FIELD OF THE INVENTION

The present invention relates to a ring spinning machine for spinning yarn and a method for spinning yarn. BACKGROUND OF THE INVENTION

On a ring spinning machine fibre roving, made e.g. from cotton, (man-made) flax or wool, is spun into a yarn. The ring spinning machine usually comprises multiple spinning positions. A spinning position is hereby understood as one position, where a fibre roving is spun into a yarn. Therefore, on each spinning position the fibre roving passes a drafting unit before it is twisted to form a yarn and collected on a spindle within a spinning unit. Within the drafting unit the fibre roving is drafted such that a desired degree of fineness is achieved. After leaving the drafting unit the fibre roving has the form of a relatively wide sliver. This sliver is then twisted together (with the aid of the spinning twist) to form the finished yarn. However, in this conventional ring spinning approach fibres arranged at the periphery of the fibre roving are locked in under high tension, meanwhile the center fibres are under low tension. In the finished yarn, the fibres located at the periphery thus break first. In order to avoid these disadvantages as far as possible, the drafting units of mod ern ring spinning machines further comprise compacting arrangements. In a com pacting zone of such a compacting arrangement the fibres are aligned more closely and parallel to each other thereby contributing to an evenly structured and dense fibre roving. After leaving such a compacting zone and passing the downstream spinning zone, an overall slimmer yarn with a smother surface is gained.

A mechanical compacting arrangement known from the prior art is disclosed in the W02006005207, which relates to a press roller unit for a compaction zone mounted downstream of a drafting zone of a ring spinning machine. The press roller unit comprises a geometrical-mechanical compactor having two compactor channels for the drafted sliver. The compactor is maintained between an exit roller and an additional compactor roller in a contactless manner and is positioned by a stationary stop so as to have little radial and axial play. A further compacting ar rangement known from the prior art is disclosed in the EP3134660, which relates to a traversable compactor arrangement. The traversable compactor arrangement allows a change of the position of the fibre roving in the drafting unit to a certain extent.

One disadvantage of the compacting arrangements known from the prior art is that the fibre roving only runs over a very small width of the rollers of the respective drafting unit. Consequently, the rollers, in particular elastic cots of the rollers, are worn down more frequently and the rollers can only be used for a limited time frame. It is an object of the invention to further improve ring spinning machines, in particular ring spinning machines with a compacting arrangement.

