JPS60104533A - Preparation of drawn hard twist yarn and device therefor - Google Patents

Abstract

PURPOSE:To carry out continuously drawing of undrawn yarn, twisting and winding of the drawn yarn, and to obtain high-quality drawn hard twist yarn, by griping the drawn yarn, twisting it with forming fixed point of twisting. CONSTITUTION:Undrawn yarn is drawn between a pair of the feed rolls 4 and a pair of the drawing rolls 7, griped by a pair of the positively driving rolls 8 and the single weight roll 9, wound round the surfaces of the rolls 8 and 9 at >=120 deg., and fed to a ring twisting device. Twist made by a traveller is propagated upward, and the twisting point is fixed and kept at a constant position based on a spindle.

Description

[Detailed Description of the Invention] Technical Field> The present invention relates to a method for producing a drawn highly twisted yarn in which a step of drawing an undrawn yarn to produce a drawn yarn, and a step of heating and winding the drawn yarn are consecutively performed, and the method thereof. Regarding manufacturing equipment.

Prior art> Conventionally, undrawn yarn obtained by melt spinning is drawn and
A method and device for winding the material in a manner that improves the convergence by applying so-called translation υ of 5 times/m are known. For example, the second
To explain the case where a so-called drawing and twisting machine as shown in the figure is used, the undrawn yarn 3' (including the yarn obtained by high-speed spinning) pulled out from the pan cage 1' is transferred to the direction changing guide 3' if necessary.
The yarn is fed to a pair of supply rolls 4' via a pair of drawing rolls 7', drawn using a drawing pin 5' and a hot plate 6' if necessary, and then passed through a traveler 10' at high speed. The material is wound onto a cylindrical bobbin 12' in the form of a pirn using a cylinder 11' fitted with a rotating and sliding traveler. In this case, the general drawing speed is about 1000 m for clothing yarn.
/ minute, approximately 500m for yarn for industrial materials such as tire cords
/minute. In addition, the number of revolutions of the bobbin is 10 in the case of clothing.
000 rpm, approximately 5000 rpm for industrial materials
Therefore, the number of twists of the drawn yarn is usually about IO twists/m.

As described above, the yarn obtained by drawing an undrawn yarn produced using a conventionally known method and apparatus is lightly twisted.

Therefore, when making a final product using this yarn, it is necessary to apply a predetermined twist to the yarn through a separate yarn twisting process. For example, when manufacturing raw yarn of 50d to 75d for georgette for clothing, 1500 to 3000 times/m, and when manufacturing raw cord of 800d to 2000d for tire cord, 200 to 550 times/m, or 50d When manufacturing a sewing thread of ~1000 d, twists of 50 to 200 times/m must be applied in a subsequent process. Nowadays, productivity at the melt-spinning stage has improved due to the development of high-speed spinning technology, and there is an urgent need to improve productivity including this post-process.

From this point of view, the inventor of the present invention proceeded with studies on a method and apparatus for successively carrying out the drawing process and the heating process of strong twist, and as a result, encountered a problem that did not occur in the production of conventional lightly twisted drawn yarn. .

One of the problems is that when heating for high twisting is performed using a conventionally known drawing twisting machine, a problem arises in that the final wrapped yarn on the final drawing roll pair 7' falls off from above the roll pair.

This is thought to be because the force acting on the yarn during heating, parallel to the axial direction of the pair of drawing rolls, increases due to strong twisting. That is, the twist applied by the rotation of the traveler of the ring twisting device of the conventionally known drawing and twisting machine propagates upward to form a heating point on the pair of drawing rolls. Since there is no device on the drawing roll pair to suppress the movement of the yarn in the direction parallel to the axial direction of the drawing roll pair, the yarn being heated will move parallel to the axial direction as the tension of the yarn changes. Move left and right in the direction. Furthermore, the root threads that become strongly twisted are biased to one side (to the right in the case of S twist, to the left in the case of 2 twists) due to the influence of the component force. It will fall off more. In order to solve this problem, for example, by increasing the weight of the traveler and increasing the winding tension, it is possible to prevent the yarn from falling off the drawing roll pair 7', but fluff occurs in the wound drawn highly twisted yarn. This is not preferable because the yarn physical properties such as stiffness, strength, and elongation deteriorate.

