JPS6363650B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an efficient method for producing spun yarn, and more particularly to a binding spinning method in which a fleece of short fibers that have been opened and widened is bound using an air vortex. Spun yarn is made by arranging staple fibers, drafting them, twisting them and converging them to give them a strong enough for practical use and a highly flexible texture. In the conventional manufacturing process of spun yarn, especially in the spinning process, twisting becomes a problem and increasing the spinning speed is extremely difficult. Even with open-end spinning, in which fiber fleece is twisted and converged again, the limit is a spinning speed that is more than twice that of ring spinning. Furthermore, bonded or fused spun yarns have been proposed as a new method for producing spun yarns, but since this has a yarn structure in which the fibers that form the yarn are adhesively restrained, the yarn becomes stiff and the weaving properties are reduced. However, the texture of the resulting product also has the disadvantage of being rough and hardened, and its use is limited to special fields, so at present it is hardly put to practical use. With the aim of increasing productivity and providing the same level of versatility as conventionally spun yarns, we have developed a new method based on a new spinning principle.
An innovative bundled spinning method was developed as a method for obtaining high-speed spinning of m/min and large packages. In other words, to explain the binding spinning method in principle, fiber bundles made of staple fibers are drafted and distributed, and then fed to the nip in the form of an open sleeve, which can be used to create fibers such as aprons that are capable of twisting. While the fleece is being transferred by the transfer means, a temporary twist is imparted to the fleece by the effect of the air vortex, and the twist is propagated to the vicinity of the nip point of the nip roller in the feeding area, causing the spread and distribution of the fleece to take place. , the fleece located near both ends produces unconstrained fleece fibers that are not added at the nip point. In this state, immediately before the temporary twisting fluid nozzle, the fleece fiber bundle becomes the temporary twisted main fiber bundle which has undergone the normal temporary twisting action, with a number of twists significantly smaller than the number of temporary twists, In addition, some of the fleece fibers are mainly twisted near the surface of the temporarily twisted fiber bundle. When the fiber bundle passes through the temporary twist fluid nozzle in such a state and the temporary twist release action is applied, the main fiber bundle becomes substantially untwisted or in a similar state, and is twisted with a small number of twists. The fleece fibers that had been used have been over-raveled,
A strong winding action is applied to the main fiber bundle in the unraveling direction, and as a result, a bound spun yarn having a structure in which the entire main fiber bundle is bound is obtained. As mentioned above, the characteristic of this spun yarn is that short fibers are wound around a substantially twist-free central fiber bundle to form a spun yarn. This largely depends on whether or not it exists. Therefore, control of the wound fibers and the non-constrained fleece fibers at both ends during spinning is an extremely important factor in terms of yarn quality. The present invention was obtained as a result of repeated improvements to the control means for the above-mentioned non-end bound fleece fibers, and it is possible to obtain wrapped fibers more easily and accurately than the conventional method, and to efficiently produce bound spun yarn. The aim is to provide a method for doing so. That is, in the method of the present invention, one fluid temporary twisting nozzle is provided immediately after the knitting roller at the most downstream side of the draft area, and the drafted short fiber fleece is temporarily twisted under a linear yarn path to form a bundled spun yarn. When manufacturing, the short fiber fleece is brought into bending contact with the top roller or bottom roller of the nip roller at a contact arc center angle within the range of π/6 to π/2 radians after the nip point, and the twist imparted by the temporary twist nozzle is removed. Substantially unrestricted fibers are generated at both ends of the fleece by twisting it up substantially above the draft knit roller, and then the temporarily twisted fiber bundle that has been subjected to the temporary twisting action and the unrestrained fibers are separated. This is a method for producing bound spun yarn, which is characterized in that the yarn is transferred and supplied to a temporary fluid twist nozzle. Hereinafter, the binding spinning method of the present invention will be explained in more detail using the drawings. FIG. 1 shows an embodiment of the present invention, and FIG. 2 is a plan view of the front roller section of FIG. 1, with the top roller not shown in order to clarify the attached state. The method for producing a bundled spun yarn of the present invention includes providing one fluid temporary twisting nozzle immediately after the knitting roller at the most downstream side of the draft area, and using the temporary twisting nozzle to move the drafted short fiber fleece along a straight yarn path. This method involves temporarily twisting the yarn at the bottom to produce a bundled spun yarn.
Here, as shown in Fig. 1, the linear thread path extends from the front knit rollers 2, 2' located at the most downstream position in the draft area to the delivery rollers 4, 4' in the temporary twist area. This means that the thread path is substantially straight between. The fleece 1, which is distributed by cutting or drafting and is spread, is placed around the circumference of the front rollers 2 and 2', which are the nip rollers located at the most downstream position in the draft area. radius, θ: center angle of contact arc (radians)) and is guided to the fluid nozzle 3 with a temporary twist. As mentioned above, the fluid nozzle causes the yarn path to be in a straight line throughout the entire nipping area, so as shown in Fig. 2, the yarn rises up to the nip points at the top and bottom of the front roller and temporarily reaches the top of the nip roller. The twist propagates, producing unconstrained fleece fibers A that are not added at the nip point position. In the embodiment shown in the drawings, such unrestrained fleece fibers A rotate and move along the surface of the bottom roller, and form a temporarily