Title of Invention

RING SPINNING MACHINE WITH SPINDLE PRE-RUNNING

Abstract

Method for the control of a ring spinning machine after the completion of a cop (10) and before the renewed switching on of the drive of the spindle (20) or the drafting arrangement (40), the yarn (100) being laid in an underwinding (104) on the circumference of the spindle (20) and held by means of a thread guiding device (30) on the circumference of the spindle by means of a traveller (303) on a spinning ring (302),characterized in that before the rapid start of the spindle (20) for the production of a fresh winding (102) on a freshly pushed on tube (201.) the spindle (20) is rotated in slow running in the normal direction of rotation of ,the spindle, the speed of rotational movement of the spindle (20) and the duration of this operation being so select,ed that the traveller (303) is positioned on the spinning ring (302) in the direction of rotation of'the spindle (20) behind the starting of the yarn (100) on the circumference of the spindle (20), the traveller, at the latest with the termination of the slow running, being brought into the required sloping position (Fig.3) for the subsequent starting of the winding of a new tube (201). ID a ring spinning machine, after the doffing operating the spindle (20) is further rotated at a slow speed in the normal direction of rotation, through which the twist in the yarn(lOO) between the spindle (20) and the drafting arrangement (40) is tensioned and the traveller (303) is brought into the required position for the subsequent start. Through this, the traveller takes up a defined and reproducible position on the spinning ring (302), so that, with the subsequent starting of the spindle (20) or the drafting arrangement (40), the thread ballon (105) can he built up in an orderly way without engendering thread breaks when starting. PRICE :THIRTy RUPEES