Another problem is that the fluctuation of the heating point on the drawing roll pair 7' increases the number of twists of the drawn highly twisted yarn. For example, when producing the first twisted yarn of the cord,
With respect to the set number of twists of 90 twists/m, the standard deviation of the variation exceeds 3.3 twists/m, and therefore it is not possible to provide a uniform twist.

Furthermore, as the heating point fluctuates as described above, the highly twisted yarn moves left and right on the surface of the drawing roller pair 7', and the surface of the drawing roller pair 7' is damaged and worn due to friction. A problem arises.

This problem is particularly noticeable when a matte surface finish is applied. If the degree of wear progresses due to long-term operation, there is a risk that the gripping force of the yarn by the pair of stretching rollers 7' will be insufficient and uneven stretching will occur, which is undesirable.

The inventor of the present invention has arrived at the present invention as a result of intensive studies aimed at solving the above-mentioned problems that occur when applying strong twist using a conventionally known twisting machine.

<Purpose of the Invention> The present invention provides a manufacturing method and apparatus for producing drawn strongly twisted yarn that can be stably operated and of good quality when drawing an undrawn yarn and heating and winding the drawn yarn are continuously performed. The purpose is to

<Structure of the Invention> An object of the present invention is to provide a method for producing a drawn highly twisted yarn, which continuously comprises the step of drawing an undrawn yarn to form a drawn yarn, and the step of heating and winding the drawn yarn. This is achieved by a method for producing drawn highly twisted yarn, which is characterized by gripping the yarn to form heating fixing points and then heating it steadily.

Another object of the present invention is an apparatus for producing a drawn high-twisted yarn, comprising a roll drawing device and a ring twisting device arranged downstream of the roll drawing device, the device comprising a heating fixing device, i.e. the heating point is constant with respect to the spindle. This is achieved by an apparatus for producing drawn highly twisted yarn, characterized in that a device for keeping the yarn in position is provided between the roll stretching device and the ring twisting device.

In the apparatus for producing a drawn high-twist yarn, in the traveling direction of the yarn to be processed, the roll drawing device comprises a supply roll pair and a drawing roll pair, and the heating fixing device comprises one or a pair of actively driven rolls. Preferably, the ring twisting device includes a weight roll carried by the positively driven roll, and the ring twisting device includes a ring fitted with a traveler and a heated winding system spindle. With this configuration, the heating point is reliably fixed and high-quality drawn, highly twisted yarn can be stably produced.

Furthermore, a stretching pin and/or a hot plate may be provided between the pair of supply rolls and the pair of stretching rolls of the roll stretching apparatus, if necessary. By configuring the roll drawing device in this manner, it is possible to obtain a uniformly drawn yarn and to impart a uniform strong twist to the uniformly drawn yarn.

<Example> Hereinafter, the present invention will be described in detail with reference to the accompanying drawings showing an example of the apparatus for producing drawn highly twisted yarn according to the present invention.

FIG. 1 shows an embodiment of an apparatus for producing drawn highly twisted yarn according to the present invention. Undrawn yarn (including yarn obtained by high-speed spinning) yarn 3 pulled out from the package 1 is fed to a supply roll pair 4 via a direction changing guide 2. At that time, if necessary, tension may be applied to the undrawn yarn 3 by using a balance or a tension roll to align the single fibers constituting the undrawn yarn. Further, the supply roll pair 4 and the stretching roll pair 7, which will be described later, are usually constituted by a combination of a large-diameter positively driven roll and a small-diameter passively driven roll.

