Device for changing advancement direction and device for producing glass fibers

Abstract

A device 5 for changing an advancement direction comprises: a roller part 7 that rotates so as to change the advancement direction of a strand ST which is constituted by glass fibers GF; and a support part 8 that supports the roller part 7. The roller part 7 is provided with an outer peripheral surface 10 and a plurality of protrusions 11 that protrude from the outer peripheral surface 10 and contact the strand ST. The protrusions 11 extend along the axial direction of the roller part 7.

Description

Device for Changing the Travel Direction and Glass Fiber Manufacturing Apparatus

[0001] The present invention relates to a device for changing the travel direction of a glass strand composed of glass fibers and a glass fiber manufacturing apparatus.

[0002] As is well known, glass strands are widely used as reinforcing materials for GRC (Glass Fiber Reinforced Concrete) and are known as an effective means to compensate for brittleness in cement and improve tensile strength, flexural strength, and impact strength.

[0003] As a method for manufacturing GRC, for example, a method is known in which glass chopped strands (hereinafter simply referred to as "chopped strands") obtained by cutting glass strands (hereinafter simply referred to as "strands") into a mortar composed of pre-mixed cement, aggregate, water, admixtures, etc. are mixed and then formed into a predetermined shape.

[0004] Strands can be obtained by applying a sizing agent to glass fibers obtained by drawing molten glass from a bushing having hundreds to thousands of nozzles using an applicator and then gathering them by a gathering shoe. The obtained strands are cut to a predetermined length and used as chopped strands.

[0005] Patent Document 1 discloses a method for manufacturing chopped strands using the direct method. In this manufacturing method, chopped strands are manufactured by directly cutting the strands by a cutting roller while conveying the strands formed by a gathering shoe (converging roller) in a predetermined direction by a guide roller and a feed roller (see the upper left column of the third page and FIG. 1 of the same document).

[0006] The guide roller functions as a travel direction changing device that changes the travel direction of the strand from the vertical direction to the direction toward the guide roller at a position below the gathering shoe.

[0007] Japanese Patent Application Laid-Open No. 4-164838

[0008] In methods such as the one disclosed in Patent Document 1, where strands are transported by guide rollers, the strands sometimes become entangled in the guide rollers. When such entanglement occurs, the strands are cut before reaching the feed rollers, interrupting the production of chopped strands. Therefore, it was necessary to periodically replace the guide rollers to prevent strand entanglement.

[0009] If the guide rollers are replaced frequently, the manufacturing efficiency of chopped strands decreases, so it is necessary to reduce the frequency of strands wrapping around the guide rollers.

[0010] This invention has been made in view of the above circumstances, and its technical objective is to suppress the occurrence of strand entanglement with the direction-changing device.

[0011] (1) The present invention is for solving the above problems and is a device for changing the direction of travel of a strand made of glass fibers, comprising a roller portion that rotates to change the direction of travel of the strand, and a support portion that supports the roller portion, wherein the roller portion comprises an outer peripheral surface and a plurality of protrusions that protrude from the outer peripheral surface and contact the strand, and the protrusions are configured to extend along the axial direction of the roller portion.

[0012] With this configuration, multiple protrusions are formed on the outer surface of the roller portion, and the strand is supported by these protrusions, thereby minimizing the contact area of ​​the strand with the roller portion.

[0013] A sizing agent is applied to the strand, and when the sizing agent adheres to the roller and hardens (gums up), the strand becomes difficult to detach from the roller, causing it to wrap around the roller. In this invention, the contact area of ​​the strand with the roller is made smaller than in conventional methods, thereby reducing the amount of sizing agent that adheres to the contact area. This effectively suppresses the occurrence of strand wrapping around the roller.

[0014] Furthermore, since the protrusions are configured to extend in the axial direction of the roller, it is possible to change the direction of travel of multiple strands simultaneously. However, if multiple island-shaped protrusions are formed, strands tend to get stuck in the gaps between adjacent protrusions. In that case, there is a risk of problems such as the sizing agent easily adhering to the roller, or strands getting caught on the protrusions and cutting, or becoming entangled with the roller. Therefore, it is preferable that the protrusions are configured to extend in the axial direction of the roller.