SUMMARY OF THE INVENTION

The disclosure relates to a ring spinning machine for spinning yarn and a method for spinning yarn. The ring spinning machine thereby aims to improve the overall lifetime of the rollers by controlling the local wear, in particular along a wider range of the width of the rollers of a drafting unit, as defined in more detail hereinafter. For an even utilization of the individual rollers of the drafting unit, a compacting element of the drafting unit comprises multiple, preferably at least three, laterally spaced apart compactor channels. Each compactor channel thereby provides an alternative lateral location for the path of the fibre roving through the drafting unit during operation. Each alternative path can thereby relate to a different operating state of the ring spinning machine. In order to position the fibre roving with respect to one of the multiple compactor channels, the drafting unit provides at least one guiding element, as explained in more detail below. Depending on the application, the guiding element can further be used to change the path of the fibre roving from one compactor channel to another and/or to change the path of the fibre roving through the drafting unit towards one of the compactor channels. In doing so, the rollers may be used for a significant longer time frame and the operational costs of the ring spinning machine are reduced. Generally, a ring spinning machine comprises per spinning position a drafting unit for drafting of a fibre roving before ring spinning the fibre roving to a yarn. The spinning of the fibre roving into a yarn is usually done in a (ring) spinning unit, arranged with respect to a path of the fibre roving downstream of the drafting unit. The drafting unit comprises with respect to the path of the fibre roving through the drafting unit a lower and an upper entry roller (also referred to in the following as entry rollers), a lower and an upper middle roller (also referred to in the following as middle rollers) and a lower and an upper exit roller (also referred to in the fol lowing as exit rollers). The entry rollers, the middle rollers and the exit rollers are each rotatable around a respective rotation axis extending in an axial direction of the ring spinning machine. Thus, the respective rotation axes of the rollers are ar ranged parallel to each other. Furthermore, the drafting unit comprises a com pactor roller. The compactor roller also rotates around a respective rotation axis extending in the axial direction. The before mentioned compacting element com- prising the at least three compactor channels is arranged during operation at least partially between the upper exit roller and the compactor roller. The at least three compactor channels are laterally spaced apart in the axial direction. During opera tion the fibre roving of a drafting unit travels first between the entry rollers, then between the middle rollers and finally between the exit rollers. Hence, with respect to the path of the fibre roving through the drafting unit, the middle rollers are ar ranged downstream of the entry rollers meanwhile the exit rollers are arranged downstream of the middle rollers. Meanwhile, the compactor roller is arranged downstream of the exit rollers, respectively the upper exit roller. To transport the fibre roving through the drafting unit, the lower rollers are usually the driving roll ers, wherein the upper rollers and the compactor roller are driven and arranged rotatable around a respective shaft of the rollers. Hence, the lower entry roller and the upper entry roller are arranged such that during operation the upper entry roller is pressed against and driven by the lower entry roller; the lower middle roller and the upper middle roller are arranged such that the upper middle roller is pressed against and driven by the lower middle roller and the lower exit roller and the upper exit roller are arranged such that the upper exit roller is pressed against and driven by the lower exit roller. The compactor roller is arranged such that during operation said compactor roller is also pressed against and driven by the lower exit roller. The upper rollers, in particular the upper entry roller and the upper exit roller, can fur ther comprise elastic cots. The elastic cots serve for a better grip and transport of the fibre roving through the drafting unit. Meanwhile the middle rollers can further each comprise aprons. According to invention a first guiding element is arranged upstream of the com pactor element to position the fibre roving with respect to one of the at least three compactor channels. Advantageously, the first guiding element is arranged up stream of the entry rollers, such that the fibre roving can be positioned through the whole drafting unit. Upstream of the entry rollers is thereby understood as from a view along the axial direction next to the entry rollers on a side facing away from the middle rollers. Depending on the application, a further second guiding element may be arranged between the entry rollers and the middle rollers. The first and/or second guiding element can each comprise one opening, e.g. in form of a slit or a through opening for inserting and guiding of the fibre roving. The openings of the first and/or second guiding element may also by funnel-shaped, in particular in di rection of the path of the fibre roving. With the help of the at least three compactor channels as well as the first and/or second guiding element alternative paths of the fibre roving through the drafting unit can be formed. This has the advantage, that the local wear of the rollers, in particular of the elastic cots and/or aprons, can be controlled. Hence, instead of having to change the rollers due to extensive local wear, the fibre roving can be assigned to another compactor channel. The first guiding element (and if present the second guiding element) further support the positioning of the fibre roving towards the assigned compactor channel.

In orderto changethe path of the fibre roving, the ring spinning machine preferably comprises a set of alternatively interconnectable second guiding elements, each second guiding element having the opening for guiding of the fibre roving at a dif- ferent position in axial direction (if interconnected). Advantageously, the number of (alternative) second guiding elements corresponds to the number of compactor channels. Also, each interconnected (alternative) second guiding element may be associated with at least one operating state of the ring spinning machine. Thus, for at least three compactor channels a set of at least three alternative second guiding elements is provided. When attached, each second guiding element of the set of alternative second guiding elements directs the fibre roving into a different com pactor channel in the operating state. The respective second guiding elements can hereby be attached through at least one interconnecting structure to a beam ex tending through the ring spinning machine or to the entry shaft of the upper entry roller or a middle shaft of the upper middle roller. The interconnection structure can thereby comprise a first interconnection element which is releasable interconnect- able to a second interconnection element arranged on the respective second guid ing element. In order to change the path of the fibre roving through the drafting unit, the second guiding element can then be detached from the interconnection structure and replaced with another second guiding element having the opening at a different position in the axial direction in an interconnected state on the intercon- nection structure. The respective alternative second guiding elements are thereby configured such that in an interconnected state of the respective second guiding element, the fibre roving is automatically assigned to a respective compactor chan nel, respectively the fibre roving is automatically guided towards said compactor channel. The set of second guiding elements can be used together with a first guid- ing element being fixed in one position or being displaceable as explained below. Also a variation is possible, wherein an equivalent set of first guiding elements may be provided.