The yarn 3 is then passed through one or more drawing roll pairs 7 (in FIG.
(only one set is shown) and is stretched between the pair of supply rolls 4. Stretch pin 5 to give more uniform stretching
And/or a hot plate 6 may be arranged between the pair of supply rolls 4 and the pair of stretching rolls 7. The drawing speed is usually 3 to 7 m/min for thin undrawn yarns for clothing, while 10 to 200 m/min for thick undrawn yarns for industrial materials.The drawn yarn is then heated. Supplied to the fixation device. 1st
In the embodiment shown in the figure, the heating fixing device is arranged substantially parallel to the pair of stretching rolls 7 and parallel to each other.
It consists of a pair of positively driven rolls 8 and a weight roll 9 supported thereon. The weight roll 9 is preferably a metal roll whose surface is wrapped with an elastic material such as rubber, in order to more reliably grip the thread.

The yarn is gripped by a positive drive roll 8 and a weight roll 9, further wound around the surface of each roll over an angle of 120° or more, and then fed to a ring twisting device. As the heating fixing device, a device having a configuration other than that shown in FIG. 1 can be used as long as it is capable of keeping the heating point at a constant position with respect to the spindle. For example, a heating fixing device consisting of a positively driven roll 8 and a weight roll 9 carried on it and supported by supports may be used.

The thread that has passed through the heating fixing device is inserted into a ring 11 via a Snell wire IO, guided to a travel that rotates and slides at high speed, and then inserted into a spindle and wound around a flanged bobbin 12 that rotates at high speed. The rotation speed of the flanged bobbin 12 is usually s, ooo~ for clothing.
12,00Or,p,ms 5, for industrial materials
000-10', 000 r, p, m.

The twist held by the rotating and sliding traveler of a ring twisting device consisting of a ring equipped with the traveler and a spindle propagates upward and reaches the heating fixing device, but as described above, the yarn is held by the heating fixing device. The heating point is kept fixed at a fixed position relative to the spindle.

The twist given by the traveler is 200 when the drawn yarn is 800 to 3000 d for tire cord cord.
~550 times/rn1 The drawn thread is 50 to 1000 times for sewing thread.
In the case of d, the drawing rate is 50 to 200 times/m2, and in the case of the drawn yarn being 20 to 150 d for clothing, the drawing rate is 1500 to 3000 times/m.

Note that if the yarn is allowed to pass semi-permanently through a certain position of a member constituting the heat fixing device, such as a roller, yarn streaks may be formed in that portion, making it difficult to grip the yarn. Therefore, a yarn traversing device (not shown) may be used in combination with the heating fixing device to prevent the generation of the yarn streaks. In this case, the cycle of yarn traverse is usually long compared to the running length of the yarn, so the heating point can be kept at substantially the same position for a considerable length of yarn that runs continuously. become.

In the device according to the invention, the heating point is kept at a constant position by a heating fixing device newly installed between the roll drawing device and the ring twisting device, so that the heating point is kept at a fixed position by the heating fixing device newly installed between the roll drawing device and the ring twisting device, so that the drawing roll that occurs when using a conventionally known drawing and twisting device is kept at a fixed position. It is possible to solve the problems of yarns falling out of pairs and increased variation in the number of twists of highly twisted yarns. In addition, since the heated yarn does not reach the pair of drawing rolls, the surface of the pair of drawing rolls will not be damaged or worn.

Specific examples of yarn production using the apparatus according to the present invention will be shown below along with comparative examples.