[0015] (2) In the direction-changing device described in (1) above, the outer circumferential surface may be circular in shape, and the convex portion may have an arc-shaped contour in a cross-section in a direction perpendicular to the axial direction of the roller portion.

[0016] With this configuration, the convex portion having an arc-shaped contour easily achieves a suitable contact area with the strand, enabling appropriate contact and separation from the strand. This effectively suppresses the strand from wrapping around the roller portion. Furthermore, since the convex portion having an arc-shaped contour has a structure that is less likely to damage the strand, it is possible to prevent the glass fibers contained in the strand from being cut by the convex portion.

[0017] (3) In the device for changing the direction of travel described in (2) above, when the radius of the outer surface of the roller portion in the cross-section is R and the height of the protrusion is H, the value of the ratio H / R may be 0.05 or more and 0.07 or less.

[0018] With this configuration, by defining the height of the protrusion to be within the above range, the wrapping of the strand around the roller can be effectively suppressed.

[0019] (4) In the direction-changing device described in (2) above, when the radius of the outer surface relating to the roller portion in the cross-section is R and the arc length in the region where one of the protrusions is formed on the outer surface is L, the value of the ratio L / R may be 0.05 or more and 0.15 or less.

[0020] With this configuration, by defining the size (arc length L) of the circumferential protrusion on the outer surface of the roller portion to be within the above range, the strand wrapping around the roller portion can be effectively suppressed.

[0021] (5) In the device for changing the direction of travel described in (2) above, when the radius of the outer surface relating to the roller portion in the cross-section is R and the arc length in the region on the outer surface where the protrusion is not formed is W, the value of the ratio W / R may be 0.002 or more and 0.15 or less.

[0022] With this configuration, the arc length W corresponds to the size of the groove formed between the protrusions. The groove can contain the sizing agent adhering to the strand. By defining the arc length W to be within the above range, the amount of sizing agent adhering to the protrusions can be suitably reduced. This effectively suppresses the strand from wrapping around the roller.

[0023] (6) In the direction-changing device described in any of (1) to (5) above, the roller portion may be made of a thermosetting resin.

[0024] (7) The device for changing the direction of travel described in any of (1) to (6) above may further include a holder portion that holds at least one end of the support portion. With this configuration, the support portion can be reliably supported by the holder portion.

[0025] (8) In the direction-changing device described in (7) above, the holder portion may hold only one end of the support portion.

[0026] (9) The present invention is for solving the above problems and is characterized by comprising: a bushing for drawing out a plurality of glass fibers; an applicator for applying a sizing agent to the plurality of glass fibers; a gathering shoe for gathering the plurality of glass fibers to form a strand; a device for changing the direction of travel as described in any of (1) to (8) above; and a cutting device for cutting the strand.

[0027] With this configuration, by incorporating the direction-changing device according to the present invention, the glass fiber manufacturing apparatus can effectively suppress the occurrence of strand entanglement with the roller section.

[0028] According to the present invention, it is possible to suppress the occurrence of strand entanglement with the direction-changing device.

[0029] This is a side view showing a chopped strand manufacturing apparatus. This is a plan view of the direction-changing device along the line of arrow II-II in Figure 1. This is a cross-sectional view of the direction-changing device along the line of arrow III-III in Figure 2. This is an enlarged cross-sectional view of the roller section in the direction-changing device. This is a plan view showing another example of the direction-changing device.

[0030] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. Figures 1 to 5 show one embodiment of a chopped strand manufacturing apparatus including a direction-changing device according to the present invention.

[0031] The manufacturing equipment for chopped strands employs a so-called direct method. That is, the manufacturing equipment produces chopped strands by directly cutting strands, which are bundles of multiple glass fibers, without winding them up.

[0032] As shown in Figure 1, the manufacturing apparatus 1 comprises a bushing 2, an applicator 3, a gathering shoe 4, a direction-changing device 5, and a cutting device 6.

[0033] The bushing 2 is for forming glass fibers GF from molten glass supplied from a feeder (not shown). The bushing 2 has a plurality of nozzles (not shown) for forming the glass fibers GF. The plurality of nozzles are regularly arranged along the longitudinal and transverse directions at the bottom of the bushing 2.

[0034] Applicator 3 is for applying the sizing agent to the glass fibers GF. Applicator 3 is configured as a roller that applies the sizing agent to multiple glass fibers GF descending from the nozzle of bushing 2. The sizing agent includes a coupling agent, as well as a binding agent, lubricant, antistatic agent, defoamer, etc.

