A method for operating a ring spinning machine and the spinning unit of a spinning machine.

Abstract

To provide a ring spinning machine capable of easily producing yarns with particularly high yarn uniformity and very few yarn defects, and a method of operating a spinning unit of the ring spinning machine.SOLUTION: There is provided a spinning unit that comprises: a draft machine 1; a ring spinning machine 10; and a yarn guide element having a rotationally symmetric through opening for a yarn, in which the yarn guide element is rotatably located in an area of a spindle between a draft machine and an end of the spindle turned toward the draft machine about a longitudinal axis of the through opening, the yarn is in contact with an inside of the through opening by the rotating spindle of the ring spinning machine located downstream of the yarn guide element in a yarn running direction, and only the yarn rotates the yarn guide element based on a rotatable arrangement of the yarn guide element.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a ring spinning machine having a plurality of spinning units arranged adjacent to one another, and a method for operating the spinning units of a ring spinning machine, wherein the spinning unit comprises: - a drafting device for drafting a sliver supplied to the drafting device; - a ring spinning device arranged downstream of the drafting device, the ring spinning device having a spindle for receiving a cop for winding up the drafted sliver forming a yarn, and - a yarn guide element having a rotationally symmetric through-opening for the yarn, the yarn guide element being rotatably arranged about the longitudinal axis of the through-opening in a region between the drafting device and the end of the spindle facing the drafting device. The present invention relates to a ring spinning machine and a method.

[0002] A ring spinning machine of the type described at the beginning is known, for example, from German Patent Application Publication No. 19909501. In a ring spinning machine, a sliver is converted into a yarn, which is wound up on a cop in the ring spinning machine. The ring spinning machine has a number of spinning units, in which a number of slivers are simultaneously converted into yarns, which are wound up on a number of cops. The main components of the spinning unit of a ring spinning machine are the drafting device and the spindle of the ring spinning device. In the drafting device, the sliver is drafted, for which purpose the drafting device has at least one inlet roller pair and one outlet roller pair. The contact line between the rollers of the roller pair forms a nip line through which the sliver is guided. One or more further roller pairs may be arranged between the inlet roller pair and the outlet roller pair. A drafting device having a total of three or four roller pairs is common. The drafting or stretching of the sliver is achieved by the speed difference between the roller pairs.

[0003] Downstream of the exit nipline of the exit roller pair, the sliver fibers are twisted and thus transformed into yarn. The twist is generated by a spindle, which rotates a cup (winding tube) onto which the yarn is wound. Various yarn guiding elements are known to guide the yarn from the exit nipline to the cup and to properly wind the yarn onto the cup, such as displaceable yarn guides, balloon limiting rings, and spinning rings. These elements are in contact with the yarn and, based on their friction, influence the growth of the twist in the yarn, which in turn affects the spinning result.

[0004] German Patent Application Publication No. 2343776 discloses a spinning unit for a ring spinning machine, equipped with a yarn guide positioned above the spindle, the yarn guide being rotatably supported by ball bearings. Both the yarn guide and the spindle have magnetic assemblies, which are configured such that the yarn guide is driven by the spindle, which rotates due to the magnetic field of the magnetic assemblies. The yarn guide rotates at a speed equivalent to that of the spindle. Additional twisting is intended to prevent yarn breakage. Configurations with magnetic assemblies are relatively expensive. Driving the yarn guide by the magnetic assemblies presupposes a constant distance between the spindle and the yarn guide. Therefore, the yarn guide still cannot perform normal vertical movement even when the yarn guide is displaced. The magnetic assembly on the spindle, in particular, further complicates doffing.

[0005] Similarly, German Patent Application Publication No. 3021632 discloses a yarn guide for a spinning unit of a ring spinning machine, which is rotatably supported and driven to rotate. Such a yarn guide is designed to improve the uniformity of the resulting yarn.

[0006] The uniformity of the yarn and the reduction of yarn defects in the produced yarn are limited by known ring spinning machines and known methods for operating the spinning unit of a ring spinning machine, or require expensive structures that impose other limitations. The fundamental problem of the present invention is to provide a ring spinning machine and a method for operating the spinning unit of a ring spinning machine that can easily produce yarn with particularly high yarn uniformity and very few yarn defects.