Alternatively, the first and/or second guiding element can be arranged displaceable in the axial direction in order to change the path of the fibre roving. Both solutions have the advantage that the path of the fibre roving can be changed during the ring-spinning process. Preferably, the first and/or second guiding element can thereby be displaced between discrete positions in the axial direction. The amount of the discrete positions advantageously corresponds at least to the number of compactor channels. Thus, if at least three compactor channels are present, at least three discrete positions of the first guiding element or the first and second guiding element are available. Thereby, each discrete position is assigned to one compactor channel, respectively is configured to direct the fibre roving into the assigned com pactor channel. Preferably, each discrete position can be associated / corresponds to one operating state of the ring spinning machine. Furthermore, the discrete po sitions can be configured such that, the fibre roving automatically switches to the assigned compactor channel, when either the first guiding element or both guiding elements are in said discrete positions. Hereby, the first and second guiding ele ments can either be displaced independently from each other or simultaneously in order to change from one discrete position to another. The displacement can be easily realized, if the first and/or second guiding element are attached to a beam extending through the ring spinning machine in the axial direction. In order to dis- place the first and/or second guiding element the beam can be displaced. This setup is especially advantageous, if the respective beam is used for multiple guiding ele ments each assigned to a different drafting unit.

In one possible operating state of the ring spinning machine, the fibre roving ex tends essentially perpendicular to the axial direction and through one of the at least three compactor channels. In that case, the respective compactor channel and the opening of the first guiding element (and optionally also the opening of the second guiding element) overlap at least partially such that a thereto through going con nection axis is formed perpendicular to the axial direction. Further paths / operating states can be formed by establishing an offset between the first and second guiding element in the axial direction, wherein the second guiding element preferably re- mains essentially aligned in the axial direction with the assigned compactor chan nel. For example, a (first) offset can result in the fibre roving between the first and second guiding element, in particular between the entry rollers and the second guiding element, being slightly angled in respect to the fibre roving between the second guiding element and the respective compactor channel in use. Alternatively, an (second) offset may be used for a better positioning of the fibre roving at the center of one compacting channel: Therefore, the (second) offset between the opening of the first guiding element and the opening of the second guiding element can be chosen such that a first guiding edge of the opening of the first guiding ele ment and a second guiding edge of the opening of the second guiding element are aligned with respect to each other in the axial direction. The guiding edge can be defined as the edge of the respective opening configured to be in contact with the fibre roving in the respective operating state. Hereby, the first and the second guid ing edges are advantageously arranged opposite of each other. Preferably, the first and the second edge are further aligned to a center of one of the at least three compactor channels in the axial direction. Depending on the application, it can be sufficient, when only the second guiding edge of the opening of the second guiding element is aligned in the axial direction with the center of one of the at least three compactor channels. For e.g. a thick fibre roving it is also possible to arrange at least the second edge and the center of the respective compactor channel with an offset in the axial direction corresponding to half of the thickness of the fibre roving. The offset(s) by the first and/or second guiding element in the respective operating states can e.g. be established by the respective discrete position or an attached sec- ond guiding element out of a set of second guiding elements.