[0035] The gathering shoe 4 is positioned below the applicator 3. The gathering shoe 4 is for converging multiple glass fibers GF supplied by the bushing 2 to form a strand ST. In this embodiment, multiple gathering shoes 4 are arranged at intervals, allowing multiple strand STs to be formed from the glass fibers GF.

[0036] The direction-changing device 5 is located below the gathering shoe 4. The direction-changing device 5 is for changing the transport direction of the strand ST formed by the gathering shoe 4. The direction-changing device 5 guides the strand ST, which is transported vertically, to the lateral direction.

[0037] As shown in Figure 2, the direction-changing device 5 comprises a roller section 7, a support section 8, and a holder section 9.

[0038] The roller section 7 contacts multiple strands ST and changes the direction of travel of each strand ST. The multiple strands ST are in contact with the roller section 7 at regular intervals in the axial direction X of the roller section 7. The roller section 7 is made of a thermosetting resin such as bakelite, but is not limited to this and may be made of metal or other materials.

[0039] The roller portion 7 comprises an outer circumferential surface 10 and a plurality of protrusions 11 that protrude from the outer circumferential surface 10 and contact the strand ST.

[0040] The outer circumferential surface 10 is configured in a circular shape, and its diameter is preferably 50 mm or more and 300 mm or less.

[0041] As shown in Figure 2, the protrusion 11 is a linear portion extending along the axial direction X of the roller portion 7. The protrusion 11 is formed along the entire length of the roller portion 7 from one end to the other in the axial direction X. However, the length of the protrusion 11 in the axial direction X may be shorter than the total length of the roller portion 7.

[0042] As shown in FIG. 3, the plurality of convex portions 11 are formed at regular intervals D in the circumferential direction of the outer peripheral surface 10. The interval (pitch) D between the convex portions 11 is preferably 5 mm or more and 50 mm or less. If the pitch D is within the above range, the convex portions 11 can make suitable contact with and separation from the strand ST. Thereby, the winding of the strand ST around the roller portion can be effectively suppressed.

[0043] The convex portion 11 has an arc-shaped contour 11a in a cross section when the roller portion 7 is cut along a direction (radial direction) Y perpendicular to the axial direction X of the roller portion 7 (see FIGS. 3 and 4). The radius of curvature of the contour 11a is preferably 2 mm or more and 10 mm or less. The contour 11a is configured to be semi-circular in a cross-sectional view, but is not limited to this configuration.

[0044] A groove portion 12 having the outer peripheral surface 10 as the bottom surface is formed between two adjacent convex portions 11 in the circumferential direction of the roller portion 7.

[0045] In the cross section shown in FIG. 3 or FIG. 4, when the radius of the outer peripheral surface 10 related to the roller portion 7 is R and the height of the convex portion 11 is H, the value of the ratio H / R is preferably 0.05 or more and 0.07 or less. The height H of the convex portion 11 is the distance from the outer peripheral surface 10 to the top of the convex portion 11 in the radial direction Y of the roller portion 7. The height H of the convex portion is preferably 4 mm or more and 20 mm or less.

[0046] As shown in FIG. 4, when the arc length in the region 10a where one convex portion 11 is formed on the outer peripheral surface 10 is L, the value of the ratio L / R is preferably 0.05 or more and 0.15 or less. The arc length L of this region 10a is preferably 1 mm or more and 50 mm or less. This region 10a is constituted by a virtual line (virtual arc) drawn so as to connect the region 10b where no convex portion 11 is formed on the outer peripheral surface 10. The arc length L of this region 10a corresponds to the width (circumferential width) of the base portion of the convex portion 11 in the circumferential direction of the outer peripheral surface 10.

[0047] As shown in Fig. 4, when the arc length in the region 10b where the convex portion 11 is not formed on the outer peripheral surface 10 is W, the value of the ratio W / R is preferably 0.002 or more and 0.15 or less. This arc length W is preferably 0.1 mm or more and 15 mm or less. This arc length W corresponds to the width (groove width) in the circumferential direction of the outer peripheral surface 10 as the bottom surface of the groove portion 12.

