Method and arrangement for joining roving assemblies
Connecting the roving components through the spiral winding connection method solves the defect problems caused by conventional connections, achieving high-quality continuous supply of fiber raw silk, ensuring the smoothness and appearance quality of the product.
Patent Information
- Application Number
- CN202380090544.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-12-30
- Filing Date
- 2023-12-18
- Publication Date
- 2025-08-08
AI Technical Summary
Conventional transfer knots can easily lead to defects in the final product when connecting roving components, such as blocky or spherical fiberglass blocks, affecting the smoothness and appearance of the product.
By adopting a spiral winding connection method, the tail end portion of the first roving assembly is divided into a plurality of primary wires, and spirally wound around the front end portion of the second roving assembly, and is fixed by the main and secondary connecting parts to ensure that the connecting part is dispersed into separate chopped fibers when chopped.
Effectively avoid defects left by the connection part after short cutting, ensure the surface finish and appearance quality of the final product, and avoid visual discoloration or defects.
Smart Images
Figure CN120457083A_ABST
Abstract
Description
[0001] CROSS-REFERENCE TO RELATED APPLICATIONS
[0002] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 477,855, filed on December 30, 2022, the entire contents of which are incorporated herein by reference. Technical Field
[0003] The present invention relates to roving assemblies and, more particularly, to methods and fastening arrangements for operatively connecting fiber strands of a first roving assembly to fiber strands of a second roving assembly. Background Art
[0004] It is generally known in the art to wind elongated filaments or strands onto a rotating support to form a cake of wound material (sometimes also referred to in the art as a spool, package, reel, or roll). In the field of glass fiber materials, it is generally known to draw a plurality of glass fibers from a source of molten glass flowing through a bushing with a bushing periphery to obtain a relatively large number (e.g., one thousand) of glass fibers / to group a predetermined number of glass fibers to obtain corresponding glass fiber strands (sometimes referred to in the art as bundles). The one or more glass fiber strands are then wound onto a rotatable spindle having an axis of rotation to form a cake or spool.
[0005] Figure 1 It is the schematic diagram according to the conventional glass fiber precursor winding system 100 of foregoing.Bushel 102 (it can be a part for bushing) is a metal box-shaped structure, molten glass (from conventional molten glass source, not shown) flows through this metal box-shaped structure to form a plurality of (up to thousands of) independent glass filaments 104, and these glass filaments can be drawn (that is, pulling) by the remainder of this technique.Conventional sizing composition can optionally be deposited on glass filament 104 by conventional sizing device 106.In the example of conventional sizing device, long filament 104 can be through or adjacent sizing device 106 with for example, by making long filament 104 pass through with the surface (such as roller) of sizing composition moistening to deposit predetermined sizing composition.This sizing composition can be used for example to protect glass filament from being destroyed or improving the combination with reinforcing matrix in composite material.
[0006] Next, the filaments 104 are separated into several groups of filaments by a separator 108 to obtain discrete glass fiber strands 110, each glass fiber strand 110 having a plurality of filaments, each strand having up to about two hundred (200) filaments. Conventional separators 108 have, for example, a plurality of spaced-apart teeth, like a comb. Thus, each group of filaments is separated from the other groups by the teeth of the separator 108 to define a plurality of corresponding roughly planar glass fiber strands 110. One or more glass fiber strands 110 are then wound on a spindle or other elongated rotating support 112 to obtain a wound cake 114 of the glass fiber strands. It is known in the art to use a mechanical traverse device 116 to displace one or more glass fiber strands laterally along the axial length of the spindle 112 to distribute the glass fiber strands during winding, thereby obtaining a cake 114 that is evenly wound and, in particular, can be reliably unwound when needed. Figure 1 The mechanical traversing device in the spindle 112 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 manner back and forth along an axial portion of the spindle 112 while the glass fiber strands 110 are wound onto the spindle 112 to produce a uniform cake 114. The rotatably mounted spindle 112 is driven to rotate about the axis of rotation X' by conventional mechanical drive means, such as a motor (not shown here).
[0007] like Figure 2 As seen in FIG. 1 , once a number of cakes 114 are rolled, as shown in FIG. Figure 1 The plurality of corresponding glass fiber strands 110 shown wound around each cake 114 are thereafter drawn from the plurality of cakes 114, as shown. Figure 2 Several pluralities of glass fiber strands 110 drawn from a plurality of cakes 114 are then wound together to form a "roving assembly" 120 (sometimes referred to as a "multi-end" (referring to the aggregated grouping of discrete glass fiber strands) package or a "drop roll").