Full Text

The invention relates to a ring spinning machine. With ring spinning machines, a disadvantage exists because of the fundamental system in that a number of cops must be removed after winding, for which purpose the spinning machine must be stopped. When restarting the spinning machine, yam breaks can occur, which, according to the limiting conditions, can be regarded as more or less frequent. According to the counter measures which can be adopted to prevent the breaking of the yam after a spinning start, the method described in the DE-Al-4234832.3 (obj.2353) belongs as an example. With this, the ring rail on the lowest position is next raised slightly and then rapidly lowered, in order to straighten a so-called curling in the yam, so that this cannot cause a disturbance. Yam breaks when starting the spinning machine after doffing can also be caused in that the movement of the traveller on the spinning rail is insufficiently adapted. After the spindle has been switched on and during the acceleration operation, the traveller should move in a circular path round the spinning rail in the correct relationship to the rotation of the spindle, with which it remains sufficiently far form the respective starting point of the yam on the periphery of the spindle so that the yam delivery from the drafting arrangement can be wound on to the spindle. When the traveller, after the start of the machine, slides too quickly on to the spinning rail, for example with the rotational speed of the spindle, or even revolves more rapidly iban. the spindle, then no yarn, or insufficient yarn, is wound on to the spindle, so that the delivery from the drafting arrangement causes an enlargement of the yarn balloon. When the yarn balloon has reached a predetermined size, then the centrifugal force is too great and causes a yarn break. It is valid to improve the relationship from the start of the machine so that the traveller is located in a position which is as stable as possible and, with conditions remaining constant after the start of the machine, is carried along from the spindle with the connecting piece of yarn. This objective is reached is with the method according to the characteristics of the first independent claim. A suitably equipped' spinning machine has the characteristics of the independent claim 7. The dependent claims relate to the preferred method characteristics in detail. Through the method according to the invention and with the corresponding control of the spinning machine, consistent conditions can be attained with the machine start after doffing, with which the yarn breaks caused by the system only appear very infrequently. Accordingly the present invention provides a ring-spinning machine comprising a spindle, a controllable drive for driving said spindle, a thread guide device, an independent drive for driving said thread guide device, a drafting arrangement, a drive for driving said drafting arrangement, the said drives being connected via supply leads to a control, and a processor coupled with said control, wherein said processor has an input unit for the alteration of the setting parameters. In the following, the invention is explained in detail with the aid of the accompanying drawings. It is shown Fig. 1 A schematic survey of the most important drives of the spinning machine. Fig. 2 A detailed view of a cop with a part of the thread guiding device. Fig. 3 A partial view of a spinning rail with traveller and a tube with a yam winding. Figs Aa and Fig,Ab Positions of travellers on the spinning rail dependent on the thread tension. Fig.5 A diagram of the progress and type of the rotational speed or the positions of machine drives over the time, with HR for the stroke of a ring rail and NS or NL for the rotational speed of the spindle and the drafting arrangement. In Fig.l, a spindle 20, which is seated in a bearing 203 of the ring spinning machine and an encircling thread guiding device 30 are shown in a simplified way. The spindle 20 is driven over a belt 204 and a disc 205 by a motor 210 with the necessary driving power. The thread guiding device 30 is suspended on a tension medium 30A, the end of which is fastened on a disc 305. This is coupled with a motor 310 or another mechanical drive. The yarn 100 forms a thread balloon 105 with the rotation of the spindle 20 according to the arrow near 20, which is limited on the one hand through a traveller 303 and on the other hand by a thread guide 101. The yarn 100 is fed to the thread guide 101 through a drafting arrangement 40 whose fibres originate from a receiver unit and are further transported by a roller 401, amongst other devices. This roller is in contact with a further motor 402 via a gear box. The motors mentioned are supplied with electrical energy via leads 502 from a control 50. There is a processor 501 on the control 50, connected with an input unit, by means of which different setting parameters can be altered for the drive of the ring spinning machine according to the operating conditions. The driving means necessary for the operation of a ring spinning machine for carrying out the method according to the invention are described in the German Patent Specification DE-Al-4234832.3. Fig.2 shows a cop 10 in detail as a section of Fig.l, which consists of a tube 201 and a winding 102 of yarn 100 and which is pushed on to a spindle 20 . The thread guidance device 30 consists of a ring rail 303 and a spinning ring 302 fastened to it, which encircles the spindle 20 concentrically. A traveller 303 is seated on the spinning ring 302, through which the yarn 100 is guided around the spindle 20. In Fig 2, the situation shortly before the so-called doffing operation is shown, with which the cop 10 on the spindle is pulled off and passed to a transport system. After the winding 102 on the tube 201 is finished, the ring rail 301 is located in the uppermost position on the upper end of the winding 102. The ring rail is then rapidly moved downwards in the period of time between T2 and Tl according to Fig.5, the