JP2008063070A - Fluffing degree measuring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluffing degree measuring device for a carbon fiber filament yarn capable of measuring a degree of fluffing on a surface of a carbon fiber filament yarn at a practically effective precision so as to be close to a degree of fluffing in an actual treatment process when conducting various treatment to the carbon fiber filament yarn. <P>SOLUTION: The device for measuring the degree of fluffing of the carbon fiber filament yarn which is rubbed while travelling is equipped with a feed bobbin A of the carbon fiber filament yarn, a tension measuring device B of the travelling carbon fiber filament yarn, a rubbing ring C for moving in a surface vertical to a travelling axis to make a circle around the travelling axis while its inside surface is rubbing the carbon fiber filament yarn so that the carbon fiber filament yarn helically moves around its travelling axis, a variable speed roller D for taking the carbon fiber filament yarn at a predetermined speed and a fluffing degree measuring device E for measuring the degree of fluffing of the carbon fiber filament yarn. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an apparatus for measuring the fluffiness of carbon fiber yarns. More specifically, the present invention is practically effective in reducing the degree of fluff generated on the surface of the carbon fiber yarn when various processing is applied to the carbon fiber yarn, which is close to the amount of fluff in the actual processing step. The present invention relates to a device for measuring the fluffiness of a carbon fiber yarn that can be measured with high accuracy.

  Pitch-based and polyacrylonitrile (PAN) -based carbon fibers are used as reinforcing materials for fiber-reinforced resins in the form of chopped strands or processed into woven fabrics. Moreover, the thing processed into the shape of carbon fiber felt is further cut | disconnected to a predetermined shape, and it is used for an electrode material or a heat generating body.

  These carbon fibers are usually handled as carbon fiber yarns in which a plurality of single fibers are bundled. In the process of processing carbon fiber yarn into a woven fabric, processing into a felt shape, or processing such as cutting, part of the fiber by contact between carbon fibers or contact between the carbon fiber yarn and the processing device Is disconnected. As a result, fluff due to the cut fibers is generated on the surface of the carbon fiber yarn. This fluffing causes instability of operation in the processing process, for example. Furthermore, when the obtained processed product is used for an electrode material or a heating element, it causes a decrease in performance. Therefore, it is important to know the degree of fluffing when processing carbon fiber yarns accurately in order to produce a processed product using carbon fiber yarns with low fuzziness.

  Conventionally, as a fluff inspection apparatus for the surface of a yarn package, a charging means for erecting the fluff at the inspection location on the surface of the yarn package, a light irradiation means for irradiating a predetermined range of space from the surface of the yarn package at the inspection location, and this inspection There is known a fluff inspection apparatus provided with means for picking up an image of a place and a nearby space from the side and detecting fluff from the output signal (Patent Document 1).

  There is also known a fluff detection device that detects fluff of an original yarn by using a pulse-like variation of a specific pattern of untwisting tension during processing of a false twisting machine as a fluff (Patent Document 2).

  However, when these conventional techniques are applied to the measurement of the fluffiness of carbon fiber yarns, the following problems (1) to (3) occur. For this reason, in the conventional fluff detection, the fluffiness of the carbon fiber yarn cannot be measured with practically effective accuracy.

  (1) Since the fluff on the surface of the carbon fiber yarn is rigid, it cannot be made upright by the charging means.

  (2) Since the fluff on the surface of the carbon fiber yarn is poor in toughness, it cannot be false twisted.

  (3) The fluff produced when various processing is applied to the carbon fiber yarn cannot be reproduced with practically effective accuracy.

  A method is known in which the amount of yarn falling per unit time when a yarn is freely dropped from a bobbin is measured, and the unwinding tension of the yarn is measured (see FIG. 6). This method utilizes the correlation between the unwinding tension of the yarn and the amount of yarn falling. However, in the case of carbon fiber yarn having a strong tack force, the yarn does not fall freely.

  As a method of improving the above, measure the amount of fall per unit time when the weight is dropped from the bobbin and dropped, and the amount of load when the yarn is unwound from the bobbin, and the yarn is unwound. A method of measuring the tension can be considered (see FIG. 7). However, the falling speed almost depends on the mass of the weight, and the accurate unwinding tension cannot be measured.

