Method and apparatus for manufacturing glass fiber

Abstract

To provide a method and an apparatus for manufacturing a glass fiber, capable of improving accuracy of temperature control.SOLUTION: An apparatus for manufacturing a glass fiber 11 includes: a moisture content measurement part 21 of measuring a moisture content included in a cake 30; a weight measurement part 22 for measuring weight of the cake 30; and a temperature control part 23 for controlling a temperature of molten glass in a bushing 12 on the basis of the moisture content and the weight of the cake 30. A method for manufacturing the glass fiber comprises: a winding step of forming the cylindrical cake 30; a moisture content measurement step of measuring the moisture content included in the cake 30 formed in the winding step; and a weight measurement step of measuring the weight of the cake 30 formed in the winding step. A temperature control part 23 controls the temperature of the molten glass in the bushing 12 in a subsequent winding step on the basis of the moisture content measured in the moisture content measurement step and the weight of the cake 30 measured in the weight measurement step.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method and an apparatus for producing glass fibers. [Background technology]

[0002] As shown in Patent Document 1, in the method for producing glass fibers, a plurality of glass filaments flowing out of a bushing are gathered by a gathering shoe to form a glass strand. The glass strand is then wound while being intertwined around a collet to produce a cake, which is a mass of the glass strand wound into a cylindrical shape.

[0003] In the above-mentioned manufacturing method, the weight of the cake is measured after the cake is formed. The weight of the cake varies depending on the fiber diameter of the glass filaments forming the cake. In the above-mentioned manufacturing method, the temperature of the molten glass in the bushing during subsequent cake formation is controlled based on the weight of the formed cake. For example, when the weight of the formed cake is greater than a reference value, the temperature of the molten glass in the bushing is reduced. When the temperature of the molten glass in the bushing is reduced, the outflow speed of the glass filaments flowing out of the bushing is reduced, and the fiber diameter of the glass filaments is reduced. As a result, it is possible to keep the weight of the cakes formed thereafter within the reference range. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-137222 A Summary of the Invention [Problem to be solved by the invention]

[0005] In the above-mentioned method for producing glass fibers, if moisture is attached to the surface of the glass filaments, the cake formed by winding the glass filaments will contain moisture. Therefore, it becomes difficult to accurately measure the weight of the formed cake itself. As a result, there is a risk that the above-mentioned temperature control of the molten glass will be adversely affected.

[0006] An object of the present invention is to provide a glass fiber manufacturing method and a glass fiber manufacturing apparatus that enable improvement in the accuracy of temperature control. [Means for solving the problem]

[0007] [1] A method for manufacturing glass fibers that solves the above problems is a method for manufacturing glass fibers that includes a winding step of forming a cylindrical cake by winding a glass strand formed from molten glass flowing out of a bushing onto a collet, and includes a moisture amount measuring step of measuring the moisture amount contained in the cake formed in the winding step, and a weight measuring step of measuring the weight of the cake formed in the winding step, and controls the temperature of the molten glass in the bushing in the subsequent winding step based on the moisture amount measured in the moisture amount measuring step and the weight of the cake measured in the weight measuring step.

[0008] According to this manufacturing method, the cake weight can be calculated accurately based on the moisture content of the cake. This enables appropriate temperature control based on the accurate cake weight. This reduces the occurrence of defective products, which contributes to improving the yield.

[0009] [2] In the moisture content measuring step in [1] above, the moisture content may be measured by passing an electric current through the cake. According to this manufacturing method, the moisture content of the cake can be suitably measured by measuring the moisture content using an electric current.

[0010] [3] In the moisture content measuring step in the above [1] or [2], a moisture content measuring point may be set on an axial end surface of the cake. The moisture content in the cake tends to be greater on the outer periphery due to the centrifugal force generated during winding, so by measuring the moisture content on the axial end surface of the cake, it is possible to measure the moisture content more accurately than by measuring the moisture content on the outer periphery of the cake.

[0011] [4] In the above [3], the measurement points on the axial end surface of the cake may be set at multiple locations different from each other in the radial direction. According to this manufacturing method, the moisture content is measured at a plurality of measurement points at different radial positions on the axial end face of the cake, making it possible to measure the moisture content with greater accuracy.

