WO2025019627A1

WO2025019627A1 - Apparatus for winding filaments or strands

Info

Publication number: WO2025019627A1
Application number: PCT/US2024/038463
Authority: WO
Inventors: Emmanuel Vaquant; Pierre-Jacques Font
Original assignee: Owens Corning Intellectual Capital LLC
Current assignee: Owens Corning Intellectual Capital LLC
Priority date: 2023-07-19
Filing date: 2024-07-18
Publication date: 2025-01-23
Anticipated expiration: 2026-01-19

Abstract

A strand guide (302) for comingling fiber strands (310). The strand guide includes a first comingling member or strand engaging member (304) extending from the strand guide and a second comingling member or strand engaging member (306) extending from the strand guide wherein the first comingling member includes a first pair of teeth (314) defining a first groove (316) between the first pair of teeth, wherein the second comingling member includes a second pair of teeth (344) defining a second groove (346) between the second pair of teeth, and wherein the first and second pairs of teeth are at least partially offset from one another along a length of the strand guide.

Description

APPARATUS FOR WINDING FILAMENTS OR STRANDS

CROSS REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims priority to and the benefit of European Patent Application No. 23186557.7, filed July 19, 2023, the entire content of which is incorporated by reference herein.

FIELD

[0002] The present invention relates to winding fiber strands comprising a plurality of fibers onto a rotating support to form a bobbin, cake, or the like.

BACKGROUND

[0003] It is generally known in the art to wind elongate strands of fibers or filaments onto a rotating support to form cakes (sometimes also referred to in the art as bobbins or packages or spools or rolls) of the wound material. In the field of glass fiber materials, it is generally known to draw a plurality of glass fibers from a molten glass source flowing through a bushing to obtain a relatively large number (e.g., a thousand) of glass fibers or filaments. A predetermined number of the glass fibers are grouped to obtain a respective glass fiber strand (sometimes referred to in the art as a split). One or more glass fiber strands are then wound on a rotatable spindle having an axis of rotation to form a cake or bobbin.

[0004] FIG. 1 is a schematic illustration of a glass fiber strand winding system 100. A bushing 102, which may be part of a bushing assembly, is a metallic box-shaped structure through which molten glass (from a conventional source of molten glass, not shown) flows to form a plurality (as many as several thousands) of individual glass filaments 104 that can be drawn (i.e., pulled) through the rest of the process. A conventional sizing composition may be optionally deposited on the glass filaments 104 by a conventional sizing device 106. In an example of a conventional sizing device, the glass filaments 104 may be passed through or adjacent to the sizing device 106 to deposit a predetermined sizing composition, for example, by passing the glass filaments 104 against a surface (such as a roller) wetted with the sizing composition. The sizing composition may be useful, for example, for protecting the glass filaments from breakage or to enhance bonding with a reinforcing matrix in a composite material.

[0005] Next, the glass filaments 104 are separated by a separating device 108 into several groups of filaments to obtain discrete glass fiber strands 110, each glass fiber strand 110 having a plurality of filaments, for example, up to about two hundred (200) filaments each. The conventional separating device 108 has, for example, a plurality of spaced apart teeth like a comb. Accordingly, each group of filaments is separated from other groups by the teeth of the separating device 108 to define the corresponding plurality of generally parallel glass fiber strands 110. The one or more glass fiber strands 110 are thereafter wound on a spindle or other elongate rotating support 112 to obtain a wound cake 114 of glass fiber strands. It is known in the art to use a mechanical traversing apparatus 116 to laterally displace the one or more glass fiber strands along an axial length of the spindle 112 to distribute the glass fiber strands during winding, so that the cake 114 is wound consistently and, particularly, can be unwound reliably when desired. The mechanical traversing apparatus in FIG. 1 is indicated schematically at 116, and generally functions by rotating along an axis of rotation X to displace the glass fiber strands 110 in a reciprocating fashion back and forth along an axial portion of the spindle 112, while the glass fiber strands 110 are being wound onto the spindle 112, to ensure the cake 114 has a uniform/consi stent arrangement of the glass fiber strands 110 thereon. The rotatably mounted spindle 112 is driven to rotate about an axis of rotation X’ by conventional mechanical driving means, such as a motor (not shown here).

[0006] Some conventional examples of traversing apparatus 116 include devices driven to rotate about an axis, having various rectilinear and curvilinear bars, blades, surfaces, and the like that are inclined in predetermined orientations relative to the axis of rotation of the device. The conventional traversing apparatuses are placed to be in contact with the one or more glass fiber strands 110, downstream of the separating device 108 and upstream of the rotating spindle 112. The arrangement of the bars on the traversing apparatus 116, which selectively contact the glass fiber strands 110 as a function of the rotation of the traversing apparatus 116, generally displaces the glass fiber strands in a reciprocating fashion back and forth along an axis of rotation of the traversing apparatus 116 to deposit the glass fiber strands 110 along an axial length of the cake 114 being wound (i.e., from A to A’).

[0007] Examples of conventional traversing apparatuses are disclosed in, for example, U.S. Pat. No. 2,989,258; U.S. Pat. No. 3,292,872; U.S. Pat. No. 3,356,304; U.S. Pat. No. 3,399,841; U.S. Pat. No. 3,784,121; U.S. Pat. No. 3,819,344; U.S. Pat. No. 3,861,608; U.S. Pat. No. 3,946,957; U.S. Pat. No. 4,239,162; U.S. Pat. No. 5,669,564; and U.S. Pat. Pub. No. U.S. 2012/0167634.

[0008] As seen in FIG. 2, once several cakes 114 are wound, the plurality of respective glass fiber strands 110 wound about each cake 114 as illustrated in FIG. 1 is thereafter pulled from a plurality of cakes 114, as represented in FIG. 2. The several pluralities of glass fiber strands 110 taken from the plurality of cakes 114 are thereafter wound together to form a “roving assembly” 120 (sometimes referred to as a “multi-end” (in reference to the amassed grouping of discrete glass fiber strands) package or “doff’).

[0009] For example, in FIG. 2, each of the three (3) cakes 114 may each comprise twelve (12) wound glass fiber strands 110. To manufacture the roving assembly 120, each group of twelve (12) glass fiber strands from each cake 114 are taken together to form the roving assembly 120. Thus, the roving assembly 120 should provide thirty-six (36) glass fiber strands when it is unwound in subsequent use. A roving assembly 120 is typically used as a source of continuous glass fiber, for example, for subsequent production of chopped glass fiber for use as a composite material reinforcement (i.e., the glass fibers are chopped and incorporated into a resinous matrix to form a reinforced the composite material). In such use, the roving assembly 120 is unwound at relatively high speed to provide the glass fiber for subsequent manufacturing processes.

[0010] Conventional processes for the manufacture of roving assemblies, however, are known to have defects. One such defect is a variation in the number of strands wound in the final roving assembly. This can in turn cause variations in the amount of glass material that is in each roving assembly, compared to an expected amount. In some cases, this problem can be traced back to manufacture of the cakes 114. If the respective glass fiber strands 110 are not kept at a desired separation while the cake 114 is wound, the glass fiber strands 110 can stick together, referred to as “matchsticking.” Matchsticking can occur over a non-trivial length, particularly after a sizing deposited by the sizing device 106 is cured. This problem can occur very quickly while the cakes 114 are wound, given the rate of winding (sometimes as much as 25 meters of strand material per second). In effect, there may be fewer glass fiber strands 110 than expected, because the strands adhere to one another.

[0011] Another conventionally recognized defect is the generation of loops in the strands in the roving assembly after the roving assembly 120 is wound. Most generally, this is caused by strands being unevenly (in a lengthwise sense) wound onto a respective cake 114 during manufacture. For example, in a cake having tapered or conical ends when seen from the side (similar to the truncated ellipsoidal form of cake 114 seen in FIGS. 1 and 2), the length of a given strand that is wound on the cake will be lower as a function of the proximity of that strand to an axial end of the cake. As the diameter of the cake at its axial end is smaller than at its middle, the length of strands wound at the end of the cake is shorter than the length of strands wound towards the axial center of the cake. [0012] For example, in FIG. 1, the linear extent of leftmost glass fiber strand 110' that is wound onto spindle 112 will vary depending on how far strand 110' is from the left end A of cake 114, as the collective group of strands is reciprocally traversed by traversing apparatus 116. That is, a shorter length of strand 110' will be wound onto spindle 112 when the strand 110' is closest to end A of cake 114 because the diameter of the cake at that point is the smallest. Greater and greater lengths of strand 110' are wound onto spindle 112 as the group of strands is traversed to the right by traversing apparatus 116 because the diameter of the cake 114 (corresponding to the instant position of strand 110') progressively increases toward the center thereof. Obviously, this variance is reversed when the group of strands is subsequently traversed towards the left from the right end A’ of the cake 114.

