JP7027086B2 - Manufacturing method for false twister discs and false twister discs - Google Patents

Description

The present disclosure relates to discs for false twisters.

Conventionally, in order to twist the yarn, a method of contacting a plurality of rotating false twisting machine discs has been used. It is known that such a false twisting machine disc is made of ceramics (see Patent Document 1).

Japanese Unexamined Patent Publication No. 8-337936

When the false twister disk is made of ceramics, the ceramics have excellent mechanical properties and therefore have excellent durability. However, due to its excellent mechanical properties, it should not cause great damage to the yarn to be twisted, and this damage can be judged by the size of the wear debris generated when twisting. Therefore, the false twisting machine disc is required to have a small amount of wear debris generated when twisting.

It is an object of the present disclosure to provide a false twisting machine disc having excellent durability and less wear debris generated when twisting a yarn.

The disc for false twister of the present disclosure is a disk-shaped body made of ceramics, and the average value of the average length RSm on the contact surface with the yarn is 0.12 mm or more, and the variation of the average length RSm. The coefficient is 0.15 or less .
In the method for manufacturing a disc for a false twister of the present disclosure, after forming a convex curved outer peripheral surface by grinding a disk-shaped sintered body, JIS R 6001-1: 2017 and JIS are used as abrasive grains. A medium composed of a green silicon carbide abrasive and aluminum oxide having a particle size number of F150 to F240 specified in R 6001-2: 2017 is put into a barrel together with the sintered body, and the sintered body and the media are charged. Gives vibration to.
In another method for manufacturing a disc for a false twister of the present disclosure, a disk-shaped sintered body is ground to form a convex curved outer peripheral surface, and then JIS R 6001-2: 2017 is used as abrasive grains. The outer peripheral surface is ground using a grindstone provided with a green silicon carbide abrasive having a particle size number of # 700 to # 1000 specified in 1.

The disc for a false twisting machine of the present disclosure is excellent in durability and generates less wear debris when twisting the yarn.

An example of the false twisting machine disc of the present disclosure is shown, (a) is a perspective view, (b) is a sectional view, and (c) is a schematic view showing a state in which a yarn is twisted. .. It is a schematic diagram of the false twisting machine provided with the disk for false twisting machine of this disclosure.

Hereinafter, embodiments of the false twister disc of the present disclosure will be described in detail with reference to the drawings. 1A and 1B show an example of a false twisting machine disc of the present disclosure, FIG. 1A is a perspective view, FIG. 1B is a cross-sectional view, and FIG. 1C is a schematic representation showing a state in which a yarn is twisted. It is a figure. FIG. 2 is a schematic view of a false twisting machine provided with the false twisting machine disc of the present disclosure.

The false twister disk 10 (hereinafter, simply referred to as a disk) shown in FIG. 1 is a disk-shaped body made of ceramics, and has a flat first main surface 1 and a second main surface 2 and a first main surface. It is provided with an outer peripheral surface 3 which is connected to 1 and the second main surface 2 and has a convex curved surface shape, and a through hole 4 penetrating the first main surface 1 and the second main surface 2.

In the disc 10, the shaft body 5 shown in FIG. 2 is inserted and fixed in the through hole 4, and the disc 10 rotates with the rotation of the shaft body 5. Then, when the yarn S is twisted using the disc 10, the yarn S is pressed against the outer peripheral surface 3 of the disc 10 as shown in FIG. 1 (c). In the following, the portion of the outer peripheral surface 3 in contact with the thread S will be described as the contact surface 3a. Here, the thread S is a fiber made of, for example, polyamide or polyester. Although the disk 10 has an example of having a through hole 4 in FIG. 1, it may be fixed to the shaft body 5 in the false twisting machine 20, and may not necessarily have the through hole 4. It's not a thing.

The disc 10 is made of, for example, ceramics containing aluminum oxide, silicon carbide, or aluminum nitride as a main component. Since the ceramics containing the above components as the main component have high thermal conductivity, the heat generated by the sliding contact with the yarn S can be quickly dissipated.

Here, the main component of the ceramics means a component that occupies 80% by mass or more of the total 100% by mass of the components constituting the ceramics. The components may be identified by collating with a JCPDS card using an X-ray diffractometer.