[0048] The support portion 8 is configured as a shaft portion that supports the roller portion 7. The support portion 8 is configured to penetrate the central portion of the roller portion 7 in the axial direction X. One end portion of the support portion 8 protrudes from one end portion of the roller portion 7 in the axial direction X, and the other end portion of the support portion 8 protrudes from the other end portion of the roller portion 7 in the axial direction X. The support portion 8 is integrally fixed to the roller portion 7 and is configured to rotate together with the roller portion 7. In this embodiment, one end portion of the support portion 8 is configured to protrude from one end portion of the roller portion 7 in the axial direction X, but is not limited to this configuration, and may be configured not to protrude from one end portion of the roller portion 7 in the axial direction X.

[0049] The holder portion 9 holds only one end portion of the support portion 8. In this way, the roller portion 7 can be detached from the other end portion of the support portion 8, so that the replacement work of the roller portion 7 becomes easy. The holder portion 9 includes a bearing portion that rotatably supports the end portion of the support portion 8. The holder portion 9 is configured to be movable in the vertical direction by a lifting mechanism (not shown). The support portion 8 held by the holder portion 9 is configured to rotate freely without being rotationally driven by a driving device.

[0050] As shown in Fig. 1, the cutting device 6 includes a cutting roller 13 that cuts the strand ST, a guide roller 14 that guides the strand ST to the cutting roller 13, and a pressing roller 15 that guides the strand ST to the cutting roller 13 together with the guide roller 14.

[0051] The cutting roller 13 has a plurality of cutting blades 16 on its outer peripheral portion. The cutting blades 16 are arranged at regular intervals in the circumferential direction on the outer peripheral portion of the cutting roller 13.

[0052] The guide roller 14 is positioned adjacent to the cutting roller 13. A layer of resin, such as urethane resin, is formed on the outer circumferential surface of the guide roller 14. The diameter of the guide roller 14 is larger than the diameter of the press roller 15. The guide roller 14 is configured to rotate around its central axis. The guide roller 14 is rotationally driven by a drive device (not shown).

[0053] The retaining roller 15, together with the guide roller 14, holds the strand ST in place and feeds the strand ST toward the cutting roller 13. The retaining roller 15 is located above the cutting roller 13. The retaining roller 15 is configured to rotate together with the guide roller 14 without being rotated by a drive device. However, the retaining roller 15 may be rotated by a drive device.

[0054] The following describes a method for manufacturing chopped strands using the manufacturing apparatus 1 with the above configuration.

[0055] In this method, first, multiple glass fibers GF are simultaneously formed by extruding molten glass downward from the nozzle of the bushing 2 (forming step). Each glass fiber GF drawn out from the nozzle moves downward from the bushing 2 and comes into contact with the applicator 3. The applicator 3 rotates and uniformly applies a sizing agent to all of the glass fibers GF (coating step).

[0056] The glass fibers GF coated with the sizing agent move downward and come into contact with the gathering shoe 4. Each of the multiple gathering shoes 4 forms a single strand ST by gathering multiple glass fibers GF (gathering process). The gathering shoe 4 guides the strand ST downward.

[0057] Subsequently, the strand ST comes into contact with the roller section 7 of the direction-changing device 5. The direction-changing device 5 applies a predetermined tension to the strand ST and changes the direction of the strand ST from vertical to horizontal (direction-changing process). As a result, the strand ST is transported to the cutting device 6 located to the side of the direction-changing device 5.

[0058] The cutting device 6 feeds the strand ST to the cutting roller 13 while it is sandwiched between the guide roller 14 and the pressing roller 15. In other words, the guide roller 14 and the pressing roller 15 function as devices that pull the strand ST along the transport path of the strand ST from the gathering shoe 4 to the cutting device 6.

[0059] The cutting roller 13 cuts the strand ST by sandwiching it between the cutting blade 16 and the guide roller 14 (cutting process). This forms a chopped strand CST of a predetermined length.

[0060] According to the chopped strand CST (glass fiber GF) manufacturing apparatus 1 of this embodiment described above, a plurality of protrusions 11 are formed on the outer circumferential surface 10 of the roller portion 7 of the direction of travel changing device 5, and these protrusions 11 are brought into contact with the strand ST, thereby making the contact area of ​​the strand ST with the roller portion 7 as small as possible.