[0013] Furthermore, when the group of glass fiber strands is considered collectively in this context, it is evident that at a given moment longer and longer lengths of the respective strands to the right of strand 110', respectively, are wound on the spindle 112. Thus, each glass fiber strand is wound onto the spindle at different rates and when the cake is unwound, the respective strands pulled from a given cake will have different lengths. Theoretically, this effect cancels itself out in a “roundtrip” of the group of fiber strands (i.e., when the group of fiber strands completes a full trip in one sense and a return trip, thanks to traversing apparatus 116). However, that depends on keeping the strands in the same order as the glass fiber strands 110 are traversed back and forth. As a practical matter, this happens rarely, at least partly due to problems with conventional traversing apparatuses.

[0014] Accordingly, when a collection of glass fiber strands is unwound from the cake 114, some of the glass fiber strands may be longer than others. This excess length is sometimes referred to as “catenary” and manifests itself as loose or slack portions of strand that tend to twist and loop.

[0015] As shown in FIG. 3, the problem with “catenary” and random “matchsticking” can be interrelated. For example, a longer strand 130 can stick to a shorter strand 132 at multiple locations along the length of the short strand 132. In FIG. 3, the longer strand 130 is illustrated as sticking to the shorter strand 132 at a first location 134 and at a second location 136. Due to the excess length of the longer strand 130, the longer strand 130 forms a loop or catenary 138 between the first location 134 and the second location 136. Since the distance between the first location 134 and the second location 136 can be relatively larger, the loop or catenary can be large and result in defects when the strands 130, 132 are unwound.

[0016] It is therefore of interest to improve systems for winding glass fiber strands into cakes, taking into account the above-mentioned problems. SUMMARY

[0017] Various aspects of the present inventive concepts are directed to a system, apparatus, and method of winding fiber strands comprising a plurality of fibers onto a rotating support to form a bobbin, cake, or the like. As used herein, a strand engaging member may engage fiber strands and a comingling member may engage fiber strands and may comingle filaments of fiber strands. Accordingly, a strand engaging member may comprise a comingling member, and a comingling member may constitute a strand engaging member.

[0018] In some examples, a strand guide for engaging a plurality of fiber strands prior to the plurality of the fiber strands being wound onto a support includes a first strand engaging member. The first strand engaging member is movable between a first position in which the first strand engaging member is in contact the plurality of fiber strands and a second position in which the first strand engaging member does not contact the plurality of fiber strands. When in contact with the plurality of fiber strands, the first strand engaging member causes at least two of the plurality of fiber strands to contact each other.

[0019] In some examples, a system for winding a plurality of fiber strands onto an elongate spindle includes a supply of filaments, a separating device, a rotatably mounted spindle, a traversing apparatus, and a strand guide. The separating device is configured to separate the filaments into several groups of filaments to form the plurality of fiber strands. The rotatably mounted spindle is driven to rotate about first axis of rotation. The traversing apparatus is constructed and arranged to displace the plurality of fiber strands in a reciprocating manner along an axial length of the spindle while the fiber strands are being wound upon the spindle. The strand guide is positioned between the separating device and the traversing apparatus for engaging the plurality of fiber strands from the separating device. The strand guide includes a first strand engaging member that is movable between a first position in which the first strand engaging member is in contact the plurality of fiber strands and a second position in which the first strand engaging member does not contact the plurality of fiber strands. When in contact with the plurality of fiber strands, the first strand engaging member causes at least two of the plurality of fiber strands to contact each other.

[0020] According to an aspect of the invention, there is provided a strand guide for comingling a plurality of filaments of a plurality of fiber strands includes a first comingling member extending from the strand guide.

[0021] Optionally, the first comingling member includes a first pair of teeth defining a first groove between the first pair of teeth. [0022] Optionally, the strand guide further includes a second comingling member extending from the strand guide in a direction substantially opposite the first comingling member.

[0023] Optionally, the second comingling member includes a second pair of teeth defining a second groove between the second pair of teeth.

[0024] Optionally, the first and second pairs of teeth are at least partially offset from one another along a length of the strand guide.

[0025] Optionally, the first and second pairs of teeth are offset from one another such that the first groove is substantially aligned with a tooth of the second pair of teeth.

[0026] Optionally, the first and second pairs of teeth are offset from one another such that the second groove is substantially aligned with a tooth of the first pair of teeth.

[0027] Optionally, the strand guide is movable between a first position proximal to the fiber strands and a second position distal to the fiber strands.

[0028] Optionally, at least one of the first and second comingling members is configured to comingle the filaments of the fiber strands while the strand guide is in the first position.

[0029] Optionally, the strand guide is in the first position for a first period of time and in the second position for a second period of time.

[0030] Optionally, one instance of the first period and one instance of the second period constitute a cycle.

[0031] Optionally, the second period is greater than the first period.

[0032] Optionally, a ratio of the second period to the first period is in the range of about 2: 1 to about 20: 1.

[0033] Optionally, the ratio is in the range of about 4: 1 to about 10: 1.

[0034] Optionally, the ratio is in the range of about 6: 1 to about 7: 1.

[0035] Optionally, the fiber strands comprise a first linear portion having a first split efficiency of up to 100%.

[0036] Optionally, the strand guide causes a second linear portion of the fiber strands to have a second split efficiency in the range of about 50% to about 80% while the strand guide is in the first position.

[0037] Optionally, a length-weighted average split efficiency of the first linear portion and the second linear portion is at least about 80%.

[0038] Optionally, the length-weighted average split efficiency is at least about 90%.

[0039] Optionally, the length-weighted average split efficiency is at least about 95%.

[0040] Optionally, the strand guide is rotatable to a first rotated position wherein the first comingling member is proximal to and/or substantially perpendicular to the fiber strands. [0041] Optionally, the first groove is configured to bring a first fiber strand and a second fiber strand into contact with each other while the strand guide is in the first rotated position. Optionally, the first groove is further configured to comingle at least some of the filaments of the first fiber strand with at least some of the filaments of the second fiber strand while the strand guide is in the first rotated position.

[0042] Optionally, the strand guide is rotatable to a second rotated position wherein the second comingling member is proximal to and/or substantially perpendicular to the fiber strands.

[0043] Optionally, the second groove is configured to bring the second fiber strand and a third fiber strand into contact with each other while the strand guide is in the second rotated position. Optionally, the second groove is further configured to comingle at least some of the second filaments of the second fiber strand with at least some of third filaments of the third fiber strand while the strand guide is in the second rotated position.

[0044] Optionally, the strand guide is rotatable to a third rotated position wherein the first and second comingling members are substantially parallel to the fiber strands.

[0045] According to an aspect of the invention, there is provided a system for winding a plurality of strands comprising a fibrous material onto a spindle to form a cake. The system comprises a plurality of filaments; a separating device configured to separate the filaments into groups, each of the groups corresponding to one of the strands; a spindle driven to rotate about a spindle axis of rotation, so that the strands are wound thereon; a traversing apparatus for displacing the strands in a reciprocating manner along an axial length of the spindle while the strands are wound on the spindle; and a strand guide positioned between the separating device and the traversing apparatus for selectively engaging the strands. The strand guide may be any of the strand guides described herein.

[0046] Optionally, the strand guide is in the first position for a first period of time and in the second position for a second period of time, and one instance of the first period and one instance of the second period constitute a cycle. The cycle may correspond to the traversing apparatus traveling about twice an axial length of the cake.

[0047] Optionally, the traversing apparatus is rotatable about a traversing apparatus axis of rotation.

[0048] Optionally, the traversing apparatus comprises a first bar configured to engage and move the strands in a first direction relative to the traversing apparatus axis of rotation.

[0049] Optionally, the traversing apparatus comprises a second bar configured to engage and move the strands in a second direction relative to the traversing apparatus axis of rotation. The second direction may be opposite the first direction. [0050] Optionally, the first bar is curved radially inward toward the traversing apparatus axis of rotation such that a central portion of the first bar is more proximal to the traversing apparatus axis of rotation than an end portion of the first bar.

[0051] Optionally, the second bar is curved radially inward toward the traversing apparatus axis of rotation such that a central portion of the second bar is more proximal to the traversing apparatus axis of rotation than an end portion of the second bar.

[0052] Optionally, the traversing apparatus comprises a third bar disposed between the first bar and the second bar. The third bar may be straight.

[0053] Optionally, at least one of the first bar and the second bar has a curvature in the range of about 15 mm to about 50 mm. The curvature may be in the range of about 25 mm to about 45 mm. The curvature may be in the range of about 30 mm to about 42 mm. The curvature may be in the range of about 25 mm to about 40 mm.

