DE4328417A1 - Start up method for ring spinning machines - relates start of yarn delivery and traverse movement to balloon size to reduce end breaks - Google Patents

Abstract

A ring spinning machine has a drive and control mechanism for the various components so that during start up the delivery of yarn (11) from the drafting system (6) is related to the growth of the yarn balloon. Pref. a ring spinning machine has spindle driven by individual motors (10) and drives (14) for the ring rail (4). Sensor lines (19,20,21) provide performance feed back to a controller (22) with a data store (18). The start up procedure is tailored to the conditions in which the machine as shut down and programmed or emergency shut downs are treated similarly. The ring rail is first moved a small distance from its last position to straighten out any yarn loops. The spindles are then started to build up the yarn balloon with no yarn delivery and a stationary ring rail, so that twist is inserted to strengthen the yarn. Yarn delivery and traverse motion is started once the balloon is fully established. USE/ADVANTAGE - For reducing end breaks during starting of ring spinning machines, esp. after an unscheduled stop. Removes yarn loops from threadline and inserts extra twist before starting traverse motion.

Description

The present invention relates to a method for starting a ring spinning or twisting machine according to the preamble of Claim 1.

Ring spinning machines of the type mentioned have a height-adjustable ring frame, which is the winding of the Spinning sleeves allowed over the desired height. In the ring frame drive is an eccentric, usually called a heart eccentric, provided, which on a between drive and ring frame provided transmission member acts. This overlays the basic movement of the ring frame another back and forth Moving with a higher frequency and a smaller amplitude, which leads to the winding of the cop.

If a ring spinning or twisting machine is started, kick often thread breaks on:

Once, when the machine is switched off, squiggles form, he testifies by the twist between the drafting system and the runner sagging thread. When starting again, these can Squiggles get caught in the runner, causing the passage of the thread prevents and leads to breakage.

On the other hand, the runner is before starting again possibly in an undesirable position for the operation. When starting again, the runner can then on the spinning ring tilt what slows him down or the passage of the thread disturbs; both increase the risk of the thread breaking.

Third, lies through during the construction of the thread balloon the increasing centrifugal force and, depending on the stage in Structure of the winding or the thread material etc., a increased stress in the thread, hence increased risk of breakage in front.  

According to the prior art it is known that the start of the Machine can be done with little risk of breakage if the following boundary conditions exist:

The start must be from the heart-pointed position; correspond The ring frame moves downwards in the start phase. The winding thus runs to larger diameters, what for the strain on the thread during balloon build-up is advantageous is imprisoned.

Next, immediately after the start, a downstairs dish is served Additional stroke of the ring frame triggered. This will make the existing curling slowly, the additional lifting speed undressed accordingly. The strain on the thread lasts itself in the frame, because spindle shaft rotation and delivery either haven't started yet or are still on deep who be driven.

In fact, however, the following marginal conditions are predominant given:

After changing the cops, the ring frame is in the lower one Dead center, regardless of the position of the heart. The downward Movement to larger diameters is not possible, which is why leads to thread breaks occurring when starting.

After an emergency shutdown, i.e. H. a deliberate interruption, there is any heart position. When restarting is the risk of thread breaks occurring is high.

Favorable conditions are however present at the "after-work-off" den: The parking can be done so that at machine is in a cardiac-pointed position. With that lie the above-mentioned favorable boundary conditions. The start takes place with an acceptable risk of thread breaks.  

Unintentional parking of the machine has occurred a power failure, after defects etc. As with the "emergency stop" then there is a random position of the heart, which means that given a probability of two thirds is that the ring bench at the new start up instead of moving down.

In summary, there is a considerable risk for thread breaks at the start of the spinning machine.

It is an object of the present invention to overcome these disadvantages overcome and a method of starting a ring spinning or To create twisting machine in such a way that a significantly reduced There is no risk of thread breaks during the starting process.

To achieve this object, the Ver drive the characteristic features of claim 1.

At the beginning of the spindle shaft rotation in the start phase increases the stress in the thread due to the balloon building up at. As long as the delivery of new thread is not possible the ring frame must be kept at a constant height; a wide one re winding of the cop is not yet taking place. So runs also no thread through the runner, which means that a further burden from the run through the runner, be it by unstretched curls, or by raised ones Thread friction on the unfavorably positioned runner, does not occur.

The only by the centrifugal force in the thread balloon building up given load exceeds the critical limit for the Do not damage the thread. It also grows with the bigger balloon with the twist in the thread, which results has that the strength of the thread parallel to the greater increasing centrifugal force.  