The compacting element is arranged during operation at least partially between the upper exit roller and the compactor roller, in particular at least partially between the upper exit roller, the lower exit roller and the compactor roller. Thereby, the compactor channels may be arranged on a tapered edge of the compacting ele- ment. Depending on the application, the compacting element can comprise at least four compactor channels. Each compactor channel is configured to compact a fibre roving passing through the compactor channel. Compacting of a fibre roving is thereby understood as reducing the overall cross section of the fibre roving by bringing the individual fibres of the fibre roving closer together. The tapered edge preferably protrudes in a wedge shaped gap between the upper and the lower exit roller. In a state where the upper exit roller is pressed against the lower exit roller, the wedge shaped gap is thereby formed downstream of the upper and lower exit roller. Downstream is thereby understood such that the wedge shaped gap is formed on the side of the upper and lower exit roller facing away from the middle rollers. Depending on the application, the compacting element can comprise a re cess for accommodating the compactor roller at least partly. Furthermore, the com- pacting element can comprise at least one clip for clamping the compacting ele ment around a compactor shaft of the compactor roller. The compactor shaft may be interconnectable to a holding structure, which in turn may be interconnectable to the exit shaft of the upper exit roller. In a mounted position of the compacting element on the compactor shaft the clip may circumvent the compactor shaft at least partly. Advantageously, the compacting element comprises two clips ar ranged in the axial direction opposite of each other with respect to the recess. The compacting element can comprise a curved surface, which follows (during opera tion) at least partially an outer contour of the upper exit roller. The curved surface may be spaced a distance apart from the surface of the upper exit roller. Further more, the compacting element may comprise at least one, preferably two, curved sled following during operation at least partially an outer contour of the lower exit roller. Depending on the application, the curved sled can comprise a gliding surface for gliding along the (rotating) lower exit roller during operation. Preferably, the compacting element comprises at least two curved sleds arranged in the axial di rection opposite from each other with respect to the recess. During operation, these at least two curved sleds may further be arranged adjacent to the compactor roller arranged in the recess. The lower surface of the compacting element may thus extend between the two opposite curved sleds. Preferably, the lower surface follows the contour from the respective curved sleds in the axial direction. The ta pered edge can thus be arranged between the lower surface which follows (during operation) at least partially an outer contour of the lower exit roller and the curved surface which follows (during operation) at least partially an outer contour of the upper exit roller. The compactor channels can thereby extend along the lower sur face of the compacting element. The lower surface can be defined as facing the lower exit roller. Each compactor channels may be funnel shaped.

In the context of this disclosure, it is understood, that the lower rollers can extend through the ring spinning machine and may be used simultaneously at multiple spinning positions, respectively for multiple drafting units. Furthermore, two spin ning positions may be assigned to one weighting unit. Consequently, one weighting unit can be assigned to two drafting units. A ring spinning machine may comprise several weighting units with at least two drafting units per weighting unit. The described embodiments of the ring spinning machine can serve for the execu tion of a method for ring spinning according to the invention. The previously de scribed embodimentsof the ring spinning machine hereby disclose at the same time a corresponding method for ring spinning yarn and vice versa. This method can include changing the fibre roving from one compactor channel to another by dis- placing only the first guiding element (without a second guiding element being pre sent) in the axial direction between discrete positions or by displacing the second guiding element in the axial direction between discrete positions (with the first guiding element staying in a stationary position, respectively in the same position) or by displacing the first guiding element and second guiding element in the axial direction between discrete positions. Alternatively, the method can include chang ing the fibre roving from one compactor channel to another by providing the set of second guiding elements each having the opening to guide the fibre roving at a different position in the axial direction when interconnected and exchanging the respective second guiding elements. Thus, the fibre roving can be changed from one compactor channel to another during ring spinning, without stopping the ring spinning process. It is to be understood that both the foregoing general description and the following detailed description present embodiments, and are intended to provide an over view or framework for understanding the nature and character of the disclosure. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illus- trate various embodiments, and together with the description serve to explain the principles and operation of the concepts disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

The herein described invention will be more fully understood from the detailed de scription given herein below and the accompanying drawings which should not be considered limiting to the invention described in the appended claims. The draw ings are showing:

Fig. 1 A perspective view of a first version of two drafting units of a ring spin ning machine according to the invention;

Fig. 2 A side view of the drafting units according to Fig. 1 ; Fig. 3 A perspective view of part of the drafting units of Fig 1 without the weighting arm;