[0012] [5] In any one of the above [1] to [4], the moisture content measuring step may be performed when the cake is removed from the collet after the winding step.

[0013] According to this manufacturing method, it is possible to measure the moisture content of the cake at the same time as removing the cake from the collet, thereby improving productivity. [6] A glass fiber manufacturing apparatus that solves the above-mentioned problems is provided, which includes a bushing through which molten glass flows out, and a collet that forms a cylindrical cake by winding up a glass strand formed from the molten glass flowing out of the bushing, and further includes a moisture amount measuring unit that measures the amount of moisture contained in the cake, a weight measuring unit that measures the weight of the cake, and a temperature control unit that controls the temperature of the molten glass in the bushing based on the moisture amount and the weight of the cake.

[0014] According to this configuration, the cake weight can be calculated accurately based on the moisture content of the cake. This enables appropriate temperature control based on the accurate cake weight. This reduces the occurrence of defective products, which contributes to improving the yield.

[0015] [7] In the above item [6], the glass fiber manufacturing apparatus may include an extrusion section for extruding the cake from the collet, and the moisture content measuring section may be provided in the extrusion section.

[0016] According to this configuration, it is possible to measure the moisture content of the cake at the same time as removing the cake from the collet, thereby improving productivity. Effect of the Invention

[0017] According to the present invention, it is possible to improve the accuracy of temperature control. [Brief description of the drawings]

[0018] [Figure 1] FIG. 1 is a schematic side view showing a glass fiber manufacturing apparatus according to an embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view showing a part of the glass fiber manufacturing apparatus of the same configuration. [Diagram 3] FIG. 3 is a schematic cross-sectional view for explaining the method for producing glass fibers of the same embodiment. [Figure 4] FIG. 4 is a schematic side view showing a part of the glass fiber manufacturing apparatus of the same configuration. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, an embodiment of a glass fiber manufacturing method and a glass fiber manufacturing apparatus will be described with reference to the drawings. Note that in the drawings, for convenience of explanation, some of the configurations may be shown exaggerated or simplified. Furthermore, the dimensional ratios of each part may differ from the actual ones.

[0020] (Overall configuration of glass fiber manufacturing apparatus 11) 1, the glass fiber manufacturing apparatus 11 includes a bushing 12, an applicator 13, a gathering shoe 14, a cradle 15, a collet 16, and an extrusion unit 17. The glass fiber manufacturing apparatus 11 also includes a moisture content measuring unit 21, a weight measuring unit 22, and a temperature control unit 23.

[0021] The bushing 12 is a box-shaped container having a plurality of nozzles below, into which molten glass is supplied and from which a plurality of glass filaments F are pulled downward. Note that the drawings show the plurality of glass filaments F collectively and diagrammatically. In other words, the drawings show only the outermost portions of the plurality of glass filaments F, and show the range through which the glass filaments F pass.

[0022] The applicator 13 has a drive roller and is a device that applies a sizing agent to the glass filaments F. The gathering shoe 14 is a device that gathers and bundles a plurality of glass filaments F to which a sizing agent has been applied, to form a glass strand S. The glass filaments F and the glass strand S are composed of, for example, E glass (general-purpose alkali-free glass), A glass (alkali-resistant glass), C glass (acid-resistant alkali-lime-containing glass), D glass (low dielectric constant glass), S glass (high strength, high elasticity glass), T glass (high strength, high elasticity glass), H glass (high dielectric constant glass), etc.

[0023] In addition, a configuration may be adopted in which cooling water is sprayed onto the glass filaments F between the bushing 12 and the applicator 13. This allows the glass filaments F to be cooled to an appropriate temperature by the cooling water upstream of the applicator 13. Therefore, the sizing agent is favorably attached to the glass filaments F, and it is possible to suppress the generation of solids (gum-up) due to the progress of a chemical reaction of the sizing agent.

[0024] The cradle 15 includes a cradle body 15a and a traverse 15b provided on the cradle body 15a. The traverse 15b is provided on the cradle body 15a so as to be movable along the axis CL of the collet 16 in a direction intersecting the extension direction of the glass strand S. The traverse 15b reciprocates along the axis CL by the operation of a traverse drive device (not shown), thereby reciprocating the glass strand S along the axis CL.

