fig. 12F shows non-convex force profiles 83 and 84 that contain one or more curved segments. The work required to move the fiber from the top to the bottom of the fiber slot in the case of a non-convex force profile is less than the work required to move the fiber from the top to the bottom of the fiber slot in the case of a convex force profile, with the same lift at the top of the fiber slot for convex and non-convex force profiles and the same lift at the bottom of the fiber slot for convex and non-convex force profiles.

The area under the non-convex force profile 84 is less than the area under the non-convex force profile 83, which is less than the area under the purely linear force profile 75. The work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is less for the non-convex force profile 84 than for 83 non-convex force profile, and the work required to move the fiber from the top of the fiber slot to the bottom of the fiber slot is less for a non-convex 83 force profile than for a purely linear 75 force profile.

Fig. 7A-11B and 13A-14 show fiber slot configurations providing convex force profiles. Referring to Figures 7A and 7B, the hydrostatic bearing 520 is capable of increasing the amount of power required to move the bare optical fiber 14 from the opening 560 to the fiber channel boundary 555. In particular, in FIG. 7A is a partial side view of a hydrostatic bearing 520, and FIG. 7B is a partial front view of the hydrostatic bearing 520 showing the outer side 543 of the first disc 530. Similar to the hydrostatic bearing 120 of Figures 3A and 3B, the hydrostatic bearing 520 includes a fiber support channel 550 with a fiber slot 552 extending radially inward from the arcuate outer surfaces 538, 539 of the first and second discs 530, 532 to the fiber channel boundary 555, and a fluid slot 554 radially inward from the fiber slot 552. The hydrostatic bearing 520 also includes an internal component 536 located between the first disk 530 and the second disk 532, providing clearance between them.

As shown in FIG. 7A, similar to the hydrostatic bearing 120 of FIGS. 3A and 3B, the fiber slot 552 width W _C varies with the depth of the fiber slot 552, decreasing as the bare optical fiber 14 approaches the fiber channel boundary 552. However, the fiber slot 552 is delimited by two slot wall areas 542a, 542b, 544a, 544b on each inner side 542, 544 that taper at different angles to the Z-axis (an up/down radial axis that defines the depth of the uncoated optical fiber 14 in the slot 552). for fiber). The first slot wall zones 542a, 544a extend from the arcuate outer surfaces 538, 539 to the second slot wall zones 542b, 544b, respectively, which extend from the first slot wall zones 542a, 544a to the fiber channel boundary 555. Further, the first slot wall zones 542a, 544a on each inner side 542, 544 are inclined at a first angle, and the second slot wall zones 542b, 544b on each inner side 542, 544 are inclined at a second angle, the first angle to the Z-axis being greater than second corner. In other words, the amount of inclination of the first zone 542a, 544a of the slot walls is greater than the amount of the inclination of the second zone 542b, 544b of the slot walls.

As an illustrative example, in the embodiments of fiber slot 152 of Figures 3A and 3B and fiber slot 552 of Figures 7A and 7B having an equivalent width W _C at their respective apertures 160, 560 and an equivalent width W _C at their respective the fiber channel boundaries 155, 555, hydrodynamic flow within the fiber slots 152, 552 induces equivalent lift forces at the apertures 160, 560 and induces equivalent lift forces at the fiber channel boundaries 155, 555. However, due to the plurality of slot wall zones 542a, 542b, 544a, 544b and their slopes that define the fiber slot 552, the wall zones closer to the fiber channel boundary 555 (e.g., the second slot wall zones 542b, 544b) have smaller slopes. , the hydrodynamic flow causes a higher lift force at all points of the fiber slot 552 between the opening 560 and the fiber channel boundary 555 and therefore more work is required for the bare optical fiber 14 passing through the fiber slot 552 to come into mechanical contact or included in the groove 554 for the fluid than in the case of the groove 152 for the fiber. This increased amount of work is a consequence of the convex force profile associated with fiber slot 552 compared to the purely linear force profile of fiber slot 152. In addition, although two slot wall zones 542a, 542b, 544a, 544b are shown in the figures, it should be understood that any number of slot wall zones are acceptable in which each successively lower (deeper, more radially inward) wall zone has a smaller amount of slope. .

Referring now to Figures 8A and 8B, which depict a hydrostatic bearing 620 capable of increasing the amount of energy required to move bare optical fiber 14 from opening 660 to fiber channel boundary 655. In particular, FIG. 8A shows a partial side view of a hydrostatic bearing 620, and FIG. 8B is a partial front view of the hydrostatic bearing 620 showing the outer side 643 of the first disc 630. The hydrostatic bearing 620 includes a fiber support channel 650 comprising a fiber groove 652 extending radially inward from the arcuate outer surfaces 638, 639 of the first and second discs 630, 632 to a fiber channel boundary 655; and a fluid slot 654 extending radially inward from the fiber slot 652. The hydrostatic bearing 620 also includes an internal component 636 located between the first disk 630 and the second disk 632, providing clearance between them. As shown in FIG. 8A, the width W _C of the fiber slot 652 is constant throughout the depth of the fiber slot 652. For example, the width W _C of the fiber slot 652 is the same at the opening 660 and at the boundary 655 of the fiber channel.