[0007] This problem is solved by the present invention with a ring spinning machine having the features of claim 1, and a method for operating the spinning unit of a ring spinning machine having the features of claim 7. Preferred developments of the ring spinning machine are described in dependent claims 2 to 6.

[0008] The ring spinning machine according to the present invention is distinguished by the fact that each spinning unit of the ring spinning machine has a yarn guide element with a rotationally symmetric through-opening for the yarn, the guide element being rotatable about the longitudinal axis of the through-opening and positioned in the region between the drafting device and the end of the spindle facing the drafting device. According to the present invention, the yarn guide element is in contact with the inside of the through-opening of the yarn guide element by a rotating spindle of the ring spinning machine, which is positioned downstream of the yarn guide element in the yarn travel direction, and only the yarn is formed and positioned to rotate the yarn guide element based on the rotatable arrangement of the yarn guide element.

[0009] According to the present invention, a sliver that is drafted and exits the drafting device is guided by a through-opening of a yarn guide element upstream of the inlet of the ring spinning machine. The yarn comes into contact with the inside of the through-opening by a rotating spindle of the ring spinning machine, which is located downstream of the yarn guide element in the yarn travel direction, and rotates the yarn guide element based on its rotatable configuration, with the axis of rotation extending parallel to the yarn path. The inside of the through-opening cooperates with the yarn guided through the through-opening to produce a yarn of particularly high quality, particularly high yarn uniformity, and with very few yarn defects. The high quality of the yarn is produced by the interaction between the rotating inside of the through-opening of the yarn guide element and the yarn guided through the through-opening.

[0010] The present invention is further based on the recognition that it is not necessary to actively drive a rotatably positioned thread guide element to obtain the desired thread uniformity. Rather, it is sufficient for the rotatable thread guide element to be driven by the thread itself. No additional drive mechanism is required.

[0011] The configuration of the thread guide element and the through-opening that engages with the thread is basically freely selectable. However, according to a particularly preferred configuration of the present invention, it is proposed that the through-opening is tapered at least partially in the direction toward the spindle. According to this configuration of the present invention, the through-opening has, for example, a hopper-shaped portion, in which the cross-section of the through-opening is tapered along the direction of thread travel. The thread guide element may be formed such that the through-opening is continuously tapered from the inlet opening of the thread guide element to the outlet opening of the thread guide element. Alternatively, however, the thread guide element may have a portion in which the cross-section of the through-opening remains equal in the direction of thread travel. The tapered portion ensures particularly reliable rotation of the thread guide element around the thread, thereby ensuring interaction between the inside of the through-opening and the thread, so that the thread has particularly high quality.

[0012] The internal configuration of the through-opening that engages with the thread is also basically freely selectable. However, according to a particularly preferred configuration of the present invention, it has been proposed that the internal surface of the through-opening has annular projections. According to this configuration of the present invention, the internal surface of the through-opening does not have a smooth surface, but rather has one or more annular projections that project toward the longitudinal axis of the through-opening and are arranged coaxially with the longitudinal axis. Based on these projections, the thread does not engage with the entire internal surface of the through-opening of the thread guide element, but merely contacts the projections in the region of the annular projections, and does not engage with the internal surface of the through-opening in the region of the recess extending between the projections. The partial interaction between the internal surface of the through-opening and the thread, caused by the projections, results in particularly high thread uniformity and a very small number of thread defects.

[0013] The configuration of the projections, as well as the number of projections, is basically freely selectable. However, according to a particularly preferred configuration of the present invention, it is proposed that the projections are formed by threads located on the inside of the through-opening. The use of threads to form the projections is outstanding because such projections can be manufactured particularly easily and inexpensively. The number of projections extending over the entire inner circumference along the length of the threads can be determined particularly easily. According to a particularly preferred configuration of the present invention, up to six, preferably two to five, and preferably three or four, annular projections are provided.

