JPS6246650B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a non-twisted spun yarn and a false twisting nozzle.

More specifically, a short fiber bundle such as a roving, a sliver, or a stretched tow is introduced into a false twisting nozzle, either alone or in combination with a continuous yarn.
The present invention relates to a novel method of winding fluff around the single fibers constituting the short fiber bundle or the single fibers constituting the continuous yarn to form a continuous yarn, and a false twisting nozzle used in the method.

Conventionally, various methods have been proposed for producing yarn with a spun yarn texture with high efficiency by subjecting short fiber bundles to fluid treatment. etc., and it was difficult to sufficiently approximate conventional spun yarn in terms of quality, especially uniformity.

The inventors of the present invention conducted extensive research into how the above-mentioned quality defects occur, and as a result, they found that the cause lies in the false-twisting nozzle, and arrived at the present invention. In other words, in the conventional false-twisting nozzle, a fluid injection hole is provided to the fiber bundle introduction path so as to inject fluid toward the exit side of the fiber bundle introduction path, so that the fiber bundle before and after the false-twisting nozzle is The tension experienced by the front part was either greater in the front part or almost equal in both parts. For this reason, the untwisting point (the point at which the false twist is untwisted) is shifted to the rear of the false twisting nozzle, so there is less fluff entrapped during untwisting, and sufficient binding properties cannot be obtained. .

On the other hand, in the upstream of the false twisting nozzle, the fiber bundle introduced into the false twisting nozzle undergoes no twisting except for false twisting.
There is almost no entanglement between the single fibers that make up the fiber bundle, and therefore, after untwisting, the binding force is very weak, and each single fiber is in an unstable state where it easily slides even with the slightest force. It is in. Therefore, when the fiber bundle passes through the false twisting nozzle, if the fluff is not wrapped sufficiently, some of the single fibers making up the fiber bundle will be affected by the jet fluid of the false twisting nozzle and the tension of the yarn. The fiber bundles easily slide and are transported faster than other fiber bundles, resulting in slack or loops, or the free ends of the single fibers become entangled in a lump, forming a slab or nep, resulting in a uniformity of the yarn. It was seriously harmful to sexuality. The present invention aims to improve the defects of the conventional false twisting nozzle as described above and to provide a non-twisted spun yarn having excellent uniformity and cohesiveness.

That is, the present invention provides a method of introducing a fiber bundle consisting of discontinuous fibers or having discontinuous fibers as a main component into a non-twisted spun yarn by introducing the fiber bundle into a false twisting nozzle. The side diameter is smaller than the inlet side diameter, and the fluid injection hole is perpendicular to the central axis of the fiber bundle introduction path and does not intersect with the central axis,
By making the fibers eccentric in one direction, the jetting fluid of the false twisting nozzle has a propulsive force in the direction opposite to the traveling direction of the fiber bundle, thereby imparting conjugation to the single fibers constituting the fiber bundle. The false twisting nozzle used in such a method is a method for producing a non-twisted spun yarn, which is characterized by a method of producing a non-twisted spun yarn. The central axis does not intersect with the central axis of the fiber bundle introducing path and is eccentric in one direction to apply a turning force, and the outlet side diameter of the fiber bundle introducing path and the inlet side diameter where the fluid injection hole is opened. A fiber bundle is used that simultaneously satisfies the following condition: the area ratio of the cross section perpendicular to the central axis of the fiber bundle introducing path is exit side cross section/inlet side cross section ≦0.7.

The present invention will be explained in detail below.

The fiber bundle made of discontinuous fibers used in the method of the present invention is a fiber bundle made of fibers having a finite length, and is made of staple fibers or a sliver obtained by cutting tow. It may be hot.

Further, in the present invention, a fiber bundle partially mixed with continuous yarn may be used.

This will be explained below using figures.

FIG. 1 is a process diagram showing one embodiment of the present invention.

In FIG. 1, a fiber bundle 1 is taken off from a supply roller 2 in a twisted manner by a take-off fluid nozzle 3 which performs both a suction action and a swirling action. Subsequently, the fiber bundle is introduced into a false twisting treatment nozzle 5, and the ends of the single fibers constituting the fiber bundle are wrapped around the fiber bundle and tied together to form a thread 6. Then the yarn 6
is transferred as a non-twisted spun yarn 6 from a delivery roller 7 and wound onto a package 9 via a winding roller 8.

Figure 2A shows the take-up fluid nozzle 3 shown in Figure 1.
FIG. 2B is a side view of a piece having a fluid injection hole, which is a part of the piece, and FIG.

In FIG. 2, the fluid injection hole 10 forms an inclination angle a with respect to the fiber bundle introduction hole 11.
The fluid is injected toward the exit of the fiber bundle, and a thrust is applied in the direction of movement of the fiber bundle. Further, the central axis of the fluid injection hole is eccentric in one direction with respect to the central axis of the fiber bundle introducing hole, so that a winding force is applied to the fiber bundle. With this configuration, short fiber bundles with low conjugation properties can be stably taken off from the supply roller even at high speeds without single fibers being wound around the rollers.