[0054] Optionally, the measure of the curvature of the at least one of the first bar and the second bar is a distance (D) that a midpoint (M) of the curvature is from a straight-line (SL) connecting a first end and a second end of the at least one of the first bar and the second bar.

[0055] Optionally, the curvature of the at least one of the first bar and the second bar is substantially symmetrical about a central axis that bisects the curvature.

[0056] In some examples, a method of winding the plurality of fiber strands onto a spindle includes providing a plurality of filaments; separating the plurality of filaments into groups, each group of the filaments forming one of the fiber strands; rotating the spindle to wind the fiber strands onto the spindle; selectively engaging the fiber strands with a strand guide prior to winding fiber strands on the spindle to cause a first fiber strand and a second fiber strand of the fiber strands to contact each other; and displacing the fiber strands in a reciprocating fashion along an axial portion of the spindle while the fiber strands are being wound onto the spindle. [0057] Optionally, the method may further include causing the first fiber strand and the second fiber strand to contact each other further comprises causing at least some of first filaments of the first fiber strand to comingle with at least some of second filaments of the second fiber strand.

[0058] Optionally, the method may further include selectively engaging the fiber strands further comprises rotating the strand guide to a first rotated position to cause the first fiber strand and the second fiber strand to contact each other.

[0059] Optionally, the method may further include selectively engaging the fiber strands further comprises rotating the strand guide to a second rotated position to cause the second fiber strand and a third fiber strand of the fiber strands to contact each other. [0060] Optionally, the method may further include selectively engaging the fiber strands further comprises rotating the strand guide to a third rotated position to prevent any of the fiber strands from contacting each other.

[0061] Optionally, the method may further include selectively engaging the fiber strands further comprises moving the strand guide between a first position proximal to the fiber strands in which the strand guide is engageable with the fiber strands and a second position distal to the fiber strands in which the strand guide is not engageable with the fiber strands.

[0062] The aforementioned method may be carried out using the aforementioned strand guide aspect of the invention. The aforementioned method may be carried out using the aforementioned system aspect of the invention.

[0063] The features of the same and/or of different aspects as described above and herein can be combined with each other and/or with the features described in the exemplary embodiments, except where mutually exclusive.

BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Features and advantages of the present invention will become apparent to those of ordinary skill in the art to which the invention pertains from a reading of the following description together with the accompanying drawings, in which:

[0065] FIG. l is a schematic representation of a conventional system for winding a plurality of strands, particularly glass fiber strands, into a cake or the like;

[0066] FIG. 2 is a schematic representation of a conventional process of winding a roving assembly using multiple fiber strands taken from multiple cakes of the type represented in FIG. 1;

[0067] FIG. 3 is a schematic illustration of two fiber strands matchsticking at two locations resulting in a catenary between the two locations;

[0068] FIG. 4A is a schematic illustration of an exemplary strand guide showing a strand engaging member in a first position;

[0069] FIG. 4B is a schematic illustration of the strand guide of FIG. 4A showing the strand engaging member in a second position;

[0070] FIG. 5A is a schematic illustration of two fiber strands that have been matchsticked at multiple locations by the strand guide of FIGS. 4A-4B;

[0071] FIG. 5B is a schematic cross-sectional illustration of two fiber strands that have been matchsticked by the strand guide of FIGS. 4A-4B; [0072] FIG. 6A is a schematic illustration of an exemplary strand pattern produced by the strand guide of FIGS. 4A-4B;

[0073] FIG. 6B is a schematic illustration of an exemplary strand pattern produced by the strand guide of FIGS. 4A-4B;

[0074] FIG. 7 is a schematic illustration of an exemplary separating device including a strand guide according to the present invention;

[0075] FIG. 8 is a side view of the strand guide of FIG. 7;

[0076] FIG. 9A is a schematic illustration of a fiber winding system with the strand guide of FIG. 7 in a first rotational position while in a first position;

[0077] FIG. 9B is a schematic illustration of a fiber winding system of FIG. 9A with the strand guide in a second rotational position while in the first position;

[0078] FIG. 9C is a schematic illustration of a fiber winding system of FIG. 9A with the strand guide in a third rotational position while in the first position;

[0079] FIG. 9D is a schematic illustration of a fiber winding system of FIG. 9A with the strand guide in a fourth rotational position while in the first position;

[0080] FIG. 9E is a schematic illustration of a fiber winding system of FIG. 9A with the strand guide in a second position;

[0081] FIG. 9F is an exemplary process diagram illustrating positions of the strand guide in a fiber winding process.

[0082] FIG. 10 is a side view of an example traversing apparatus of the fiber winding system of FIG. 9 A;

[0083] FIG. 11 is a schematic illustration of the curvature of a bar of the traversing apparatus of FIG. 10; and

[0084] FIG 12 is a side view of an example traversing apparatus of the fiber winding system of FIG. 9 A.

DETAILED DESCRIPTION

[0085] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which these exemplary embodiments and examples belong. The terminology used in the description herein is for describing exemplary embodiments and examples only and is not intended to be limiting of the exemplary embodiments or examples. Accordingly, the general inventive concepts are not intended to be limited to the specific embodiments or examples illustrated herein. Although other configurations and methods similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred configurations and methods are described herein.

[0086] As used in the specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0087] Unless otherwise indicated, all numbers expressing physical and measured attributes used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present exemplary embodiments. At the very least each numerical parameter should be construed in light of the number of significant digits and ordinary rounding approaches.

[0088] Unless otherwise indicated, any element, property, feature, or combination of elements, properties, and features, may be used in any embodiment or example disclosed herein, regardless of whether the element, property, feature, or combination of elements, properties, and features was explicitly disclosed in the embodiment or example. It will be readily understood that features described in relation to any particular aspect described herein may be applicable to other aspects described herein provided the features are compatible with that aspect. In particular: features described herein in relation to the method may be applicable to the product and vice versa.

[0089] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the exemplary embodiments and examples are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Every numerical range given throughout this specification and claims will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.

[0090] The present disclosure is directed to a strand guide for use in a system for winding fiber strands, such as for example, glass fibers, into a cake or the like. The strand guide is configured to selectively engage the fiber strands, continuously or discontinuously, to control the number and size of loops created by controlling strand matchsticking (e.g., by forcing periodic strand matchsticking). The strand matchsticking may include comingling filaments of a first strand with filaments of at least a second strand. [0091] FIGS. 4A and 4B schematically illustrate an example strand guide 202 for use in a fiber strand winding system, such as the conventional glass fiber strand winding system 100 schematically illustrated in FIG. 1. The strand guide 202 is positioned to selectively contact one or more glass fiber strands 210 downstream of a separating device 208 (e.g., comb), such as for example, the conventional separating device 108 of FIG. 1, and upstream of a traversing apparatus (not shown), such as for example, the conventional traversing apparatus 116 of FIG. 1. The strand guide 202 generally functions by selectively causing the two or more glass fiber strands 210 to contact each other to facilitate the two or more glass fibers strands 210 sticking together, for example, by causing filaments of the two or more strands 210 to become comingled.

[0092] The strand guide 202 can be configured in a variety of ways. In the illustrated example of FIGS. 4A and 4B, the strand guide 202 is positioned adjacent the plurality of fiber strands 210 and includes a strand engaging member 204. The strand engaging member 204 is movable between a first position, illustrated in FIG. 4A with the strand engaging member 204 in solid lines, and a second position, illustrated in FIG. 4B with the strand engaging member 204 in dashed lines. In the first position, the strand engaging member 204 engages the plurality of fiber strands 210 causing two or more glass fiber strands 210 to contact each other. In the second position, the strand engaging member 204 is disengaged from (i.e., not in contact with) the plurality of fiber strands 210. The strand engaging member 204 can move between the first position and the second position in any suitable way. For example, the strand engaging member 204 can be moved rotationally into and out of the first position or can translate back and forth between the first and second position.

[0093] Referring to FIG. 4 A, the strand engaging member 204 can include one or more strand engaging surfaces 206. Each of the one or more strand engaging surfaces 206 can be configured to cause two or more fiber strands 210 to contact each other. As shown in FIG. 4 A, the two or more fiber strands 210, once in contact, can stick together over a length. For example, FIGS. 4 A and 4B illustrate nine (9) fiber strands 210 coming from the separating device 208. When the strand engaging member 204 is in the second position, as shown in FIG. 4B, the nine (9) fiber strands 210 are not engaged by the strand engaging member 204 and are illustrated as not sticking together (i.e., remain as nine (9) fiber strands). When the strand engaging member 204 is in the first position, however, the strand engaging member 204 contacts the plurality of fiber strands 210 causing some of the fiber strands to contact an adjacent fiber strand. As a result, some of the fiber strands 210 stick together (“matchstick”). In the example of FIG. 4A, four (4) of the nine (9) fiber strands are brought into contact with, and stick to, an adjacent fiber strand. As a result, over the length that the fiber strands stick together, the number of fiber strands 210 is reduced to five (5) strands, as shown in FIG. 4A.

