EP3670718B1 - Ring spinning machine with drafting units - Google Patents

Description

The invention relates to a ring spinning machine with drafting systems which are formed by pairs of rollers which rotate at different rotational speeds and have machine-long lower roller strands which are formed by partly corrugated roller sections and are equipped with a length compensation device.

Ring spinning machines in which machine-long drafting arrangements are positioned both in the area of the machine front side and in the area of the machine rear side have been known for a long time and are in part described in great detail in numerous patent applications.

Such machine-long drafting arrangements have lower rollers, which are generally formed by machine-long lower roller strands, which in turn consist of a large number of roller segments connected to one another in a torque-proof manner.

In the area of the work stations, upper rollers rest on the lower roller strands, which are taken along by the lower roller strands in a frictionally engaged manner and form pairs of rollers in connection with the lower roller strands. The machine-long bottom roller strands are usually driven by a relatively powerful electric motor arranged at the end of the machine in a drive frame of the textile machine. B. ensures via an interposed reduction gear that the input, the middle and the output pairs of rollers rotate at different speeds and thereby distort the presented fiber material properly.

With high-performance drafting systems, such as those used on modern ring spinning machines and, for example, in the U.S. 7,937,924 B2 are described, the middle roller pairs of the drafting system are also often equipped with so-called drafting aprons. The lower roller strands of such drafting systems are usually also rotatably mounted in the area of so-called punches, with the input lower roller often being mounted on a carriage that is arranged on the punch so that it can be displaced in a defined manner so that the drafting width of the predrafting field is adjustable. The bottom roller strands of the pair of middle rollers and the pair of output rollers are also often stored in corresponding storage devices on punches.

In ring spinning machines designed in this way, which usually have a large number of work stations arranged next to one another and each served by one of the drafting units, various problems often occur in the area of the drafting units if no appropriate countermeasures are taken. The stretching rollers of the bottom roller strands are not only subjected to relatively high torsional stresses, for example, due to the torque introduced, but also often result in linear expansion of the stretching rollers due to heating. In particular, the degree of torsion of the individual lower roller strands depends on various factors, such. B. from the diameter of the stretching rollers, from the bearing friction, from the inhibition by the drawn delay straps, etc. and can be quite different.

Different torsions in the drafting rollers of the bottom roller strands do not necessarily have a negative effect while the drafting system is running, but, since the torsions in the drafting rollers build up and decrease at different times, often lead to draft errors when the drafting system is accelerated or decelerated. This means that depending on whether the torsion of a drafting roller is leading or trailing behind the drafting roller upstream or downstream of it, there are thin or thick points in the yarn, which represents a loss of quality or can lead to yarn breaks.

Various proposals have already been made in the past in order to prevent as far as possible different torsions in drafting systems, especially when the lower roller strands are relatively long, or at least to reduce them to a harmless amount.

It has been proposed, for example, to arrange a further gear train at the end of the lower roller strands opposite the drafting system drive, which ensures that the different angular positions of the lower roller strands that occur when the drafting system starts up, runs out or is at a standstill are at least kept the same.

Furthermore, in connection with ring spinning machines whose drafting systems are very long, it has also been proposed in the past to equip the bottom roller strands with drafting system gears, which are each arranged approximately in the longitudinal center of the bottom roller strands and each of the long bottom roller strands with at least one of its free ends to equip a torque initiating auxiliary motor.

However, arranging a drafting system transmission in the area of the longitudinal center of the drafting rollers has the considerable disadvantage that the sequence of division of the work stations is interrupted at this point and the structure of the ring spinning machine is thus significantly complicated.

Another, comparable, e.g. in the DE 10 2015 010 854 A1 The proposal described provides for the use of strong drive devices at both ends of the lower roller strands and in this way to avoid torsions in the lower roller strands as far as possible.

In addition, e.g. B. by the DE 10 2005 054 817 A1 , A ring spinning machine is known whose drafting system has a main drive on the machine input side and further auxiliary drives in the course of the lower roller strands. This well-known, relatively expensive drafting system arrangement could not prevail in practice.

The US 949 504 A , the FR 752 786 A and GB 1 023 322 each disclose a connecting piece for rigidly connecting two roller segments. Due to the rigid connection, however, no linear expansion of the roller segments can be compensated.

Since uncontrolled linear expansion of the drafting system rollers can also lead to serious malfunctions in the ring spinning machine, various proposed solutions have already been proposed with regard to this problem.