Further, the hydrostatic bearing 620 includes pressure relief regions 670 that include a plurality of relief holes 672 extending from one or both of the inner sides 642, 644 of the fiber support channel 650 through the outer sides (a single outer side 643 is shown). As shown in FIG. 8B, these relief holes 672 are all spaced apart in azimuth so that portions of the uncoated optical fiber 14 inside the hydrostatic bearing 620 are adjacent to the relief holes 672, and other portions of the uncoated optical fiber 14 are adjacent to the inner sides 642, 644, driving slot 652 for fiber 652. During production, a portion of the hydrodynamic flow 651 flowing through fiber slot 652 may exit hydrostatic bearing 620 through first and second disks 630, 632, flowing through relief holes 672. In this embodiment, still occurs flow in spaces in fiber slot 652 (e.g., flow in spaces between bare optical fiber 14 and inner sides 642, 644 defining fiber slot 652) creating an upward and centering force to maintain bare optical fiber 14 within fiber slot 652 .

Further, the discharge holes 672 shown in FIG. 8B are of variable azimuth width such that each relief opening 672 is wider at the top (eg, closer to the arcuate outer surfaces 638, 639) and narrower at the bottom (eg, closer to the fiber channel boundary 655). While not wishing to be bound by any theory, relief openings 672 having a variable azimuth width that is greater at the top (eg, closer to the arcuate outer surfaces 638, 698) than at the bottom (eg, closer to the fiber channel boundary 655 ) cause the lift due to hydrodynamic flow at all points in the fiber slot 652 between the opening 660 and the fiber channel boundary 655 to be greater than the lift due to relief holes having a constant azimuth width (e.g., relief holes 272 of Figure 4B), and therefore more work is required to move the uncoated optical fiber 14 down in the fiber slot 652 and to make mechanical contact or enter the fluid slot 654.

As one illustrative example, the hydrostatic bearing 620 may have a radius of about 3 inches and include a slot 652 for a constant width fiber W _C . This example hydrostatic bearing 620 includes a plurality of relief holes 672 that extend from the inner sides 642, 644 through the discs 630, 632 to the outer sides (a single outer side 643 is shown in FIG. 8B) and are about 0.030 inches high in the radial direction, about 0.006 inches in azimuth from above and converge to a point below. Further, the thickness between the inner sides 642, 644 and the outer sides is about 0.3 inches, and the relief holes 672 are placed in azimuth about every 4 degrees. In this illustrative example, when an uncoated optical fiber is drawn with a pull of 200 grams, it will be located inside the fiber slot 652 in the same vertical position as the bottom of the discharge holes 674, and when it is pulled with a pull of 10 grams, it will be inside the slot. 652 for fiber in the same vertical position as the top of the discharge holes 674.

Referring now to Figures 9A-9C showing a hydrostatic bearing 720 capable of increasing the amount of energy required to move bare optical fiber 14 from opening 760 to fiber channel boundary 755. In FIG. 9A is a partial side view of a hydrostatic bearing 720, FIG. 9B is a partial front view of the hydrostatic bearing 720 showing the outer side 743 of the first disk 730, and in FIG. 9C is a partial plan view of the hydrostatic bearing 720. Similar to the hydrostatic bearing 320 of Figures 5A-5C, the hydrostatic bearing 720 has a fiber support channel 750 with a fiber slot 752 extending radially inward from the arcuate outer surfaces 738, 739 of the first and second disks 730, 732 to the fiber channel boundary 755, and a fluid slot 754 located radially inward of the fiber slot 752. Hydrostatic bearing 720 also includes an internal component 736 located between the first disk 730 and the second disk 732, providing clearance between them. As shown in FIG. 9A, the width W _C of the fiber slot 752 is constant throughout the depth 762 of the fiber slot.

Further, similar to the hydrostatic bearing 320 of FIGS. 5A-5C, the hydrostatic bearing 720 includes pressure relief zones 770 that include relief slots 774 extending into the inner sides 742, 744 of the disks 730, 732 while being azimuthally spaced between the fiber channel boundary 755 and arcuate outer surfaces 738, 739, providing a fluid path that is not obstructed by uncoated optical fiber 14. However, unlike the discharge slots 374 of Figures 5A-5C, the discharge slots 774 have a plurality of segments 774a, 774b, each tapering under angles to the Z-axis (eg, an up/down radial axis corresponding to the depth in the fiber slot 752 along which the bare optical fiber 14 can move in the fiber slot 752). The first discharge slot segments 774a extend from the arcuate outer surfaces 738, 739 to the second discharge slot segments 774b. Second discharge slot segments 774b extend from first discharge slot segments 774a to fiber channel boundary 755. Further, the first discharge slot segments 774a are inclined at a first angle, and the second discharge slot segments 774b are inclined at a second angle, the first angle to the Z-axis being greater than the second angle. In other words, the slope of the segments 774a of the first discharge slot is greater than the slope of the segments 774b of the second discharge slot.

