JPH0224932B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a yarn false twisting method for bulking a multifilament yarn.

Yarn false twisting method for obtaining a bulky textured yarn by passing the yarn pulled out from the yarn feeding package through a heater and introducing it into a false twisting device, and fixing the twist formed on the yarn by the false twisting device with the heat of the heater. Although this method is well known, the bulky textured yarn obtained by this method has quite a bit of fuzz, and many measures have been attempted to prevent this fuzz.

The present invention provides one effective method for combating these fluffs.

While researching the cause of the occurrence of fuzz and attempting various experiments, the present inventor found that a large amount of fuzz occurs when the yarn is not sufficiently untwisted immediately after leaving the false twisting device and some twist remains. I discovered a fact. In addition, the more twist remains as described above, the more fuzz is generated, and conversely, when no twist remains or when twists in the opposite direction are formed due to over-untwisting, the generation of fuzz is significantly reduced. It was also possible to confirm this, and this enabled us to arrive at the present invention. Conventionally, it was assumed that the yarn coming out of the above false-twisting device would naturally untwist due to the torque of the yarn itself, so to speak, and leave it to the passive untwisting of the yarn itself. It was inevitable that some twist remained in the yarn.

Therefore, the present invention proposes to actively untwist the yarn immediately after it comes out of the false twisting device in order to prevent the twist from remaining.

Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows the entire false twisting machine, in which the yarn Y is pulled out from the yarn supply package P1 by the first feed roller 1, passes upward through the first heater 2, and is bent by the guide pins 3 and 4. After that, it travels in a substantially horizontal direction, passes through a balloon control plate 5, and is introduced into a false twisting device 6. The twist formed on the yarn Y by the false twisting device 6 propagates through the balloon control plate 5 and the first heater 2 to the first feed roller 1, where it is thermally fixed. False twisting device 6
The untwisted yarn Y is bent downward by a guide roller 7, passes through a second feed roller 8, a second heater 9, and a third feed roller 10 in order to become a sufficiently bulky yarn, and is then fed to a friction yarn. It is wound onto a winding package P2 which is rotationally driven by rollers 11.

The false twisting device 6 and guide rollers 7 are shown in FIG.

The false twisting device 6 has two endless belts B1 and B2.
are wound between the driving pulley 12 and the driven pulley 13, and both belts B1 and B2 are crossed in an X shape, and the thread Y is nipped between the crossing surfaces of the belts B1 and B2. Due to the rotation, both belts B1 and B2 run in the direction to send out the thread Y, and at the same time, a component of the running force causes the thread Y to be sent out.
Add twist to. The twists formed in the yarn Y in this way include an S twist and a Z twist, but these are the second twists.
In the figure, switching is performed by mutually exchanging the positions of belts B1 and B2 with respect to yarn Y and reversing the running directions of belts B1 and B2, respectively. The false twisting device 6 shown in FIG. 2 will be explained below assuming that it forms a Z twist on the upstream side of the yarn Y.

The guide roller 7 is a rotary roller that freely rotates around a shaft 14, and has a V-shaped guide groove 16 on the outer periphery of the roller with slopes 15a and 15b on both sides.
is formed. 17 is a yarn guide provided between the guide roller 7 and the second feed roller 8;
The thread Y is attached to the guide roller 7 in the side view shown in FIG.
However, as shown in FIG. 2, when viewed from above or from the front, the thread guide 17 guides the thread so that it travels along the same straight line as before being introduced into the false twisting device 6. ing. The guide roller 7 has a plane orthogonal to the axis 14 at a certain angle θ with respect to the yarn Y.
As the thread Y passes through the guide roller 7, it first contacts the left slope 15a in FIG. 2, then contacts the bottom surface 18 of the groove, and then contacts the other slope 15b. and separates from the guide roller 7. An arrow 19 indicates the direction in which the guide roller 7 is rotated by contact with the yarn Y at this time.

The function of the guide roller 7 will now be explained with reference to FIG.