[0025] (Colette 16) 1 and 2, the collet 16 includes a shaft-shaped collet body 16a and a cylindrical bobbin 16b arranged on the outer periphery of the collet body 16a. The bobbin 16b is configured to be able to transition between a connected state and a non-connected state with respect to the collet body 16a. In the connected state, the bobbin 16b can rotate integrally with the collet body 16a. On the other hand, in the non-connected state, the bobbin 16b can be removed from the collet body 16a in the direction of the axis CL.

[0026] The collet 16, with the bobbin 16b connected to the collet body 16a, rotates about the axis CL by the operation of a collet drive device (not shown), and winds the glass strand S that has passed through the traverse 15b onto the outer circumferential surface of the bobbin 16b. The glass strand S is wound onto the bobbin 16b of the collet 16 while being intertwined, to form a cake 30.

[0027] (Extrusion section 17) The pushing-out portion 17 is a member for pushing out the cake 30 from the collet 16. As shown in Fig. 2, the pushing-out portion 17 is extrapolated to the collet body 16a. The pushing-out portion 17 has a contact portion 17a that can contact the bobbin 16b in the axis CL direction, and an opposing portion 17b that faces the axial end face 30a of the cake 30 in the axis CL direction. The axial end face 30a of the cake 30 is one of both end faces of the cake 30 in the axis CL direction.

[0028] The push-out portion 17 is configured to be movable in the direction of the axis CL while being inserted into the collet body 16a. As shown in Fig. 3, the push-out portion 17 can move in the direction of the axis CL toward the bobbin 16b and the cake 30, thereby pushing out the bobbin 16b in the unconnected state from the collet body 16a by the contact portion 17a.

[0029] (Moisture content measuring unit 21) The moisture amount measuring unit 21 measures the amount of moisture contained in the formed cake 30. The moisture amount measuring unit 21 is, for example, a contact type moisture meter that uses electricity to measure the amount of moisture contained in an object. As the moisture amount measuring unit 21, for example, an electric resistance type moisture meter can be used.

[0030] 2, the moisture content measuring section 21 includes, for example, a plurality of outer circumference electrodes 21a and a plurality of inner circumference electrodes 21b. The outer circumference electrodes 21a and the inner circumference electrodes 21b are provided at the opposing portion 17b of the push-out section 17. The outer circumference electrodes 21a and the inner circumference electrodes 21b are provided so as to protrude toward the cake 30 in the direction of the axis CL.

[0031] As shown in FIG. 4, the outer circumference electrodes 21a are arranged on a concentric circle centered on the axis line CL. The outer circumference electrodes 21a are arranged, for example, four at 90° intervals in the circumferential direction centered on the axis line CL. The inner circumference electrodes 21b are arranged on a concentric circle centered on the axis line CL. The inner circumference electrodes 21b are arranged on the inner side of the outer circumference electrodes 21a. The inner circumference electrodes 21b are arranged, for example, four at 90° intervals in the circumferential direction centered on the axis line CL. The outer circumference electrodes 21a and the inner circumference electrodes 21b are arranged to be aligned along the radial direction centered on the axis line CL.

[0032] As shown in Fig. 3, in a state where the pushing-out portion 17 pushes out the bobbin 16b in the direction of the axis line CL, i.e., in a state where the contact portion 17a of the pushing-out portion 17 contacts the bobbin 16b, the tip of each of the electrodes 21a, 21b contacts the axial end face 30a of the cake 30. In this state, the moisture amount measuring unit 21 measures the moisture amount contained in the cake 30 by applying a voltage to the cake 30 from each of the electrodes 21a, 21b to pass a current therethrough. For example, the moisture amount measuring unit 21 may be configured to measure the moisture amount based on the electrical resistance when a current is passed through the cake 30. In addition, each of the electrodes 21a, 21b may be configured to elastically contact the cake 30 by a spring or the like, taking into account the effect on the cake 30.