As for the content of the component, the content of the metal element constituting the component is determined by a fluorescent X-ray analyzer (XRF) or an ICP (Inductively Coupled Plasma) emission spectrometer (ICP), and an X-ray diffractometer is used. It may be converted into the identified compound.

Here, when the disc 10 is made of ceramics containing aluminum oxide as a main component, it is required for the disc 10 while being relatively easy to process into a desired shape as compared with ceramics containing silicon carbide or aluminum nitride as a main component. It has mechanical properties and is inexpensive. Among the ceramics containing aluminum oxide as a main component, the ceramics having an aluminum oxide content of 99% by mass or more are excellent in thermal conductivity.

In the disc 10 of the present disclosure, the average value of the average length RSm on the contact surface 3a is 0.12 mm or more.

Here, the average length RSm represents the average length of the contour curve elements at the reference length. The length of the contour curve element is the length from the entrance (start point) of the valley to the exit (end point) of the mountain in a set of valleys and mountains connected in the reference length direction. Further, the fact that the numerical value of the average value of the average length RSm is large means that the distance between the peaks that are convex portions on the contact surface 3a is wide.

The disc 10 of the present disclosure is excellent in durability in that it is made of ceramics, and since the average value of the average length RSm on the contact surface 3a is 0.12 mm or more, the convex portion on the contact surface 3a. Since the distance between certain ridges is wide and there are few contacts with the threads S, wear debris is unlikely to occur.

Further, the coefficient of variation of the average length RSm may be 0.15 or less. Here, the coefficient of variation is a value obtained by dividing the standard deviation by the value of the average length RSm, and is used to relatively evaluate the relationship between the target value and the standard deviation, and the value of this coefficient of variation. The smaller the value, the smaller the variation with respect to the value of the average length RSm. When the coefficient of variation of the average length RSm is 0.15 or less, the variation in the surface texture of the contact surface 3a is small, so that the variation in the contact method of the threads S is small, and therefore the wear debris is more. It is less likely to occur.

Further, the disk 10 may have an average value of the ratio (Rsm / Ra) of the average length RSm to the arithmetic average roughness Ra on the contact surface 3a of 150 or more.

The ratio (RSm / Ra) of the average length RSm to the arithmetic average roughness Ra on the contact surface 3a is such that the distance between the peaks that are convex portions on the contact surface 3a is wide, or the arithmetic average roughness Ra is small, or both. The value increases when it is met. When the average value of the ratio (RSm / Ra) on the contact surface 3a is 150 or more, the number of contacts with the yarn S is small, so that abrasion powder is less likely to be generated.

The ratio on the contact surface 3a (the number of yarn twists, the yarn strength, the yarn elongation, the yarn crimp ratio, etc.) is excellent because it has an excellent false twisting force due to moderate friction. The upper limit of the average value of Rsm / Ra) is, for example, 500 or less.

Further, the disk 10 may have a coefficient of variation of the ratio (Rsm / Ra) of 0.2 or less. When the coefficient of variation of the ratio (RSm / Ra) on the contact surface 3a is 0.2 or less, the number of contacts with the yarn S is small and the variation in surface texture is small, so that abrasion powder is less likely to be generated.

Further, the disk 10 may have an average value of the maximum mountain height Rp on the contact surface 3a of 3.5 μm or less. When the average value of the maximum mountain height Rp is 3.5 μm or less, the convex portion on the contact surface 3a tends to have a gentle top shape, so that abrasion powder is less likely to be generated. Further, there is less possibility that a part of the convex portion on the contact surface 3a is chipped or the entire convex portion is chipped off due to the partial chipping.

Further, in the disk 10, the average value of the skewness Rsk on the contact surface 3a may be a negative value. When the average value of the skewness Rsk on the contact surface 3a is a negative value, the shape of the convex portion on the contact surface 3a is rounded like a bell, so that the damage to the thread S is reduced. , Wear debris is less likely to occur.

The parameters indicating various surface properties are based on JIS B 0601-2001 and can be measured using a surface roughness measuring machine (manufactured by Kosaka Laboratory Co., Ltd., surf coder (SE500A or its successor model)). .. As the measurement conditions, parabolic measurement may be used, the radius of the stylus may be 5 μm, the measurement length may be 2 mm (the traveling direction of the thread), the cutoff value may be 0.8 mm, and the scanning speed may be 0.1 mm / sec. .. Further, the number of measurement points may be eight or more at substantially equal intervals along the outer peripheral surface.