[0014] Essentially, the use of the yarn guide element according to the present invention in the region between the drafting device and the ring spinning device already produces particularly high yarn quality in the yarn formed from the sliver. According to an advanced form of the present invention, it has been proposed that a displaceable yarn guide is positioned in the region between the yarn guide element and the end of the spindle facing the drafting device. The use of a yarn guide that can move along the longitudinal axis of the spindle and is therefore called a displaceable yarn guide supplementarily enhances the spinning geometry, based on the fact that the twist of the spinning geometry grows based on friction.

[0015] The rotatable arrangement of the thread guide element is essentially freely selectable. For example, in its simplest configuration, the thread guide element can be used in a loose arrangement, in which case the thread is simply guided through a through-hole. To avoid unwanted movement of the thread guide element in the direction toward the spindle, a member with a thread hole may be provided, which is located in the area between the drafting device and the spindle and prevents the movement of the thread guide element in the direction toward the spindle. When a displaceable thread guide is preferably used, the thread guide element may be arranged such that it is in loose contact with the displaceable thread guide.

[0016] However, according to a particularly preferred configuration of the present invention, it has been proposed that the yarn guide element is rotatably positioned on a displaceable yarn guide. According to this configuration of the present invention, a support device is provided that rotatably supports the yarn guide element on the displaceable yarn guide. The configuration of the support device is basically freely selectable and particularly ensures the fixed positional arrangement of the yarn guide element in the spinning unit. The displaceable yarn guide can move along the longitudinal axis of the spindle. The movement is performed in relation to the cup structure and can affect the yarn balloon formed by the rotating yarn, thereby optimizing the yarn geometry. By incorporating a rotatable yarn guide element within or in contact with the displaceable yarn guide, or by forming a rotatable yarn guide element as the displaceable yarn guide, two functions, namely yarn uniformity and adjustment of the yarn balloon, can be combined into one.

[0017] In the case of a preferred configuration of a thread guide element having a tapering through-opening and a hopper shape resulting therefrom, for example, an arrangement may be proposed in which the thread guide element is loosely and rotatably supported within the thread hole of the thread guide, which is displaced in the region of its hopper-shaped portion. Alternatively, the thread guide element may be arranged not only in the thread guide but also in the thread guide which is displaced by rolling bearings.

[0018] According to the present invention, a method for operating the spinning unit of a ring spinning machine is proposed, in which sliver is supplied to a drafting device, drafted in the drafting device, and then the drafted sliver, after exiting the drafting device, is supplied to a ring spinning device located downstream of the drafting device, where the drafted sliver is converted into yarn and wound onto a cup located on the spindle. According to the present invention, the yarn is guided downstream of the drafting device through a rotationally symmetric through-opening of a yarn guide element, the yarn guide element being rotatable about the longitudinal axis of the through-opening in the region between the drafting device and the end of the spindle facing the drafting device.

[0019] A rotating spindle twists the drafted sliver, spinning it into yarn, which is then wound onto a cup positioned on the spindle. The rotating spindle causes the yarn to contact the inside of the through-opening of the yarn guide element, rotating the yarn guide element, with the axis of rotation oriented parallel to the direction of yarn travel. Based on the interaction between the inside of the yarn guide element and the yarn, particularly high yarn quality is produced, characterized by high yarn uniformity and minimal yarn defects.

[0020] Next, embodiments of the present invention will be described with reference to the drawings. [Brief explanation of the drawing]

[0021] [Figure 1] This is a schematic perspective view showing the arrangement of the drafting equipment and the ring spinning equipment located downstream. [Figure 2] This is a perspective view showing a displaceable yarn guide, which is located in the region between the drafting device and the spinning device and is equipped with the yarn guide element of the first embodiment. [Figure 3] Figure 2 is a perspective view showing the displaceable thread guide, along with the thread guide element of the second embodiment positioned within it. [Figure 4] Figure 2 is a perspective view showing the thread guide element. [Figure 5]Figure 3 is a perspective view showing the thread guide element.