[0008] For example, in Figure 2 In one embodiment, the roving assembly 120 is a roving assembly having a plurality of roving fibers 110 wound therein. Each of the three (3) cakes 114 may include 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 is gathered together to form the roving assembly 120. Thus, the roving assembly 120 should provide thirty-six (36) glass fiber strands when unwound in subsequent use. The roving assembly 120 is typically used as a source of continuous glass fiber, for example, for the subsequent production of chopped glass fiber for use as composite material reinforcement (i.e., glass fiber is chopped and incorporated into a composite material to strengthen the composite material). In such uses, the roving assembly 120 is unwound at a relatively high speed to provide glass fiber for subsequent manufacturing processes.
[0009] like Figure 3 As seen in , in a continuous manufacturing process, multiple roving assemblies are typically operatively connected in series. Figure 3 The first roving assembly 202 is shown operatively connected to the second roving assembly 204, such that when the first strand 206 (comprising the roving assembly) from the first roving assembly 202 has been completely unwound, the process continues with the second strand 208 from the second roving assembly 204, and so on. Specifically, the first strand 206 from the first roving assembly 202 has a first leading end 210 and a first trailing end 212, and the second strand 208 from the second roving assembly 204 has a second leading end 214 and a second trailing end 216. To operatively connect the first roving assembly 202 to the second roving assembly 204, the first trailing end 212 of the first strand 206 and the second leading end 214 of the second strand 208 are tied together to form a transfer knot 220. This process can be repeated for each discrete fiber strand on the roving assemblies 202, 204.
[0010] However, conventional transfer knots 220 may cause defects in the final product. For example, conventional transfer knots 220 include a solid block or ball of the glass fiber strands that form the knot. For example, one conventional transfer knot 220 commonly used has a block or ball with a thickness or diameter of approximately 3.35 mm. When chopped during the manufacturing process, such glass fiber blocks or balls may not be fully dispersed. Because the chopped glass fibers of the transfer knot 220 are not reliably dispersed (i.e., some fibers remain clumped), the final product (e.g., a fiberglass body panel) (which generally requires a smooth, consistent finish) may have lumps (or other non-smooth finishes) and / or discoloration caused by the transfer knot. Summary of the Invention
[0011] Various aspects of the present inventive concepts relate to roving assemblies, and more particularly to methods and fastening arrangements for operatively connecting fiber strands of a first roving assembly to fiber strands of a second roving assembly.
[0012] In some examples, a pair of roving assemblies are connected by a first connecting portion. The first roving assembly has one or more strands of continuous first glass fiber, the one or more strands having a first main strand, the first main strand having a first front end portion and a first tail end portion opposite the first front end portion. The second roving assembly has one or more strands of continuous second glass fiber, the one or more strands having a second main strand, the second main strand having a second front end portion and a second tail end portion opposite the first front end portion. The first connecting portion connects the first tail end portion to the second front end portion. The first connecting portion includes a first strand of the first main strand and a second strand of the first main strand, the first strand forming a first spiral wrap around the second front end portion of the second roving assembly, and the second strand forming a second spiral wrap around the second front end portion of the second roving assembly.
[0013] In some examples, a method of connecting a first roving assembly to a second roving assembly includes separating a first end of a first main strand of the first roving assembly into a first strand, a second strand, and a third strand. The first strand is helically wound around a second leading end portion of a second main strand of the second roving assembly to form a first helical winding. The second strand is helically wound around the second leading end portion to form a second helical winding. The first helical winding and the second helical winding are positioned at a first end of the first roving assembly to form a first connection. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The features and advantages of the present invention will become apparent to those skilled in the art to which the present invention pertains by reading the following description in conjunction with the accompanying drawings.
[0015] Figure 1 Schematic diagram of a conventional system for winding a plurality of strands (particularly glass fiber strands) into a cake or the like.
[0016] Figure 2 Is to use from Figure 1 Schematic diagram of a conventional process for winding a roving assembly from a plurality of fiber strands drawn from a plurality of cakes of the type shown in FIG.
[0017] Figure 3 is a schematic diagram of a conventional method of connecting two roving assemblies in series.
[0018] Figure 4 is a schematic diagram of a first roving assembly and a second roving assembly.
