CZ41395A3 - Enhanced process of spindleless spinning of yarn and apparatus for making the same - Google Patents

Abstract

A method of fibre assembly for open-end spinning of yarn (1) by a twisting unit (8) is disclosed which comprises delivering air entrained fibres into a defined assembly zone (4), maintaining a circumferential air flow around the air entrained fibres in the assembly zone, said circumferential air flow being of a pressure to radially compress the fibre assembly in the assembly zone (4) and being in the required direction of twist of the finished yarn as governed by the twisting unit (8), withdrawing air from said assembly zone in the axial direction of entry of the fibres and withdrawing the assembly of fibres formed in the assembly zone in the opposite axial direction to pass to the twisting unit (8). Apparatus for performing the invention is also disclosed.

Description

An improved beszelenen method for performing this method

Technical field

The present invention relates to open-end spinning of textile yarns with a high production rate and improved quality, wherein the staple fibers are transferred as individual fibers by air flow from the fiber-releasing device to the fiber spinning zone, where the fibers are assembled into a freely rotating tail and subsequently twisted in that they create at the same time.

BACKGROUND OF THE INVENTION

The development of friction spinning for general use in the production of textile yarns has hitherto been delayed by the necessary need to create a fiber assembly while applying twisting in the same operating phase. This concept of friction spinning typically creates a spiral-guided fiber structure rather than a straight and parallel guided fiber. There is considerable slippage between the fiber assembly and the friction surfaces, due to the wide gap between the friction surfaces, which is necessary for both functions to form the fiber assembly and twist it. The formation of the fiber assembly spiral and the imperfection of the positive control of the twisting effect of the fiber assembly results in an unstable yarn with varying twisting ratios.

Similar problems are encountered in the case of yarn produced by other methods of friction spinning, even if the phases of the formation of the fiber system and the twisting are separated, since such changes in the manufacturing processes cannot ensure that the rotation of the formed yarn is maintained. conditions of existence of the free end of the tip of its tail and that such rotation is in permanent synchronization with the twisted tangling applied by the friction surfaces. The same problems of uneven yarn and irregular twisting are associated with the previously known swirling spinning methods.

These problems are pointed out in the process described in German patent application DE 3348045.0 which seeks to spin fibers introduced into a wide funnel-shaped air chamber equipped with a set of nozzles supplying compressed air to create a swirling air flow increasing its peripheral velocity towards the narrow end of the funnel. is a discharge tube, which also serves as a spinning tube, connected to the suction source. The fibers transported by the passing air stream are captured by the tail forming yarn in the discharge tube, but the fibers are necessarily spirally incorporated into the structure around the forming yarn so that towards the discharge tube, the fibers are pulled from the discharge as the swirl speed increases. a funnel-shaped flap into the outlet tube which coaxially connects to the discharge tube. An auxiliary twisting unit is located in the outlet tube.

In such a system, no further twisting to the twisted twisting is feasible. which is applied at the free end of the tail. Nor is it possible to synchronize the tail rotation with the free end with the auxiliary twisting unit. Accordingly, the actual twisted twisting of the finished yarn will depend on the variable level of twisting applied to the tail of the yarn and thus, the yarn will be rigid. In addition, the extent of application of the twisted twisting operation cannot increase the rotational speed of the twisting unit; higher than the rotational speed applied to the tail, high yarn quality is not achieved at high production ratios.

increment of 1m which would thus be a tool

SUMMARY OF THE INVENTION

The present application represents a solution to the above problems and reduces conflicts with these problems in the application of the known open-end spinning methods including the known friction spinning methods.

It is an object of the present application to provide a method of loading a yarn assembly by an open-end friction spinning technique that overcomes or reduces the problems discussed above and allows high production ratios to achieve satisfactory degrees of twisting and high quality.

Accordingly, there is provided a method of loading a yarn assembly for an open-end spinning yarn by means of a twisting unit. supplying air entrained fibers to a defined assembly zone, maintaining a peripheral air flow around the air entrained fibers in the assembly zone, wherein said peripheral air flow is pressurized to radially compress the fiber assembly in the assembly zone and has the desired twist direction of the finished yarn as controlled by the twisting unit, and extracting air from said assembly zone in the axial direction of the fiber inlet and exhausting the fiber assembly formed in the assembly zone in the opposite axial direction to pass into the twisting unit.