[0022] Figure 1 schematically shows the draft device 1 of the spinning unit of a ring spinning machine, and the ring spinning machine 10 located downstream of the draft device 1. The ring spinning machine has a number of spinning units arranged side by side and driven by a central drive unit. The main components of the spinning unit are the draft device 1 and the spindle for housing the cups 12.

[0023] The drafting device 1, in the illustrated embodiment, has four roller pairs: an inlet roller pair (not shown), an intermediate roller pair 4, an outlet roller pair 3, and a converging roller pair 2. Roller pairs 2, 3, and 4 consist of top rollers 2a, 3a, and 4a and bottom rollers 2b, 3b, and 4b, respectively. Thus, the intermediate roller pair 4 consists of an intermediate top roller 4a and an intermediate bottom roller 4b. The intermediate top roller 4a and intermediate bottom roller 4b are each surrounded by a drafting apron. The outlet roller pair 3 has an outlet top roller 3a and an outlet bottom roller 3b, and the outlet top roller 3a and the outlet bottom roller 3b form a nip line at their contact line. The converging roller pair 2 of the converging device consists of a converging top roller 2a and a converging bottom roller 2b, which are surrounded by a converging apron. The conveying top roller 2a and the conveying bottom roller 2b similarly form a nip line, and in the illustrated embodiment, they also form a twist-stopping gap, and the twist generated by the spindle of the ring spinning machine 10 grows up to this twist-stopping gap. If a bundling device is not provided, the twist-stopping gap will be formed by the outlet roller pair.

[0024] The bottom rollers 2b, 3b, 4b are each driven via a single common shaft. The top rollers 2a, 3a, 4a are rotatably supported in the holding and pressing arms and are pressed against the bottom rollers 2b, 3b, 4b. At this time, the top rollers 2a, 3a, 4a are interlocked by frictional coupling. Coming from a flyer bobbin not shown here, the sliver first passes through the inlet nip line between the inlet top roller and the inlet bottom roller. Next, the sliver passes through the intermediate roller pair 4 and the outlet roller pair 3. When passing through the nip line between the conveying top roller 2a and the conveying bottom roller 2b, the sliver exits the drafting device 1. The sliver is drafted within the drafting device 1. The twist for making the sliver into yarn is applied downstream of the twist stop gap.

[0025] A cop 12 is arranged on the spindle. The yarn passes through the tail 8 forming the yarn hole of the displacing yarn guide 5 upstream of the cop 12. The yarn guide 5 is arranged in a lifting device extending in the machine length direction through the accommodation opening 6 of the fixed ring 17 arranged in the holding part 7, and the displacing yarn guide 5 is movable along the longitudinal axis of the spindle. Further, a balloon limiting ring 11 is provided, and this balloon limiting ring 11 is arranged on the holding body 15. The balloon limiting ring 11 limits the yarn balloon formed during the winding of the yarn. A ring rail not shown moves up and down along the spindle with the formation of the cop. One spinning ring 13 corresponding to the spinning unit is arranged on the ring rail. During the spinning operation, the ring traveler rotates in the spinning ring 13, and this ring traveler is driven by the rotating yarn balloon. Twist is applied to the yarn by the cop 12 rotating on the spindle. The twist grows until it reaches the twist stop gap of the drafting device 1 and stops there.

[0026] In the region between the ring spinning device 10 and the drafting device 1, yarn guide elements 9a, 9b having through openings for accommodating yarn are rotatably arranged. In the embodiments shown in FIGS. 2 and 3, the yarn guide elements 9a, 9b are loosely placed on the tail portion 8 of the displacing yarn guide 5. The yarn contacts the inner sides 18a, 18b of the through openings of the yarn guide elements 9a, 9b by means of a rotating spindle, causing the yarn guide elements 9a, 9b to rotate. At this time, the axis of rotation is parallel to the yarn path. In the embodiments shown in FIGS. 2 and 4, the yarn guide element 9a has a shape like a nut with a hexagonal cross-section on the outside. The yarn guide element 9a is loosely placed on the tail portion 8. The yarn guide element 9a has four protrusions 19 on the inner side 18a that protrude inward in the direction of the yarn, and these protrusions 19 are formed by internal threads 20.