In practice, in connection with ring spinning machines that have machine-long drafting units, it is widespread, for example, for the bottom roller strands of these drafting units to consist of two roller segments of approximately the same length, which in turn are composed of a large number of roller sections. The two roller segments, which are approximately the same length, are each connected to a drive at the end and are axially displaceable in the area of the center of the ring spinning machine via a so-called cylinder separation, but are not connected in a rotationally fixed manner. This means that by means of such a known cylinder separation, length expansions of the roll segments caused by heat can be compensated for; However, a torque transmission from one roller segment to the other roller segment is not possible by means of such a cylinder separation.

In a further known embodiment it is provided that with machine-long Drafting systems each at the beginning of the lower roller strands a cardan shaft is installed, which compensates for the longitudinal expansion of the relevant lower roller strand occurring during operation of the ring spinning machines. However, such a construction is not only quite complex, but with such a design, the entire linear expansion of a lower roller strand acts in only one direction, which is not entirely unproblematic.

Proceeding from the prior art described above, the object of the invention is to create a ring spinning machine whose drafting systems are designed in such a way that the lower roller strands are not overstressed and damaged in the process, neither by torsion nor by elongation.

According to the invention, this object is achieved in that the length compensation devices connected to the lower roller strands are each designed and arranged in such a way that both length compensation and transmission of torque is possible with respect to the lower roller strands, with the length compensation devices comprising a compensation shaft and a receptacle, which form interlocking shaft-hub connections and the roller segments of the lower roller strands are each connected to the balancer shaft in an axially displaceable manner via the receptacle.

Advantageous embodiments of the invention are the subject matter of the dependent claims.

This means that the design and arrangement of the length compensation devices according to the invention not only reliably ensures that the torques introduced into the lower roller strands by a drive during operation of the ring spinning machine are always transmitted over the entire length of the lower roller strands, but also ensures that, if necessary, the length compensation devices also immediately compensates for length expansions that occur in the area of the lower roll strands and are usually caused by heat.

According to the invention, it is provided that the length compensation devices each comprise a compensation shaft and a receptacle, which form a positive shaft-hub connection, which preferably has a so-called P4C polygon profile. Such P4C polygon profiles have, in contrast to the no notch effect compared to most conventional, axially displaceable profiles. This means that since a shaft with a P4C polygonal profile is only subjected to torsion, such polygonal shafts have e.g. For example, splined profiles have a fatigue strength that is almost 30% higher.

Advantageously, the balancing shaft is rotatably mounted in a lower roller bearing via a bearing sleeve. According to the invention, the roller segments of the lower roller strands are each connected to the balancer shaft in an axially displaceable manner via the receptacle. The Roller segments of the lower roller strands preferably each have a connecting piece with the receptacle.

Such an embodiment has the particular advantage that the affected roller segments of the lower roller strands are not only reliably connected in terms of drive via the compensating shaft of the length adjustment device according to the invention, but are also positioned securely and correctly via the bearing sleeve rotatably supported in a lower roller bearing.

Furthermore, the inventive design of the balancer shaft in conjunction with the associated receptacles of the roller segments of the lower roller strands also ensures that if z. B. heat-related changes in length of the roller segments of the lower roller strands should come, these are always immediately compensated by axial displacements between the balancer shaft and the recordings.

In an advantageous embodiment, the connecting pieces with the receptacles are each fastened in one of the roller segments of the lower roller strands in a rotationally fixed manner by means of a press fit. With such a design, a reliable and durable connecting device can be implemented in a relatively simple manner in the end region of the roller segments of the lower roller strands, which is also relatively inexpensive to produce.

A very advantageous embodiment is also given when the lower roller bearing for the length compensation device is supported on a punch which is arranged approximately in the area of the machine center of the ring spinning machine. Such a support ensures in a relatively simple manner that the roller segments of the lower roller strands are properly rotatably mounted over their entire length, in particular also in the area of the length compensation device.

The lower roller bearing is preferably designed in such a way that the bearing sleeve equipped with a balancing shaft can be inserted from above into the hinged lower roller bearing and locked there. Since the bearing sleeve can be positioned and fixed in the lower roller bearing at any time relatively easily and without great expenditure of time, such a design makes it possible to replace, for example, worn or damaged ones Lower roll strands considerably easier and simplified.