The assembly zone is conventionally formed by the inner surface of the cylinder and the air flow enters the assembly zone in a direction that is generally said cylindrical surface. The air placed in the assembly zone by the axially and peripherally flowing air is circulated and is radially compressed so that the floating filaments and the tail forming yarn that extends into the assembly zone are generally free of contact with the peripheral stationary surface forming this assembly zone. Thus, laying the fibers and pulling the fiber assembly is possible in forming a yarn having a truly open end.

The circulating air pressure compresses the fiber-laying airflow, thereby allowing the fibers to be attached to the tail-forming tail and preventing the fibers from flowing to the waste while assisting the tail-shaped yarn spinning as an open end transporting the fibers to the assembly zone. proceeds to the distal end of the assembly zone into the suction source together with the compressed air. The outgoing air flow, which advances against the drawing direction of the fiber assembly, develops tangential to the fiber entering

'. The air that combs the fibers out of the fiber system is a useful pressure to keep the fibers in a stretched state, thereby assisting the tensile strength of the yarn.

The fibers are preformed in a commonly used fiber releasing device, such as a stream of air similar to the fibers.

The fiber assembly may be a friction spinning of this type.

and then transferred by pipeline to the assembly area axially pulled to a device as described in Australian Patent 501999 or US 4091602. Both patents are incorporated herein by reference.

Normally, the axis of the fiber assembly zone will be guided at right angles to the plane of rotation of the friction twisting elements, and thus, based on spatial assessment, the air delivery ducts may be guided at right angles to the passage defining the assembly zone or less inclined from the land end at an acute angle. In these assemblies, the filament air stream is subjected to a sharp sweep of direction after reaching the fiber assembly sonic entrance. This adversely affects the flow of air and fibers, as a result of this turbulence and the structure of the fiber system are affected. However, it is not possible to axially align the supply line with the passage of the more direct assembly zone where the current would not be so sharply changed from the original direction due to the design and purpose constraints required by the nature, operation and location of the rotating friction surfaces.

In addition, good operation of the open-end system requires that the rotation of the fiber assembly be undisturbed, the tail short and the fiber assembly zone near the fiber assembly inlet between the rotating friction surfaces. Otherwise, unwanted winding of the fiber assembly will occur and the regular rotation of the fiber assembly centered by this activity is prevented.

In accordance with another feature of the present invention, in the open-end spinning method of the fibers, the steps of entrainment of the fibers by an air stream conveying the entrained fibers to the fiber assembly zone are applied; attaching the fibers in said assembly zone to the rotating tail of the fiber assembly; and upstream of the assembly zone of the fiber assembly zone and extending the fiber assembly between two rotating frictional surfaces in rotation and contact conditions 2a to apply a twisted twist forming strand, wherein said fiber assembly zone is located in a conduit having axially connected with the passage of said friction surfaces and slanting inwardly relative to the plane of rotation, said fibers being fed to said fiber assembly line at the point of m between the assembly zone and the rotating surfaces and at an angle of not less than about 90 ° with respect to the axis of the fiber assembly pipe in terms of the inlet connection to the fiber assembly pipe.

The fibers are usually applied in a manner applied to the fiber assembly line along a path that is generally parallel to the usual plane of rotation of the respective components on which the friction surfaces are formed. Suitably, in both cases, the friction surfaces are stems to the axis of rotation and are arranged to form a gap therebetween through which the fiber assembly is drawn in contact with each friction surface after it leaves the assembly zone. on which the frictional surfaces are formed, rotate in opposite directions at the same peripheral speed, so that the contact area through which the fiber assembly passes maintains a fixed position axially to the axis of the fiber assembly pipe.

In the open-end spinning devices of the prior art, in which the fiber assembly is pulled through the gap between two rotating friction surfaces, there are two opposing frictional forces. One frictional force acts in the circumferential direction to coil or twist the yarn forming fibers, while the other frictional force acts in the axial direction due to the stretching of the fiber assembly through the frictional surfaces. The axial frictional force of the twisted fiber system, which can lead to yarn breakage, reducing reliability and manufacturing conditions.