[0019] Figures 5 to 11 According to the present invention, Figure 4 Schematic diagram of an exemplary method of connecting roving assemblies in series and a fastening configuration. DETAILED DESCRIPTION
[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by those skilled in the art to which these exemplary embodiments belong. The terms used in the description herein are only used to describe the exemplary embodiments and are not intended to limit the exemplary embodiments. Therefore, the overall inventive concept is not intended to be limited to the specific embodiments shown herein. Although other methods and materials similar or equivalent to those described herein can be used in the implementation or testing of the present invention, preferred methods and materials are described herein.
[0021] 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.
[0022] Unless otherwise indicated, all numbers used in the specification and claims expressing amounts of ingredients, chemical and molecular properties, reaction conditions, and the like, as well as physical and measured properties, should be understood as being modified in all instances by the term "about". Therefore, unless otherwise indicated, the numerical parameters set forth in the specification and the appended claims are approximate and may vary depending upon the desired properties sought to be obtained by the exemplary embodiments herein. At the very least, each numerical parameter should be interpreted in light of the number of significant figures and ordinary rounding techniques.
[0023] Unless otherwise indicated, any element, property, feature, or combination of elements, properties, and features may be used in any embodiment disclosed herein, regardless of whether the element, property, feature, or combination of elements, properties, and features is explicitly disclosed in that embodiment. It should be readily understood that features described with respect to any aspect described herein may be applicable to other aspects described herein, so long as the features are compatible with that aspect. Specifically, features described herein in relation to the method may be applicable to the product, and vice versa.
[0024] Although the numerical ranges and parameters setting forth the broad scope of the exemplary embodiments are approximate, the numerical values set forth in the specific examples are reported as precisely as possible. However, any numerical value inherently contains certain errors inevitably resulting from the standard deviation found in their respective testing measurements. Every numerical range given throughout the specification and claims will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were expressly written herein.
[0025] The present disclosure is directed to joining fiber strands of a first roving package to fiber strands of a second roving package in a manner that allows for a continuous manufacturing process while avoiding or inhibiting the formation of defects resulting from the joining in a final product utilizing chopped fibers from the fiber strands.
[0026] Figures 4 to 11 An exemplary method and fastening arrangement for operably connecting a first roving assembly 302 to a second roving assembly 304 is shown. The first roving assembly 302 includes a wound first main strand 306, and the second roving assembly 304 includes a wound second main strand 308. The first main strand 306 is connected to the second main strand 308 such that once the first main strand 306 has been completely unwound, the second main strand 308 begins to unwind. It should be understood that this exemplary method / arrangement can be implemented for any number of discrete strands on the roving assemblies 302, 304. Furthermore, it should be understood that this exemplary method / arrangement can be used to connect more than just two roving assemblies in series. For example, this exemplary method / arrangement can be used to connect all roving assemblies in a pallet, package, or group together in series. Another exemplary method / arrangement may also be used to connect multiple roving assembly pallets, packages, or groups in series by connecting the last roving assembly in a first roving assembly pallet, package, or group to the last roving assembly in a second pallet, package, or group, and so on. Thus, this exemplary method / arrangement may be used to create a continuous supply of glass fiber strands for processing.
[0027] The first main strand 306 has a first leading end portion 310 and a first trailing end portion 312 opposite the first leading end portion 310. The entire length of the first main strand 306 extends from the first leading end portion 310 to the first trailing end portion 312. The second main strand 308 has a second leading end portion 314 and a second trailing end portion 316 opposite the second leading end portion 314. The entire length of the second main strand 308 extends from the second leading end portion 314 to the second trailing end portion 316. The first leading end portion 310 and the second leading end portion 314 are arranged to serve as a first portion of the main strand 306 unwound from the first roving assembly 302 and a first portion of the main strand 308 unwound from the second roving assembly 304, respectively. Figure 4 In the illustrated example, the first leading portion 310 and the second leading portion 314 are shown as extending from a first inner diameter 318 of the first roving assembly 302 and a second inner diameter 320 of the second roving assembly 304, respectively. Additionally, the first tail end portion 312 and the second tail end portion 316 are shown as extending from a first upper end 322 of the first roving assembly 302 and a second upper end 324 of the second roving assembly 304, respectively. However, in other examples, the roving assemblies 302, 304 may be wound and arranged such that the first leading portion 310 and the second leading portion 314 and the first tail end portion 312 and the second tail end portion 316 extend from other locations on the respective roving assemblies 302, 304.