[0094] When the strand engaging member 204 moves back to the second position and out of contact with the plurality of fiber strands 210, the fiber strands tend to unstick and return to the spacing established by the separating device (i.e., to nine (9) fiber strands). The strand guide 202 can move the strand engaging member 204 back and forth between the first position and the second position to cause controlled matchsticking of the fiber strands.

[0095] FIG. 5A schematically illustrates the forced matchsticking of two fiber strands. Like FIG. 3, a longer strand 230 is shown stuck to a shorter strand 232 at multiple locations along the length of the short strand 232. In FIG. 5A, the longer strand 230 is illustrated as sticking to the shorter strand 232 at a first location 234, a second location 236, a third location 238, and a fourth location 240. Due to the excess length of the longer strand 230, the longer strand 230 forms a first loop or catenary 242 between the first location 234 and the second location 236, a second loop or catenary 244 between the second location 236 and the third location 238, and a third loop or catenary 246 between the third location 238 and the fourth location 240. Unlike FIG. 3, however, a distance between the first location 234 and the second location 236, the second location 236 and the third location 238, and so on is relatively small and/or consistent. Therefore, the loops or catenaries 242, 244, 246 between the locations is controlled to be relatively small and/or consistent. Thus, unlike the problematic matchsticking that occurs randomly in conventional winding systems, the example strand guide 202 controls the matchsticking phenomenon in a manner that mitigates potential defects.

[0096] FIG. 5B schematically illustrates a cross-sectional view of matchsticking of two fiber strands. For example, the strands may be a longer strand 230 stuck to a shorter strand 232 at a first location 234. In the embodiment of FIG. 5B, a strand guide 250 has a pair of teeth comprising a first tooth 252a and a second tooth 252b. The teeth 252a, 252b define a groove 254 therebetween. The strands 230, 232 contact the groove 254 (i.e., the inner walls of the teeth 252a, 252b) and slide down toward a bottom 256 of the groove 254. As the strands 230, 232 slide down, the filaments comprising the strands 230, 232 may spread apart due to friction between the strands and the walls of the teeth. As the strands 230, 232 approach the bottom of the groove, the strand 230, 232 are forced into contact with each other. This contact may cause filaments of the strands 230, 232 to comingle with each other. Spreading of the filaments while the strands 230, 232 slide down the groove may further promote comingling as less-densely packed filaments more readily accept other filaments in gaps therebetween. Such contact and/or comingling results in matchsticking of the strands 230, 232 at the first location 234. [0097] With continued reference to FIG. 5B, the first and second teeth 252a, 252b have a pitch P (i.e., an opening width of the groove 254). In some examples, the pitch P may be sized such that the groove 254 receives the strands 230, 232, and, for example, only the strands 230, 232 and no other strands. The pitch P may be greater than a pitch between the strands 230, 232. The pitch P may be in the range of about 1 mm to about 50 mm, in the range of about 3 mm to about 20 mm, in the range of about 5 mm to about 15 mm, in the range of about 6 mm to about 12 mm, etc.

[0098] With continued reference to FIG. 5B, the groove 254 has an opening angle 6 (i.e., an angle between the inner walls of the teeth 252a, 252b). The opening angle 6 may be configured to maximize spreading of the filaments of the strands 230, 232 as they slide down the inner walls of the teeth 252a, 252b while minimizing the space required to fit the strand guide in a processing area. In some examples the opening angle 6 is less than 180 degrees, less than 120 degrees, less than 90 degrees, less than 60 degrees, less than 45 degrees, etc. In some examples the opening angle 6 is in the range of about 10 degrees to about 70 degrees, in the range of about 20 degrees to about 60 degrees, in the range of about 35 degrees to about 45 degrees, etc. [0099] With continued reference to FIG. 5B, the shape of the bottom 256 of the groove 254 may be configured to force the strands 230, 232 into contact with each other and/or to comingle filaments of said strands. In some examples, the bottom 256 of the groove 254 has a V-shape, truncated V-shape, U-shape, or rounded V-shape, as shown in FIG. 5B. In some examples, the bottom 256 of the groove 254 has a curvature having a radius R. A diameter of the bottom 256 of the groove 254 (i.e., twice the radius R) may be substantially equal to or lesser than a sum of diameters of the strands 230, 232. In other words, the strands 230, 232 may be forced together at the bottom 256 of the groove 254 since the bottom 256 is not wide enough to fit the strands 230, 232 merely sitting side-by-side without any comingling of filaments. In some examples, the radius R may be less than about 1 mm, such as in the range of about 0.01 mm to about 0.5 mm, in the range of about 0.1 mm to about 0.4 mm, in the range of about 0.2 mm to about 0.3 mm, etc.

[00100] In some examples, the strand guide 202 can include one or more additional strand engaging members. For example, a second strand engaging member (not shown) can be configured to engage the plurality of fiber strands 210 in a similar manner as the illustrated strand engaging member 204 but at a time the illustrated strand engaging member 204 is in the second position. In some examples, the second strand engaging member (not shown) can cause different fiber strands to matchstick together than the illustrated strand engaging member 204. FIG. 6A illustrates an example pattern of the glass fiber strands resulting from the forced matchsticking of the strand guide 202. As shown, the pattern alternates between nine (9) fiber strands S9 [604] and five (5) fiber strands S5 [606] and alternates between which glass fiber strands 210 are matchsticked together.

[00101] In some examples, the strand guide 202 can move between a first position proximal to the fiber strands (i.e., an on-line position) and a second position distal to the fiber strands (i.e., an off-line position). For example, with reference to FIGS. 4A-4B, the strand guide 202 can move (e.g., translate, slide, swing, etc.) between the first position and the second position. While the guide 202 is in the first position, at least one of the strand engaging members is configured to engage the strands (e.g., comingle filaments of the fiber strands).

[00102] In examples, the strand engaging member 204 and a second strand engaging member (not shown) are rotatable, such as about a central axis extending along a length of the strand guide 202. While the strand guide 202 is in the second position, the strand engaging members are positioned too far from the fiber strands to contact the fiber strands, regardless of a rotational position of the strand engaging members. In other words, the distance from the strand guide 202 (e.g., from the central axis of the guide 202) is greater than a length (e.g., a maximum radial length) of the strand engaging member 204 and/or the second strand engaging member. While the guide 202 is in the second position, rotation of the guide 202 and the strand engaging members may be stopped or the guide and strand engaging members may rotate (e.g., the guide may continuously rotate regardless of being in the first or second position).

[00103] While the strand guide 202 is in the first position, the strand engaging members are positioned closely enough to the fiber strands such that one of the strand engaging members may contact the fiber strands upon the members being rotated into a rotated position. In other words, while in the first position, the distance from the strand guide 202 is lesser than a length of the strand engaging member 204 and/or the second strand engaging member.

[00104] While the guide 202 is in the first position, the guide 202 and strand engaging members may rotate, for example, such that the strand engaging members engage with the fiber strands in a cyclical and/or alternating fashion. In examples, while the strand guide 202 is in the first position, the guide 202 first rotates such that the strand engaging member 204 engages the strands 210. Second, the guide 202 rotates such that none of the strand engaging members engage the strands 210. Third, the guide 202 rotates such that the second strand engaging member engages the strands. Fourth, the guide 202 rotates such that none of the strand engaging members engage the strands 210. These four steps may be repeated during a period of time when alternating matchsticking of the strands 210 is desired (i.e., during a matchsticking period). When matchsticking of the strands 210 is no longer desired, the guide 202 may move from the first position to the second position such that the strand engaging members do not engage the strands (i.e., during a non-matchsticking period). One instance of the matchsticking period and one instance of the non-matchsticking period may constitute a cycle. When matchsticking of the strands 210 is again desired, the guide 202 may move from the second position to the first position such that the strand engaging members are engageable with the strands. This cycle of moving between the first and second positions may be repeated continuously, such as during a continuous fiber production and packaging process. Thus, the strands 210 may be selectively matchsticked in a cyclical process.

[00105] In examples, while the strand guide 202 is in the first position, the strand engaging member 204 is rotatable to a first rotated position wherein the member 204 is engaged with at least some of the fiber strands 210. In the first rotated position, the engaging member 204 extends from the guide 202 in a direction toward and substantially perpendicular to the strands 210. In other words, the strand guide is rotatable to a first rotated position wherein the strand engaging member (e.g., first comingling member) is proximal to and substantially perpendicular to the fiber strands. While the member 204 is in the first rotated position, the second strand engaging member may not engage the strands 210, for example, because the strand engaging member extends from the guide 202 in a direction away from the strands.