During production, since flow 751 will flow out of the relief slots 774 and thus out of the hydrostatic bearing 720 when it comes into contact with the relief slots 774 at any given fluid pressure acting in the fiber slot 752, the hydrodynamic pressure to support there will be less uncoated optical fiber 14 at higher locations within fiber slot 752 (eg, positions of uncoated optical fiber 14 that are closer to opening 760 of fiber support channel 750). In addition, since the relief slots 774 comprise a plurality of segments 774a, 774b, the slope of which decreases as the fiber channel boundary 755 is approached, the lift forces generated by hydrodynamic flow between the opening 760 at the arcuate outer surfaces 738, 739 and the fiber channel boundary 755 are larger than unload slots of the same size but with a constant slope (e.g., unload slots 374 of Figures 5A-5C), so more work is required to get bare optical fiber 14 to pass through fiber slot 752 in a downward direction for mechanical contact or entry into the fluid slot 754. In addition, although two relief slot segments 774a, 774b are shown in the figures, it should be understood that any number of relief slot segments are acceptable in which each successively lower (deeper) segment has a smaller slope (e.g., relief slot segments successively approaching the boundary 755 channels for fiber).

As one illustrative example, hydrostatic bearing 720 has a radius of about 3 inches and includes a fiber slot 752 with a constant bandwidth W _C , calculated so that the gaps between a typical bare optical fiber 14 and each inner side 742, 744 are approximately 0.0005 inches when the bare optical fiber 14 is centered on the fiber slot 752. A typical hydrostatic bearing 720 also includes a plurality of relief slots 774 that extend into the inner sides 742, 744 of the discs 730, 732 and are approximately 0.025 inches high in the radial direction, 0.015 inches wide in the azimuth, and extend deep into the inner sides 742, 744 of the discs 730, 732. arcuate outer surfaces 738, 739 (eg, deepest point) by about 0.01 inch and spaced apart by about every 4 degrees in azimuth. In addition, the first segment 774a of the relief slot 774 extends radially inward from the arcuate outer surfaces 738, 739 to a depth of 0.1 inches at an angle of 2.6 degrees (to the Z axis), and the second segment 774b of the relief slot extends radially inward from the first segment 774a discharge slot to the fiber channel boundary 755 at an angle of approximately 0.6 degrees (to the Z-axis). In this illustrative example, moving an uncoated optical fiber from opening 760 of fiber slot 752 to fiber channel boundary 755 would require 1.8 times more work than a fluid slot having close-sized relief slots with a single angle (e.g., discharge slots 374 of Figures 5A-5C).

Referring now to Figures 10A and 10B, a hydrostatic bearing 820 is shown capable of increasing the amount of power required to move bare optical fiber 14 from opening 860 to fiber channel boundary 855. In FIG. 10A is a partial side view of a hydrostatic bearing 820, and FIG. 10B is a partial front view of the hydrostatic bearing 820 showing the outer side 843 of the first disk 830. Similar to the hydrostatic bearings 420 of Figures 6A and 6B, the hydrostatic bearing 820 includes a fiber support channel 850 having a fiber slot 852 extending radially inward from the arcuate outer surfaces 838 , 839 of the first and second disks 830, 832 to the fiber channel boundary 855, and a fluid slot 854 radially inward with respect to the fiber slot 852. Hydrostatic bearing 820 also includes an internal component 836 located between the first disk 830 and the second disk 832, providing clearance between them. As shown in FIG. 10A, the width W _C of the fiber slot 452 is constant throughout the depth of the slot 452.

Further, similar to the hydrostatic bearings 420 of Figures 6A and 6B, the hydrostatic bearing 820 includes pressure relief regions 870 that include one or more porous material regions 876 located within the inner sides 842, 844 of the first and second discs 830, 832 in the radial the position of the fiber slot 852 in the fiber support channel 850 to allow flow 851 to exit the fiber slot 852 through the discs 830, 832 from the inner sides 842, 844 to the outer sides 843, 845. In addition, as shown in FIG. 10A, regions of porous material 876 are narrower in portions closer to the arcuate outer surfaces 838, 839 and wider in portions closer to fiber channel boundary 855, thereby allowing more flow 851 to exit fiber slot 852 through areas of porous material at locations closer to opening 860 of fiber slot 852 (e.g., when uncoated optical fiber 14 is higher in fiber slot 862) and allowing less flow 851 to exit fiber slot 852 through areas of porous material 876 at locations closer to the boundary 855 of the fiber channel in the fiber slot 852 (eg, when the uncoated optical fiber 14 is lower, ie, deeper in the fiber slot 852). Thus, the hydrodynamic flow will generate more lift when the bare optical fiber 14 is lower in the fiber slot 852 and therefore more work is required for the bare optical fiber 14 to move down and mechanically contact or enter the slot 854 for fluid.