FIG. 2 is a schematic view of a false twisting machine using the false twisting machine disc of the present embodiment.

The false twisting machine 20 shown in FIG. 2 includes a plurality of shaft bodies 5 (5a, 5b, 5c) installed at predetermined intervals, and disks 10 (10a, 10b, 10c) are attached to these shaft bodies 5a, 5b, and 5c. ) Are located at predetermined intervals. The disks 10a, 10b, and 10c are arranged so that at least a part of the disks 10a, 10b, and 10c overlap each other in the top view. The shaft bodies 5a, 5b, and 5c are rotatably supported by the plate 6 arranged on the lower side, the shaft bodies 5a and 5b are on the belt 7 (7a), and the shaft bodies 5b and 5c are on the belt 7 ( It is connected to 7b). The shaft body 5b is also connected to a drive belt located below.

Further, a guide disk 8 to which the thread S first contacts is located at the uppermost portion of the shaft body 5a. The guide disc 8 may have the same shape as the disc 10. Further, a truncated cone-shaped knife edge disc 9 is located at the portion where the thread S finally contacts.

In the drive of the false twister 20, the shaft body 5b is rotated by the drive source via the drive belt, and the shaft bodies 5a and 5c are rotated by the belts 7a and 7b in the same direction as the rotation direction of the shaft body 5b. Along with this, the guide disc 8, the disc 10, and the knife edge disc 9 rotate. Then, when the yarn S is run so as to be in sliding contact with each disc, the yarn S is twisted by the frictional force at the time of sliding contact with the disc 10.

Next, as an example of the method for manufacturing the false twister disc of the present embodiment, a case where the false twister disc is made of ceramics containing aluminum oxide as a main component will be described.

First, aluminum oxide powder, which is the main component, magnesium hydroxide, silicon oxide, and calcium carbonate powder, a dispersant that disperses aluminum oxide powder, if necessary, and an organic binder are mixed with a ball mill, bead mill, or vibration. Wetly mix with a mill to make a slurry.

Here, the average particle size (D ₅₀ ) of the aluminum oxide powder is 3 μm or less, preferably 1 μm or less, and the content of the magnesium hydroxide powder in a total of 100% by mass of the powder is 0.3 to 0.4% by mass. The content of the silicon oxide powder is 0.02 to 0.04% by mass, and the content of the calcium carbonate powder is 0.045 to 0.055% by mass.

The wet mixing time is, for example, 40 to 50 hours. The organic binder is, for example, paraffin wax, wax emulsion (wax + emulsifier), PVA (polyvinyl alcohol), PEG (polyethylene glycol), PEO (polyethylene oxide) and the like.

Next, the slurry obtained by the above-mentioned method is spray-granulated to obtain granules, and then the granules are molded by a powder press molding method to obtain a disk-shaped molded body having through holes. Then, the obtained molded product is fired at a temperature of 1600 ° C. or higher and 1800 ° C. or lower to obtain a sintered body.

Next, the outer peripheral surface having a convex curved surface is formed by grinding the sintered body with a grindstone having a diamond having a particle size number of, for example, # 325. After that, the disc of the present embodiment can be obtained by subjecting at least the outer peripheral surface to a barrel vibration treatment or a grinding process. The convex curved outer peripheral surface may be formed at the time of molding. Further, as the surface texture of the outer peripheral surface, a mold having a surface texture in consideration of the change in the surface texture in the barrel vibration treatment may be used.

In the following, the target surface will be described as an outer peripheral surface in order to describe a method for obtaining a desired surface texture not only on the contact surface but also on the outer peripheral surface including the contact surface.

In order to make the average value of the average length RSm on the outer peripheral surface 0.12 mm or more, JIS R 6001-1: 2017 and JIS R 6001-2: 2017 are specified as abrasive grains when performing barrel vibration treatment. Using a medium made of GC (green silicon carbide abrasive) having a particle size number of F150 to F240 and aluminum oxide, the material may be put into a barrel together with a sintered body and vibrated for 10 hours or more and 14 hours or less.