In an alternative embodiment, the length compensation device could in principle also be formed by a shaft-hub connection, the compensation shaft of which is designed as a splined shaft that corresponds to corresponding inner centering in the receptacles. However, compared to a length compensation device whose balancer shaft has a P4C polygon profile, a length compensation device that has a multi-spline shaft has the not inconsiderable disadvantage that notch effects occur with multi-spline shafts, which in the long term have a negative effect on the fatigue strength of the length compensation device can. A P4C polygon profile enables higher torque transmission compared to other form-fitting shaft-hub connections or can be made correspondingly smaller for the same torque. A P4C polygonal profile enables the shaft and hub to be displaced particularly well in relation to each other under torque and centric load application. The distances between the length compensation devices or the lengths of the roller segments can thus be more than 60 meters.

The invention is explained in more detail below with reference to an exemplary embodiment illustrated in the drawings.

Fig. 1

eine Ringspinnmaschine, deren Streckwerke Walzenpaare aufweisen, wobei die Unterwalzenstränge jeweils mit einer erfindungsgemäß ausgebildeten Längenausgleichseinrichtung ausgestattet sind,

Fig. 2

in Seitenansicht und in einem größeren Maßstab ein Streckwerk einer Ringspinnmaschine, wobei das Streckwerk, wie üblich, ein Eingangs-, ein Mittel- und ein Ausgangswalzenpaar aufweist,

Fig. 3

in Draufsicht stark schematisch die Unterwalzenstränge einer Ringspinnmaschinen-Streckwerksanordnung,

Fig. 4

in leicht perspektivischer Ansicht zwei Walzensegmente eines Unterwalzenstranges sowie eine zwischen den Walzensegmenten angeordnete, erfindungsgemäß ausgebildete Längenausgleichseinrichtung,

Fig. 5

in perspektivischer Ansicht die Einzelteile einer Längenausgleichseinrichtung gemäß Fig. 4,

Fig. 6

in Seitenansicht, teilweise im Schnitt, die Längenausgleichseinrichtung gemäß Fig. 4 im Montagezustand

It shows:

1

a ring spinning machine, the drafting systems of which have pairs of rollers, with the lower roller strands each being equipped with a length compensation device designed according to the invention,

2

a side view and on a larger scale of a drafting system of a ring spinning machine, the drafting system having, as usual, an input, a middle and an output pair of rollers,

3

highly schematic plan view of the bottom roller strands of a ring spinning machine drafting system arrangement,

4

in a slightly perspective view of two roller segments of a lower roller strand as well as a length compensation device arranged between the roller segments and designed according to the invention,

figure 5

a perspective view of the individual parts of a length compensation device 4 ,

6

in side view, partially in section, according to the length compensation device 4 in assembly condition

The 1 shows a schematic, cross-sectional view of a ring spinning machine 1 whose drafting units 10 each have pairs of rollers 21, 22, 23, with the lower roller strands 21u, 22u, 23u each being equipped with a length compensation device 31 designed according to the invention.

In the illustrated embodiment, the ring spinning machine 1 has a pedestal 2, from which vertical standpipes 3 extend upwards, which carry suction channels 4, which are preferably rectangular in cross section. Bridge pieces 5 are fastened to the standpipes 3, which in turn hold two parallel support tubes 6 running in the longitudinal direction of the machine, on which the bearing housings for a large number of ring spinning spindles 7 are fixed, on which spinning cops 8 are wound during the spinning operation.

In the exemplary embodiment shown, the so-called punches 9 are fastened to two support tubes 11 extending in the longitudinal direction of the machine. The lower strands of rollers 21u, 22u, 23u of the drafting units 10 are mounted on the punches 9, each of which has pairs of rollers 21, 22 and 23, which rotate at different speeds and thereby warp a template material 12.

The ring spinning machine 1 also has vertically arranged support columns 13 for a feed material gate 14. In the exemplary embodiment, feed bobbins 15 hang in the feed material gate 14, the feed material 12 of which is deflected via a deflection rod 24 or the like and drawn off by the drafting units 10.

A part of the movement mechanism 25 of the ring spinning machine 1 is also installed laterally next to the suction channels 4 . That is, in this area are the lifting devices for the ring rail 18, the balloon constriction rings 19 and the vertically displaceable mounted Thread guide 20 arranged.

Furthermore, a bobbin changing device 33 is installed on a boom 32 of the base frame 2 of the ring spinning machine 1, which consists essentially of several scissor systems with scissor arms, a gripper bar and tube grippers arranged on the gripper bar. The scissor systems can be actuated by means of a push/pull tube that runs along the ring spinning machine 1 .