Fig. 4 An embodiment of a second guiding element according to Fig. 1 ; Fig. 5 A compactor unit according to Fig. 1 in a perspective view; 5 Fig. 6 The compactor unit according to Fig. 5 in a side view; Fig. 7 An embodiment of a compacting element according to Fig.5; Fig. 8 A schematic view of various operating states a), b), c), d) of a drafting unit with four alternative compacting channels and a first and a second guiding element; 0 Fig. 9 A schematic view of various operating states a), b), c) of a drafting unit with three alternative compactor channels and a displaceable second guiding element;

Fig. 10 A schematic view of various operating states a), b), c) of a drafting unit with three alternative compactor channels with an exchangeable sec 5 ond guiding element;

Fig. 1 1 A schematic view of further operating states a), b), c) of a drafting unit with three compactor channels and a first and a second guiding ele ment.

DESCRIPTION OF THE EMBODIMENTS 0 Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all features are shown. Indeed, embodiments disclosed herein may be embodied in many dif ferent forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Figure 1 to Figure 7 show a first variation of a ring spinning machine shown only in parts. The first variation is thereby comprising (at least) two spinning positions, wherein each spinning position can be assigned a drafting unit 1 according to the disclosure. Each drafting unit 1 comprises with respect to a path of the fibre roving 2 through the drafting unit 1 a lower and an upper entry roller 3, 4, a lower and an upper middle roller 5,6, a lower and an upper exit roller 7, 8 and a compactor roller

9. The rollers 3, 4, 5, 6, 7, 8, 9 usually rotate around a respective rotation axis extending in an axial direction (x-direction). As described in the general description the lower rollers 3, 5, 7 drive the upper rollers 4, 6, 8 and the compactor roller 9, when said rollers 4, 6, 8, 9 are pressed against one of the lower rollers 3, 5, 7 during operation.

The first variation of the ring spinning machine comprises per drafting unit 1 a com pacting element 1 1 and a first and a second guiding element 1 2, 13. As shown best in Fig. 2, the compacting element 1 1 is arranged between the upper exit roller 8 and the compactor roller 9. Meanwhile, the first guiding element 12 is arranged upstream of the entry rollers 3,4 and the second guiding element 13 is arranged between the entry rollers 3, 4 and the middle rollers 5, 6. A tapered edge 1 5 (see Fig. 7) of the compacting element 1 1 is protruding in the (downstream) wedge shaped gap 10 between the upper and the lower exit roller 8, 7. The laterally spaced apart compactor channels 14 are forming alternative lateral locations for the path of the fibre roving 2. The compacting element 1 1 may thereby be posi tioned through a holding structure 20, which holds the compactor shaft 19 of the compactor roller 9. The holding structure 20 is preferably interconnected to the exit shaft 18 of the upper exit roller 8, as shown in Fig.1 . The holding structure 20 may further comprise a spring 28, preferably a flat spring pressed against the weighting arm 33 of the weighting unit 30.

In Fig. 3 and Fig. 4, the first and second guiding elements 1 2, 13 can be seen. The first guiding element 1 2 can be arranged on a beam 31 (see Fig. 8a), 9a), 10a)) extending in the axial direction through the ring spinning machine. The second guiding element 13 can be interconnected to the middle shaft 17 through an inter connection structure 26. The first and second guiding element 12, 13 may each comprise one opening 25 for the fibre roving 2. The respective opening 25 may be in form of a slit arranged in the upper direction, as e.g. illustrated for the second guiding element 13. Alternatively, the opening 25 may be a through hole, as e.g. illustrated for the first guiding element 1 2 in Fig. 3. As can be seen in Fig.4 the interconnection structure 26 can further be releasable interconnected to two sec ond guiding elements 13 for the two spinning positions, each assigned to one drafting unit 1 of the same weighting unit 30. By exchanging one second guiding element 13 with another guiding element featuring an opening at another axial position (x-direction) the local position of the fibre roving can thus be altered. Fig. 2 further illustrates an apron structure 29 interconnected to the middle shaft 17. The apron structure 29 comprises at least one rim for an apron 27 of the upper middle roller 6. The apron 27 of the upper middle roller 6 extends around the re spective rotation axis of the upper middle roller 6 in a circumferential direction. Also the lower middle roller 5 comprises an apron 27 in the shown embodiment.