It turns out that from a certain stage in the balloon the conditions have become so favorable that the drafting system switched on and thus the delivery of the company dens can be triggered without causing the Excessive stress causes thread breaks.

In addition to solving the task, it follows not only an essential by the inventive method more favorable average risk of thread breaks. There is no NEN parking mode more such. B. "Emergency stop" where an increased Risk of breakage is inevitable.

In a preferred embodiment, it starts delivery after the assembly of the thread balloon. Of the Thread then has a maximum twist, thus a maxi Male strength for the stress by which now begin the thread run through the runner. Any remaining Squiggles are drawn by the runner without damage. Exactly so an unfavorable, z. B. jammed runner the unbreakable twisted thread in its low-friction operation position pulled.

In another embodiment according to claim 12, the Spindle shafts, as is common in the prior art, by an asynchronous motor fed by a frequency converter driven. The drafting system, however, is according to the invention one operatively connected to the same frequency converter NEN reluctance motor driven, which allows the drafting system according to the provision of claim 1 at a time switch where the spindles are already in operation. In addition to solving the task, it follows through this arrangement the required, quick start of the Drafting system up to the delivery speed to be met exactly speed, while the design effort for the execution of the The method according to claim 1 remains minimal: Another Fre  quenzumformer for the control of the drafting motors, wel driving your own speed program is not necessary.

Further embodiments have features of the dependent appendix say on.

An exemplary embodiment is described below with reference to the figures described in more detail.

It shows:

Figure 1 schematically shows a cross section through a ring spinning or twisting machine for performing the method according to the invention.

Fig 2-4 the launcher according to the present invention after an interruption to general position in the winding of a cop. and

Fig. 5-7 the launcher according to the present invention after a cop change;

Fig. 8a and b schematically from the start program preceding setting programs for the spindle shafts and the drafting system;

Fig. 9 shows schematically the structure of the ring frame control with an eccentric heart; and

Fig. 10 schematically shows a machine layout in which the drafting mechanism is driven by a reluctance motor.

Fig. 1 shows a cross section through a ring spinning or twisting machine 1. A frame 2 , a spinning unit 3 , a ring frame 4 and an area 5 of the upper part of the frame 2 are shown .

The spinning unit 3 has a drafting system 6 , a spindle shaft 7 and a spinning ring 8 arranged on the ring frame 4 , on which a rotor 9 runs. The spindle shaft 7 is mounted in a single spindle shaft motor 10 .

Together, the spindle shaft 7 , the spinning ring 8 and the rotor 9 form a thread guiding device for a thread 11 which is drawn off from a processing spool 13 hanging from a holder 12 .

Also shown is a drive 14 for the ring frame 4 with an intermediate transmission member 15 .

A data processing unit 17 has a memory 18 for a start program according to the present invention and is operatively connected to sensor lines 19 , 20 and 21 for manipulated variables relating to the position of the ring frame 4 , the spindle shaft speed and the delivery speed of thread 11 from the drafting system 6 .

For its part, a control unit 22 is operatively connected to the data processing unit 17 , also operatively connected to control lines 23 , 24 and 25 for the drives of the ring frame 4 , the spindle shaft 7 and the drafting unit 6 .

Fig. 2 shows a diagram in which the height of the ring bench 4 is plotted over time t. According to the range of motion of the ring bench 4 are marked on the abscissa, the underwind position UW, the upwind position OW, the piecing position ANS, the upper reversal point and the lower reversal point OU, UU for the winding of a Kötzer position; the upper reversal point in the start phase OU _ST and the lower reversal point in the start phase UU _ST for the winding during the start phase as well as the starting height of the ring bench H _ST and the height of the ring frame 4 after the interruption in the winding H _UN .

The ordinate denotes the start time t1, which initiates an additional stroke of the ring frame 4 . t2 denotes the time at the end of the additional stroke and the start of a return movement of the ring frame 4th t3 marks a period at or shortly after the start of the return movement. t4 is the time that is given as soon as the return movement has ended.

Instead of the extended additional stroke Zh leading upward, a downward additional stroke Zh according to the dashed line is also conceivable. This is used when the upward additional stroke Zh would lead beyond the upper wind position, since the starting height H _{ST is} too high. The return movement then leads upwards accordingly.

In the period t4, t5, the height of the ring frame 4 remains constant. In the time between t5, t6 and t7, t8 the ring frame 4 is moved upwards and in the time between t6, t7 and t8, t9 downwards.

FIG. 3 is a diagram in which the spindle shaft speed is plotted as a function of the time t. According to the diagram in FIG. 3, the spindle shaft 7 is only set in rotation at time t3 and further accelerated after reaching a first speed n1.