[00106] In examples, while the strand guide 202 is in the first position, the second strand engaging member is rotatable to a second rotated position wherein the second strand engaging member is engaged with at least some of the fiber strands 210. In the second rotated position, the second engaging member extends from the guide 202 in a direction toward and substantially perpendicular to the strands 210. In other words, the strand guide is rotatable to a second rotated position wherein the second strand engaging member (e.g., second comingling member) is proximal to and substantially perpendicular to the fiber strands. While the second strand engaging member is in the second rotated position, the first strand engaging member 204 may not engage the strands 210.

[00107] FIG. 6B illustrates an example pattern of the fiber strands resulting from the cyclical, selective matchsticking. As shown, the pattern alternates between nine (9) fiber strands along a non-matchsticked length 608 of the fiber strands and five (5) fiber strands 602 along a matchsticked length 602 of the fiber strands. Within the matchsticked length 602, the pattern alternates between which fiber strands are matchsticked together.

[00108] With continued reference to FIG. 6B, the non-matchsticked length 608 corresponds to a non-matchsticking period where the strand guide 202 is in the off-line, second position. The matchsticked length 602 corresponds to a matchsticking period where the strand guide 202 is in the on-line, first position. One instance of the matchsticking period and one instance of the non-matchsticking period may constitute a cycle. In examples, some amount of matchsticking may be desirable to compensate for or correct length variation between strands during winding. However, it may be desirable to limit the amount of matchsticking to only that amount necessary to compensate for length variation. It may be desirable to maximize the quantity of individual strands produced, and matchsticking strands together effectively reduces the quantity of individual strands produced. Accordingly, a ratio of the matchsticking period and the non-matchsticking period may be configured such that length variation amongst the strands is compensated or corrected while maximizing the quantity of individual strands. In examples, the non-matchsticking period is greater than the matchsticking period. In examples, the ratio of the non-matchsticking period to the matchsticking period is in the range of about 2: 1 to about 20: 1, in the range of about 4: 1 to about 10: 1, in the range of about 6: 1 to about 7: 1, etc.

[00109] With continued reference to FIG. 6B, focusing on split efficiencies of linear portions of the strands is another way to maximize the quantity of individual strands while ensuring length variation amongst the strands is adequately compensated or corrected. In examples, fiber strands have a split efficiency of up to about 100% upon exiting a separating device. In examples, the separating device separates filaments in to nine (9) fiber strands shown in the non-matchsticked length 608 of the fiber strands. During the non-matchsticking period, the split efficiency of the strands may be up to about 100%. In other words, the fiber strands have a first linear portion having a first split efficiency of up to 100%, where the first linear portion corresponds to the non-matchsticked length 608 of the fiber strands. During the matchsticking period (i.e., while the strand guide is in the on-line position), the strand guide engages the fiber strands and causes a second linear portion of the fiber strands to have a second split efficiency lesser than the first split efficiency. The second linear portion corresponds to the matchsticked length 602 of the fiber strands. The second split efficiency may be at least about 50%, up to about 80%, in the range of about 50% to about 80%, etc.

[00110] A length-weighted average split efficiency of the first linear portion and the second linear portion may be calculated by multiplying the first split efficiency with a first length of the first linear portion (e.g., matchsticked length 602) to generate a first length-weighted split efficiency, multiplying the second split efficiency with a second length of the second linear portion (e.g., non-matchsticked length 608) to generate a second length-weighted split efficiency, adding the first and second length-weighted split efficiencies to generate a first sum, and dividing the first sum by a second sum of the first length and second length (e.g., the combined length of the matchsticked length 602 and non-matchsticked length 608) to generate the length-weighted average split efficiency of the first linear portion and the second linear portion. In examples, the length-weighted average split efficiency may be at least about 80%, at least about 90%, at least about 95%, in the range of about 80% to about 95%, etc.

[00111] FIGS. 7-8 illustrate an example strand guide 302 for use in a fiber strand winding system 300 (FIGS. 9A-9E), such as the conventional glass fiber strand winding system 100 schematically illustrated in FIG. 1. The strand guide 302 is positioned to selectively contact, continuously or discontinuously, one or more glass fiber strands 310 downstream of a separating device 308 (e.g., comb) and upstream of a traversing apparatus 315 (FIGS. 9A-9E). The strand guide 302 generally functions by selectively causing the two or more glass fiber strands to contact each other to facilitate the two or more glass fibers strands sticking together. In the illustrated example of FIGS. 7-8, the strand guide 302 is mounted on a mounting assembly (not shown) adjacent the separating device 308. In some examples, the mounting assembly can also mount the separating device 308.

[00112] The strand guide 302 can be configured in a variety of ways. Any configuration capable of selectively causing the two or more glass fiber strands to contact each other to facilitate the two or more glass fibers strands sticking together may be used. In the illustrated example, the strand guide 302 has a first strand engaging member 304 and a second strand engaging member 306. In other examples, the strand guide 302 can have a single strand engaging member or greater than two strand engaging members.

[00113] The first strand engaging member 304 has an elongated, thin, flat body 307 (e.g., resembling a comb) extending along a longitudinal axis F. The body 307 has a proximal end 318, a distal end 320 opposite the proximal end 318, a first side 322 extending between the proximal end 318 and the distal end 320, and second side 324 opposite the first side end and extending between the proximal end 318 and the distal end 320. The first strand engaging member 304 includes a plurality of teeth 314 spaced apart to form grooves 316 therebetween. The plurality of teeth 314 can extend radially outward from the proximal end 318 to the distal end 320. In the illustrated example, the plurality of teeth 314 extend parallel to each other in series along the longitudinal axis F. In some examples, the teeth 314 are configured such that the grooves 316 become narrower closer to the proximal end 318 (e.g., the grooves taper inward) to facilitate the fiber strands 310 within each groove 316 contacting each other.

[00114] In some examples, the number of the teeth 314 and the grooves 316, and the spacing and location of the teeth 314 and the grooves 316, is coordinated with the spacing and number of the glass fiber strands 310 coming to the strand guide 302 from the separating device 308 (FIGS. 9A-9E). For example, the separating device 308 may be a comb having several teeth 328. The number of the teeth 328 and the spacing of the teeth 328 dictate the number of fiber strands 310 and the spacing of the fiber strands 310 received by strand guide 302.

[00115] The strand guide 302 includes a base 330 to which the first and second strand engaging members 304, 306 attach or are integrally formed therewith. The base 330 may be configured in a variety of ways. In the illustrated example, the base 330 is configured as an elongated cylinder or tube that is rotatable about the longitudinal axis F by conventional mechanical drive means, such as a motor (not shown). The first and second strand engaging members 304, 306 can attach to the base 330 in any suitable manner, such as, but not limited to, welding, fasteners, interference fit, tongue and groove, or other suitable connecting method. The base 330 and strand engaging members 304, 306 may also be a unitary body (i.e., integrally forming the strand guide 302).

[00116] The second strand engaging member 306 is configured substantially similar to the first strand engaging member 304 and can attach to the base 330 in the same manner (i.e., via a second longitudinal groove 337. Thus, the description of the first strand engaging member 304 applies equally to the second strand engaging member 306. The second strand engaging member 306 includes a plurality of teeth 344 spaced apart to form grooves 346 therebetween. In some examples, the grooves 346 in the second strand engaging member 306 are axially offset from the grooves 316 in the first strand engaging member 304 such that the forced matchsticking occurs between different glass fiber strands 310 than with first strand engaging member 304.

[00117] In some examples, the strand guide 302 comprises a first comingling member (e.g., first strand engaging member 304) extending from the strand guide 302. The strand guide may comprise a second comingling member (e.g., second strand engaging member 306) extending from the strand guide 302, for example, in a direction substantially opposite the first comingling member. The first comingling member may include a first pair of teeth (e.g., comprising the plurality of teeth 314 of the first strand engaging member 304) defining a first groove (e.g., one of the grooves 316 of the first strand engaging member 304) between the first pair of teeth. The second comingling member may include a second pair of teeth (e.g., comprising the plurality of teeth 344 of the second strand engaging member 306) defining a second groove (e.g., one of the grooves groove 346 of the second strand engaging member 306) between the second pair of teeth. [00118] In some examples, the first and second pairs of teeth are at least partially offset from one another along an axial length of the strand guide. In some examples, the first and second pairs of teeth are offset from one another such that the first groove is substantially aligned with a tooth of the second pair of teeth. Furthermore, the pairs of teeth may be offset such that the second groove is substantially aligned with a tooth of the first pair of teeth. In such a configuration, the first comingling member matchsticks different strands of the plurality of strands 310 than that of the second comingling member.