As shown in FIG. 10A, the porous material regions 876 are narrower near the arcuate outer surfaces 838, 839 due to the sloped outer surfaces 843, 845 of the disks 830, 832, however, other configurations are acceptable to provide variable width of the porous material regions 876. For example, in one embodiment, with flat outer sides 843, 845, the porous material of the porous material regions 876 may extend from the inner sides 842, 844 to the outer sides 843, 845 near the fiber channel boundary 855, but does not extend to the outer sides 843, 845 at locations closer to the arcuate outer surfaces 838, 839 such that there is increased open space between the porous material regions 876 and the outer sides 843, 845 near the arcuate outer surfaces 838, 839. Alternatively, the porosity of the porous material regions 876 may vary with depth in the fiber slot 852. In one embodiment, the porosity of the porous material regions 876 decreases with increasing depth in the fiber slot 852 such that areas of higher porosity are adjacent to opening 860 and areas of lower porosity are adjacent to fiber channel boundary 855.

In FIG. 11A shows a partial side view of a hydrostatic bearing 920 capable of increasing the amount of power required to move bare optical fiber 14 from opening 960 to fiber channel boundary 955. The hydrostatic bearing 920 also includes an internal component 936 located between the first disk 930 and the second disk 932, providing clearance between them. In FIG. 11A, the hydrostatic bearing 920 includes pressure relief regions 970 that include one or more regions of porous material 976 that extend into the inner sides 942, 944 of the discs 930, 932, extending to the arcuate outer surfaces 938, 939 of the discs 930, 932, but not passing through the discs 930, 932 so that the flow 951 passing through the areas of porous material 976 exits through the arcuate outer surfaces 938, 939, and not through the outer sides of the discs 930, 932. Further, the depth of penetration of the areas of porous material 976 into the inner sides 942, 944 decreases at locations near fiber channel boundary 955 such that the path of hydrodynamic flow through regions of porous material 976 narrows as uncoated optical fiber 14 moves to lower (deeper) locations in fiber slot 952. This constriction reduces hydrodynamic flow through regions of porous material 976 as the uncoated optical fiber 14 approaches the channel boundaries 955 for the fiber 955, increasing the flow in the gaps, thereby increasing the lift applied to the uncoated optical fiber and thus requiring more operation so that the bare optical fiber 14 advances deeper into the fiber slot 952 and mechanically contacts or enters the fluid slot 954.

In FIG. 11B shows a partial side view of a hydrostatic bearing 1020 capable of increasing the energy required to move bare optical fiber 14 from opening 1060 to fiber channel boundary 1055. Hydrostatic bearing 1020 also includes an internal component 1036 located between the first disk 1030 and the second disk 1032, providing clearance between them. In FIG. 11B, the hydrostatic bearing 1020 includes pressure relief zones 1070 which comprise a series of porous material regions 1076a, 1076b, 1076c extending into the inner sides 1042, 1044 of the disks 1030, 1032 to the outer sides (not shown) of the disks 1030, 1032 so that the flow passing through areas of porous material 1076a, 1076b, 1076c, exits through the outer sides of the discs 1030, 1032.

Further, the porous material regions 1076a, 1076b, 1076c have different densities such that the porous material regions closer to the fiber channel boundary 1155 have a higher density (lower porosity) of the porous material, and the porous material regions closer to the arcuate outer surfaces 1038, 1039 of discs 1030, 1032 have a lower density (higher porosity) of the porous material. For example, the second porous material region 1076b (located between the first porous material region 1076a and the third porous material region 1076c) has a higher density than the first porous material region 1076a (which lies above the second porous material region 1076b) and a lower density than the third region of porous material 1076c (which is below the second region of porous material 1076b). Without being bound by any theory, it can be stated that increasing the density (reducing porosity) of the porous material regions 1076a, 1076b, 1076c near the fiber channel boundary 1055 reduces hydrodynamic flow 1051 through the porous material regions 1076a, 1076b, 1076c as uncoated optical fiber 14 approaches. towards the fiber channel boundary 1055, increasing the flow in the gaps and thereby increasing the lift applied to the bare optical fiber and hence increasing the amount of work required for the bare optical fiber 14 to advance deeper into the fiber slot 1052 and mechanically contact or included in the groove 1054 for the fluid.

Referring now to Figures 13A-14, further embodiments of the hydrostatic bearing are shown to reduce the likelihood of an uncoated optical fiber entering or making mechanical contact with a fluid slot. In particular, the hydrostatic bearings of Figures 13A-14 comprise one or more anti-shift elements located at or near the fiber channel boundary that define a position in the fiber support channel where there is a sudden increase in lift applied to the bare optical fiber. The sudden increase in lift prevents or limits mechanical contact and/or entry of the bare optical fiber into the fluid slot of the fiber support channel.