[0028] In order to operatively connect the first roving assembly 302 to the second roving assembly 304, the first tail portion 312 of the first main strand 306 and the second leading portion 314 of the second main strand 308 are connected via the first connecting portion 326 ( Figure 11 )connect.
[0029] refer to Figure 5 , in order to operatively connect the first tail portion 312 to the second front portion 314 ( Figure 4 ), the first tail portion 312 is bundled or divided into two separate strands (i.e., fiber groups): secondary strand A and secondary strand B. In some examples, the number of fibers in secondary strand A is in the range of 80% to 120%, or 90% to 110%, of the number of fibers in secondary strand B (i.e., approximately evenly bundled). However, in other examples, secondary strand A may have less than 80% or more than 120% of the number of fibers in secondary strand B.
[0030] refer to Figure 6 After the first tail portion 312 is bundled into the secondary strands A and B, at least a portion of the secondary strands B is bundled or separated into two separate strands (i.e., fiber groups): secondary strands B1 and secondary strands B2. In some examples, the number of fibers in secondary strands B1 is in the range of 80% to 120%, or 90% to 110%, of the number of fibers in secondary strands B2 (i.e., the fibers are generally evenly bundled). However, in other examples, secondary strands B1 may have less than 80% or more than 120% of the number of fibers in secondary strands B2.
[0031] Thus, in some examples, sub-filament A includes more filaments from the first end portion 312 than each of sub-filaments B1 and B2. In some examples, for example, sub-filament A includes 40% to 60% of the total filaments of the first end portion 312, and sub-filaments B1 and B2 each include 10% to 30% of the total filaments of the first end portion 312. Thus, in some examples, sub-filament A includes approximately twice as many filaments as each of sub-filaments B1 and B2.
[0032] refer to Figure 7 , with the secondary filaments A and B1 extending generally in the same direction (e.g., parallel to each other, generally V-shaped, forming an angle of less than 60 degrees with each other, etc.), the second leading end portion 314 of the second roving assembly 304 is positioned to traverse and be in front of the secondary filament A, and traverse and be behind the secondary filament B1 (or vice versa). Thus, the secondary filaments A and B1 are positioned on opposite sides (i.e., front and back) of the second leading end portion 314. Figure 7 In the example shown in FIG. 3 , the second leading end portion 314 , the secondary filament A, and the secondary filament B1 form an H shape.
[0033] refer to Figure 8 , with the second front end portion 314 extending transversely to the sub-filament A and the sub-filament B1, the sub-filament A is wrapped once around the front of the second front end portion 314 and over the rear thereof to form a first spiral wrapping 330 of the sub-filament A around the second front end portion 314. The sub-filament A is wrapped inwardly (i.e., in a direction toward the sub-filament B1) around the second front end portion 314. Similarly, the sub-filament B1 is wrapped once around the rear of the second front end portion 314 and over the front thereof to form a second spiral wrapping 332 of the sub-filament B1 around the second front end portion 314. The sub-filament B1 is wrapped inwardly (i.e., in a direction toward the sub-filament A) around the second front end portion 314. Figure 8 In the example of , the secondary filament A (around the front and over the back) is spirally wound in the opposite direction to the secondary filament B1 (around the back and over the front). However, in other examples, the secondary filament A and the secondary filament B1 can be wound in the same direction. Figure 8 In the example shown, both the secondary filament A and the secondary filament B1 are wrapped once around the second leading end portion 314 (ie, a single helical wrap).
[0034] refer to Figure 9 Once the secondary filaments A and / or B1 have been helically wrapped around the second leading portion 314, the primary connection 326 is formed by moving the positions of the first helical wrap 330 and the second helical wrap 332 on the secondary filaments A and B1, respectively, to near or at the upper end 322 of the first roving assembly 302 and pulling the helical wraps tightly around the second leading portion 314. For example, the first helical wrap 330 and the second helical wrap 332 may be moved to the first trailing portion 312 ( Figure 5 ) is separated from the wound roving assembly 302, and the sub-filament B1 is separated from the sub-filament B2. Since the sub-filament A and the sub-filament B1 are wound around the second leading end portion 314, moving the first spiral winding 330 and the second spiral winding 332 to the upper end 322 of the first roving assembly 302 will also move the portion of the second leading end portion 314 wrapped by the first spiral winding 330 and the second spiral winding 332 to the upper end 322. The main connecting portion 326 has a width or diameter in the range of 1.8 mm to 2.6 mm, or 2.0 mm to 2.4 mm, or 2.1 mm to 2.2 mm when formed. In contrast, the width or diameter of each of the first tail end portion 312 and the second leading end portion 314 is in the range of about 1.1 mm to about 1.4 mm, or is about 1.25 mm, and the width of a conventional knot
[0035] like Figure 9As shown, once the first spiral winding 330 and the second spiral winding 332 are positioned at the upper end 322 of the first roving assembly 302, the second front end portion 314, the loose end portion 340 of each of the sub-filaments A, sub-filaments B1 and sub-filaments B2 extend from the upper end 322 of the first roving assembly 302 (i.e., from the main connection portion 326), and the transition portion 342 of the second front end portion 314 extends from the second roving assembly 304 to the main connection portion 326.