These problems can be significantly reduced by introducing tapered friction surfaces to define the gap through which the fiber assembly is drawn and preparing the fiber assembly to enter the gap at the ends with a smaller gap, causing the diameter of the tapering surfaces to extend and exit at the ends with a larger diameter.

As a result of this treatment and the fact that the parts on which the friction surfaces are formed are driven at the same rotational speed in opposite directions, the surface speeds of the friction surfaces increase from slower to faster along the gap length from the inlet to the outlet end. Since the tapering surfaces cause friction on each side of the forming yarn, axial friction between the fiber assembly and the friction surfaces is advantageously utilized to increase and more easily pull the fiber assembly by the driving screw effect caused by the successive increase in surface speeds from smaller to larger end of tapering friction surfaces.

Overview of the drawings

One practical embodiment of the invention will now be described with reference to the accompanying drawings. In the drawings ^:

Giant. 1 is a schematic illustration of a method of spinning fibers into yarn;

Giant. 2 is an axial cross-section of a fiber assembly unit and a twisting friction device;

Giant. 3 is a cross-section taken along line 3-3 of FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, it can be seen that the fiber strand 6 is inserted into a suitable agitator 2, where the fibers are individually released from the strand and entrained by an air stream. Various types of commonly used fluff types can be used for this purpose. The fiber supply ratio is controllable in a known manner in relation to the specific fiber requirements, corresponding to the desired yarn production volume and the spun yarn withdrawn ratio.

The fibers of the agitator 2 are transported by the air flow through the duct 3 and are supplied to the fiber assembly unit 4. The fiber assembly unit is one of the main features of the present invention and will be described in more detail below. In the fiber assembly unit, air is vented via duct 5 to the suction source 7. The fiber assembly exiting the unit 4 is introduced into the friction twisting unit 8 and the finished twisted yarn is withdrawn from the twisting unit 8 by the pulling rollers 11 and discharged to the yarn winding spool.

Referring now to Fig. 2, we can see that the separate fibers entrained in the air stream are transported through the agitator line 3 as shown in Fig. 1 to a fiber assembly unit 4 which includes a tubular member 17 defining a central assembly zone 16. of fibers having the form of a cylinder open at both ends 20 and 21. The open end 20 is operatively connected to the suction device 7 as shown in FIG. 1, and the open end 21 is operatively cooperating with the fiber supply line 3 from the agitator to the assembly zone.

The shield 18 located in the region of the interconnection of the pipe 3 and the tubular member 17 is shaped to provide a smooth transition surface for changing the direction of flow of the fibers from the pipe 3 to the tubular member 17. The shield 18 also prevents this. so that the incoming fibers do not impact and start prematurely attaching to the fiber assembly that moves from the fiber assembly zone 16 to the twisting unit 8, as explained below.

The conduit 3 is tapered to accelerate the passage of air and fibers in order to stretch the fibers from an unorganized form that may exist or exist in the agitator. As a result, the fibers finally conveyed to the fiber assembly zone 16 are generally straight and directed generally parallel to the air flow direction. The fibers are also spatially distributed at the larger inlet end of the conduit 3, and as the fibers and the air flow accelerate towards the smaller supply end due to the reduction of the cross-sectional area of the conduit 3, the fibers become straight. At the same time, the fibers gradually divide sideways.

The resulting straightening, parallel displacement and laying of the fibers together with the protection of the fiber stream through the confined air layer causes the mass of fibers entering the fiber assembly zone 16 to form a circular shape similar to a hollow unrelated warp.

The through cavity 25 is located around the outside of the tubular member 17 at the fiber assembly zone 16 (not shown) and is connected through the passage 26 to the compressed air source. The cavity 25 is operatively connected to the fiber assembly zone 16 through the passages or grooves 28. 2) passing through the wall of the tubular member 17 in tangential relation to the inner wall of the tubular member 17. At least two such passages or grooves 28 are formed at opposite locations and in a common transverse plane relative to the axis of the fiber assembly zone 16.

In the fiber assembly zone 16, a rotating air flow is generated by functionally positioning the grooves 28, and this air flow assists the rotation of the fiber assembly in the fiber assembly zone 16 about its axis. The tangential direction of the passages or grooves 28 is selected such that the direction of rotation applied by the air to the fiber assembly is the same as the direction of twisting applied by the twisting unit 8. In addition to creating what has been stated in relation to the rotating air flow in the fiber assembly zone 16, entering through the passages or grooves 28 of sufficient pressure to induce a densified accumulation of fibers in a generally inwardly directed direction from the wall of the tubular member 17 and towards i

to the axis of the fiber assembly zone 16.