[0033] As shown in FIG. 4, on the axial end surface 30a of the cake 30, a point where the outer periphery electrode 21a contacts is defined as a first measurement point M1, and a point where the inner periphery electrode 21b contacts is defined as a second measurement point M2.

[0034] The first measurement points M1 are set at positions corresponding to the arrangement of the outer periphery electrodes 21a. That is, the four first measurement points M1 corresponding to each of the outer periphery electrodes 21a are located on a concentric circle centered on the axis line CL. The four first measurement points M1 are set at intervals of, for example, 90° in the circumferential direction centered on the axis line CL.

[0035] The second measurement points M2 are set at positions according to the arrangement of the inner circumference side electrodes 21b. That is, the four second measurement points M2 corresponding to each of the inner circumference side electrodes 21b are located on a concentric circle centered on the axis line CL. The second measurement points M2 are set on the inner circumference side than the first measurement points M1. The second measurement points M2 are set, for example, four at 90° intervals in the circumferential direction centered on the axis line CL. The first measurement points M1 and the second measurement points M2 are set to be aligned along the radial direction centered on the axis line CL.

[0036] With each outer circumference side electrode 21a of the moisture amount measuring unit 21 in contact with each first measurement point M1, a current is passed from each outer circumference side electrode 21a to each first measurement point M1, thereby measuring the amount of moisture contained near each first measurement point M1 on the axial end face 30a of the cake 30. With each inner circumference side electrode 21b in contact with each second measurement point M2, a current is passed from each inner circumference side electrode 21b to each second measurement point M2, thereby measuring the amount of moisture contained near each second measurement point M2 on the axial end face 30a of the cake 30. The moisture amount measuring unit 21 outputs the measured values ​​of the moisture amounts at each first measurement point M1 and each second measurement point M2 to the temperature control unit 23.

[0037] (Weight measurement section 22) The weight measuring unit 22 includes a weight scale (not shown) that measures the weight of the cake 30 taken out from the bobbin 16b of the collet 16. The weight measuring unit 22 outputs the measured value of the weight of the cake 30 taken out from the bobbin 16b to the temperature control unit 23.

[0038] (Temperature control unit 23) Temperature control unit 23 includes, for example, a power source 23a electrically connected to bushing 12. Bushing 12 generates heat when a voltage is applied from power source 23a. The material from which bushing 12 is formed is not particularly limited as long as it is a material that can become a resistance heating element, and examples of the material include metals and ceramics. Examples of metals include molybdenum, platinum, and platinum alloys. Examples of platinum alloys include platinum-rhodium alloys. Temperature control unit 23 is capable of controlling the temperature of the molten glass in bushing 12 by applying a voltage to bushing 12 through power source 23a.

[0039] The temperature control unit 23 controls the temperature of the molten glass in the bushing 12 based on the measured value of the moisture amount of the cake 30 measured by the moisture amount measuring unit 21 and the measured value of the weight of the cake 30 measured by the weight measuring unit 22. For example, the temperature control unit 23 calculates the weight Wm of the moisture contained in the cake 30 based on the average value of the moisture amounts at the measurement points M1, M2. The temperature control unit 23 also calculates the value obtained by subtracting the moisture weight Wm from the measured value of the weight of the cake 30 measured by the weight measuring unit 22 as the weight Wx of the cake itself.

[0040] The temperature control unit 23 controls the temperature of the molten glass in the bushing 12 based on the result of comparing a preset reference value D with the cake body weight Wx. For example, when the cake body weight Wx is equal to or greater than the reference value D, the temperature control unit 23 lowers the temperature of the molten glass in the bushing 12, and when the cake body weight Wx is smaller than the reference value D, the temperature control unit 23 raises the temperature of the molten glass in the bushing 12.

[0041] (Glass fiber manufacturing method) The method for producing glass fibers of this embodiment is carried out using the above-mentioned glass fiber production apparatus 11. The method for producing glass fibers of this embodiment includes a winding step, a removal step including a moisture content measuring step, and a weight measuring step.

[0042] (Winding process) In the winding process, the glass strand S formed from the molten glass flowing out of the bushing 12 is wound around the collet 16 to form a cylindrical cake 30. The winding process ends, for example, when a predetermined time has elapsed from the start.