Thus, when various processes are applied to the carbon fiber yarn, a fuzziness measuring device capable of measuring the degree of fuzz generated on the surface of the carbon fiber yarn with a practically effective accuracy in advance has not yet been developed. .
JP-A-7-267498 (Claims) JP 2002-88600 (Claims)

  As a result of various investigations to solve the above problems, the present inventors have found that the fluffiness of carbon fiber yarns subjected to specific rubbing during traveling at a predetermined tension varies in the carbon fiber yarns. It was found that there is a good correlation with the degree of fluffing that occurs when adding.

  The present invention has been completed based on the above discovery, and its purpose is to reduce the degree of fluff generated on the surface of the carbon fiber yarn when various processes are applied to the carbon fiber yarn. Another object of the present invention is to provide an apparatus for measuring the fluffiness of carbon fiber yarns that can be measured with practically effective accuracy.

  The present invention for achieving the above object is as follows.

  [1] A device for measuring the fluffiness of a carbon fiber yarn that has been rubbed during traveling, wherein the carbon fiber yarn is fed from a bobbin (A) and fed from the feeding bobbin (A). The carbon fiber yarn tension measuring device (B), and the inner surface of the carbon fiber yarn is rubbed against the carbon fiber yarn so that the measured carbon fiber yarn spirally moves about its running axis. However, a friction ring (C) that moves circularly about the travel axis in a plane perpendicular to the travel axis, and a variable speed roller that pulls the carbon fiber yarn that has passed through the friction ring (C) at a predetermined speed. (D) and a fuzziness measuring device provided with a fuzziness measuring device (E) that measures the fuzziness of the carbon fiber yarn that has passed through the variable speed roller (D).

  [2] The fluffiness measurement according to [1], wherein a front guide ring (F) and a rear guide ring (G) are provided before the rubbing ring (C) along the running direction of the carbon fiber yarn. apparatus.

  When various processes are applied to the carbon fiber yarn, the degree of fluff generated on the surface of the carbon fiber yarn can be measured with a practically effective accuracy.

  Since the degree of rubbing applied to the carbon fiber yarn can be quantitatively adjusted by the tension of the carbon fiber yarn, etc., various kinds of addition to the carbon fiber yarn in the process of manufacturing the woven fabric using the carbon fiber yarn, etc. The fuzziness can be measured under conditions corresponding to the processing step.

  Since the degree of friction applied to the carbon fiber yarn can be quantitatively grasped by the tension of the carbon fiber yarn or the like, the measurement reproducibility of the generated fluff is good.

  The measurement result of fluffiness can be reflected in the technology for producing carbon fiber yarns with less fuzziness. In particular, when weaving a carbon fiber woven fabric, if the fluffing degree is high, a lint pool is generated in the guide of the loom and the weaving operation becomes an obstacle. The fuzziness measuring device of the present invention is effective in developing a carbon fiber yarn that is free from the above-described obstacles and has good workability.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic view showing an example of the fluffiness measuring apparatus of the present invention. In FIG. 1, 1 is a fluffiness measuring device, and A is a feeding bobbin of the carbon fiber yarn 10. The carbon fiber yarn 10 is fed along the circumferential direction of the bobbin A by a driving force of a variable speed roller D, which will be described later, and travels in the direction of arrow 12 to be sent to the tension measuring device B of the carbon fiber yarn 10. Here, the unwinding tension when the carbon fiber yarn 10 is unwound from the bobbin A is measured.

  Reference numeral 50 denotes a travel axis of the carbon fiber yarn 10.

  The carbon fiber yarn 10 whose unwinding tension is measured by the tension measuring device B is then sent to the rubbing ring C. The friction ring C is a so-called donut-shaped ring having a disc shape with a circular hole formed in the center thereof. This rubbing ring C has means for making a circular motion in a plane perpendicular to the traveling shaft 50 of the carbon fiber yarn 10 with the traveling shaft 50 of the yarn 10 as a circle center.