Figures 13A and 13B show a hydrostatic bearing 1120 including one or more anti-shift elements 1180. In particular, FIG. 13A shows a partial side view of a hydrostatic bearing 1120, and FIG. 13B is a partial front view of the hydrostatic bearing 1120 showing the outer side 1143 of the first disc 1130. Similar to the hydrostatic bearing 120 of Figures 3A and 3B, the hydrostatic bearing 1120 includes a fiber support channel 1150 with a fiber slot 1152 extending radially inward from the hole 1160 on the arcuate outer surfaces 1138, 1139 of the first and second disks 1130, 1132 to the fiber channel boundaries 1155, and with a fluid slot 1154 located radially inward from the fiber slot 1152. The hydrostatic bearing 1120 also includes an inner component 1136 located between the first disc 1130 and the second disc 1132, providing clearance between the inner side 1142 of the first disc 1130 and the inner side 1144 of the second disc 1132. Width W _C of the fiber slot 1152 between the inner sides 1142, 1144 varies along the depth of the slot 1152, decreasing as the uncoated optical fiber 14 approaches the fiber channel boundaries 1155.

In addition, as shown in FIGS. 13A and 13B, the one or more anti-bias elements 1180 comprise a plurality of boundary holes 1182 located on or near a fiber support channel boundary 1155 (e.g., located such that a fiber channel boundary 1155 intersects each boundary hole 1182, or such that the boundary holes 1182 are spaced from the fiber channel boundary in either the fluid slot 1154 or the fiber slot 1152 (e.g., in shallower areas of the fluid slot 1154 or in deeper slot areas 1152 for fiber). at a location up to 50 fiber diameters above or below the fiber channel boundary 1155, or locations e, up to 25 fiber diameters above or below the fiber channel boundary 1155, or at a location up to 10 fiber diameters above or below the fiber channel boundary 1155, or at a location in the range of 1-100 fiber diameters above or below the boundary 1155 fiber channels, or in the range of 1-50 fiber diameters above or below the fiber channel boundary 1155, or in the range of 1-25 fiber diameters above or below the fiber channel boundary 1155, or in the range of 1-10 fiber diameters above or below channel boundaries 1155 for the fiber. During manufacture, the boundary holes 1182 provide a path for the fluid 1151, allowing it to leave the fiber support channel 1150 before reaching the fiber slot 1152 and thus hydrodynamic flow within the fluid slot 1154 (more specifically, hydrodynamic flow below the boundary holes 1182 ) may be substantially higher than the hydrodynamic flow within the fiber slot 1152 (more specifically, the hydrodynamic flow above the boundary holes 1182). Thus, when the bare optical fiber 14 is displaced deep into the fiber support channel 1150 so that it reaches the boundary holes 1182, the bare optical fiber 14 is in contact with the flow 1151, flowing at an increased speed, which applies increased lift to the bare optical fiber 14 and, therefore , more work is needed for the uncoated optical fiber 14 to pass the boundary holes 1182 deeper into the fiber support channel 1150, or to make mechanical contact or enter the fluid slot 1154. Although an embodiment of a hydrostatic bearing 1120 comprising boundary holes 1182 is depicted in Figures 13A and 13B as comprising a tapered fiber slot 1152, it should be understood that boundary holes 1182 may be provided in any of the hydrostatic bearing embodiments described herein.

As an illustration, consider an example of a hydrostatic bearing 1120 having a radius of 3 inches, boundary holes 1182 each 0.006 inches in diameter and 0.04 inches deep (for example, passing through disks 1130, 1132 about 0.04 inches thick, azimuthally spaced 2 degrees apart, the lift applied to the bare optical fiber 14 in the fiber slot 1152 just above the boundary holes 1182 is approximately 200 grams. boundary holes 1182 and will remain at 400 grams at any depth in the fluid slot 1154 (because the fluid slot 1154 has a constant width). work to shift the uncoated optical fiber 14 to positions below the boundary from 1182. The displacement of the bare optical fiber 14 to mechanical contact or entry into the fluid slot 1154 is prevented by the boundary holes 1182.

Let us now turn to FIG. 14, which shows a partial plan view of a hydrostatic bearing 1220 including one or more fiber channel boundary elements 1280. Similar to the hydrostatic bearing 120 of Figures 3A and 3B, the hydrostatic bearing 1220 has a fiber support channel 1240 with a fiber slot 1252 extending radially inward from the opening 1260 at the arcuate outer surfaces 1238, 1239 of the first and second discs 1230, 1232 to the fiber channel boundary 1255. fibers, and a fluid slot 1254 located radially within (eg, below) the fiber slot 1252. The _hydrostatic bearing 1220 also includes an internal component 1236 located between the first disk 1230 and the second disk 1232, providing clearance between the inner side 1242 of the first disk 1230 and the inner side 1244 of the second disk 1232. 1252, decreasing as the uncoated optical fiber 14 approaches the fiber channel boundary 1255. In various embodiments, the depth of the fiber slot 1252 is greater than 0.25 inches, or greater than 0.40 inches, or greater than 0.55 inches, or greater than 0.70 inches, or greater than 0.85 inches, or lies between 0, 25 inches to 1.25 inches, or in the range of 0.35 inches to 1.05 inches, or in the range of 0.45 inches to 0.90 inches, or in the range of 0.55 inches to 0.85 inches, or in the range of 0.60 inch to 0.80 inch, or about 0.65 inch, or about 0.75 inch.