[00119] In some examples, the first groove of the first comingling member may be configured to bring a first fiber strand and a second fiber strand into contact with each other and may further cause comingling of at least some of filaments of the first fiber strand with at least some of filaments of the second fiber strand. As described herein, the strand guide 302 and/or the comingling members (e.g., the strand engaging members 304, 306) may be rotatable. Accordingly, the strand guide 302 may be configured such that the first comingling member causes contact between and/or comingling of filaments of the first and second fiber strands while the strand guide is in a first rotated position.

[00120] In some examples, the second groove of the second comingling member may be configured to bring the second fiber strand and a third fiber strand into contact with each other and may further cause comingling of at least some of filaments of the second fiber strand with at least some of filaments of the third fiber strand. The strand guide 302 may be configured such that the second comingling member causes contact between and/. or comingling of filaments of the second and third fiber strands while the strand guide is in a second rotated position. In some examples, the first and second rotated positions are separated by about 180 degrees of rotation about a central axis of the strand guide 302.

[00121] In some examples, the strand guide 302 and/or the comingling members is rotatable to a third rotated position wherein none of the first, second, and third fiber strands are caused to contact or comingle with one another. For example, the strand guide 302 may be rotatable to the third position wherein the first and second comingling members are substantially parallel to the fiber strands 310.

[00122] In the illustrated example. The second strand engaging member 306 is mounted 180 degrees around the periphery of the base 330 from the first strand engaging member 304. Thus, the second strand engaging member 306 is opposite the first strand engaging member 304. Further, as shown in FIG. 8, the first strand engaging member 304 and the second strand engaging member 306 are coplanar. In other examples, however, the first and second strand engaging member may be positioned and oriented other than coplanar and at an angle to one another that is different from 180 degrees.

[00123] The first strand engaging member 304 and the second strand engaging member 306 when mounted on the rotatable base 330 will rotate therewith. In particular the first strand engaging member 304 will move between a first position in which the first strand engaging member 304 engages the plurality of fiber strands 310 causing the two or more glass fiber strands 310 to contact each other and a second position in which the first strand engaging member 304 is disengaged from (i.e., not in contact with) the plurality of fiber strands 310. Likewise, the second strand engaging member 306 will move between a third position in which the second strand engaging member 306 engages the plurality of fiber strands 310 causing the two or more glass fiber strands 310 to contact each other and a fourth position in which the second strand engaging member 306 is disengaged from (i.e., not in contact with) the plurality of fiber strands 310.

[00124] FIGS. 9A-9E schematically illustrate the winding system 300 with the strand guide 302 positioned between the separating device 308 and the traversing apparatus 315. Each of FIGS. 9A-9E illustrate both a side view and a front view of the strand guide 302 relative to the plurality of fiber strands 310. A plurality of fiber strands 310 are shown extending from the separating device 308 to the traversing apparatus 315. In the illustrated example, the separating device 308 forms nine (9) discrete fiber strands 310.

[00125] Referring to FIG. 9A, the strand guide 302 is in a first rotational position. In the first rotational position, the first strand engaging member 304 is in a non-engaging position (i.e., the second position) and the second strand engaging member 306 is in a non-engaging position (i.e., the fourth position). In the illustrated example, the first strand engaging member 304 and the second strand engaging member 306 extend generally parallel to and spaced apart from the fiber strands 310 that pass adjacent the strand guide 302. In particular, the teeth 314 of the first strand engaging member 304 extend upward and the teeth 344 of the second strand engaging member 306 extend downward. Thus, in the first rotational position, the fiber strands 310 are not engaged by the strand guide 302 and the traversing apparatus 315 receives nine (9) fiber strands 310.

[00126] Referring to FIG. 9B, the strand guide 302 is in a second rotational position. In the second rotational position, the first strand engaging member 304 is in an engaging position (i.e., the first position) and the second strand engaging member 306 is in a non-engaging position (i.e., the fourth position). In particular, the teeth 344 of the second strand engaging member 306 extend away from the fiber strands 310 and the teeth 314 of the first strand engaging member 304 extend toward the fiber strands 310 such that nine (9) fiber strands 310 are received within the grooves 316. As a result, in some of the grooves 316, two glass fiber strands 310 are received in the same groove 316. In those grooves 316, the two retained glass fiber strands 310 contact each other and stick together (e.g., due to comingling of filaments of the strands 310). In the illustrated example, four pairs of fiber strands 310 stick together resulting in the traversing apparatus 315 receiving five (5) fiber strands 310.

[00127] Referring to FIG. 9C, the strand guide 302 is in a third rotational position. In the third rotational position, the first strand engaging member 304 is in a non-engaging position (i.e., the second position) and the second strand engaging member 306 is in a non-engaging position (i.e., the fourth position). In the illustrated example, the first strand engaging member 304 and the second strand engaging member 306 extend generally parallel to and spaced apart from the fiber strands 310 that pass adjacent the strand guide 302. In particular, the teeth 314 of the first strand engaging member 304 extend downward and the teeth 344 of the second strand engaging member 306 extend upward. Thus, in the third rotational position, the fiber strands 310 are not engaged by the strand guide 302 and the traversing apparatus 315 receives nine (9) fiber strands 310.

[00128] Referring to FIG. 9D, the strand guide 302 is in a fourth rotational position. In the fourth rotational position, the first strand engaging member 304 is in a non-engaging position (i.e., the second position) and the second strand engaging member 306 is in an engaging position (i.e., the third position). In particular, the teeth 314 of the first strand engaging member 304 extend away from the fiber strands 310 and the teeth 344 of the second strand engaging member 306 extend toward the fiber strands 310 such that the fiber strands 310 are received within the grooves 346. As a result, in some of the grooves 346, two (2) glass fiber strands 310 are received in the same groove 346. In those grooves 346, the two (2) retained glass fiber strands 310 contact each other and stick together. In the illustrated example, four pairs of fiber strands 310 stick together resulting in the traversing apparatus 315 receiving five (5) fiber strands 310. As shown in FIGS. 9B and 9D because the grooves 316 are axially offset relative to the grooves 346, the forced matchsticking caused by the first strand engaging member 304 occurs between different glass fiber strands 310 than with the second engaging member 306.

[00129] While FIGS. 9A-9D generally show the strand guide 302 in a first position proximal to the fiber strands 310, FIG. 9E illustrates that, in some examples, the strand guide 302 is movable to a second position distal to the fiber strands. As described herein, while in the first position, the strand guide 302 may altematingly matchstick the strands 310 with the first and second strand engaging members 304, 306 as the strand guide 302 rotates around its central axis. Thus, the first position may be referred to as an “on-line” position. However, while in the second position, the strand guide 302 may be too far from the strands 310 for the first and second strand engaging members 304, 306 to contact the strands. Thus, the second position may be referred to as an “off-line” position. For example, a distance from the strand guide 302 (e.g., the central axis of the guide 302) to the strands 310 may be greater than a length of the strand engaging members 304, 306. The strand guide 302 may be movable between the first position and second position in any suitable manner (e.g., translating, sliding, swinging, etc.). The strand guide 302 may continue rotating while in the second position, or the strand guide 302 may cease rotating while in the second position and resume rotating before or upon returning to the first position.

[00130] FIG. 9F is an exemplary process diagram illustrating the on-line and rotated positions of the strand guide 302 as shown in FIGS. 9A-9D and the off-line position of the strand guide 302 as shown in FIG. 9E. In some examples, a matchsticking period 902 (i.e., a duration of time while the strand guide 302 is in the on-line or first position proximal to the strands 310) corresponds to a matchsticked length 602 as shown in FIG. 6B. A non-matchsticking period 908 (i.e., a duration of time while the strand guide 302 is in the off-line position) may correspond to a non -matchsticked length 608 as shown in FIG. 6B. With continued reference to FIG. 9F, one instance of the matchsticking period 902 and one instance of the nonmatchsticking period 908 may constitute a cycle 910, which may be repeated continuously.