  When the carbon fiber yarn 10 passes through the central circular hole of the friction ring C, the carbon fiber yarn traveling spirally moves about the traveling axis 50 due to the movement of the circular friction ring C. At the same time, the carbon fiber yarn is rubbed by the inner surface. Reference numeral 30 indicates the locus of the circular motion of the friction ring.

  Next, the carbon fiber yarn 10 that travels in a spiral motion through the circular hole of the friction ring C passes through a variable speed roller D that pulls the carbon fiber yarn at a predetermined speed.

  The carbon fiber yarn 10 that has passed through the variable speed roller D is sent to the fluffiness measuring device E, and the fluffiness of the carbon fiber yarn that has been rubbed by the rubbing ring C is measured.

  FIG. 2 is a schematic view showing another example of the fluff measuring apparatus of the present invention. In FIG. 2, 1 is a fluffiness measuring device, A is a carbon fiber yarn feeding bobbin, 14 is a guide ring for guiding the carbon fiber yarn fed from the feeding bobbin, and 16 is for changing the running direction of the carbon fiber yarn. Guide rolls, 10 is a running carbon fiber yarn, 12 is a running direction of the carbon fiber yarn, B is a tension measuring device for the running carbon fiber yarn (guide rolls 22, 26, a tension measuring roll 24, and a tension measuring device 28). 32 and 34 are guide rolls that change the traveling direction of the carbon fiber yarn, and C is an inner surface so that the traveling carbon fiber yarn spirally moves around the traveling shaft 50. A donut-shaped rubbing ring that circularly moves on a surface perpendicular to the running axis while rubbing the carbon fiber yarn, 30 is a locus of circular movement of the rubbing ring, and F and G are centers formed at the center. Carbon inside the hole A donut-shaped front guide ring and a rear guide ring arranged so that the yarn passes, D is a variable speed roller for picking up the carbon fiber yarn at a predetermined speed, and E is a carbon fiber yarn subjected to friction. It is a fuzziness measuring device which measures the fuzziness of the. The fluffiness measuring apparatus of the present invention preferably includes F and G as means in addition to A, B, C, D and E.

  Each configuration in the present invention will be further described.

[Feeding bobbin (A)]
The feeding bobbin (A) is obtained by winding a carbon fiber yarn to be measured around a cylindrical core in advance. The bobbin may be fixed in rotation by an unwinding type, or may be installed in a state where free rotation is possible.

[Tension measuring device (B)]
The tension measuring device (B) is a device for measuring the tension of the carbon fiber yarn, and a known device can be used. For example, what comprises two sets of guide rolls 22 and 26, the tension | tensile_strength measuring roll 24, and the tension measuring device 28 shown in FIG. 2 can be used. The tension of the carbon fiber yarn can be adjusted by changing the running speed of the carbon fiber yarn by the variable speed roller (D). By adjusting this tension, the strength of friction of the traveling carbon fiber yarn can be adjusted. Accordingly, it is possible to reproduce the frictional strength according to the load on the carbon fiber yarn when various processing is applied to the carbon fiber yarn.

  The tension measured by the tension measuring device (B) has a correlation with the unwinding tension when the carbon fiber yarn is unwound from the feeding bobbin (A). Since this unwinding tension is related to the fluffiness of the carbon fiber yarn, the tension measurement result can be used as an auxiliary to the measurement of the fluffiness. For example, the unwinding tension is related to some degree to the workability when weaving a carbon fiber fabric. However, the above workability cannot be accurately quantified only by measuring the unwinding tension.

  FIG. 3 shows dimensions and the like of the roll group constituting the tension measuring device (B). In FIG. 3, a is the horizontal center distance between the guide rolls 22 and 26, and b is the vertical center distance between the guide rolls 22 and 26 and the tension measuring roll 24. The tension measuring roll 24 can move up and down in the vertical direction, and the rotational axis of the roll 24 is connected to the tension measuring instrument 28 so that the tension can be measured. The distance a between the guide rolls 22 and 26 is preferably increased when the unwinding tension is large.