FIG. 4 shows a diagram in which the delivery L of thread 11 from the drafting device 6 is plotted over time. At time t5, the delivery is immediately increased to a minimum value L1 and then ramped up further.

FIG. 5 shows a diagram corresponding to the diagram of FIG. 2, the height of the ring bench being plotted against time at the start after a cop change. The names of the abscissa and ordinate correspond to those of FIG. 2.

FIGS. 6 and 7 show the diagrams of Figs. 3 and 4, the spindle shaft speed and the delivery speed in dependence on the ring frame position in FIG. 5 are gen aufgetra.

Fig. 8a and b schematically show a run-out diagram for the machine of Fig. 1: In Fig. 8a, the drafting machine speed n _St compared to that of the spindle shafts later, but reduced proportionally, which has the consequence that the thread reserve in the thread ball lon the cop wound up, a sagging of the thread - and thus the curling - is reduced when the machine is at a standstill, so that the risk of thread breakage decreases further.

In Fig. 8b, conversely, the spindle shaft speed is reduced proportionally, which in particular with higher twisted yarns leads to the sagging thread being less twisted, ie less prone to curling.

The disproportionate reduction in either the spindle shafts speed or the drafting system speed should be at least during a phase of the stopping process is done to sag or to achieve a high twist of the thread; according to Be A speed may still be allowed in a first phase be kept constant while the other is already sinking.

Fig. 9 shows schematically the ring frame drive of the machine of Fig. 1, wherein the basic drive is an additional drive overlaid. The basic drive consists of the motor 60 and the flexible tension member 61 , which runs over different rollers 62 and is anchored to a return spring 63 for the desired back and forth movement. The additional drive has a motor 65 , which acts on a heart-shaped eccentric 66 . The eccentric 66 in turn acts on the pivot beam 68 mounted on the roller 67 , so that the roller 69 supporting the tension member 61 of the arrow direction moves back and forth accordingly. In the tension member 61 , the movements of the basic drive, ie the motor 60 , and the additional drive, ie the eccentric 66 , add up, the total movement via the axis 70 to the roller 71 and from there to the transmission member 72 , thus to the ring frame 4 transmits. The overall movement allows the application of a Kötzerbewick treatment on the cop 7 '. The bearings 73 are located in the frame 2 of the machine 1 .

Fig. 10 shows schematically the drafting devices 6 or the cylinder 70, 71 and 72. The cylinders are driven by a reluctance motor 74 via a gear 73 .

The schematically indicated spindle shafts 7 have a common asynchronous motor 75 , which is fed via a frequency converter 76 .

The reluctance motor 74 is also fed by the frequency converter 76 , a switch 77 being provided in order to switch on the supply only when the drafting system according to the present method is to be started to start the machine. The reluctance motor 74 is able to start up at the frequency specified by closing the switch 77 and to follow it synchronously, which makes it possible to save a frequency converter operating the draft mechanism drive.

At the beginning of the starting phase, the data processing unit 17 activates the drive of the ring frame 4 via the control line 23 , so that it is brought from the starting height h _ST to the height Z or Z '. As a result, squiggles are drawn out of the thread sagging between the stretching unit 6 and the spinning ring 9 . On closing the ring frame is driven by a return movement R h _un back to the height; the data processing unit 17 has the previous height, the height h _un , the ring frame 4 determined and saved at the termination of the previous winding on the sensor line 19 , so that intervening manipulations can not affect the resumption of the winding of the cop.

Once the height h _{un is} reached, the data processing unit 17 activates the spindle shaft drive 10 via the control line 24 , so that the thread 11 sagging between the drafting system 6 and the spinning ring 9 is twisted and assembled into a thread balloon. The spindle shaft speed is accelerated as a function of the thread material, as a rule, after reaching a first speed n1, a slower acceleration is appropriate because the thread load increases disproportionately as the radius of the thread balloon increases. The progressive twisting causes the thread to be reinforced in parallel.

At time t5 the thread balloon is completely assembled; the data processing unit 17 switches on the control line 25, the drafting system 6 and via the control line 23, the ring frame drive, whereupon the delivery of thread 11 from the drafting system 6 and the working stroke of the ring frame 4 are carried out.

In FIG. 2, the working stroke takes place 4 of the ring frame to the time t6 to the top; this is a continuation of the situation in the winding process that started in the winding before the interruption. The Da processing unit 17 thus saves not only the height h _{un of} the ring frame, but also its direction of advance when interrupted in the winding.