yarn being wound steeply downwards around the cop 10 in the so-called reserve winding 103. The ring rail 301 is thereby lowered so far that the traveller lies underneath a crown 202, which should determine the position of the yarn on the circumference of the spindle 20. In this position, the ring rail 301 remains with the spinning ring 302 on the same height as the underwinding 104 and the traveller 303, so that, with a slower rotation of the spindle 20, yarn is wound on to the spindle 20 in the so-called underwinding 104. Up to 4 windings are placed on the spindle. This takes place in the period of time between T2 and T3, according to Fig.5. The position of the ring rail 301 can be taken from the path of the line HR . During this phase, the spindle 20 and the drafting arrangement 40 come to a stop, which can seen from the lines NS or NL according to Fig.5. Subsequently, in the period of time between T4 and T5 according to Fig.5, the ring rail 302 is again lifted up to the position shown in Fig.2, in which it remains stationary during the period of time between T5 and T6'. Thereby, yarn 100 is wound a second time over the crown 202, so that the yarn position on the spindle 20 is ensured. Now, the finished cop 10 can be removed from the spindle 20, through which the reserve winding 103 and the underwinding 104 breaks at about the height of the crown 202, as it is hanging there in a serration. The remaining yarn, namely the underwinding 104 and the piece of the yarn 100 above it, remain on the spindle. According to the invention, the spindle 20 is now further rotated slowly with a reduced level of rotational speed NS' according to Fig 5, between the periods of time T6 and T5'. The delivery from the drafting arrangement 40 is not yet switched on. This has the result, that the part of the yarn between the underwinding 104 and the drafting arrangement 40 are twisted further, through which the traveller 303 continues to move with the movement of the spindle. The yarn tension increases slightly and the traveller, with this slower spindle rotation, takes up a position as shown in Fig.4a or Fig,4b. Because of the tension in the yarn 100 and the movement of the spindle 20 in the normal winding direction, according to the arrow in Fig.3, the traveller 303 lies in a sloping position and is lifted by the tensioned piece of thread. With this, the traveller 303 supports itself below on the spinning ring 302, so that it is in a stable position, contrary to the position in Fig.4b. Contrary to this, the traveller can take up the position shown in Fig.4b, without the slow spindle rotation after the doffing operation, because the piece of the yarn 100 is only tensioned weakly or is loose, through which the subsequent switching of the spindle drive of the traveller can take up a speed which is too fast and does not remain far enough in relation to the spindle rotation, which can lead to yarn breaks, as described at the outset. Through the relatively simple expedient of the slow rotation of the spindle, the yarn-traveller system is stabilized in such a way, that after the final switching on of the Obj:^483A spindle drive 20 after the point of time T8 according to Fig.5, can build up the thread balloon 105 in an orderly way. As is known from the DE-Al mentioned at the outset, a so-called curl removing movement of the ring rail 301 can then follow after the points of time T6' and T9, whilst the drive of the spindle 20 and the drafting arrangement AO is switched on at the earliest point of time T8 according to Fig.5. The curves NS and NL, after the point of time T8 in Fig.5, show the progress of the rotational speed of the spindle 20 or the drafting arrangement AO. The ring rail is gradually lifted in pilgrim step movements from the point of time T9 according to Fig.5 and according to the stroke curve HR, whilst the drive of the spindle 20 or the drafting arrangement AO are accelerated to their maximum rotational speed. The following setting parameters have shown to be satisfactory: The progress of the acceleration of the spindle 20 is to selected in such a way that a starting acceleration of 100 l/s2 results, which means that, within the first seconds after the starting the drive of the spindle 20, a rotational speed of 6000 r.p.m is reached. The temporary braking of the spindle from the point of time Tl up to the point of time T2 according to the branch of the curve NS in Fig.5 should not result too slowly. Here, a braking delay of >1A l/s2 can be regarded as suitable. Whilst the slow running of the spindle 20 between the point in time T6 and T6' according to the course of curve NS' in Fig.5 brings the spindle 20 up to two revolutions, whereby a rotational speed of 0.5 to two revolutions per second is recommended. The slow running of a spindle does not end positively with the beginning of the curl removing stroke of the ring rail 301 from the point in time T6. The slow running of the spindle 20 can be deferred until shortly before the point in time T8, according to Fig.5, by switching the spindle 20 to fast running. WE CLAIM : 1. A ring-spinning machine comprising a spindle (20), a controllable drive (210) for driving said spindle, a thread guide device (30), an independent drive (310) for driving said thread guide device, a drafting arrangement (40), a drive (402) for driving said drafting arrangement, the said drives (210, 310, 402) being connected via supply leads (502) to a control (50), and a processor (501) coupled with said control (50), wherein said processor (501) has an input unit for the alteration of the setting parameters. 2. A ring spinning machine substantially as hereinabove described and illustrated with reference to the accompanying drawings.

Documents:

217-mas-95 abstract.jpg

217-mas-95 abstract.pdf

217-mas-95 claims.pdf

217-mas-95 correspondence-others.pdf

217-mas-95 correspondence-po.pdf

217-mas-95 description (complete).pdf

217-mas-95 drawings.pdf

217-mas-95 form-1.pdf

217-mas-95 form-26.pdf

217-mas-95 form-4.pdf

217-mas-95 others document.pdf