JPS6128035A - False twisting method and apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a false twisting method and apparatus. More specifically, the present invention relates to a method and apparatus for shortening the time for heat-setting false twisting using a heating roller and performing false twisting at high speed and stably.

[Prior art and its problems]

False-twisting processing is becoming faster due to advances in simultaneous stretching and simultaneous false-twisting technology and friction twisting devices. However, little effective improvement has been observed in the heat setting technology of false twisting.
This is simply a matter of maintaining the heat setting time and increasing the speed. For this reason, the heater has become longer, 2 to 3 meters long, and the false twisting machine has become extremely large. This is not only a matter of workability, but also involves physical problems such as an increase in the power consumption of the heater and an expansion of the building space. More dogs @
Another problem is that the distance between the supply roller and the twisting device increases, which makes workability unstable and becomes an obstacle to increasing the speed, making it impossible to significantly increase the speed.

In order to solve these problems, several attempts have been made to shorten the heat fixation zone. Special Public Service 1977
No. 9151 and Japanese Unexamined Patent Publication No. 116353/1987 disclose a method in which yarn is wound around a heating roller and subjected to a false twisting process.
Although it is possible to shorten the heat-setting zone, in either method, when the yarn is heated, it vibrates on the heating roller surface, making false twisting unstable and the heat-setting effect not being uniform. Therefore, good crimped yarn cannot be obtained. This phenomenon is especially noticeable as the speed increases.
Practical implementation is difficult. JP-A-50-48209 discloses a method in which the yarn is nipped by an elastic roller on a heating roller to prevent the propagation of false twisting, and although the instability described above is improved, the surface temperature of the heating roller is rattling 100
It is c.

In addition, since the elastic nip roller is not heated, the yarn temperature at the nip point, especially the temperature on the nip roller side, is lower than the surface temperature of the heating roller, and the once heated yarn is cooled in this area, reducing the heat fixing effect. Therefore, it hardly contributes to shortening the heat setting time of false twisting, and a long hot plate must be used as in the past.

[Object of the present invention]

The present invention provides a processing method and apparatus for efficiently performing heat setting using heating rollers to obtain uniformly high-quality crimped yarns at high speed. It is something to do.

[Configuration of the present invention]

In order to achieve the above object, the present invention consists of the following configuration.

[(1) In a false twisting method in which a thermoplastic synthetic fiber yarn is false-twisted and heat-set using at least two heating rollers, a substantially untwisted yarn is heated with a heating roller A to raise its temperature. A false-twisting method characterized by using a pair of heating rollers that then thermally fix the false twist using a heating roller B while imparting false twist to the heated yarn without lowering its temperature.

(2) In an apparatus for false-twisting thermoplastic synthetic fiber yarn, a yarn supply means, a pair of at least two heating rollers, a stirring device, and a 9-winding device are arranged in this order from the upstream side. A false-twisting processing apparatus characterized in that the false-twisting processing apparatus is provided with an adjustment mechanism that allows adjusting the mutual gap between the pair of heating rollers A and B consisting of the at least two heating rollers. ” When heat-setting false twist using heated rollers.

An important point in heat setting is to impart false twist to the heated yarn without lowering its temperature. By using.

It has been found that the object of the invention is achieved. That is,
Regarding a pair of heating rollers A and B, heating roller A disposed upstream of the running yarn heats the yarn in a substantially untwisted state to raise the temperature. The term "substantially untwisted yarn" as used herein includes the number of twists caused by original twisting of the supplied raw yarn or untwisting from the package on the heating roller A.

The number of twists at which the single yarns constituting the yarn can take a flat arrangement is the limit. Therefore, most of the single yarns constituting the yarn are heated on the heating roller A while being in contact with each other, and the heat is transferred to the heating roller A for each single yarn, so that the temperature rises in a very short time.

Therefore, when the processing speed is at a high speed of 1000 m/min or more, the temperature increase by the heating roller A makes a significant and effective contribution. The contact time t of the traveling yarn with the heating roller A is expressed as a function of the fineness of the single yarn constituting the yarn, and is preferably in the range D, 0D2a≦t≦002d. Diameter of heating roller A.

Surface roughness 1 varies depending on the surface speed, set temperature, type of supply system, etc., but if t is less than 0002d, the heating temperature of the yarn is insufficient, and the heat setting of false twisting tends to be unsatisfactory. Become. If t exceeds 0.02 d, the temperature of the yarn will be increased sufficiently, but it will take an hour longer and crystallization of the fibers will progress.

The heating roller B heats and fixes the false twist of the heated yarn, which is applied by a twisting device to a yarn whose temperature has been sufficiently raised. It is important not to reduce the temperature when moving from heating roller A to heating roller B. For this purpose, it is preferable that the heating port A and the heating roller B be very close to each other, and that the yarn has a gap S within the range of the diameter d of the single yarn and the diameter of the heating yarn. In other words, dkuSkuD
Due to this, the false twist imparted by the twisting device is propagated to this gap S section.

It does not propagate onto heating roller A at all. The false twist imparted on heating roller B is heat-set. Here, if S is smaller than d, the single yarn will be crushed, resulting in a tendency for the cross section to become flat or for the single yarn to be cut. When the cross section of the single yarn of the supplied yarn is irregular, it means the width of the minimum minor axis.