In Fig. 5 and Fig. 6 a subassembly, namely the compactor unit 32 of the ring spin ning machine can be seen (together with the lower exit shaft 8). The compactor unit 32 comprises the holding structure 20 holding the compactor shaft 19 with respect to the exit shaft 18. The compactor unit 32 further comprises at least one upper exit roller 8, at least one compactor roller 9 as well as at least one compacting element 1 1 . The compactor shaft 19 and the exit shaft 18 extend in an axial direc tion. Preferably, the compactor unit 32 comprises two compactor rollers 9 ar ranged rotatable around the compactor shaft 19 and two upper exit rollers 8 ar ranged rotatable around the exit shaft 18. The holding structure 20 can be ar- ranged in axial direction between the compactor rollers 9, respectively, between the upper exit rollers 8, 8.

The dismounted compacting element 1 1 of a drafting unit 1 is further shown sep arate in Fig. 7. It can be seen that the compacting element 1 1 comprises a tapered edge 1 5 and three laterally spaced apart compactor channels 14. The compacting element 1 1 can further comprise at least one recess 21 to accommodate the com pactor roller 9 in said recess 21 . Furthermore, the compacting element 1 1 may comprise two clips 22 for interconnecting the compacting element 1 1 to a com pactor shaft 19 of the compactor roller 9. Preferably, the two clips 22 are thereby arranged in the axial direction opposite each other with respect to the recess 21 . Advantageously, the compacting element 1 1 comprises a curved surface 23, which follows during operation at least partially an outer contour of the upper exit roller 8, as can be seen in Fig. 6. The curved surface 23 is spaced a distance apart from the surface of the upper exit roller 8 forming a gap. Furthermore, the compacting element 1 1 may comprise at least two curved sleds 24 following during operation at least partially an outer contour of the lower exit roller 7. Depending on the ap- plication, the respective curved sled 24 can comprise a gliding surface for gliding along the (rotating) lower exit roller 7 during operation. Preferably, the compact ing element 1 1 comprises two curved sleds 24 arranged in the axial direction op posite with respect to the recess 21 and the next to the compactor roller 9.

Figure 8 schematically shows a drafting unit 1 illustrating the upper entry roller 4, the upper middle roller 6 comprising an apron 27, the upper exit roller 8 and the compactor roller 9. The lower rollers 3, 5, 7 are not shown for illustration purposes. The shown drafting unit 1 further comprises a first and a second guiding element 12, 13 and a compacting element 1 1 with four compactor channels 14. However, also other amounts of compactor channels are possible. The first guiding element 12 is arranged upstream of the entry roller(s) 4 and the second guiding element

13 is arranged between the entry and the middle rollers(s) 4, 6. In Figure 8 a) - 8d) four different operating states of the drafting unit 1 can be seen. In all four operating states, an opening 25 of the first guiding element 1 2 and an opening 25 of the second guiding element 13 and either one of the four compactor channels 14' overlap at least partially such that a through going connection axis is formed perpendicular to the axial direction. In each operating state the fibre roving 2 is as- signed to another compactor channel 14'. To change from one operating state to another, the first and second guiding elements 1 2, 13 can both be displaced in the axial direction. Each shown operating state may relate to a discrete position of the displaceable first and second guiding element 1 2, 13, as explained above. For an evenly distributed wear of the rollers, cots or aprons the shown operating states are preferably used one after the other. E.g. if the path of the fibre roving according to

Figure 8a) is worn down, the path may be changed to the path according to Figure 8b) and so on. For the shown operating states, the second guiding element 13 is optional. If only a first guiding element 1 2 is present, the fibre roving 2 can be changed from one compactor channel 14 to another by displacing the first guiding element 1 2 in the axial direction between discrete positions.