Further, as shown in FIG. 14, the one or more anti-displacement members 1280 comprise a plurality of compression zones 1284 located at or near the boundary 1255 of the fiber support channel 1250. The compressive zones 1284 are portions of the inner sides 1242, 1244 of the discs 1230, 1232 at the fiber channel boundary 1255 that converge cone at a greater angle to the Z-axis (e.g., an upward/downward radial axis of the uncoated relative to the optical fiber 14, which corresponds to the depth or direction of displacement of the bare optical fiber 14 in the fiber slot 1252) than the inner side portions 1242, 1244 defining the fiber slot 1252. In other words, the amount of inclination of the portions of the inner sides 1242, 1244 defining the fiber slot 1252 is less than the amount of inclination of the compression zones 1284, which results in a narrowing of the channel 1250 for supporting the fiber and a decrease in the width of the zone available for hydrodynamic flow 1251.

During manufacture, as the compression zones 1284 constrict the fiber support channel 1250, the lift force of the hydrodynamic flow 1251 for supporting (lifting) the bare optical fiber 14 increases when the displacement depth of the bare optical fiber 14 in the fiber support channel 1250 reaches the compression zones. 1284. For example, if the angle of the portions of the inner sides 1242, 1244 that define the fiber slot 1252 to the Z axis is 0.6 degrees, and the angle of the constricting zones 1284 to the Z axis is 2 degrees, the gap between the uncoated optical fiber 14 and the inner walls 1242 , 1244 is halved when the bare optical fiber 14 reaches the compression zones 1284 and the lifting force on the bare optical fiber 14 is doubled. Thus, it should be understood that the introduction of compression zones 1284 means that more work is required for the uncoated optical fiber 14 to mechanically contact or enter the fluid slot 1254.

In alternative embodiments of the fiber channel configurations described herein, it is understood that the fiber slot preferably includes parallel vertical inner walls at the entrance to the fiber slot opening. Although not explicitly shown in the drawings, any of the fiber slot embodiments described herein preferably comprises a pair of parallel inner walls in an outer radial position. In some embodiments, the fiber slot comprises a combination of one or more conical inner walls and one or more vertical inner walls. For example, FIG. 15 shows a fiber slot with an oblique configuration of the type shown in FIG. 3A with a pair of parallel vertical inner walls inserted at an outer radial position near the fiber entry point into the fiber slot. The fiber support channel 1360 with opening 1360 includes a fluid slot 1354 and a fiber slot 1352. The fiber slot 1352 has an inner wall 1344 tapering at an angle α and a vertical inner wall 1346, each having an opposite inner wall as shown in FIG. 15. The fiber 14 will be in a fiber slot portion with parallel vertical inner walls under very low tension and the hydrodynamic flow force opposing downward (radially inward) movement of the fiber will not change with depth in the fiber slot between the parallel vertical inner walls. However, to move the fiber in a downward direction (radially inward) in the portion of the fiber slot having vertical inner walls, work would have to be done. A representative depth of the parallel section defined by the vertical inner wall 1346 and its opposite equivalent is 0.55 inches. A representative depth of the tapered section defined by inner wall 1344 and its opposite equivalent is 0.20 inches. A representative depth from opening 1360 to fiber support channel boundary 1355 is 0.75 inches.

Further, other embodiments of hydrostatic bearings are conceivable to prevent downward displacement of an uncoated optical fiber, or to prevent or limit mechanical contact of an uncoated optical fiber and/or its entry into the fluid slot of the fiber support channel. For example, increasing the flow rate through a hydrostatic bearing (for example, by increasing the hydrodynamic flow introduced into a fluid slot or fiber support channel) will increase the equilibrium height of an uncoated optical fiber for any downward force applied, thereby increasing the amount of work required to moving the uncoated optical fiber downward in the channel to support the fiber or to mechanically contact or enter the fluid slot. In addition, increasing the depth of the fiber slot in the fiber support channel will reduce the chance of mechanical contact of the uncoated optical fiber and/or its entry into the fluid slot of the fiber support channel.