[0043] (Removal process) After the winding process is completed, a removal process is performed to remove the cake 30 from the collet 16. In the removal process, first, as shown in FIG. 3, the bobbin 16b around which the cake 30 is wound is pushed out in the direction of the axis CL by the push-out part 17, so that the bobbin 16b and the cake 30 are removed from the collet body 16a. At this time, the electrodes 21a, 21b provided on the push-out part 17 contact the axial end face 30a of the cake 30. Then, the moisture amount measuring part 21 measures the moisture amount at a plurality of measuring points M1, M2 on the axial end face 30a of the cake 30 by applying a voltage from each of the electrodes 21a, 21b. That is, in the glass fiber manufacturing method of this embodiment, the moisture amount measuring process for measuring the moisture amount contained in the cake 30 is performed when the bobbin 16b and the cake 30 are removed from the collet body 16a. Then, the cake 30 is removed from the bobbin 16b removed from the collet body 16a.

[0044] (Weight measurement process) In the weight measuring step, the weight of the cake 30 removed from the collet 16 in the removal step is measured by the weight measuring unit 22.

[0045] Thereafter, the temperature control unit 23 calculates the water weight Wm contained in the cake 30 based on, for example, the average value of the water content at each of the measurement points M1 and M2. The temperature control unit 23 also calculates the cake body weight Wx by subtracting the water weight Wm from the measured weight of the cake 30 measured by the weight measurement unit 22. Then, the temperature control unit 23 controls the temperature of the molten glass in the bushing 12 in the next winding process based on the comparison result between the preset reference value D and the cake body weight Wx in the above-mentioned manner. Note that if the cake body weight Wx calculated by the temperature control unit 23 is out of a predetermined appropriate range, the cake 30 is treated as a defective product.

[0046] The effects of this embodiment will be described. (1) The glass fiber manufacturing apparatus 11 includes a moisture amount measuring unit 21 that measures the moisture amount contained in the cake 30, and a weight measuring unit 22 that measures the weight of the cake 30. The glass fiber manufacturing apparatus 11 also includes a temperature control unit 23 that controls the temperature of the molten glass in the bushing 12 based on the moisture amount measured by the moisture amount measuring unit 21 and the weight of the cake 30. The glass fiber manufacturing method using the manufacturing apparatus 11 includes a winding process of forming the cake 30 with the collet 16, a moisture amount measuring process of measuring the moisture amount contained in the cake 30, and a weight measuring process of measuring the weight of the cake 30. The temperature control unit 23 controls the temperature of the molten glass in the bushing 12 in the subsequent winding process based on the moisture amount measured in the moisture amount measuring process and the weight of the cake 30 measured in the weight measuring process. According to this embodiment, the weight of the cake 30 (cake body weight Wx) can be calculated accurately based on the moisture amount contained in the cake 30. Therefore, appropriate temperature control based on the accurate weight of the cake 30 (cake body weight Wx) is possible. Therefore, the occurrence of defective products is suppressed, which contributes to an improvement in yield.

[0047] (2) In the moisture content measuring step, the moisture content is measured by passing an electric current through the cake 30, so that the moisture content in the cake 30 can be suitably measured. (3) In the moisture content measuring process, moisture content measuring points M1, M2 are set on the axial end face 30a of the cake 30. The moisture content in the cake 30 tends to be greater on the outer periphery side due to the centrifugal force during winding. Therefore, by measuring the moisture content on the axial end face 30a of the cake 30, it is possible to measure with higher accuracy than when measuring the moisture content on the outer periphery of the cake 30.

[0048] (4) In the moisture content measuring step, a plurality of measurement points M1, M2 are set at different radial positions on the axial end face 30a of the cake 30. According to this embodiment, the moisture content is measured at a plurality of measurement points M1, M2 at different radial positions on the axial end face 30a of the cake 30, so that the moisture content can be measured with higher accuracy.

[0049] (5) The glass fiber manufacturing apparatus 11 includes an extrusion unit 17 for extruding the cake 30 from the collet 16. The electrodes 21a, 21b included in the moisture content measuring unit 21 are provided in the extrusion unit 17. The moisture content measuring step is performed when the cake 30 is taken out of the collet 16 using the extrusion unit 17 after the winding step. According to this embodiment, it is possible to measure the moisture content of the cake 30 at the same time as taking out the cake 30 from the collet 16. As a result, productivity can be increased.