[0036] refer to Figure 10 , in order to fix the loose end portion 340 ( Figure 9 ), the loose end portions 340 are combined into a single combined strand 344. The single combined strand 344 is then wrapped around the transition portion 342 of the second leading end portion 314 to secure the end portion 346 of the single combined strand 344 to the transition portion 342. In the example shown, the single combined strand 344 is helically wrapped once around the transition portion 342 to form a loop 348, and is then tightened to form the secondary connection 350. However, in other examples, the single combined strand 344 can be wrapped around the transition portion 342 of the second leading end portion 314 to secure the end portion 346 of the single combined strand 344 to the transition portion 342 in any suitable manner.
[0037] refer to Figure 11 , when the first roving assembly 302 and the second roving assembly 304 are as described above with respect to Figures 4 to 10 When connected, the second leading end portion 314 of the second main filament 308 is connected to the first tail end portion 312 of the first main filament 306 by the main connecting portion 326. The main connecting portion 326 is configured to be substantially dispersed into separate chopped fibers when chopped (i.e., not retained in the fiber block). In this way, the main connecting portion essentially disappears during downstream processing (i.e., chopping / cutting of the fiber filaments). As a result, the main connecting portion 326 does not cause defects in the surface finish of the finished product produced by the chopped strands of the main connecting portion 326 or cause any significant visual discoloration or blemishes on the finished product (e.g., a glass fiber reinforced vehicle panel). In the example shown, the main connecting portion 326 is formed by a first spiral winding 330 and a second spiral winding 332.
[0038] In addition, the second leading end portion 314 and the loose end portion 340 of the first trailing end portion 312 are connected to the transition portion 342 of the second leading end portion 314 via a secondary connection 350. Like the primary connection 326, the secondary connection 350 is configured to substantially disperse into separate chopped fibers when chopped (i.e., not remain in a fiber mass). As a result, the secondary connection 350 does not cause defects in the surface finish of a finished product produced from the chopped strands of the secondary connection 350 or cause any noticeable visual discoloration or blemishes on the finished product (e.g., a glass fiber reinforced vehicle panel).
[0039] The disclosed exemplary methods and fastening configurations result in a loop 352 being formed between the primary connection 326 and the secondary connection 350 by the transition portion 342 and the combined strands 344. In some examples, the distance X between the primary connection 326 and the secondary connection 350 is in the range of 2.0 inches to 4.0 inches, or 2.2 inches to 3.8 inches, or 2.5 inches to 3.3 inches. However, in other examples, the distance X can be greater than 4.0 inches and less than 2.0 inches. In some examples, the distance Y between the secondary connection and the bottom end 354 of the first roving assembly 302 is in the range of 1.0 inches to 4.0 inches, 1.5 inches to 3.5 inches, or 2.0 inches to 3.0 inches. However, in other examples, the distance Y can be less than 1.0 inches and greater than 4.0 inches. In some examples, the total height of the first roving assembly 302 is in the range of 9.5 inches to 11.5 inches, or 10 inches to 11 inches, or 10.2r inches to 10.75 inches. All numerical ranges should be understood to include all possible incremental sub-ranges within the outer boundaries of the range. Thus, for example, a distance of 2.0 inches to 4.0 inches discloses, for example, 2.0 inches to 3 inches, 2.5 inches to 4.0 inches, 2.3 inches to 3.5 inches, etc.