Thus, the hydrostatic bearings described herein are capable of performing many functions, including providing a non-vertical path for producing optical fibers. However, hydrostatic bearings can be used in any combination with the optical fiber transport methods discussed earlier in this document. In addition, it should be understood that the embodiments of hydrostatic bearings discussed and illustrated herein may be used at any stage in the production of optical fiber. Due to the ability to provide a non-vertical path to the coater, hydrostatic bearings and optical fiber production systems containing these hydrostatic bearings have the freedom of choice of design solutions, since the components can be easily manipulated and interchanged in optical fiber production systems, while offering systems, which take up less space compared to hood towers. In addition, by using the hydrostatic bearing configurations described herein, an uncoated optical fiber can be held in a fiber slot in a fiber support channel that is sized and configured to surround the uncoated optical fiber, and mechanical contact of the uncoated optical fiber can be prevented. fiber and/or getting into the fluid slot of the channel to support the fiber. Accordingly, the systems for producing optical fiber, including hydrostatic bearings, and the methods for producing optical fibers described herein provide many advantages over conventional systems and methods.

As used herein, ranges may be expressed as from "about" one specific value, and/or to "about" another specific value. When such a range is explicitly specified, another embodiment includes a range from one particular value and/or to another particular value. Likewise, when values are expressed as approximate using the preceding word "about", it should be understood that this particular value constitutes another embodiment. In addition, it should be understood that the endpoints of each of the ranges are significant both with respect to the other endpoint and independently of the other endpoint.

Direction terms used in this document, such as up, down, right, left, front, back, top, bottom, are used only when referring to shapes as they are drawn and do not imply absolute orientation.

Unless explicitly stated otherwise, it is by no means intended that any method set forth herein should be construed as requiring its steps to be performed in a particular order, or that any particular device-specific orientations are required. Accordingly, if a claim relating to a method does not specify the order in which its steps must follow, or if any claim relating to an apparatus does not explicitly state the order or orientation relative to the individual components, or if the claim or description otherwise it is not stated that the steps are to be limited to a particular order, or if a particular order or orientation with respect to the components of the device is not indicated, it is in no way intended to imply any order or orientation. This is true for any, perhaps not explicitly stated, basis for interpretation, including questions of logic regarding the organization of stages, sequence of operations, order of components, or orientation of components; the generally accepted meaning inferred from grammatical constructions or punctuation, and the number or type of embodiments presented in the description.

As used here, the singular forms include plural references unless the context clearly dictates otherwise. Thus, for example, the use of one component implies variants with two or more such components, unless the context clearly indicates otherwise.

Those skilled in the art will appreciate that various modifications and changes may be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Thus, the description is intended to cover modifications and variations of the various embodiments described herein, provided that such modifications and variations are within the scope of the appended claims and their equivalents.

Claims (32)