Figure 9 schematically shows further operating states of a drafting unit 1 similar to Figure 8. The drafting unit 1 of Figure 9 differs from the drafting unit of Figure 8, in that three compactor channels 14 are present. The drafting unit 1 also comprises a first guiding element 1 2 upstream of the entry roller(s) 2 and a second guiding element 13 between the entry rollers(s) 3 and the middle roller(s) 6. From the three operating states shown (Figure 9a) - 9c)) only Figure 9b) illustrates a case, where an opening 25 of the first guiding element 12 and an opening 25 of the second guiding element 13 and one of the three compactor channels overlap such that a through going connection axis is formed perpendicular to the axial direction. In each operating state the fibre roving is assigned to another of the compactor channels. To change from on operating state to another, the opening 25 of the second guiding element 13 can be displaced in the axial direction. This can be achieved by displacing only the second guiding element 13 (as indicated by the arrows) with the first guiding element 12 staying in the same position. Alterna tively, this can also be achieved by exchanging the second guiding element 13 with another second guiding element having an opening at another axial position, as illustrated in Figure 10. In each operating state illustrated in Figure 10a) - 10c) a different second guiding element 13a, 13b, 13c of a set of (alternative) guiding elements is used, wherein each second guiding element 13a, 13b, 13c has the opening 25 at a different position in the axial direction, when attached. In the in terconnected state, the respective second guiding element 13a, 13b, 13c auto- matically guides the fibre roving 2 in the assigned compactor channel. Meanwhile, in all shown operating states of Figure 9 or Figure 10, the position of the first guid ing element 32 is fixed. Thus, between the first and the second guiding element

12, 13, in particular between the entry rollers 4 and the second guiding element

13, the fibre roving 2 may be angled with respect to the fibre roving 2 between the second guiding element 13 and the compactor channel 14', if an offset is present between the opening 25 of the first guiding element 1 2 and the opening 25 of the second guiding element 13, as e.g. illustrated in Figure 9a) and Figure 9c). Figure 11 a) - 11 c) illustrate three further possible operating states of the ring spin ning machine, wherein the opening 25 of the first guiding element 1 2 and the opening 25 of the second guiding element 13 are (slightly) offset with respect to each other in the axial direction. In the operating states according to Figure 11a) and Figure 11c) a first guiding edge 34 of the opening 25 of the first guiding ele ment 1 2 and a second guiding edge 35 of the opening 25 of the second guiding element 13 are aligned with respect to the axial direction (x-direction). Further more, the first and second guiding edge 34, 35 are aligned with a center of the respective compactor channel 14' used in that operating state. As can be seen, the first and the second guiding edges 34, 35 are arranged opposite of each other with respect to the axial direction. This setup has the advantage that the position of the fibre roving 2 is more accurate in the axial position and can be adjusted such that the fibre roving 2 is fed in the center of the respective compactor channel 14'. Figure 11c) differs from Figure 11a) in that in Figure 11c) the first and second guiding elements 1 2,13 are interconnected and can thus be displaced together in order to change the compactor channel 14 for the fibre roving 2. In the operating state according to Fig. 11b) the fibre roving 2 is only positioned through the second guiding edges 35, which is positioned essentially at the same position in the axial direction as the center of the compactor channel 14' in use. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without depart ing from the scope of the invention. LIST OF DESIGNATIONS

1 Drafting unit 20 Holding structure

2 Fibre roving 21 Recess

3 Lower entry roller 22 Clip

4 Upper entry roller 23 Curved surface

5 Lower middle roller 24 Curved sled

6 Upper middle roller 25 Opening

7 Lower exit roller 26 Interconnection structure

8 Upper exit roller 27 Apron

9 Compactor roller 28 Spring

10 Wedge shaped gap 29 Apron structure

1 1 Compacting element 30 Weighting unit

12 First guiding element 31 Beam

13 Second guiding element 32 Compactor unit

14 Compactor channels 33 Weighting arm

1 5 Tapered edge 34 First edge

16 Entry shaft 35 Second edge

17 Middle shaft

18 Exit Shaft

19 Compactor shaft