[0027] In the embodiments shown in FIGS. 3 and 5, the yarn guide element 9b has a conical portion 21 connected to a cylindrical portion, whereby the through opening tapers in the direction of the yarn path. On the upper portion at the use position of the yarn guide element 9b, the inner side 18b of the yarn guide element 9b also has protrusions 19 formed by threads 20. The conical portion 21 is connected to the cylindrical portion.

Explanation of Reference Numerals

[0028] 1 Drafting device 2 Pair of conveying rollers 2a Conveying top roller 2b Conveying bottom roller 3 Pair of outlet rollers 3a Outlet top roller 3b Outlet bottom roller 4 Pair of intermediate rollers 4a Intermediate top roller 4b Intermediate bottom roller 5 Displacing yarn guide 6 Accommodating opening 7 Holding portion 8 Tail portion 9a, 9b Yarn guide elements 10 Ring spinning device 11 Balloon Restriction Ring 12 cups 13 Spinning Rings 15 Holding body 16 Aperture 17 Retaining ring 18a,18b inside 19 Protrusion 20 threads 21 Cone section

Claims

1. A ring spinning machine comprising a plurality of spinning units arranged adjacent to each other, wherein the spinning units are - A drafting device (1) for drafting slivers supplied to the drafting device (1), - A ring spinning device (10) located downstream of the drafting device (1), the ring spinning device (10) having a spindle that houses a cup (12) for winding up the sliver that has been drafted and formed into yarn, and - A thread guide element (9a, 9b) having a rotationally symmetric through-opening for the thread, wherein the thread guide element (9a, 9b) is rotatably arranged about the longitudinal axis of the through-opening in the region between the drafting device (1) and the end of the spindle facing the drafting device (1), In a ring spinning machine having, In the ring spinning apparatus (10), the yarn is in contact with the inside of the through-opening by the rotating spindle positioned downstream of the yarn guide elements (9a, 9b) in the yarn travel direction, and only the yarn rotates the yarn guide elements (9a, 9b) based on the rotatable arrangement of the yarn guide elements (9a, 9b). The inner surfaces (18a, 18b) of the through-opening have an annular projection (19) formed by screw threads (20). A ring spinning machine characterized by the following features.

2. The ring spinning machine according to claim 1, wherein the through-opening is tapered at least partially toward the spindle.

3. A ring spinning machine according to any one of claims 1 to 2, wherein a displaceable yarn guide (5) is arranged in the region between the yarn guide elements (9a, 9b) and the end of the spindle that is directed toward the drafting device (1).

4. The ring spinning machine according to claim 3, wherein the yarn guide elements (9a, 9b) are rotatably arranged on the displaceable yarn guide (5).

5. A method for operating the spinning unit of a ring spinning machine according to any one of claims 1 to 4, - The sliver is supplied to the drafting device (1), and the drafting device (1) is performed. - The drafted sliver is supplied to a ring spinning machine (10) located downstream of the drafting machine (1) after it has emerged from the drafting machine (1), and in the ring spinning machine (10), yarn is formed from the drafted sliver, and the yarn is wound onto a cup (12) located on the spindle, and - The thread is guided downstream of the drafting device (1) through a rotationally symmetric through-opening of thread guide elements (9a, 9b), and the thread guide elements (9a, 9b) are rotatably positioned about the longitudinal axis of the through-opening in the region between the drafting device (1) and the end of the spindle facing the drafting device (1). In the method, In the ring spinning apparatus (10), the yarn guide elements (9a, 9b) in the yarn running direction The rotating spindle positioned downstream causes the thread to contact the inside of the through-opening, and the thread alone rotates the thread guide elements (9a, 9b) based on the rotatable arrangement of the thread guide elements (9a, 9b), The inner surfaces (18a, 18b) of the through-opening have an annular projection (19) formed by a screw thread (20), and the thread contacts only the annular projection (19) in the region of the annular projection (19). A method characterized by the following:

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