After reaching the height ou _st , the winding layer which has only begun when the winding is interrupted is completed, so that a new layer can be started at time t6.

The procedure described above ensures that after completion of the winding layer at time t6 Winding interruption essentially no longer found can be. Despite interruption at any time in the Be winding is thus essentially the structure of the cop disturbs. Another Kötzerlage can in the period from t7 to t9 be applied without the interruption of wrapping would impact.

Fig. 5 shows a start program for starting after changing the cop. This launcher is basically the same set builds, as the program of FIG. 2. However, there is the interruption in the winding no general h _un where the Kötzerlage has been interrupted un. After changing the cop, the ring frame 4 is in the downwind position UW. Accordingly, it is only brought up to a height Z for pulling out curls. The spindle shaft speed is ramped up by the data processing unit 17 at a time t10, where the ring frame 4 is still in the return movement. The balloon is then built up at a favorable height h, depending on the thread material. At time t11, the winding is then started, ie the delivery of thread 11 from the drafting system 6 is activated.

As already mentioned, the special feature of the method according to FIGS. 5-7 is that the ring frame is in the downwind position after changing the cop; there is therefore no height h _un or feed direction, which is to be taken into account by the data processing unit 17 in the starting phase. A value h is used for h _un and the upward feed is used by default for the feed direction.

In high-speed spinning machines with an operating speed above approx. 18,000 rpm, there is a tendency to use lighter runners so that the thread tension is not too great. On the other hand, a stable thread balloon, which prevents the so-called starting thread breaks, requires a minimum tension in the thread. It can be assumed that the construction of the balloon is complete when a tension of 10% of the breaking tension of the thread is reached in the thread. In order to achieve this, a run-up of less than 30 mg should be started with an angular acceleration of the spindles 1 / sec ² .

Claims (12)

1. Method for starting a ring spinning or twisting machine with a frame, a drive (A) and a controller (S) for organs to be moved, with a ring frame and spinning or twisting units, each with a drafting device and a thread guide device each have a spindle shaft for a sleeve to be wound into a cop and each have a rotor arranged via a spinning ring on the ring frame, characterized in that in the starting phase the delivery of thread ( 11 ) from the drafting device ( 6 ) depending on the structure of the thread balloon he follows. 2. The method according to claim 1, characterized in that the delivery of thread ( 11 ) is switched on after the assembled Fa denballon. 3. The method according to claim 1, characterized in that an additional stroke (Zh) of the ring frame ( 4 ) takes place depending on the structure of the thread balloon. 4. The method according to claim 3, characterized in that the additional stroke (Zh) takes place before the thread balloon is set up. 5. The method according to any one of claims 1 to 4, characterized in that the delivery of the thread after a Rückbe movement (R) of the ring frame ( 4 ). 6. The method according to claim 5 for starting after an interruption in the winding of the cop ( 16 ), characterized in that the ring frame ( 4 ) by the return movement (R) is placed at the location where the winding of the cop ( 16 ) has been interrupted. 7. The method according to claim 1 for starting after a cop change, characterized in that the ring frame ( 4 ) by the return movement (R) in the piecing position (ANS) is set. 8. The method according to any one of claims 3 to 7, characterized ge indicates that the additional stroke (Z) upwards at a starting position above a predetermined height (has) done down. 9. The method according to any one of claims 1 to 7, characterized in that a stopping process preceding the starting of the machine has at least one phase in which the speeds of the spindle shafts ( 7 ) and the drafting device ( 6 ) are not reduced proportionally, such that that after the discharge has taken place, either the sag of the thread in the spinning unit ( 7 ) is reduced or the thread ( 11 ) is twisted to an increased extent. 10. Control for a ring spinning or twisting machine for performing the method according to one of claims 1 to 8, characterized by a data processing unit ( 17 ) with memories ( 18 ) for in particular a starting program for the machine ( 1 ), which with control lines ( 22 , 24 , 25 ) for the drive and with sensor lines ( 19 , 20 , 21 ) for manipulated variables of at least the ring frame ( 4 ), the spindle shaft ( 7 ) and the drafting system ( 6 ) can be operatively connected. 11. Control according to claim 9, characterized by a ziges start program according to one of claims 1 to 8. 12. Ring spinning or twisting machine for performing the method according to one of claims 1 to 9, characterized in that the drive (A) for the spindle shafts an Asynchronmo gate ( 40 ) and for the drafting device a reluctance motor ( 45 ) and the controller ( S) have a common frequency converter for the asynchronous motor ( 40 ) and the reluctance motor ( 45 ).