The yarn passing through the gap formed by heating roller A and heating roller B comes into contact with heating roller B while being heated, and this angle is preferably 90 or less.

From the standpoint of heat setting during false twisting, it is better to set the contact angle as large as possible since this increases the heat treatment time.

Since the temperature of the yarn is raised by the heating roller A, it will not be made unnecessarily long. When the false twist is propagated to the yarn still in contact with the heating roller B, the yarn rotates and vibrates while rolling due to friction with the roller surface. This vibration, along with fluctuations in tension, induces instability in the number of twists and a reduction in the heat-setting effect, making it impossible to obtain a uniform crimped yarn. Diameter 2 of heating roller B, surface roughness, processing speed.

Although it varies depending on the supplied yarn, etc., if the contact angle of the heating yarn on the heating roller exceeds 90, the above-mentioned problems will occur, which is undesirable. Next, heating roller A and heating roller B
Regarding the temperature relationship between B and B, it is more effective to set the temperature of B higher than that of B from the viewpoint of heat setting of false twisting. However, if the temperature is higher than the melting point of the yarn, problems such as a decrease in the fluff strength of the resulting crimped yarn or yarn breakage occur. Further, even if the temperature of the heating roller A is lowered, the heating of the yarn is insufficient, and the heat fixing effect of false twisting is reduced. Therefore, the temperature of the heating roller B is set based on the melting point of the yarn, and the temperature of the heating roller A is set several points lower than the melting point based on the fluctuation of the heated yarn in the twisting zone. It is well known that this condition worsens as the false twisting speed increases. In order to prevent this, it is common to increase the tension of the yarn in the heating zone to stabilize it. However, the false twisting speed is 1000 m/m.
If the tension exceeds 1 inch, even if it becomes necessary to significantly increase the tension, the strength will decrease by 9 fluffs and the problem of yarn breakage will occur. Regarding this point, the present invention uses a heating roller that can greatly shorten the length of the heat setting device for false twisting, and to further increase the speed, a water bath or forced cooling device using water adhesion to cool the heated yarn is used. By arranging the heating zone, the heating zone can be extremely shortened. What is the length of this heating zone?

There is a close relationship with the ballooning phenomenon caused by high-speed rotation of the yarn due to heating, and ballooning can be suppressed by shortening the heating zone as much as possible. Therefore, in the present invention, the length of the heating zone is preferably 2 m or less, and even in high-speed false twisting processing of 1000 m/min or more, the yarn in the heating zone has a low tension that does not cause the problem of 1 fluff 9 strength reduction. However, stable and uniform high quality crimped yarn can be obtained.

Next, a more detailed explanation will be given using the drawings. FIG. 1 is a schematic diagram showing the configuration of heating roller A-B. Yarn 1 is wound onto the surface of heating roller A and then onto the surface of heating roller B. The winding angle on the surface of the heating roller can be changed as appropriate using the guide 2 and roller. First, for the heating roller A, the contact time t calculated from the diameter and processing speed is set to 0.002 cl≦t≦002d.
It is preferable to set the contact angle θ1 within the range of . Regarding the housing heating roller B, the contact angle θ2≦90 is set to such an extent that the yarn on the roller surface does not change due to heating. The gap S between heating rollers A and B has a structure that allows the roller axes to move in parallel.

It is adjusted using screws, gears, or springs. This gap S is preferably set so that the diameter d of the single yarn constituting the yarn and the diameter of the yarn to which low false twist is applied satisfy the relationship d<S<D.

FIG. 2 shows an embodiment of a false twisting device using heating rollers AB. The yarn 1 is supplied by a supply roller 2, heated and heated in a non-twisted state by a heating roller A, and the false twist is propagated onto a heating roller B by a twisting device B, where it is then heat-set and forcedly cooled by water. After being cooled by the device 5, it is untwisted, passes through a delivery roller 7, and is wound up as a crimped yarn by a winding device 8. In this device, the length L from the gap between the heating rollers A and B to the twisting device 6 is set to within 2 m, which causes problems in the past due to the configuration of the present invention as described above. The heating device used during high-speed crimping becomes longer.

Significant improvements have been made in terms of equipment, such as poor operability. A pair of heating rollers A and B effectively heat the yarn and prevent it from twisting, producing uniform, high-quality crimped yarn at extremely high speeds.

For example, it can be manufactured at 1000 m/+nin or more. Furthermore, the length of the heating zone in which the false-twisted heating yarn runs is extremely shortened.

2 fluffs allow you to maintain low tension during processing.

A crimped yarn can be obtained which prevents defects such as a decrease in strength and has good crimp properties. Furthermore, since the device of the present invention does not use a long heater, it can be made more compact.

EXAMPLES The present invention will be explained in further detail with reference to Examples below.

Example 1 280D-4 taken up at a winding speed of 3200 m/min
An 8F undrawn polyethylene terephthalate yarn was false-twisted in the process shown in FIG. 2 using a triaxial circumscribed friction false-twisting device. The processing conditions are as follows: dust, heating roller A,
Experiments were conducted by changing the winding angle θ of B, lθ2°, the gap S between A and B, and the length of the heating zone.