[00131] In some examples, the matchsticking period 902 includes a first on-line position Pl that may correspond to the first rotated position of the strand guide 302 as shown in FIG. 9 A. In some examples, the matchsticking period 902 includes a second on-line position P2 that may correspond to the second rotated position of the strand guide 302 as shown in FIG. 9B. In some examples, the matchsticking period 902 includes a third on-line position P3 that may correspond to the third rotated position of the strand guide 302 as shown in FIG. 9C. In some examples, the matchsticking period 902 includes a fourth on-line position P4 that may correspond to the fourth rotated position of the strand guide 302 as shown in FIG. 9D. In some examples, the non-matchsticking period 908 includes an off-line position P0 that may correspond to the second position of the strand guide 302 as shown in FIG. 9E (i.e., where the strand guide 302 is distal to the strands 310). As FIG. 9F indicates, the strand guide 302 may be movable from the off-line position P0 to any of the on-line positions Pl, P2, P3, P4. Furthermore, the strand guide 302 may be movable (e.g., rotatable) between the on-line positions Pl, P2, P3, P4. Further yet, the strand guide 302 may be movable from any of the on-line positions Pl, P2, P3, P4 to the off-line position P0. [00132] FIG. 10 illustrates an example traversing apparatus 415 for the fiber strand winding system 300. The traversing apparatus 415 is configured to laterally displace the glass fiber strands received from the strand guide 302 along an axial length of the spindle 112 to distribute the glass fiber strands during winding. Winding the strands along the axial length of the spindle 112 forms a cake having an axial length that may correspond to a travel range of the traversing apparatus 415 as it laterally displaces the strands along the axial length of the spindle 112. As described herein, one instance of a matchsticking period and one instance of a nonmatchsticking period may constitute a cycle. A time duration of the cycle may correspond to a time duration of the traversing apparatus 415. In some examples, the time duration of the cycle corresponds to the traversing apparatus 415 traveling about twice the axial length of the cake (i.e., a duration of time that passes while the traversing apparatus 415 travels from a first axial end of the cake to a second axial end of the cake and then travels from the second axial end back to the first axial end).

[00133] With continued reference to FIG. 10, the traversing apparatus 415 can be configured in a variety of ways. Any type of traversing apparatus that can laterally displace glass fiber strands received from the strand guide 302 along an axial length of the spindle 112 to distribute the glass fiber strands during winding can be used. In some embodiments, the traversing apparatus 415 is similar to the traversing apparatus disclosed in U.S. Pat Pub. No. 2012/0167634 (hereinafter “the ‘634 publication”), the entire disclosure of which is fully incorporated herein by reference.

[00134] In general, the traversing apparatus 415 is mounted on a shaft 450 rotatable about axis of rotation X and includes opposing first and second bar supports 422a, 422b. The first and second bar supports 422a, 422b can be generally parallel with one another and are preferably, but not necessarily, skewed relative to the shaft 450. One or more of the first and second bar supports 422a, 422b may be configured to engage and move the strands in a first direction relative to the axis of rotation X of the traversing apparatus 415 (e.g., toward a first axial end of the traversing apparatus 415). This movement of the strands may be achieved by skewing the support 422a and/or 422b relative to the shaft 450. In other words, skewing the support 422a and/or 422b creates a slope toward an axial end of the shaft 450, and, since the strands 310 may be under tension during the winding process, the strands 310 may slide down the slope toward the axial end of the shaft 450. The supports 422a and 422b may slope toward opposite axial ends of the shaft 450, such as in an embodiment where the supports 422a, 422b are generally parallel to each other. Accordingly, the first bar support 422a may be configured to engage and move the strands in the first direction and the second bar support 422b may be configured to engage and move the strands in a second direction relative to the axis of rotation X of the traversing apparatus 415 (e.g., toward a second axial end opposite the first axial end of the traversing apparatus 415). Moreover, the first and second bar supports 422a, 422b are made of any suitable rigid material suitable for the operating environment, such as metal (e.g., aluminum). As further described herein, the first and second bar supports 422a, 422b may be curved radially inward toward the axis of rotation of X of the traversing apparatus 415. In some examples, the first and/or second bar supports 422a, 422b may be curved radially inward such that a central portion of the first and/or second bar supports 422a, 422b is more proximal to the axis of rotation X of the traversing apparatus 415 than end portions of the first and/or second bar supports 422a, 422b.

[00135] A plurality of bars extends between respective peripheries of the first and the second bar supports 422a, 422b. More specifically, a pair of first bars 424a, 424b extend between the first bar support 422a and the second bar support 422b and are arranged opposite one another (i.e., on opposite sides of the rotatable shaft 450). Similarly, a pair of second bars 425a, 425b, a pair of third bars 426a, 426b, and a pair of fourth bars 427a, 427b extend between the first bar support 422a and the second bar support 422b. The bars of each pair of bars are arranged opposite one another (i.e., on opposite sides of the rotatable shaft 450). Thus, the illustrated traversing apparatus 415 includes eight bars extending between the bar supports. In other embodiments, however, the number of bars extending between the bar supports can be more or less than eight bars.

[00136] In some embodiments, the bars are configured with the similar geometric conditions (e.g., positive or negative slope, arranged relative to one another to lie on the surface of a cone), as the bars described in the ‘634 publication and will not be disclosed in detail below. A difference between the traversing apparatus 415 and the traversing apparatus disclosed in the ‘634 publication is that some of the bars in traversing apparatus 415 are curved. Which bars are curved, the number of bars that are curved, the direction of curvature, and the amount of curvature can vary in different embodiments.

[00137] In the illustrated embodiment, the first pair of bars 424a, 424b, the third pair of bars 426a, 426b, and the fourth pair of bars 427a, 427b are curved radially inward, while the second pair of bars 425a, 425b are linear. For example, the first, third, and/or fourth pairs of bars may be curved radially inward toward the Referring to FIG. 11, the first bar 424a of the first pair of bars is an example illustrating the curvatures of the bars. In particular, the bar 424a has a first end 430 and a second end 432 opposite the first end 430. In the illustrated embodiment, the bar 424a is symmetrically curved about a midpoint M of the bar 424a. In other words, the curvature of the bar 424a is substantially symmetrical about a central axis that bisects the curvature. The curvature of the bar 424a is measured by the distance D that the midpoint M is displaced from a straight-line SL connecting the first end 430 and the second end 432. In some embodiments, the bar 424a has a curvature distance D of 15-50 mm, or 25-45 mm, or 25-40 mm, or 30-42 mm, or 35-40 mm. In some embodiments, the curvature of each of the pair of bars can differ from the curvature of the other pairs of bars. In other embodiments, the curvature of the one or more of the pair of bars can be the same or similar to the curvature of one or more of the other pair of bars.

[00138] The curvature of the first pair of bars 424a, 424b, the third pair of bars 426a, 426b, and the fourth pair of bars 427a, 427b in the above ranges has shown to reduce the distance between glass fiber strands received from the strand guide 302 on the traversing apparatus 415, and subsequently on the cake 114, as compared to straight bars. Further, the traversing apparatus 415 with the curved bars reduces the distance (i.e., the bandwidth) of the strands on the traversing apparatus 415 without the glass fiber strands contacting each other.

[00139] FIG. 12 illustrates an example traversing apparatus 515 for the fiber strand winding system 300. The traversing apparatus 515 is configured to laterally displace the glass fiber strands received from the strand guide 302 along an axial length of the spindle 112 to distribute the glass fiber strands during winding. The traversing apparatus 515 can be configured in a variety of ways. Any type of traversing apparatus that can laterally displace glass fiber strands received from the strand guide 302 along an axial length of the spindle 112 to distribute the glass fiber strands during winding can be used.

[00140] In general, the traversing apparatus 515 is mounted on a shaft 550 rotatable about axis of rotation X and includes opposing first and second bar supports 522a, 522b. The first and second bar supports 522a, 522b can be generally parallel with one another and, in the illustrated example, are arranged perpendicular the shaft 550. The first and second bar supports 522a, 522b are made of any suitable rigid material suitable for the operating environment, such as metal (e.g., aluminum).

[00141] A plurality of bars extends between respective peripheries of the first and the second bar supports 522a, 522b. More specifically, a pair of first bars 524a, 524b extend between the first bar support 522a and the second bar support 522b and are arranged opposite one another (i.e., on opposite sides of the rotatable shaft 550). Similarly, a pair of second bars 525a, 525b extend between the first bar support 522a and the second bar support 522b and are arranged opposite one another (i.e., on opposite sides of the rotatable shaft 550). Thus, the illustrated traversing apparatus 515 includes four bars extending between the bar supports. [00142] In the illustrated embodiment, the first pair of bars 524a, 524b and the second pair of bars 525a, 525b are curved radially inward, similar to the curvature described above regarding the bar 424a. In some embodiments, the bars 524a, 524b, 525a, and 525b have a curvature distance D of 15-40 mm, or 20-35 mm, or 25-30 mm, or 30 mm. In some embodiments, the curvature of the first pair of bars 524a, 524b differs from the curvature of the second pair of bars 525a, 525b. In other embodiments, the curvature of the first pair of bars 524a, 524b can be the same or similar to the curvature of the second pair of bars 525 a, 525b.