[Friction ring (C)]
The rubbing ring (C) has an inner surface in a plane perpendicular to the running axis while rubbing the carbon fiber yarn so that the running carbon fiber yarn spirally moves around the running axis. It is a donut-shaped ring that moves circularly. A carbon fiber yarn runs in the central circular hole of the ring. Since the friction ring (C) circularly moves at a constant speed on a plane perpendicular to the running axis of the carbon fiber yarn, the running direction of the carbon fiber yarn is constantly changed by the inner side surface of the ring, and the running axis is changed. Performs a spiral motion centered on. At this time, forced friction (friction) occurs between the carbon fiber yarn and the inner surface of the friction ring (C). The circular motion of the friction ring (C) may be either a right turn or a left turn.

  The rubbing ring (C) preferably has a so-called donut shape having a circular through hole in the center. The material of the ring (C) can be appropriately selected according to the use of the carbon fiber yarn, such as a metal (for example, stainless steel), a resin (for example, polyamide resin), or a ceramic. As the surface of the ring (C), a surface finished to a certain roughness can be used according to the roughness of the contact surface of the carbon fiber yarn in the processing step.

[Front guide ring (F) and rear guide ring (G)]
Each of the front guide ring (F) and the rear guide ring (G) has a donut shape, and preferably has a donut shape having a circular cross section. The carbon fiber yarn travels in the central hole of these rings. With respect to the running direction of the carbon fiber yarn, these rings have the center axis of the central circular hole in the order of the front guide ring (F), the friction ring (C), and the rear guide ring (G) in the running direction of the yarn. Are arranged parallel to each other. With this arrangement, the carbon fiber yarn that has traveled along the travel axis passes through the front guide ring (F), and is then pulled by the friction ring (C) to start a spiral motion around the travel axis. The carbon fiber yarn traveling while being spirally moved returns to traveling along the traveling axis by the rear guide ring (G). By arranging these guide rings before and after the rubbing ring (C), the degree of rubbing applied to the carbon fiber yarn is stabilized. Therefore, the measurement accuracy of the fuzziness increases. The dimensions and shape of the guide rings (F) and (G) are preferably the same as those of the friction ring (C).

  FIG. 4 is a schematic view showing a state of the carbon fiber yarn 36 that spirals in accordance with the circular motion of the rubbing ring (C). 4, 32 and 34 are guide rolls for changing the traveling direction of the carbon fiber yarn, C is a rubbing ring, 30 is a locus of circular movement of the rubbing ring, and 36 is a carbon fiber that spirally moves around the traveling axis 50. Y, F is a front guide ring, G is a rear guide ring, h is an installation interval of the guide ring FG, and r is a turning radius of a circular motion locus of the friction ring. Preferred dimensions of h and r are shown below.

h: 200 to 500 mm
r: 15-100mm
In addition, although the rotational speed of a ring (C) changes with purposes, 10-1000 rpm is preferable.

[Variable speed roller (D)]
The variable speed roller (D) has a function of causing the carbon fiber yarn fed from the feeding bobbin (A) to run at a constant running speed. With this roller, the running speed and unwinding tension of the carbon fiber yarn can be determined. The running speed of the carbon fiber yarn varies depending on the purpose, but is preferably 1 to 30 m / min.

[Fuzziness measuring device (E)]
The fuzziness measuring device (E) is a device for measuring the fuzziness of the carbon fiber yarn subjected to friction, and a known device can be used. An apparatus that collects fluff and measures its mass is preferred.

[Example 1]
The following examples further illustrate the present invention.

  The fluffiness of the carbon fiber yarn was measured using an apparatus similar to the fluffiness measurement apparatus shown in FIG. On the pay-out bobbin (A) having a diameter of 250 mm, as a carbon fiber yarn, Besphite (registered trademark) manufactured by Toho Tenax Co., Ltd. (total number of single fibers: 12,000, single fiber 0.11 dtex wound around 4000 m) Was used. The bobbin was installed with the bobbin axis aligned with the feeding direction as shown in FIG.

  In the tension measuring device (B), the horizontal center distance a between the guide rolls 22 and 26 in FIG. 3 is 100 mm, and the vertical center distance b between the guide rolls 22 and 26 and the tension measuring roll 24 is 10 mm. Met.