Machining speed 1200 m/m3. Stretching ratio between n feed roller and heating port 18 Number of false twists 2400 T/rt heating tension
57g Heating rollers A, B (7) Diameter: 200 mm Temperature of heating rollers A, B: 210°C, 215°C Experimental quantities 1 to 5 show the effect of the angle at which the yarn is wound around the heating roller A of the present invention. Experimental quantity 1 had a shortened heating zone, so crimping was possible, but OCT was not possible due to insufficient heating of the yarn.
The value was somewhat low. In Experiment N115, on the other hand, since the heat treatment time in the non-twisted state was long, the heat fixation of the subsequent false twisting was incomplete and the OCT value was somewhat low. Between experiments 6-8
shows the effect of the angle at which the yarn is wound around the heating roller B.

Experimental amount 6 is for the case where no winding is done.

This method instantly heat-sets the false twist of the yarn heated by heating roller A without lowering the temperature by heating roller B.
Although it had a certain degree of heat fixation effect, fuzz was generated, which was not desirable. Experimental amount 9 indicates a case where the gap S between the heating rollers A and B is approximately the same as the diameter of the heating yarn. Experimental amount 1
0 indicates the effect of heating zone length. Experimental amount 10 had a short heating zone and stable processing was possible. Experiment m12 is a comparative example of the present invention using plate heater 3. Using C1m.

The length of the heating zone was 4.5 m, and the running yarn vibrated abnormally, making it impossible to process the yarn at all.

Example 2 Nylon 6 was melt-spun and subsequently stretched and false-twisted using the apparatus shown in FIG. 2 without being wound up.

It was supplied to heating roller A under conditions of a spinning speed of 800 m/min and a draw ratio of 35. The false twisting conditions were as follows, and the experiment was conducted by changing the temperatures of heating rollers A and B. The false twisted crimped yarn obtained was 4801D-30.7.

False twisting speed 2800 m/min
Number of false twists: 1220T/M Heating tension: 110g Heating roller diameter: 20mm Winding angle of heating roller A: 27o0 Winding angle of heating roller B: 60° Gap SO, 15mm Heating zone: 0.8 m Table 2 Experiment m1 is Since the temperature of heating roller A was higher than that of heating roller B, processing was possible although the crimp characteristics were inferior. Experimental direction 6 has the best temperature balance between heating rollers A and B, and is therefore preferable. In Experiment No. 4, the temperature of the heating roller A was too low, so the crimp characteristics tended to be poor. If we take the optimum value of the present invention.

In high-speed processing directly connected to spinning, a crimped yarn was obtained that was comparable to the normal false twisting process of the comparative example.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing the configuration of a heating roller of the present invention. FIG. 2 shows an embodiment of the entire process of false twisting. 1: Supply yarn 2: Feed roller 6: Yarn path guide 4: Yarn path guide 5: Forced cooling device 6: Twisting device 7: Delivery roller 8: Winding device A: Heating roller B: Heating roller S: Heating Roller gap L: length of heating zone

Claims (1)

[Claims] (1) A false-twisting processing method in which a thermoplastic synthetic fiber yarn is false-twisted and heat-set using at least two heating rollers,
The substantially untwisted yarn is heated with a heating roller A to raise its temperature,
A false-twisting method characterized by using a pair of heating rollers that then thermally fix the false twist with a heating roller B while imparting false twist to the heated yarn without lowering its temperature. (2) A relational expression is established in which the time t (unit: seconds) of the yarn in contact with the heating roller A is 0.002d≦t≦0.02d with respect to the fineness d (unit: denier) of the single yarn constituting the yarn. A false twisting method according to claim (1), which satisfies the above. (3) The angle at which the heated yarn contacts the heating roller B is 90°
A false twisting method according to claim (1) or (2), characterized in that: (4) The false twisting method according to claim (1), characterized in that the temperature of heating roller B is made higher than the temperature of heating roller A. (5) Claim No. 1 (1) characterized in that the supplied thermoplastic synthetic fiber yarn is guided to the heating roller A while being stretched.
) or the false twisting method described in (4). (6) The gap S between the heating rollers A and B is set so that the relationship between the diameter d of the single yarn constituting the yarn and the diameter D of the false twisted yarn satisfies the formula d<S<D. A false twisting method according to claim (1), characterized in that: (7) In an apparatus for false twisting thermoplastic synthetic fiber yarn, a yarn supplying means, a pair of at least two heating rollers, a twisting device, a delivery means, and a winding device are provided in this order from the upstream side, A false-twisting device characterized by comprising an adjustment mechanism that allows adjustment of the mutual gap between the pair of heating rollers A and B consisting of at least two. (8) The false twisting apparatus according to claim (7), further comprising a cooling device for forcibly cooling the heated yarn immediately after the heating roller B in a water bath or by attaching water to the heated yarn. (9) Claim (7) characterized in that the length of the heating zone from the position where a gap is formed between heating rollers A and heating rollers B to the twisting device is within 2 m.
False twisting device described in Section 1.