[0040] The method and fastening configuration of the present invention for operably connecting two roving assemblies may have any combination or sub-combination of the disclosed characteristics and the range of those characteristics disclosed herein. Although the present invention has been illustrated by the description of the embodiments of the present invention, it is not the intention of the applicant to restrict or limit the scope of the appended claims to such details. For example, although the first connection portion is described as including a single spiral winding of the secondary filament A and a single spiral winding of the secondary filament B1, in some embodiments, the secondary filament A and / or the secondary filament B can be spirally wound multiple times around the second leading end portion, as long as the first connection portion is substantially dispersed into separate chopped fibers when chopped. Additional advantages and modifications will be apparent to those skilled in the art. Therefore, the present invention in its broader aspects is not limited to the specific details, representative devices or illustrative examples shown and described. Therefore, deviations from such details may be made without departing from the spirit or scope of the general inventive concept.
Claims
1. A pair of connected roving assemblies, the pair of connected roving assemblies comprising: a first roving assembly comprising a first main strand of continuous first glass fiber, the first main strand having a first leading end portion and a first trailing end portion opposite the first leading end portion; a second roving assembly comprising a second main strand of continuous second glass fiber, the second main strand having a second leading end portion and a second trailing end portion opposite the first leading end portion; and A first connecting portion, the first connecting portion connecting the first tail end portion to the second front end portion, the first connecting portion comprising: a first plurality of strands of the first main strand, the first plurality of strands forming a first helical wrap around the second leading end portion of the second roving assembly; and A second strand of the first main strand forms a second helical wrap around the second leading end portion of the second roving assembly.
2. A pair of connected roving assemblies according to claim 1, wherein: The first helical winding is wound opposite the second helical winding.
3. A pair of connected roving assemblies according to claim 1, wherein: The first helical wrap is positioned adjacent to the second helical wrap at a first end of the first roving assembly.
4. A pair of connected roving assemblies according to claim 3, further comprising a tertiary strand of the first main strand, the tertiary strand not being wound around the second leading end portion at the first end of the first roving assembly.
5. A pair of connected roving assemblies according to claim 1, wherein: The first connection is positioned at a first end of the first roving package, and the second connection is positioned along a side of the first roving package at approximately 40% to 60% of the total height of the first roving package.
6. The pair of connected roving assemblies according to claim 1, further comprising a second connecting portion, wherein: The second connecting portion includes a combined strand, the combined strand including the first strand, the second strand, the second front end of the second main strand, and a loose end portion of the third strand of the first main strand, wherein the combined strand forms a third spiral wrap around the second front end portion at a position on the second front end portion between the first connecting portion and the second roving assembly.
7. A pair of connected roving assemblies according to claim 6, wherein: The first strand includes a greater number of glass fiber strands than the third strand.
8. A pair of connected roving assemblies according to claim 1, wherein: The first strand includes a greater number of glass fiber strands than the second strand.
9. A pair of connected roving assemblies according to claim 1, wherein: The total number of glass fiber strands in the first main strand is a first strand number, and the first primary strand accounts for 40% to 60% of the first strand number.
10. A pair of connected roving assemblies according to claim 9, wherein: The second raw yarn accounts for 10% to 30% of the first raw yarn.
11. A method of connecting a first roving package to a second roving package, wherein: The first roving assembly includes a first main strand of a continuous first glass fiber, the first main strand having a first leading end portion and a first tail end portion opposite the first leading end portion, and the second roving assembly includes a second main strand of a continuous second glass fiber, the second main strand having a second leading end portion and a second tail end portion opposite the first leading end portion, the method comprising: separating the first tail end into a first protofilament, a second protofilament, and a third protofilament; helically wrapping the first strand around the second leading end portion to form a first helical wrap; helically wrapping the second strand around the second leading end portion to form a second helical wrap; and The first helical wrap and the second helical wrap are positioned at a first end of the first roving package to form a first connection.
12. The method according to claim 11, wherein Helically wrapping the first strand around the second leading end portion is in a first direction, and helically wrapping the second strand around the second leading end portion is in a second direction opposite to the first direction.
13. The method according to claim 11, further comprising: combining the first raw yarn, the second raw yarn, the second front end portion, and the third raw yarn into a combined raw yarn; as well as The combined strand is helically wrapped around the second leading end portion at a location between the first location and the second roving assembly to form a second connection.
14. The method according to claim 11, wherein The first strand includes a greater number of glass fiber strands than the second strand.
15. The method according to claim 1, wherein The first strand includes a greater number of glass fiber strands than the third strand.
16. The method according to claim 1, wherein The total number of glass fiber strands in the first main strand is a first strand number, and the first primary strand accounts for 40% to 60% of the first strand number.
17. The method according to claim 16, wherein The second raw yarn accounts for 10% to 30% of the first raw yarn.