[00143] The curvature of the first pair of bars 524a, 524b and the second pair of bars 525a, 525b, in the above ranges has shown to reduce the distance between glass fiber strands received from the strand guide 302 on the traversing apparatus 515, and subsequently on the cake 114, as compared to straight bars. Further, the traversing apparatus 515 with the curved bars reduces the distance (i.e., the bandwidth) of the strands on the traversing apparatus 515 without the glass fiber strands contacting each other.

[00144] Although the present disclosure has been described above with reference to certain examples for the purpose of illustrating and explaining the invention, it is to be understood that the invention is not limited solely by reference to the specific details of those examples. For example, while the winding system has been described as a system for winding glass fibers strands, the system can be used for winding other types of fibers and fiber strands. Thus, a person skilled in the art will readily appreciate that modifications and developments can be made in the preferred embodiments without departing from the scope of the invention as defined in the accompanying claims.

Claims

1. A strand guide for comingling a plurality of filaments of a plurality of fiber strands, the strand guide comprising: a first comingling member extending from the strand guide, and a second comingling member extending from the strand guide in a direction substantially opposite the first comingling member; wherein the first comingling member includes a first pair of teeth defining a first groove between the first pair of teeth, wherein the second comingling member includes a second pair of teeth defining a second groove between the second pair of teeth, and wherein the first and second pairs of teeth are at least partially offset from one another along a length of the strand guide.

2. The strand guide of claim 1, wherein the first and second pairs of teeth are offset from one another such that the first groove is substantially aligned with a tooth of the second pair of teeth and the second groove is substantially aligned with a tooth of the first pair of teeth.

3. The strand guide of any of the preceding claims, wherein the strand guide is movable between a first position proximal to the fiber strands and a second position distal to the fiber strands.

4. The strand guide of claim 3, wherein at least one of the first and second comingling members is configured to comingle the filaments of the fiber strands while the strand guide is in the first position.

5. The strand guide of claim 3 or 4, wherein the strand guide is in the first position for a first period of time and in the second position for a second period of time, and wherein one instance of the first period and one instance of the second period constitute a cycle.

6. The strand guide of claim 5, wherein the second period is greater than the first period.

7. The strand guide of claim 5, wherein a ratio of the second period to the first period is in the range of about 2: 1 to about 20: 1.

8. The strand guide of claim 7, wherein the ratio is in the range of about 4: 1 to about 10: 1.

9. The strand guide of claim 7, wherein the ratio is in the range of about 6: 1 to about 7: 1.

10. The strand guide of any of claims 3 to 9, wherein the fiber strands comprise a first linear portion having a first split efficiency of up to 100%, and wherein the strand guide causes a second linear portion of the fiber strands to have a second split efficiency in the range of about 50% to about 80% while the strand guide is in the first position.

11. The strand guide of claim 10, wherein a length-weighted average split efficiency of the first linear portion and the second linear portion is at least about 80%.

12. The strand guide of claim 11, wherein the length-weighted average split efficiency is at least about 90%.

13. The strand guide of claim 11, wherein the length-weighted average split efficiency is at least about 95%.

14. The strand guide of any of the preceding claims, wherein the strand guide is rotatable to a first rotated position wherein the first comingling member is proximal to and substantially perpendicular to the fiber strands.

15. The strand guide of claim 14, wherein the first groove is configured to bring a first fiber strand and a second fiber strand into contact with each other and comingle at least some of the filaments of the first fiber strand with at least some of the filaments of the second fiber strand while the strand guide is in the first rotated position.

16. The strand guide of any of the preceding claims, wherein the strand guide is rotatable to a second rotated position wherein the second comingling member is proximal to and substantially perpendicular to the fiber strands.

17. The strand guide of claim 16, wherein the second groove is configured to bring the second fiber strand and a third fiber strand into contact with each other and comingle at least some of the second filaments of the second fiber strand with at least some of third filaments of the third fiber strand while the strand guide is in the second rotated position.

18. The strand guide of any of the preceding claims, wherein the strand guide is rotatable to a third rotated position wherein the first and second comingling members are substantially parallel to the fiber strands.

19. A system for winding a plurality of strands comprising a fibrous material onto a spindle to form a cake, the system comprising: a plurality of filaments; a separating device configured to separate the filaments into groups, each of the groups corresponding to one of the strands; a spindle driven to rotate about a spindle axis of rotation, so that the strands are wound thereon; a traversing apparatus for displacing the strands in a reciprocating manner along an axial length of the spindle while the strands are wound on the spindle; and a strand guide positioned between the separating device and the traversing apparatus for selectively engaging the strands, wherein the strand guide is as described in any one of claims 1 to 18.

20. The system of claim 19, wherein the strand guide is as described in any one of claims 5 to 9, and wherein the cycle corresponds to the traversing apparatus traveling about twice an axial length of the cake.

21. The system of claim 19 or 20, wherein the traversing apparatus is rotatable about a traversing apparatus axis of rotation and comprises: a first bar configured to engage and move the strands in a first direction relative to the traversing apparatus axis of rotation, and a second bar configured to engage and move the strands in a second direction relative to the traversing apparatus axis of rotation, wherein the second direction is opposite the first direction; wherein the first bar and the second bar are curved radially inward toward the traversing apparatus axis of rotation such that central portions of the first and second bars are more proximal to the traversing apparatus axis of rotation than end portions of the first and second bars.

22. The system of claim 21, wherein the traversing apparatus further comprises a third bar disposed between the first bar and the second bar, and wherein the third bar is straight.

23. The system of claim 21 or 22, wherein at least one of the first bar and the second bar has a curvature in the range of about 15 mm to about 50 mm.

24. The system of claim 23, wherein the curvature is in the range of about 25 mm to about 45 mm.

25. The system of claim 23, wherein the curvature is in the range of about 30 mm to about 42 mm.

26. The system of claim 23, wherein the curvature is in the range of about 25 mm to about 40 mm.

27. The system of any one of claims 23 to 26, wherein the measure of the curvature of the at least one of the first bar and the second bar is a distance (D) that a midpoint (M) of the curvature is from a straight-line (SL) connecting a first end and a second end of the at least one of the first bar and the second bar.

28. The system of any one of claims 23 to 27, wherein the curvature of the at least one of the first bar and the second bar is substantially symmetrical about a central axis that bisects the curvature.

29. A method of winding fiber strands onto a spindle, the method comprising: providing filaments; separating the filaments into groups, each group of the filaments forming one of the fiber strands; rotating the spindle to wind the fiber strands onto the spindle; selectively engaging the fiber strands with a strand guide prior to winding fiber strands on the spindle to cause a first fiber strand and a second fiber strand of the fiber strands to contact each other; and displacing the fiber strands in a reciprocating fashion along an axial portion of the spindle while the fiber strands are being wound onto the spindle.

30. The method of claim 29, wherein causing the first fiber strand and the second fiber strand to contact each other further comprises causing at least some of first filaments of the first fiber strand to comingle with at least some of second filaments of the second fiber strand.

31. The method of claim 29 or 30, wherein selectively engaging the fiber strands further comprises rotating the strand guide to a first rotated position to cause the first fiber strand and the second fiber strand to contact each other.

32. The method of any of claims 29 through 31, wherein selectively engaging the fiber strands further comprises rotating the strand guide to a second rotated position to cause the second fiber strand and a third fiber strand of the fiber strands to contact each other.

33. The method of any of claims 29 through 32, wherein selectively engaging the fiber strands further comprises rotating the strand guide to a third rotated position to prevent any of the fiber strands from contacting each other.

34. The method of any of claims 29 through 33, wherein selectively engaging the fiber strands further comprises moving the strand guide between a first position proximal to the fiber strands in which the strand guide is engageable with the fiber strands and a second position distal to the fiber strands in which the strand guide is not engageable with the fiber strands.

35. The method claim 34, wherein the strand guide is in the first position for a first period of time and in the second position for a second period of time, and wherein one instance of the first period and one instance of the second period constitute a cycle.

36. The method of claim 35, wherein the second period is greater than the first period.

37. The method of claim 36, wherein a ratio of the second period to the first period is in the range of about 2: 1 to about 20: 1.

38. The method of claim 37, wherein the ratio is in the range of about 4: 1 to about 10: 1.

39. The method of claim 37, wherein the ratio is in the range of about 6: 1 to about 7: 1.

40. The method of any of claims 29 through 39, further comprising: forming the fiber strands to include a first linear portion having a first split efficiency of up to 100% while the strand guide is in the second position; and engaging a second linear portion of the fiber strands while the strand guide is in the first position such that the second linear portion has a second split efficiency in the range of about 50% to about 80%.

41. The method of claim 40, wherein a length-weighted average split efficiency of the first linear portion and the second linear portion is at least about 80%.

42. The method of claim 41 , wherein the length-weighted average split efficiency is at least about 90%.

43. The method of claim 41 , wherein the length-weighted average split efficiency is at least about 95%.