1. A hydrostatic bearing for use in the manufacture of optical fiber, the bearing comprising: - an optical fiber path designed to pull the optical fiber along it through the hydrostatic bearing by means of tension; moreover, the hydrostatic bearing includes a channel for supporting the fiber, located between the first disk and the second disk; wherein the first disk has a first inner side, a second inner side adjacent to the first inner side, and a first outer surface; and the second disc has a third inner side, a fourth inner side adjacent to the third inner side, and a second outer surface; wherein the first inner side, the second inner side, the third inner side, and the fourth inner side face the fiber support channel; wherein the channel for supporting the fiber has an opening; the fiber support channel extends from the hole in the depth direction between the first disc and the second disc; the first inner side and the third inner side have a first amount of inclination with respect to an axis extending in the depth direction; the second inner side and the fourth inner side have a second inclination to an axis extending in the depth direction, the first inclination being different from the second inclination; and the hole is designed to enter through the optical fiber in the channel to support the fiber; and a fluid path for guiding fluid with a force acting on the optical fiber as it is pulled through the hydrostatic bearing along the path of the optical fiber in the fiber support channel; wherein the force generated by the fluid is opposite to the tension and is capable of stabilizing the optical fiber in the channel to support the fiber in a position where the optical fiber is not in contact with the first disk or the second disk. 2. The hydrostatic bearing of claim 1, wherein the first inner side, the second inner side, the third inner side, and the fourth inner side are linear segments. 3. The hydrostatic bearing of claim 1, wherein the first inner side is adjacent to the first outer surface and the third inner side is adjacent to the second outer surface, and wherein the first slope is less than the second slope. 4. The hydrostatic bearing of claim 1, wherein the first amount of inclination is defined by a first angle to an axis extending in the depth direction, the first angle being greater than 0°. 5. Hydrostatic bearing according to claim 4, wherein the first angle is greater than 0.1°. 6. Hydrostatic bearing according to claim 4, wherein the first angle is greater than 0.3°. 7. Hydrostatic bearing according to claim. 4, in which the first angle lies in the range of 0.1-9°. 8. The hydrostatic bearing of claim 4, wherein the second amount of inclination is defined by a second angle to an axis extending in the depth direction, the second angle being greater than 0°. 9. Hydrostatic bearing according to claim 8, wherein the first angle is greater than 0.2° and the second angle is greater than 0.1°. 10. Hydrostatic bearing according to claim 8, wherein the first angle is in the range of 0.1-9° and the second angle is in the range of 0.3-7°. 11. A hydrostatic bearing according to claim 8, wherein the first angle is greater than the second angle by at least 0.3°. 12. Hydrostatic bearing for use in the manufacture of optical fiber, and the bearing contains: - an optical fiber path designed to pull the optical fiber along it through the hydrostatic bearing by means of tension; moreover, the hydrostatic bearing includes a channel for supporting the fiber, located between the first disk and the second disk; wherein the first disc has a first inner side and a first outer side, the second disc has a second inner side and a second outer side; wherein the first inner side and the second inner side face the fiber support channel; the channel for supporting the fiber has an opening; the fiber support channel extends from the hole in the depth direction between the first disc and the second disc; and the hole is designed to enter through the optical fiber in the channel to support the fiber; and a fluid path for guiding fluid with a force acting on the optical fiber as it is pulled through the hydrostatic bearing along the path of the optical fiber in the fiber support channel; moreover, the force of the fluid is opposite to the tension and is able to stabilize the optical fiber in the channel to support the fiber in a position in which the optical fiber is not in contact with the first disk or the second disk; moreover, the force generated by the fluid, given the profile of the force describing the dependence of the force of the fluid from the depth of the optical fiber in the channel to support the fiber; wherein the fiber support channel is configured such that the force profile is convex. 13. The hydrostatic bearing according to claim 12, in which the first inner side contains a first set of holes, and the second inner side contains a second set of holes, each hole from the first set extends from the first inner side to the first outer side, and each hole from the second set extends from the second inner side to the second outer side. 14. The hydrostatic bearing according to claim 13, in which each hole from the first set extends from the first inner side through the first disc to the first outer side, and each hole from the second set extends from the second inner side through the second disc to the second outer side. 15. The hydrostatic bearing according to claim 13, in which each hole from the first set has a first non-constant width in the first inner side, and each hole from the second set has a second non-constant width in the second inner side, and the first non-constant width and the second non-constant width decrease in depth direction. 16. The hydrostatic bearing according to claim 13, in which each hole from the first set has a first direction of propagation from the first inner side to the first outer side, and each hole from the second set has a second direction of propagation from the second inner side to the second outer side, the first the propagation direction is perpendicular to the depth direction, and the second propagation direction is perpendicular to the depth direction. 17. The hydrostatic bearing according to claim 16, in which each hole from the first set has a first variable length in the first direction of propagation, and each hole from the second set has a second variable length in the second direction of propagation, and the first variable length and the second variable length decrease in depth direction. 18. The hydrostatic bearing of claim 17, wherein the first variable length and the second variable length vary non-linearly in a depth direction. 19. Hydrostatic bearing according to claim 12, in which the first inner side contains the first porous material, and the second inner side contains the second porous material, the first porous material extends from the first inner side to the first outer side, and the second porous material extends from the second inner side to the second outer side. 20. The hydrostatic bearing of claim 19, wherein the first porous material extends from the first inner side through the first disc to the first outer side, and the second porous material extends from the second inner side through the second disc to the second outer side. 21. The hydrostatic bearing according to claim 19, in which the first porous material has a first direction of propagation from the first inner side to the first outer side, and the second porous material has a second direction of propagation from the second inner side to the second outer side, and the first direction of propagation is perpendicular to the direction depth and a second propagation direction perpendicular to the depth direction. 22. A method for producing an optical fiber, including: - the direction of the uncoated optical fiber on the first path to the hydrostatic bearing, and the hydrostatic bearing contains the first disk, the second disk and the channel for supporting the fiber, located between the first disk and the second disk; the first disc has a first inner side, a second inner side adjacent to the first inner side, and a first outer surface adjacent to the first inner side; and the second disc has a third inner side, a fourth inner side adjacent to the third inner side, and a second outer surface adjacent to the third inner side; wherein the first inner side, the second inner side, the third inner side, and the fourth inner side face the fiber support channel; the channel for supporting the fiber has an opening; the fiber support channel extends from the hole in the depth direction; the first inner side and the third inner side have a first amount of inclination with respect to an axis extending in the depth direction; the second inner side and the fourth inner side have a second inclination to an axis extending in the depth direction, the first inclination being different from the second inclination; wherein the optical fiber enters the fiber support channel through the opening; and flow of fluid through the fiber support channel to the opening of the fiber support channel, the fluid contacting the bare optical fiber and providing lift to the bare fiber, the lift being given by a force profile describing the relationship of the lift in the depth direction of the bare fiber optical fiber in the channel to support the fiber. 23. The method of claim 22, wherein the direction includes drawing an uncoated optical fiber from an optical fiber drawing preform. 24. The method of claim 22, wherein the direction includes passing an uncoated optical fiber at a speed greater than 50 m/s along the first path. 25. The method of claim 22, wherein the guiding includes applying tension to the bare optical fiber. 26. The method of claim 22, wherein the hydrostatic bearing redirects the bare optical fiber from the first path to the second path.

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