2 shows a side view and on a larger scale of a drafting system 10 whose machine-long, drivable lower roller strands 21u, 22u and 23u are each equipped with a length compensation device 31 designed according to the invention. As is known, such drafting systems 10 have not only lower roller strands 21u, 22u and 23u but also upper rollers 21o, 22o and 23o, which rest on the lower roller strands 21u, 22u and 23u during spinning and are carried along by them in a friction-locked manner.

The lower roller trains 21u, 22u and 23u are mounted on punches 9, for example, via carriages 41, the precise installation position of the lower roller trains 21u, 22u and 23u, i.e. the distance between the carriages 41, being adjustable by means of corresponding screw bolts or the like.

The machine-long lower roller strands 21u, 22u and 23u are generally each composed of a large number of roller segment pieces which are each equipped with a structure 40 in the area of their working surfaces. The bottom roller strands 21u, 22u and 23u are also, as in 3 shown, can be driven in a defined manner via a drive device 27 arranged at the end of the machine. That is, the sub-roller trains 21u, 22u and 23u are via a reduction gear 29, the z. B. is designed as a change-wheel drive, so connected to an electric motor drive 28 that the speed of the lower roller strands 21u, 22u and 23u can be predetermined. Both the draft value of the pre-draft zone 35 located between the input roller pair 21 and the middle roller pair 22 and the draft value of the main draft zone 36 arranged between the middle roller pair 22 and the output roller pair 23 can be set in a defined manner via the speeds of the lower roller strands 21u, 22u and 23u.

How out 2 further visible, a support 45 is fixed to the punch 9 via a holding rod 16, on each of which a pendulum support 26 and a loading arm 17 of the drafting system 10 are mounted. As is known, the top rollers 21o, 22o and 23o of the drafting system 10 are mounted on the pendulum support 26 via corresponding holding elements (not shown) in pairs.

3 shows a schematic plan view of the bottom roller strands 21u, 22u, 23u of the drafting units 10 of a ring spinning machine 1.

As already indicated above, these lower roller strands 21u, 22u, 23u each consist of a large number of roller segments 34, 48, etc., which are connected to one another in a torque-proof manner. The lower roller strands 21u, 22u, 23u are mounted at regular intervals in punches 9 and are driven by a drive device 27 which is arranged on the machine input side and which, e.g. B. via an electric motor 28, which is supplied from the network 44 with energy, and a reduction gear 29 has applied rotationally. This means that the lower roller strands 21u, 22u, 23u are positively and non-positively connected to one another by the interchangeable gear train of the reduction gear 29 .

In the present exemplary embodiment, a further drive device 46 is also arranged on the side of the ring spinning machine 1 opposite the drive device 27, the gearing 37 of which is also coupled to the lower roller strands 21u, 22u, 23u.

The transmission 37, which is intended to ensure that the speeds of the lower roller strands 21u, 22u, 23u remain precisely matched to one another, can also, as indicated, be acted upon by an electric motor 47.

The lower roller strands 21u, 22u, 23u are also each equipped, approximately in the area of the machine center 30 of the ring spinning machine 1, with length compensation devices 31 designed according to the invention. This means that the length compensation devices 31 are designed and arranged in such a way that, with respect to the lower roller strands 21u, 22u, 23u, both a transmission of torques and a heat-related length compensation are possible.

The exact embodiment of a length compensation device 31 designed according to the invention is described below with reference to FIG figures 4 , 5 and 6 explained in detail.

4 shows, in a slightly perspective view, the middle section of a lower roller strand 21u of a drafting system 10 of a ring spinning machine 1.

As is known, such a lower roller train 21u consists of a large number of roller segments which are connected to one another in a rotationally fixed manner before they are installed. Such a lower roller strand 21u has, for example, as shown in FIGS Figures 3 to 6 shown, among other things via central roller segments 34, 48, between which a length compensation device 31 is switched on, which is designed according to the invention as follows.

The length compensation device 31 is in an advantageous embodiment, for example figure 5 can be seen from a balancer shaft 38, a bearing sleeve 39, a lower roller bearing 42 and connecting pieces 43. The balancer shaft 38, which has a so-called P4C polygon profile and is preferably surface-hardened, is fixed in a bearing sleeve 39 when installed, which in turn can be rotated in a lower roller bearing 42 is positioned, which is mounted on a punch 9, which is preferably arranged approximately in the area of the machine center 30 of the ring spinning machine 1.