The point at which the yarn Y first contacts the guide roller 7 is the point 20 on one slope 15a as described above, and the force acting on the yarn Y due to the rotation of the guide roller 7 is It acts in the tangential direction of the circle 21 on the circumference. If this force is shown by an arrow F, the above force is divided into a force F1 acting in the sending direction of the yarn Y and a force F2 acting in a direction perpendicular to the yarn Y, and the force F2 in the perpendicular direction is applied to the slope 15a. It acts to pull up the yarn Y, giving a rotational force to the yarn Y, and as a result, the yarn Y is twisted in the S twist direction from the point 20 to the upstream side. The above force F2 is point 20
It acts continuously on the yarn Y between the point 22 where the yarn Y contacts the bottom surface 18, and the S twist formed on the yarn Y propagates upstream, and the false twisting device 6
The Z twist remaining in the yarn Y that exits cancels each other out.

The yarn Y further moves from the bottom surface 18 to the other slope 15b and is subjected to the same twisting action as described above, but the twist formed thereby is also an S twist. Since this twist propagates from the guide roller 7 to the downstream side along the yarn Y, experiments have shown that it does not have much influence on the generation of fuzz in the yarn Y. Therefore, the yarn guide 17 in FIG. Move to the left and thread Y
is run as shown by the dashed line 23, and the slope 1 is
It is also possible to avoid contact with 5b. Yarn Y again
are both belts B1 and B before and after the false twisting device 6.
It is preferable to run on a straight line parallel to the two intersecting planes. This is to prevent the tension difference between the yarns before and after the false twisting device 6 from increasing due to the bending of the yarn Y, and to prevent yarn breakage due to the tension difference, and the yarn Y comes into contact with the edges of the belts B1 and B2. This is to prevent damage from occurring.

The active untwisting action of the yarn Y by the guide roller 7 described above depends on the diameter, material, and inclination angle θ of the guide roller 7, the shape and angle of the slopes 15a and 15b, the thickness, yarn quality, and running speed of the yarn Y. However, according to experiments, generally speaking, the farther the point 20 where the yarn Y first contacts the slope 15a is from the bottom surface 18, and the inclination angle of the guide roller 7. It was confirmed that it is almost effective when θ is large. Guide groove 16
may have a U-shape or other shapes other than V-shape, but it is one that can exert an untwisting effect on the yarn when it comes into contact with the yarn Y, and the yarn path does not change much within the groove 16. It is necessary. Further, the guide roller 7 can be fixed or actively rotated, and a plurality of guide rollers 7 may be provided. As mentioned above, there is no problem even if the number of twists formed on the yarn Y by the guide roller 7 is greater than the number of twists remaining in the yarn Y leaving the false twisting device 6, that is, over-untwisting occurs. That's right.

Note that when the twist formed in the yarn Y on the upstream side of the device 6 by the false twisting device 6 is an S twist, the inclination θ of the guide roller 7 is reversed so that the yarn Y first contacts the slope 15b. Just do it like this.

According to the method described above, the twist formed on the upstream side by the guide roller 7 cancels out the twist remaining in the yarn Y leaving the false twisting device 6,
The remaining twist can be reduced to prevent the occurrence of fuzz.

The guide roller 7 is only one example of means for preventing twist remaining in the present invention, and the false twisting device 6
Any method that actively untwists the yarn Y that comes out of the yarn Y is included in the present invention. Regarding the false twisting device 6,
For example, a friction type in which the thread Y is brought into contact with a plurality of rotating disks, or various other types may be used.

As explained above, according to the present invention, by actively untwisting the twist remaining in the yarn exiting the false twisting device, it is possible to reduce the fuzz generated in the processed yarn, resulting in a high quality It became possible to obtain bulky textured yarn.

[Brief explanation of drawings]

FIG. 1 is a diagram schematically showing the entire false twisting machine to which the present invention is applied, FIG. 2 is a diagram showing details of the false twisting device and the guide roller, and FIG. 3 is a diagram showing the guide roller in FIG. FIG. 2...First heater, 6...False twisting device, P1...
Yarn supply package, Y... yarn.

Claims (1)

[Claims] 1. Yarn false-twisting method for obtaining a bulky textured yarn by passing the yarn pulled out from the yarn supply package through a heater and then introducing it into a false-twisting device, and fixing the twist formed on the yarn by the false-twisting device in the heater. A yarn false-twisting method, characterized in that the yarn is actively untwisted immediately after leaving the false-twisting device.