In addition, this compressed air operation contributing to the collection of the fiber assembly also creates a fiber free space between the fiber assembly and the inner surface of the tubular member 17 so that the fiber assembly can rotate freely as an open end. In this way, the conditions for creating a true free end for the tail of the formed yarn and for attaching the fibers thereto are achieved.

It is also useful that the suction device 7 extracts air from the fiber assembly zone 16 towards the open end 20 of the tubular member 17 and thus maintains axial tension of the fibers during assembly. This advantageously helps to keep the fibers in a stretched state during the fiber assembly process.

The densified fiber assembly is pulled from the end 21 of the tubular member 17 through an axially adjacent open end 29 of the shield 18 to enter the friction-spinning device 8 of the type described in my earlier U.S. Patent No. 4,091,605 and Australian Patent No. 5,01999 Both of these patents have already been mentioned in this specification. Shield

Referring to the twisting device of FIG. 2, we see that it is shown in detail on a stable support base 50 is important in guiding the fibers coming from the conduit 3 to change direction so as to enter the fiber assembly zone 16 axially without impacting the a densified set of fibers drawn to the inlet of the twisting device.

now to the preferred assembly 8, which comprises a forming portion of the base structure and supporting the rotatable outer friction ring 51 and the rotatable inner friction ring. The outer friction ring 5X rotates about axis 53 and the inner friction ring rotates about axis 54 that is not concentric with axis 53.

Outer ring 51 has a frusto-conical inner surface 55 concentric to axis 53 and inner ring 52 has frusto-conical outer surface 56 coaxial to axis 54. The angles of the respective stem stems are the same and the respective axes are positioned to form a narrow gap at one location. The system of fibers drawn from the fiber assembly zone 16 passes through this gap 58 where a twist is applied thereto as will be explained below.

The frustoconical inner surface 55 of the outer ring 51 is made of a friction material, such as rubber, and the outer surface 56 of the inner ring 52 is of the same or similar material. The inner and outer surfaces 55 and 56 are arranged to be frictional in Fig. 3. The inner torsion-driving contact as the ring is connected by a coaxial shaft 59 to a drive pulley 58 and this pulley can be coupled to a drive motor such as is shown). This drive arrangement ensures that both rings 51 and 52 rotate such that truncated cone-shaped surfaces move at the same peripheral speed in opposite directions.

An electric motor passes through the train between the inner and outer rings (not in the friction 58 in the frictional contact 3 with the respective friction surface, the fiber assembly being rolled on the axis so that actual twisting of the fiber assembly is achieved. at a speed, albeit in opposite directions, the fiber system will remain in a certain and stable position, even with the two surfaces mentioned.

It will be understood that other designs providing the same peripheral velocity of the respective outer and inner rings may be used to drive the inner and outer rings so that the gap 58 is maintained in a fixed position relative to the fiber assembly exiting the fiber assembly zone 6.

As can be seen in FIG. 2, the position of the gap 58 is axially aligned with the end 21 of the tubular member 17 and the guide tube 29 through which the fiber assembly is drawn from the fiber assembly zone 16. It can also be seen that the plane in which the rings 51 and 52 rotate is inclined relative to the axis of the tubular member 17, thereby allowing. For example, the pipe 3 supplying the fibers to the tubular member 17 can also be simply slanted. This provides a smoother transition of the path direction of the fibers entering the tubular member 17 to pass into the fiber assembly zone 16 and enter the gap 58 between the rotating friction surfaces 55, 56.

As already mentioned, by skewing the friction surfaces 55 and 56 relative to their respective rotational axes and entering the fiber assembly into the gap 58 at the smaller diameter end, the fiber assembly is subjected to an increase in peripheral velocity of the friction surfaces as it passes from the a larger gap diameter of 58.

This helps to facilitate the advancement of the fiber assembly forward through the gap 58, thereby reducing tension applied to the fiber assembly by the tension rollers 11 extending the yarn through the twisting device 8.