In the assembled state, the in 6 is shown, the balancer shaft 38 corresponds to connecting pieces 43, which in turn are fastened in the roller segments 34, 48, for example by means of a press fit. This means that the connecting pieces 43 each have a central, preferably likewise surface-hardened receptacle 49, which is adapted and matched to the P4C polygonal profile of the balancer shaft 38 in such a way that the 43 and thus the roller segments 34, 48 can be displaced axially on the balancer shaft 38 .

Such an axial displacement of the connecting pieces 43 on the balancer shaft 38 always occurs in particular when there is a thermally induced longitudinal expansion of the lower roller strands 21u, 22u and 23u. Since the P4C polygonal profile also enables problem-free transmission of relatively large torques, the operation of the ring spinning machines is affected by such longitudinal expansions of the lower roller strands 21u, 22u and 23u not disturbed.

As already described above, no notch effects occur with P4C polygonal profiles when torque is transmitted, so that P4C polygonal profiles have a 30% higher fatigue strength than conventional splined shaft profiles. <b>Reference List</b> 1 ring spinning machine 24 deflection rod 2 pedestal 25 movement mechanism 3 standpipe 26 pendulum beam 4 suction channel 27 drive device 5 bridge piece 28 electric motor 6 support tube 29 reduction gear 7 ring spinning spindle 30 machine center 8th spinning cop 31 length compensation device 9 punch 32 boom 10 drafting system 33 Bobbin changing device 11 support tube 34 roller segment 12 template material 35 advance field 13 support column 36 main zone of delay 14 template material gate 37 transmission 15 template spool 38 balance shaft 16 handrail 39 bearing sleeve 17 Low-impact 40 structuring 18 ring bank 41 Sleds 19 balloon constriction ring 42 bottom roller bearing 20 thread guide 43 fitting 21h bottom roller strand 44 network 21o top roller 45 support 22u bottom roller strand 46 drive device 22o top roller 47 electric motor 23u bottom roller strand 48 roller segment 23o top roller 49 Recording

Claims (8)

1. Ring spinning machine (1) having drafting systems (10), which are formed by roller pairs (21, 22, 23), which rotate at different peripheral speeds and have bottom roller lines (21u, 22u, 23u) running the length of the machine, which are formed by partially ribbed roller segments (34, 48) and are each equipped with a length compensation device (31),
   characterised in that

   the length compensation devices (31) incorporated in the bottom roller lines (21u, 22u, 23u) are each designed and arranged in such a way that, with respect to the bottom roller lines (21u, 22u, 23u), both length compensation and torque transfer are possible, the length compensation devices (31) comprise a compensation shaft (38) and a receptacle (49) which form a positive shaft-to-hub connection, and

   the roller segments (34, 48) of the bottom roller lines (21u, 22u, 23u) are each axially slidably connected to the compensating shaft (38) by means of the receptacle (49).
2. Ring spinning machine (1) according to claim 1, characterised in that the compensation shaft has a P4C polygon profile.
3. Ring spinning machine (1) according to claim 1, characterised in that the compensation shaft is designed as a multiple spline shaft that corresponds with associated inner centring means in the receptacle (49).
4. Ring spinning machine (1) according to one of claims 1 to 3, characterised in that the compensation shaft (38) is rotatably mounted in a bottom roller bearing (42) by means of a bearing sleeve (39).
5. Ring spinning machine (1) according to one of claims 1 to 4, characterised in that the roller segments (34, 48) of the bottom roller lines (21u, 22u, 23u) each have a connection piece (43) with the receptacle (49).
6. Ring spinning machine (1) according to claim 5, characterised in that the connection pieces (43) are each fastened in one of the roller segments (34, 48) of the bottom roller lines (21u, 22u, 23u) in a rotationally fixed arrangement by means of a press fit.
7. Ring spinning machine (1) according to one of claims 4 to 6, if dependent on claim 4, characterised in that the bottom roller bearing (42) is supported on a die (9), which is arranged approximately in the area of the machine centre (30) of the ring spinning machine (1).
8. Ring spinning machine (1) according to one of claims 4 to 7, if dependent on claim 4, characterised in that the bottom roller bearing (42) is designed in such a way that the bearing sleeve (39) fitted with a compensation shaft (38) can be inserted from above into the bottom roller bearing (42), which can be folded open, and that the bearing sleeve can be locked in the bottom roller bearing (42).

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