When grinding is performed, a grindstone having a GC having a particle size number of # 700 to # 1000 specified in JIS R 6001-2: 2017 may be used as the grindstone. As described above, in the barrel vibration processing and the grinding process, the surface texture of the outer peripheral surface can be controlled by adjusting the size of the GC.

Further, in order to obtain a disk having an average value of the ratio (Rsm / Ra) of the average length RSm to the arithmetic mean roughness Ra on the outer peripheral surface of 150 or more, the GC (grain size number is F180, F220, F230 or F240). A medium made of green silicon carbide abrasive) and aluminum oxide may be used and put into a barrel together with the sintered body to give vibration for 11 hours or more and 14 hours or less.

Further, in order to obtain a disc having an average value of the maximum mountain height Rp on the outer peripheral surface of 3.5 μm or less, a medium made of GC (green silicon carbide abrasive) having a particle size number of F220, F230 or F240 and aluminum oxide is used. It may be put into a barrel together with a sintered body and subjected to vibration for 11 hours or more and 14 hours or less.

Further, in order to obtain a disk in which the average value of the skewness Rsk on the outer peripheral surface is a negative value, a medium made of GC (green silicon carbide abrasive) having a particle size number of F220, F230 or F240 and aluminum oxide is used. It may be put into a barrel together with the sintered body and subjected to vibration for 12 hours or more and 14 hours or less.

Hereinafter, examples of the present invention will be specifically described, but the present invention is not limited to these examples.

First, aluminum oxide powder, which is the main component, magnesium hydroxide, silicon oxide, and calcium carbonate powder, a dispersant that disperses aluminum oxide powder, and an organic binder are wet-mixed by a ball mill to form a slurry. ..

Here, the average particle size (D ₅₀ ) of the aluminum oxide powder is 1 μm or less, the content of the magnesium hydroxide powder is 0.37% by mass, and the content of the silicon oxide powder is 0 in the total 100% by mass of the powder. The content was 0.03% by mass and the content of the calcium carbonate powder was 0.052% by mass. The wet mixing time was 45 hours.

Next, the slurry obtained by the above-mentioned method is spray-granulated to obtain granules, and then the granules are molded by a powder press molding method to form a disk-shaped molded body having a through hole on the axis. Got Then, the molded product was fired at 1700 ° C. to obtain a sintered body.

Then, on the outer peripheral surface of the sintered body, an outer peripheral surface having a convex curved surface was formed by grinding with a grindstone having a diamond having a particle size number of # 325.

Next, the sample No. For the sintered bodies of 2 to 4, the GC having the particle size number shown in Table 1 and the medium made of aluminum oxide were used, and the sintered body was put into a barrel together with the sintered body and subjected to barrel vibration treatment for the time shown in Table 1. .. Sample No. The sintered body of No. 1 was not subjected to barrel vibration treatment.

Then, the average length RSm of the contact surface of each sample was measured according to JIS B 0601-2001 using a surface roughness measuring machine (manufactured by Kosaka Laboratory Co., Ltd., surf coder (SE500A)). Using parabolic measurement, the radius of the stylus was 5 μm, the measurement length was 2 mm, the cutoff value was 0.8 mm, and the scanning speed was 0.1 mm / sec. The measurement was performed so as to include the most protruding portion in the radial direction on the outer peripheral surface and in the traveling direction of the thread. In addition, the measurement points were set to 8 points at substantially equal intervals in the circumferential direction, respectively. Table 1 shows the average value of the measured values at eight points of the sample.

Next, each sample was mounted on a false twisting machine, and the yarn was falsely twisted. As the yarn to be false twisted, a polyamide having a diameter of 4d (denier) / f (filament) was used. Then, the mass of the wear debris after false twisting was measured, and the sample No. Table 1 shows the relative values of 1 with the mass of the wear debris.

As shown in Table 1, the sample No. 2 to 4 are sample Nos. The amount of wear debris generated was less than 1. From this result, it was found that by setting the average value of the average length RSm on the contact surface to 0.12 mm or more, it is possible to prevent the generation of wear debris.

A sintered body having a convex curved outer peripheral surface is formed by the same method as described in Example 1, and then charged into a barrel together with a medium having a particle size number of GC and aluminum oxide shown in Table 2 and shown in Table 2. Barrel vibration treatment was performed for the indicated time, and the sample No. 5-9 was obtained. In addition, sample No. Reference numeral 5 is the sample No. 5 in Example 1. It is the same sample as 3.