Claims (14)

1 1 PATE N T 0 V É Claims 1. Method compilation fibers for non-spindle spinning from torsion unit, characterized se t I m, comprising supplying the entrained fibers to a defined assembly zone, maintaining a peripheral air flow around the entrained fibers in the assembly zone, wherein said peripheral air flow is pressurized to radially compress the fiber assembly in the assembly zone and have the desired twist direction of the finished yarn as it is controlled by a twisting unit, exhausting air from said assembly zone in the axial direction of fiber entry, and drawing a fiber assembly formed in the assembly zone in the opposite axial direction to pass through the twisting unit. 2. The method of claim 1 wherein said fiber assembly zone is formed by the inner surface of the roll and the air flow enters said assembly zone in a direction that is generally tangential to said roll surface. 3. The method of claim 2, wherein said air stream enters said assembly zone through a plurality of holes in said roller surface spaced out circumferentially. 4. The method of claim 3, wherein the fibers are transported to said fiber assembly zone along a path that is substantially parallel to the plane of rotation of the respective components on which said friction surfaces are formed. 5. The method according to claim 3 or 4, wherein said friction surfaces are always inclined and inverted relative to the axis of rotation and are adjusted to provide a gap for pulling the fiber assembly in contact with each friction surface upon leaving the assembly zone. . An open-end yarn spinning method comprising the steps of delivering entrained fiber fixtures in a tail of an entrainment system of air stream fibers to a fiber assembly zone, said spinning fiber assembly zone, drawing the tail with fibers adhered thereto from the assembly zone in a direction opposite to the central stream air supplying the fibers to the fiber assembly zone and extending the fiber assembly between two rotating friction surfaces when rotating and in contact with each of them to form a twisting yarn, wherein said fiber assembly zone is delimited by a conduit having an axis following the passage between said friction surfaces and the inclined relative to the plane of rotation and said fibers are fed to said conduit at a location between the assembly zone and the rotating surfaces and at an obtuse angle relative to said conduit for melting the fibers downstream in a connection to said fiber assembly pipe. 5. The method of claim 5, wherein the fibers are first transported towards said fiber pipe for compilation fibers AFTER dragee, which is overall parallel in relationship ke together plane of rotation relevant part í, on which j sou formed by friction surfaces. 8. Method according to claim 6 or 7, characterized by. that the fibers are directed by a smooth transfer surface in order to help change the direction of the fiber flow to the axial direction of the assembly zone and prevent premature attachment of the incoming fibers to the drawn fiber assembly. 9. A method according to any one of Claims 5 to 8, wherein said friction surfaces are equally and oppositely angled relative to the axis of rotation and are adjusted to define a grip gap therebetween through which the fiber assembly is drawn in contact with each friction surface to form a twisted yarn. 10. The method of claim 9 including components rotating in opposite directions at the same peripheral velocity such that the compression region through which the fiber assembly passes maintains a fixed position axially adjacent the axis of the fiber assembly conduit. 11. The method of claim 9 or 10, wherein said friction surfaces taper to define said press area. 12. The method of claim 11 wherein said array of fibers enters said compression zone at the small diameter ends of said friction surfaces and exits said large diameter ends. An open-end spinning device for yarn of fibers comprising means for delivering fibers entrained by the air stream to the assembly zone to attach them to the rotating tail of the fiber assembly, means for drawing the tail with fibers adhered thereto from the assembly zone in the opposite direction air supplying the fibers to the fiber assembly zone and to pull the fiber assembly between two rotating frictional surfaces when rotating and in contact with them to twist the produced yarn by twisting, characterized in that said fiber assembly zone is delimited by a pipe having an axis adjacent the passage between said friction surfaces and being inclined to the plane of rotation thereof and that said fiber delivery means are configured to supply fibers to said conduit at a location between the assembly zone and the rotating surfaces and at an obtuse angle with respect to the axis of said fiber assembly line in the flow direction of the fiber assembly line. 14. The apparatus of claim 13, wherein the fiber delivery means transports said fibers into said fiber assembly line along a path that is generally parallel to a common plane of rotation of the respective components on which said friction surfaces are formed. Apparatus according to claim 13 or 14, characterized in that the application of a smooth transfer surface provides means to assist in changing the direction of the fiber stream into the axial direction of the assembly zone and preventing premature attachment of the incoming fibers to the drawn fiber assembly.