3A is a sectional view of a plane including the central axis of the fiber bundle introduction path of the false twisting nozzle 5 used in the method of the present invention shown in FIG. 1, and FIG. 3B is shown in FIG. 3A. It is a sectional view showing a cross section on the line B-B', and shows a fluid supply pipe 15, a fluid transfer pipe 14, and a fluid injection hole 1.
3. It consists of a fiber bundle introduction path 12. The fluid injection hole 13 of the false twisting nozzle 5 is connected to the fiber bundle introduction path 12.
The opening is perpendicular to the fluid injection hole 1.
The central axis of the fiber bundle introduction path 12 is eccentric in one direction with respect to the central axis of the fiber bundle introduction path 12, so that a turning force can be applied. If the central axes of these two are not eccentric in one direction, but also in the crossing or opposite direction, a swirling vortex will not be generated in the fiber bundle introduction path 12, and the fiber bundle 1 will not be disturbed, making it difficult to wind the fluff. Become,
This results in a yarn with weak binding of single fibers, and the target yarn of the present invention cannot be obtained.

Further, it is preferable that the central axis of the fluid injection hole is perpendicular to the central axis of the fiber bundle introduction path, whereby swirling force can be applied efficiently and the nozzle can be easily worked.

Here, regarding the arrangement of the fluid injection holes 13, the third
As shown in the figure, it is convenient to provide a pair near the exit side of the fiber bundle introduction path and at symmetrical positions with respect to the fiber bundle introduction path 12 from the standpoint of fluff winding performance and nozzle manufacturing. As long as the cross section of 12 is tangential to one side, the number of fluid injection holes 12 may be one or three or more, and furthermore, they may be distributed in the length direction of the fiber bundle introduction path. In addition, the dimensions of the fiber bundle introduction path 12 and the fluid injection hole 13 may be appropriately selected according to the denier and cross-sectional shape of the single fibers constituting the fiber bundle 1, or the total denier of the yarn to be obtained. good. Further, the present false twisting nozzle 5 may be of a one-piece type, or may be of a slit type or a half-split type with appropriate slits provided for ease of handling.

Further, the diameter of the exit side 12b of the fiber bundle introduction path 12 is reduced to a small diameter so as to have a propulsive force in a direction opposite to the traveling direction of the fiber bundle. That is, the area ratio of the diameter of the exit side 12b and the diameter of the inlet side 12a of the fiber bundle introduction path 12 in a cross section perpendicular to the central axis of the fiber bundle introduction path is: exit side cross-sectional area/inlet side cross-sectional area≦0.7. It is necessary to reduce the diameter on the exit side so that

If the above-mentioned area ratio exceeds 0.7, the driving force of the fluid jet in the direction opposite to the traveling direction of the fiber bundle decreases, resulting in poor nep and handling properties as shown in Fig. 4. There is no difference between this method and the method described above, and the object of the present invention cannot be achieved.

Here, Figure 4 is a diagram illustrating the relationship between the number of neps and handleability of the yarn obtained with respect to the cross-sectional area ratio (cross-sectional area on the exit side/cross-sectional area on the inlet side), and the number of neps is determined by a Worcester spot measuring device. Measured values and handling properties were evaluated by the number of yarn breaks during twisting using a ring twisting machine. 〇 indicates the number of yarn breaks 0.02 times/10 spindles per hour, △ indicates the level of 〃 ≒0.05 〃 × indicates the level of 〃 0.1〃 It is something.

Since the method of the present invention has the above-described configuration, almost no tension is applied to the fiber bundles in a false-twisted state treated by the method of the present invention, and mainly,
Since tension is applied to the yarn material downstream of the false twisting nozzle 5, the advantageous effect is obtained that the false twist is dammed up within the false twisting nozzle and an untwisting point occurs within the nozzle. That is, according to the false twisting nozzle 5 used in the method of the present invention, the diameter of the outlet side 12b of the fiber bundle introduction path of the false twisting nozzle is narrowed down, so that the fiber bundle 1 is It will receive a propulsive force in the opposite direction. Therefore, the external force on the fiber bundle before being introduced into the false twisting treatment nozzle 5 can be reduced, and this effect can be obtained. As a result, the relative rotational speed difference between the yarn after untwisting and the swirling flow of the nozzle becomes large, which also causes the fluff ends to flow in the opposite direction to the false twisting direction at the front of untwisting. When the twist is untwisted, the fluff ends are effectively wrapped around the fiber bundle mainly in the direction opposite to the false twisting direction and are tightly bound, eliminating the problems of slubs and neps that were caused by conventional weak binding properties. A yarn with improved width and uniform appearance can be obtained. Furthermore, the false twisting nozzle 5 of the present invention has almost no thrust toward the downstream side, and tension is applied to the yarn on the downstream side of the false twisting nozzle 5. It has a more uniform appearance with far fewer sags and loops than the conventional one.

This function and effect of the present invention can be maximized.