  The surface roughness of the rubbing ring (C), the front guide ring (F), the rear guide ring (G), and the guide ring (14) was Ra = 0.05 μm (Rmax = 0.90 μm). The rotation radius r of the friction ring (C) circular motion locus was 300 mm, the rotation speed was 750 rpm, and the installation interval h of the guide ring FG was 500 mm.

  The constant running speed of the carbon fiber yarn was 10 m / min by the variable speed roller (D). The tension of the run carbon fiber yarn was measured to be 190 cN by the tension measuring device (B). The fluffiness of the carbon fiber yarn subjected to rubbing under the above conditions was measured with a fluffiness measuring device (E). As a result of the measurement, the fuzziness was 39.4 μg / m (12 μg / ft).

  The fuzziness measuring device (E) used was a system that sandwiched carbon fiber yarns running on a urethane material and measured the mass of carbon fibers (fluff) attached to the urethane material. The above tension is a high tension that cannot be measured by a conventional measuring method.

[Example 2]
As shown in FIG. 5, the bobbin core is inserted into a rotating shaft (not shown), the unwinding direction is set perpendicular to the bobbin axial direction in a state where free rotation is possible, and the measurement conditions are as follows: Except for the change, the fluffiness of the carbon fiber yarn was measured in the same manner as in Example 1. As a result of the measurement, the fuzziness was 32.8 μg / m (10 μg / ft).

  In the tension measuring device (B), the horizontal center distance a between the guide rolls 22 and 26 in FIG. 3 is 150 mm, and the vertical center distance b between the guide rolls 22 and 26 and the tension measuring roll 24 is 20 mm. The thing of was used.

  The constant running speed of the carbon fiber yarn was 20 m / min. The tension of the run carbon fiber yarn was measured to be 30 cN.

It is the schematic which shows an example of the fluffiness measuring apparatus of this invention. It is the schematic which shows the other example of the fluff degree measuring apparatus of this invention. It is the schematic which shows an example of the tension measuring apparatus (B) used for this invention. It is the schematic which shows the state of the carbon fiber yarn 36 which carries out a spiral motion with the circular motion of a friction ring (C). It is the schematic which shows an example of the fluffiness measuring apparatus used for the Example of this invention. It is the schematic which shows the example of the method of measuring the unwinding tension | tensile_strength of a yarn. It is the schematic which shows the example of the method of measuring the unwinding tension | tensile_strength of a yarn.

Explanation of symbols

A feeding bobbin B tension measuring device C friction ring D variable speed roller E fluffiness measuring device F front guide ring G rear guide ring 1 fluffiness measuring device 10 traveling carbon fiber yarn 12 running direction of carbon fiber yarn 14 Guide ring 16 Guide roll 22 Guide roll 24 Tension measurement roll 26 Guide roll 28 Tension measuring instrument 30 Trajectory of circular motion of friction ring 32 Guide roll 34 Guide roll 50 Advancing axis of carbon fiber yarn a Guide roll 22 and guide roll 26 B Horizontal center distance b Vertical distance between guide rolls 22 and 26 and tension measuring roll 24
h Guide ring FG installation interval r Rotating radius of the circular motion locus of the friction ring

Claims (2)

An apparatus for measuring the fluffiness of a carbon fiber yarn that has been rubbed during traveling, the carbon fiber yarn feeding bobbin (A) and the carbon fiber fed from the feeding bobbin (A) and running The yarn tension measuring device (B) and the running while the inner surface of the yarn is rubbed against the carbon fiber yarn so that the carbon fiber yarn whose tension is measured spirals around the running axis. A friction ring (C) that moves circularly about a running axis in a plane perpendicular to the axis, and a variable speed roller (D) that pulls the carbon fiber yarn that has passed through the friction ring (C) at a predetermined speed And the fluffiness measuring device provided with the fluffiness measuring device (E) which measures the fluffiness of the carbon fiber yarn which passed the variable speed roller (D). The fluffiness measuring device according to claim 1, wherein a front guide ring (F) and a rear guide ring (G) are provided in front of the rubbing ring (C) and rear guide ring (G) along the running direction of the carbon fiber yarn.

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