Then, the arithmetic average roughness Ra and the average length RSm of the contact surface of each sample were measured at 8 points by the same method as shown in Example 1. Then, the ratio (RSm / Ra) was calculated from each of the obtained measured values, and the average value of the calculated values is shown in Table 2.

Further, as in Example 1, each sample was mounted on a false twisting machine, false twisting of the yarn was performed under the same conditions, and the mass of the wear debris after false twisting was measured. Table 2 shows the relative values of No. 5 with the mass of the wear debris.

As shown in Table 2, the sample No. 6 to 9 are sample Nos. The amount of wear debris generated was less than that of 5. From this result, it was found that when the average value of the ratio (Rsm / Ra) on the contact surface is 150 or more, wear debris can be less likely to be generated.

A sintered body having a convex curved outer peripheral surface is formed by the same method as described in Example 1, and then charged into a barrel together with a medium having a particle size number of GC and aluminum oxide shown in Table 3.
Barrel vibration treatment was performed for the time shown in Table 3, and the sample No. Obtained 10-14. In addition, sample No. Reference numeral 10 is the sample No. 10 in Example 1. It is the same sample as 4.

Then, the maximum mountain height Rp of the contact surface of each sample was measured by the same method as shown in Example 1, and the average value of the measured values at eight points is shown in Table 3.

Further, as in Example 1, each sample was mounted on a false twisting machine, false twisting of the yarn was performed under the same conditions, and the mass of the wear debris after false twisting was measured. Table 3 shows the relative values of 10 to the mass of the wear debris.

As shown in Table 3, the sample No. 11 to 14 are sample Nos. The amount of wear debris generated was less than 10. From this result, it was found that when the average value of the maximum mountain height Rp on the contact surface is 3.5 μm or less, wear debris can be less likely to be generated.

A sintered body having a convex curved outer peripheral surface is formed by the same method as described in Example 1, and then charged into a barrel together with a medium having a particle size number of GC and aluminum oxide shown in Table 4 and shown in Table 3. Barrel vibration treatment was performed for the indicated time, and the sample No. Obtained 15-19. In addition, sample No. Reference numeral 15 is the sample No. 15 in Example 3. It is the same sample as 11.

Then, the skewness Rsk of the contact surface of each sample was measured by the same method as shown in Example 1, and the average value of the measured values at eight points is shown in Table 4.

Further, as in Example 1, each sample was mounted on a false twisting machine, false twisting of the yarn was performed under the same conditions, and the mass of the wear debris after false twisting was measured. Table 4 shows the relative values of the wear debris of 15 with respect to the mass.

As shown in Table 4, the sample No. 16 to 19 are sample Nos. The amount of wear debris generated was less than 15. From this result, it was found that the average value of the skewness Rsk on the contact surface is a negative value, so that wear debris can be less likely to be generated.

1: 1st main surface 2: 2nd main surface 3: Outer peripheral surface 3a: Contact surface 4: Through hole 5: Shaft body 6: Plate 7: Belt 8: Guide disk 9: Knife edge disk 10: Disk for false twister 20: False twister S: Thread

Claims (5)

It is a disk-shaped body made of ceramics, and has an average value of RSm of average length RSm on a contact surface with threads of 0.12 mm or more, and a coefficient of variation of the average length RSm of 0.15 or less. Machine disk. The disk for a false twister according to claim 1, wherein the average value of the ratio of the average length RSm to the arithmetic average roughness Ra on the contact surface is 150 or more. The disc for a false twister according to claim 1 or 2, wherein the average value of the maximum mountain height Rp on the contact surface is 3.5 μm or less. The disk for a false twister according to any one of claims 1 to 3, wherein the mean value of the skewness Rsk on the contact surface is a negative value. After forming a convex curved outer peripheral surface by grinding a disk-shaped sintered body, the grain size numbers specified in JIS R 6001-1: 2017 and JIS R 6001-2: 2017 as abrasive grains are used. Manufacture of a disk for a false twisting machine in which a medium made of a green silicon carbide abrasive having F150 to F240 and aluminum oxide is put into a barrel together with the sintered body to give vibration to the sintered body and the media. Method. _

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