[0061] During the bundling process, a bundling agent is applied to the strand ST, causing the bundling agent to adhere to the roller section 7. This makes it difficult for the strand ST to detach from the roller section 7, leading to the strand ST becoming entangled.

[0062] In this embodiment, by reducing the contact area of ​​the strand ST with the roller portion 7 compared to conventional methods, the amount of sizing agent adhering to the contact portion can be reduced. This effectively suppresses the occurrence of the strand ST wrapping around the roller portion 7.

[0063] In this embodiment, by setting the protrusions 11 to a predetermined height H and forming grooves 12 between two adjacent protrusions 11, the sizing agent adhering to the strand ST can be contained in the grooves 12. This makes it possible to suppress the occurrence of strand ST entanglement caused by the sizing agent remaining attached to the protrusions 11.

[0064] In particular, in the direct method, the distance between the bushing 2 and the direction-changing device 5 is short, and the relatively high-temperature strand ST comes into contact with the roller section 7, making it easy for the sizing agent to gummy up on the surface of the roller section 7. Therefore, it is easy to enjoy the benefits of adopting the structure of the roller section 7 in this embodiment.

[0065] Furthermore, the present invention is not limited to the configuration of the above embodiments, nor is it limited to the effects described above. The present invention can be modified in various ways without departing from the spirit of the invention.

[0066] In the above embodiment, a direction-changing device 5 having a holder portion 9 that holds only one end of the support portion 8 was shown, but the present invention is not limited to this configuration. For example, as shown in Figure 5, the direction-changing device 5 may include a first holder portion 9a that holds one end of the support portion 8 and a second holder portion 9b that holds the other end of the support portion 8. In other words, in the present invention, the holder portion 9 (9a, 9b) only needs to hold at least one end of the support portion 8.

[0067] 1. Chopped strand manufacturing apparatus 2. Bushing 3. Applicator 4. Gathering shoe 5. Direction change device 6. Cutting device 7. Roller section 8. Support section 9. Holder section 10. Outer surface of the roller section 10a. Region on the outer surface of the roller section where a protrusion is formed 10b. Region on the outer surface of the roller section where a protrusion is not formed 11. Protrusion of the roller section 11a. Arc-shaped contour GF: Glass fiber ST: Strand

Claims

1. A device for changing the direction of travel of a strand made of glass fibers, comprising a roller section that rotates to change the direction of travel of the strand, and a support section that supports the roller section, wherein the roller section comprises an outer circumferential surface and a plurality of protrusions that protrude from the outer circumferential surface and contact the strand, and the protrusions are configured to extend along the axial direction of the roller section.

2. The device for changing the direction of travel according to claim 1, wherein the outer circumferential surface is configured in a circular shape, and the convex portion has an arc-shaped contour in a cross-section in a direction perpendicular to the axial direction of the roller portion.

3. The device for changing the direction of travel according to claim 2, wherein, in the cross-section, when the radius of the outer surface relating to the roller portion is R and the height of the protrusion is H, the value of the ratio H / R is 0.05 or more and 0.07 or less.

4. The device for changing the direction of travel according to claim 2, wherein, in the cross-section, when R is the radius of the outer circumferential surface relating to the roller portion and L is the arc length in the region where one of the protrusions is formed on the outer circumferential surface, the value of the ratio L / R is 0.05 or more and 0.15 or less.

5. The device for changing the direction of travel according to claim 2, wherein, in the cross-section, when the radius of the outer circumferential surface relating to the roller portion is R and the arc length in the region on the outer circumferential surface where the convex portion is not formed is W, the value of the ratio W / R is 0.002 or more and 0.15 or less.

6. The glass strand direction changing device according to any one of claims 1 to 5, wherein the roller portion is made of a thermosetting resin.

7. The device for changing the direction of travel according to any one of claims 1 to 5, further comprising a holder portion for holding at least one end of the support portion.

8. The device for changing the direction of travel according to claim 7, wherein the holder portion holds only one end of the support portion.

9. A glass fiber manufacturing apparatus comprising: a bushing for drawing out a plurality of glass fibers; an applicator for applying a sizing agent to the plurality of glass fibers; a gathering shoe for gathering the plurality of glass fibers to form a strand; a device for changing the direction of travel according to any one of claims 1 to 5; and a cutting device for cutting the strand.

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