Note that the pressure of the fluid jetted from the take-up fluid nozzle 3 and the pressure of the fluid jetted from the entangling treatment nozzle 5 shown in FIG.
The overfeed ratio of the supply roller 2 to the delivery roller 7 and the like are also important conditions for obtaining high quality. That is, the take-up fluid nozzle pressure needs to be set so that the fiber bundle does not wrap around the supply roller 2, and a suitable value is about 2 to 5 kg/cm ³ . Also,
The nozzle pressure for the entangling treatment needs to impart sufficient conjugation to the fiber bundle, and is suitably between 2 and 5 kg/cm ³ . It is desirable that these two nozzle pressures be as small as possible within the necessary range. Delivery roller 7
The appropriate overfeed rate of the supply roller 2 is 3 to 10%, and when the number of fibers constituting the fiber bundle is large, a low overfeed is good, and conversely, when the number of fibers constituting the fiber bundle is small, a high overfeed is good. Further, it is preferable that the direction of rotation of the take-up nozzle is opposite to the direction of rotation of the false-twisting treatment nozzle.

In addition, the above-mentioned take-up fluid nozzle pressure, entangling treatment nozzle pressure, and overfeed rate are each related to each other, and the single fiber denier short fiber length of the supplied fiber bundle 1, the cross-sectional shape, the type of oil agent, the humidity of the atmosphere, Appropriate conditions are selected depending on the denier of the yarn material, processing speed, etc.

It goes without saying that the untwisted spun yarn obtained by the method of the present invention can be additionally twisted and used for conventional twisted spun yarns.

The present invention will be explained below with reference to Examples.

Example 1 A non-twisted spun yarn was spun in the process shown in FIG.

For the hand-held fluid nozzle 3, a piece 4 with an inclination angle a of 45 degrees as shown in FIG. Pressurized air of 16 to 4 kg/cm ³ was supplied.

The false twisting nozzle 5 has two fluid injection holes 1.1φ x 2 in diameter as shown in FIG.
5 kg/cm ³ of compressed air was supplied from the fluid supply pipe 15 using a fluid supply pipe 15.

Under the above nozzle conditions, using a polyester tension-cut sliver with a total denier of 270, an average single yarn denier of 2.5, and an average fiber length of 400 mm as the supply fiber bundle 1, the overfeed ratio of the supply roller 2 to the delivery roller 7 was set to 85%. The untwisted spun yarn was spun under the condition that the surface speed of the supply roller 2 was 200 m/min. There were almost no interrupted yarns or troubles during spinning, and when the obtained yarn was measured using an evenness tester, yarn unevenness μ% was 10.8%, and NEP was 3.
A product was obtained that had a length of 125 m and a very uniform appearance with few loops, sagging, and fuzz. In addition, the conjugation property was strong enough to withstand the weaving and preparation steps.

[Brief explanation of the drawing]

FIG. 1 is a process diagram showing one embodiment of the present invention. Figure 2 is a diagram showing an example of the piece of the drawing fluid nozzle shown in Figure 1, where A is a side view and B is a side view A.
A sectional view taken along the −A′ line is shown. FIG. 3 is a diagram showing an example of the false twisting nozzle shown in FIG. 1, in which A shows a side view and B shows a sectional view taken along the line B-B' of the side view. FIG. 4 is a diagram illustrating the relationship between the number of neps of the obtained yarn and the handleability with respect to the ratio of the cross-sectional area on the exit side and the cross-sectional area on the inlet side of the false twisting nozzle. 1... Fiber bundle, 5... False twisting nozzle, 6...
Non-twisted spun yarn, 12...Fiber bundle introduction path, 13...Fluid injection hole.

Claims (1)

[Scope of Claims] 1. In a method of introducing a fiber bundle consisting of discontinuous fibers or having discontinuous fibers as a main component into a false-twisting nozzle to form a non-twisted spun yarn, the introduction of the fiber bundle into the false-twisting nozzle The outlet side diameter of the passageway is smaller than the inlet side diameter,
By arranging the fluid injection hole in a direction perpendicular to the central axis of the fiber bundle introducing path, without intersecting the central axis, and eccentrically in one direction, the jetting fluid of the false twisting treatment nozzle can be applied to the fiber bundle. A method for producing a non-twisted spun yarn, characterized in that a propulsion force is applied in a direction opposite to the traveling direction to impart binding properties to the single fibers constituting the fiber bundle. 2. In a false twisting nozzle that consists of discontinuous fibers or fiber bundles containing discontinuous fibers as a main component to form a non-twisted spun yarn (a) A fluid jet opening perpendicular to the central axis of the fiber bundle introduction path. The central axis of the hole does not intersect with the central axis of the fiber bundle introduction path and is eccentric in one direction to apply a swirling force (b) The exit side diameter of the fiber bundle introduction path and the fluid injection hole The area ratio of the cross section perpendicular to the central axis of the fiber bundle introduction path to the diameter of the inlet side where the fiber bundle introduction path is open satisfies the following: cross-sectional area of the outlet side/cross-sectional area of the inlet side≦0.7. Twisting processing nozzle.