[0050] (Example of change) This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.

[0051] The moisture content measuring unit 21 in the above embodiment measures the moisture content at a plurality of measurement points M1, M2 on the axial end face 30a of the cake 30, but is not limited thereto, and the measurement point of the moisture content measuring unit 21 may be only one point on the axial end face 30a of the cake 30. In addition, the measurement point of the moisture content measuring unit 21 may be set on the outer circumferential surface of the cake 30.

[0052] In the glass fiber manufacturing method of the above embodiment, the moisture amount measuring step of measuring the moisture amount contained in the cake 30 is performed when the cake 30 is taken out of the collet 16, but this is not particularly limited. For example, the moisture amount measuring step may be performed before or after the taking-out step. Also, for example, the moisture amount measuring step may be performed between the taking-out step and the weight measuring step. Also, for example, the moisture amount measuring step may be performed after the weight measuring step.

[0053] In the above embodiment, the electrodes 21a, 21b of the moisture content measuring unit 21 are provided in the push-out unit 17, but this is not particularly limited. For example, the electrodes of the moisture content measuring unit 21 may be provided in a protective member that is wrapped around the outer periphery of the cake 30 during transportation of the cake 30 removed from the collet 16. In this case, for example, the electrodes provided in the protective member may come into contact with the outer periphery of the cake 30 to measure the moisture content at the outer periphery.

[0054] The moisture content measuring unit 21 in the above embodiment may be a contact moisture meter such as a capacitance type. Note that the contact moisture content measuring unit 21 is preferably not a type in which the electrodes 21a, 21b are inserted into the cake 30, but a type in which the electrodes 21a, 21b come into contact with the cake 30 with a weak pressure. The moisture content measuring unit 21 in the above embodiment may be a non-contact moisture meter such as an infrared type or microwave type.

[0055] The above-mentioned embodiments and modified examples are illustrative in all respects, and the present invention is not limited to these examples. That is, the scope of the present invention is defined by the claims, and it is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0056] 11...Glass fiber manufacturing equipment 12…Bushing 16…Colette 16a…Collet body 16b…Bobbin 17…Extrusion section 21...Moisture content measurement section 22...Weight measurement section 23...Temperature control unit 30…Cake 30a…Axial end face of cake M1: First measurement point M2: Second measurement point S: Glass strand

Claims

1. A method for producing glass fibers, comprising a winding step of winding a glass strand formed from molten glass flowing out of a bushing onto a collet to form a cylindrical cake, a moisture content measuring step of measuring a moisture content contained in the cake formed in the winding step; a weight measuring step for measuring a weight of the cake formed in the winding step; Equipped with a temperature of the molten glass in the bushing in the subsequent winding step is controlled based on the moisture amount measured in the moisture amount measuring step and the weight of the cake measured in the weight measuring step. A method for producing glass fibers.

2. In the moisture content measuring step, the moisture content is measured by passing an electric current through the cake. A method for producing the glass fiber according to claim 1 .

3. In the moisture content measuring step, a measurement point for the moisture content is set on an axial end surface of the cake, A method for producing the glass fiber according to claim 1 .

4. The measurement points on the axial end surface of the cake are set at a plurality of radial positions different from each other. The method for producing the glass fiber according to claim 3 .

5. The moisture content measuring step is carried out when the cake is removed from the collet after the winding step. A method for producing the glass fiber according to claim 1 .

6. a bushing through which the molten glass flows; a collet for winding a glass strand formed from the molten glass flowing out of the bushing to form a cylindrical cake, A moisture amount measuring unit for measuring the moisture amount contained in the cake; A weight measuring unit for measuring the weight of the cake; and a temperature control unit that controls a temperature of the molten glass in the bushing based on the moisture content and the weight of the cake. Glass fiber manufacturing equipment.

7. A push-out unit for pushing the cake out of the collet, The moisture content measuring unit is provided in the extrusion unit. The apparatus for producing glass fibers according to claim 6.

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