Specific Example Polyethylene terephthalate with an intrinsic viscosity of 0.95 was
Using a spinneret with 4 pores, the spinning temperature was 310
The yarn is spun at °C, the inner surface temperature of a 500 m long heating cylinder is maintained at 350 °C, the yarn is heated, the yarn is cooled and solidified with cold air at 20 °C in a cooling chamber, and the yarn is finished by spinning with an oil roll. After applying the agent, the winding speed was 3100 m/
It was wound up as a drawn yarn in minutes. This undrawn yarn was heated to a diameter of 15 tnm between a pair of supply rolls 4 at room temperature accompanied by a free roll and a pair of drawing rolls 7 at room temperature and having a surface roughness of 2.3S using a stretch twisting device shown in FIG. Using a ceramic stretching bottle 5 and a hot plate at 235°C, the stretching ratio was 2.
．． Stretched 22 times at a stretching speed of 13 m/min, then passed through a heating fixing device in which a weight roll 9 with a weight lif was held by two actively driven rolls 8 at a rotation speed of 6000 rpm.
The material was wound onto a flanged bobbin I2 rotating at a speed of m via a traveler fitted into a ring 11.

During this operation, no yarn fell off from the drawing roll 7, and the number of twists of the obtained drawn strongly twisted yarn was 489.4 twists/m2, and the standard deviation was 2.7 twists/m. Furthermore, there was no change in the surface roughness of the stretching roll 7 before and after continuous operation during the evening months.

Comparative Example Stretching was carried out under the same conditions as in the specific example using the same apparatus shown in FIG. Attempting to manufacture twisted yarn, soon a pair of drawing rolls 7
The yarn of the final wrap of 1' was dropped from the drawing roll pair 7'.

When the number of twists of the drawn highly twisted yarn obtained so far was measured, the number of twists was 486.6, and the standard deviation was 5.0 turns/m. In addition, when we tried continuous operation for one month while using the thread drop prevention guide, the surface roughness of the drawing roll decreased to 1.98.
Wear was observed, and the average number of twists was 487.8 times/m
It increased to

<Effects of the Invention> Since the method and apparatus for producing drawn highly twisted yarn according to the present invention are configured as described above, stable operation can be performed without the yarn falling off from the pair of drawing rolls, and the obtained The drawn highly twisted yarn is a high quality yarn with little variation in twist.

Furthermore, since the pair of drawing rolls is less likely to be damaged, the service life of the apparatus can be extended.

[Brief explanation of drawings]

FIG. 1 is a schematic side view showing an embodiment of an apparatus for producing drawn and highly twisted yarn according to the present invention, and FIG. 2 is a schematic side view showing a conventionally known drawing and twisting machine. 1.1'...undrawn yarn package, 4.4'...supply roll pair, 7.7'...drawing roll pair, 8...positive drive roll, 9...weight roll, 11 ,11'
... Twisting ring, 12.12'... Winding bobbin. Patent applicant: Asahi Kasei Kogyo Co., Ltd. Patent agent: Akira Aoki, patent attorney Kazuyuki Nishidate, patent attorney Akira Yamaguchi, patent attorney Masaya Nishiyama Figure 1 Figure 2

Claims (1)

[Scope of Claims] 1. A method for producing a drawn high-twist yarn in which a step of drawing an undrawn yarn to produce a drawn yarn and a step of heating and winding the drawn yarn are sequentially performed, wherein the drawn yarn is gripped. A method for producing a drawn highly twisted yarn, characterized in that heating is performed while forming a fixed heating point. 2. In a drawn highly twisted yarn manufacturing apparatus comprising a roll stretching device and a ring twisting device disposed downstream of the roll stretching device, a heating fixing device is provided between the roll stretching device and the ring twisting device. An apparatus for producing drawn highly twisted yarn, which is characterized by: 3. In the traveling direction of the yarn to be processed, the roll drawing device includes a pair of supply rolls (4) and a pair of drawing rolls (7). ) and a weight roll (9) carried on said positively driven roll (8), said ring twisting device comprising a ring fitted with a traveler and a heated take-up spindle. Apparatus described in section. 4. The device according to claim 3, wherein a stretching bin (5) and/or a hot plate (6) are provided between the supply roll pair (4) and the stretching roll pair (7) of the roll stretching device.