twisted fiber bundle (main fiber bundle) which is subjected to a temporary twisting action in the center. ) and gradually become entangled in it. As a result, the fleece fiber bundle immediately before the temporary twisting fluid nozzle has a twist number smaller than the number of temporary twisting fibers and is mainly the temporary twisted fiber bundle which has undergone the normal temporary twisting action. Some of the fleece fibers are twisted together near the surface of the fabric. After this, the principle of the knot spinning method described above is followed. The spun yarn Y is pulled out by delivery rollers 4, 4', and a package 5 is formed by a winder. One of the major features of the method of the present invention is that the fleece discharged from the front roller is directly introduced into one temporary fluid nozzle provided immediately after the nip roller without using any other conveying means. The advantage is that tied spun yarn can be produced. The conventional method of introducing the fleece into the temporary twist nozzle is to prevent the fleece from wrapping around the front roller, maintain the parallelism of the fleece, prevent unrestrained fibers from scattering, and increase binding strength to produce strong spun yarn. , a method using an aspirator jet using compressible fluid to suck up the fleece discharged from the front roller and guide it to the nozzle, and a method for creating upper and lower aprons with openings large enough to prevent the propagation of temporary twists from reaching the nip point. A method such as feeding the fleece to the conveying nozzle by sandwiching the fleece between them was used, but the former method has the following problems: to successfully generate unrestrained fleece fibers, and to twist the fleece fibers into the main fiber bundle with a small number of twists. It is difficult to control and it is difficult to obtain a preferable bundled spun yarn, and the latter is not suitable for high-speed processing due to problems such as the apron being easily cut. The inventors of the present invention can sufficiently achieve the above-mentioned objective effect by temporarily twisting the fleece discharged from the front roller in contact with the rollers in γ and θ as in the present invention.
Furthermore, it has been found that since the contact arcs of γ and θ act as restraining friction bodies, the conjugation between the single fibers due to the addition of fibers increases, and the release torque increases in the release region, which has the effect of strengthening the cohesive force. Note that this θ depends on the performance of the fluid nozzle and the spinning speed, but it is necessary for the fleece to propagate close to the roller nip point (if it does not propagate, part of the fleece will wrap around the roller, causing an undesirable phenomenon). ), and furthermore, from the viewpoint of preferable control of unrestricted fibers, it is necessary to set it to π/6 to π/2 radian. Regarding the method of the present invention, in the explanation based on the above drawings, the contact arc is placed on the bottom roller side, but even if the contact arc is provided on the top roller side, it can be carried out without causing inconveniences such as fiber scattering or falling off. It is possible. As described above, according to the present invention, no special fiber transfer means is required between the front roller and the fluid temporary nozzle, so the overall device configuration is extremely compact and simplified, and operability is improved and high speed is achieved. It is possible to produce stable, high-quality spun yarn. The temporary twist nozzle used in the method of the present invention is
It is preferable to have suction performance within a range that does not interfere with the implementation of the present invention, and by doing so,
This allows the unrestricted fibers and the bound fiber bundle to be integrated more smoothly. Suitable raw materials for production by the method of the present invention include natural fibers such as cotton, wool, and silk, synthetic fibers such as polyester and polyamide, semi-synthetic fibers, regenerated fibers, metal fibers, and glass fibers. Furthermore, it is an extremely excellent spinning method that does not have any restrictions on the spinning count, from extremely fine counts of about Nm1/200 to extremely thick counts of about Nm1/4.
Excellent spinnability is exhibited within the range of Nm 1/60 to 1/200. Example Average fiber length 120 mm (variable cut) made by cutting polyester tow with a single fiber denier of 1.3 d.
Two bovina rovings made of slivers were fed in parallel to a three-wire hollow roller draft section, and the drafted staple bundle was given a temporary twist with an air nozzle, and then passed through a delivery roller and wound around cheese. At this time, the yarn strength and spinning conditions were investigated by changing the angle θ shown in FIG. 1, and the results are shown in Table 1. Spinning conditions Total draft magnification: 105 times Spinning speed (delivery): 100 m/min Front/delivery overfeed rate: 6% Spinning yarn count: Nm100 Nozzle air pressure: 3.0 Kg/cm ²

[Table] As is clear from Table 1, by setting the angle θ to 30° or more, the yarn strength improves and the spinning becomes stable, but if it becomes larger than 90°, the spinning becomes unstable, which is undesirable. Ta.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the method of the present invention, and FIG. 2 is a plan view of the front roller section in FIG. 1. 1: fleece, 2, 2': front knit roller, 3: fluid temporary twist nozzle, 4, 4': delivery roller, 5: winding package, A: unrestrained fleece fiber, Y: spun yarn.

Claims (1)

[Claims] 1. One fluid temporary twisting nozzle is installed immediately after the knit roller at the most downstream side of the draft area, and the drafted short fiber fleece is temporarily twisted under a straight yarn path to produce a bound spun yarn. The fleece is brought into bending contact with the top roller or bottom roller of the nip roller within a contact arc center angle range of π/6 to π/2 radians from the nip point, and the twist imparted by the temporary twist nozzle is substantially transferred onto the draft nip roller. substantially generating unrestrained fibers at both ends of the fleece by twisting the fibers up to the point where the fibers are twisted, and then transferring and supplying the temporarily twisted fiber bundle that has been subjected to the temporary twisting action and the unconstrained fibers to a fluid temporary twisting nozzle. A method for producing bound spun yarn characterized by: