GB2128213A - Thread store - Google Patents

Description

1 GB 2 128 213 A 1

SPECIFICATION

Athreadstore The present invention relates to a thread store with a70 rotary drive mechanism as well as a storage roll which can be driven by this rotary drive mechanism, to whose feed end the thread can be fed approximately tangentially from a feed point and from whose discharge end the thread can be taken off against the 75 action of a retaining element through a thread guide arranged in an extension of its axis.

Thread stores of this type are known in a wide variety of designs (German Offenlegu ngssch riften Nos. 2,555,802 and 2,607,460). The thread is invariably 80 fed tangentially to the storage roll, loops it several times and leaves the storage surface in an axial direction between storage roll and a retarding ring placed on its discharge end, forwhich purposethe thread has to be guided through an annularthread guide. Such thread stores are used in yarn-processing machines such as hosiery, knitting and weaving machines (German Offenlegungsschrift No. 2,555, 802), but also in yarn-producing machines, in particu lar open end spinning machines (German Offenle gungsschriften Nos. 2,553,892 and 2,717,314). These known devices all have the disadvantage thatthe thread has to be threaded into the retarding ring and into thethread guide in a complicated fashion, which istime consuming and necessitates a stationary arrangement of thethread store even if storage is only needed temporarily.

The object of the present invention istherefore to provide a thread store of the type mentioned atthe outsetwhich enablesthe thread to be broughtto the thread store in a simple manner. Afurther object of the invention isto develop the thread store in such a way that it can be brought into thethread course merely temporarily without interrupting the thread travel and can storethethread.

This object is achieved according tothe invention in thatthe storage roll has a retaining elementwhich is open radially outwards and can be driven and in that thethread guide can be opened and closed. To enable the retaining elementwhich is open radial ly outwards 110 to be driven, a retaining force is always applied to the thread during take-off to preveritthe thread from being taken off the storage roll in an uncontrolled fashion. This retaining force enables the retaining elementto be open radial ly outwards in design, avoiding complicated threading of the thread. The possibility of opening and closing the thread guide also avoids a complicated threading procedure. This design of retaining element and thread guide enables a continuous thread to be placed on the thread store 120 fortemporary storage and then to be released again completely bythe thread store.

The retaining elementwhich is driven and is open radially outwards can be designed in various ways.

According to a design which is mechanically extreme- 125 ly simple, the retaining element consists of the circumferential area of the storage roll which is provided with a plurality of openinbs merging into the interior of the storage roll which, in turn, is connected to a vacuum source.

The reduced pressure acting on the thread through the openings in the circumferential area of the storage roll cause the take-off force exerted from the discharge side of the storage roll on thethread to be countered byan opposing forcewhich prevents the thread from leaving the storage roll in an uncontrolled fashion. The openings are preferably designed as slotswhich extend essentially over the entire storage length of the storage roll asthethread windings can always be retained well on the storage roll in I"way and can be produced in a simple fashion independently of the position of the individual thread windings collected on therstorage roll.

To improvethe retaining effectwhich the openings exertwith the aid of the reduced pressure acting through them on thethread, it is proposed in a further embodiment of the device according tothe invention thatthe retaining elementformed bythe openings additionally comprise an annular bead arranged atthe discharge end of the storage roll. The resultant additional deflection of thethread meansthatthe thread is exposed to increased friction so that uncontrolled take-off of the thread from the storage roll is prevented even if there is a relatively low reduced pressure inside the storage roll.

If the thread store is intended onlyfor temporary storage of a limited thread supply, thethread advance discwhich is conventional in itself in such thread stores can be dispensed with. Instead, the storage roll can be made axially adjustable relativeto the thread feed point and the thread guide. Each newwinding is thus deposited finely and cleanly nextto the winding previously deposited on the storage roll. The advance movement of thethread store with the storage roll - or also the storage roll in thethread store- ca be controlled using means which also bring thethread store from a rest position into a working position.

The storage roll driving mechanism must be elastic in design so thatthe driving speed of the storage roll can be adapted to the tensions of the supplied and taken off thread. This can be effected, for example, by mean's of a torque motor. The storage roll can preferably be driven via a slip coupling forthis purpose.

According to a preferred embodiment of the subject of the invention, the retaining element isformed by a thread retaining ring which can be driven relativeto the storage roll instead of bythe circumferential area of the storage roll provided with openings. This rules out a special reduced pressure connection forthe storage roll, and also leadsto a reduction in the noise level. To lowerthe frictional values between and thread retaining ring and to increasethe service life of the thread retaining ring, the thread retaining ring is preferably composed of plastic.

The storage roll is preferably provided with a filling monitorwhich assumes monitoring of otherdevices depending on the parameters determined bythe application. For example, the driving mechanism of the thread store can be stopped orthe speed of a subsequent thread take-up station (for example bobbin) can be raised (see, for example, British Patent 1.573. 869).

The retaining element is preferably formed by a thread retaining ring which can be driven elastically 2 GB 2 128 213 A 2 relative to the storage roll and with whosethread retaining devicethethread engages, andwhich is provided with a rotation monitoring device, a device for determining the rotational direction of the thread retaining ring also being provided and being con- 70 nected in terms of control, together with the rotation monitoring device,to a pulse counterwhich can be switched from forwardsto backwards counting and viceversa as a function of a change in the rotational direction of thethread retaining ring. Thethread 75 retaining ring which can be driven relativelytothe storage roll remains stationary when the take-off speed coincides with the delivery speed. When the delivery speed of the thread to the storage roll exceeds the take-off speed of the thread from the storage roll, 80 the th read retaining ring revolves in the rotational direction of the storage roll whereas the thread retaining ring revolves in the opposite direction to the storage roll when the take-off speed is higherthan the delivery speed. The deg ree of revolution of the thread 85 retaining ring therefore indicates how much thread is stored on the storage roll. Forthis reason, the rotation monitoring device determines howfarthe thread retaining ring has revolved while the device for determining the rotational direction of the thread retaining ring determines whetherthe thread supply on the storage roll is increasing or decreasing. The pulse counter therefore adds or subtracts the pulses received bythe rotary monitoring device as a function of the rotational direction of the thread retaining ring so thatthe stored number of pulses relates directlyto the stored thread supply. This device for measuring the thread length stored on the storage roll can be used not only in a thread store of the above mentioned type with retaining elements which are open radially outwards but also in retaining elements having eyelets or being designed in the form of eyelets.

The pulse counter is preferably connected in terms of control to the drive of a take-off deviceto prevent certain minimum or maximum quantitiesfrom being fallen below or exceeded on the storage roll.

Thetake-off device is preferably formed by a thread take-up point arranged downstream of the storage roll in the direction of thread travel, which can bethe winding device or also a yarn-processing station, for example a knitting orweaving machine.

If thethread store isfollowed bya thread connecting deviceto rectifythread breakages orto eliminate irreularities in the thread, the thread guide arranged in the extension of the axis of the storage roll is connectedto both thethread store andthethread connecting device. In this way,thethread connecting device can be arranged very closely afterthethread fore merelywound on the storage roll. Oncethe thread connecting device hasfinished itswork, it sets the threadtake up station into operation again. With a winding device, the thread take-up speed is usually higherthan the delivery speed of athread tothe storage roll clueto the necessary drawing, so thatthe storage roll is emptied again. To preventthis emptying processfrom taking too much time, a control device connectedtothe pulse counter is advantageously provided for controlling the speed of the thread take-up station as afunction of thethread length located on the storage roll.

To prevent over-filling of thestorage roll,the pulse countercan be connected to a stopping device.

In orderto simplify further the beginning of the storage procedure, the storage roll preferably has a thread retaining devicewhich is open radiallyout wards, on its discharge end.This can be designed or mounted in variousways. According to a preferred embodimentof thesubject of the invention, it is mounted lowerably in the storage roll. In this case,the thread retaining device is advantageously loaded elastically radially inwards while there is provided in the storage roll an axially movable adjusting cone which can be caused to act on the internal end of the thread retaining device. To reduce the friction be tween adjusting cone and th read retaining device, the thread retaining device can be guided in the storage roll with security against rotation and can bear on its internal end a small wheel which is orientated in the circumferential direction of the storage roll forsup porting the thread retaining device on the adjusting cone.

A design of the subjectof the invention in which the storage roll projects beyond its discharge end in the form of a tapering truncated cone on whose surface the thread retaining device is arranged has proven extremely advantageous. By altering the orientation of the thread store relative to the thread course, by altering the distance between the thread store and the subsequentth read guide or by movement of the thread retaining device relative to the truncated cone, it is possible forthe th read retaining device to be located sometimes on a path crossing the thread cou rse and at othertimes remote from it and not to obstructthe path of the thread taken off the thread store. The arrangement of thethread retaining device in the immediate vicinity of the larger diameter of the truncated cone is particularly advantageous as, in this way, by arranging the th read store relative to the surface course in such a waythat the su rface line and thread cou rse assume an approximately parallel path, the th read can easily be taken off by a th read retaining device which projects relatively slightly beyond the store, producing a compact structure. 120 surface line of thetruncated cone. Thethread can be In a further development of the subject of the taken up by altering the thread course or by altering invention, the devicefor determining the rotational the position of the thread retaining device relativeto direction of thethread retaining ring can be formed by the thread course. The thread retaining device is a thread connecting device which is arranged between preferably mounted in a lowerably manner in the a storage roll and thread take-up point and which is 125 circumferential area of the truncated cone forthis connected in terms of control to the drive of thethread take-up station. Whilethe thread connecting device is in operation, thethread must be stationary in its working region sothatthethread take-up device is stationary. A subsequently delivered thread is there- 130 1 purpose.

If a thread retaining ring is used as retaining element, thethread retaining device is preferably part of thisthread retaining ring which can be driven relativeto the storage roll.To obtain simple driving 3 GB 2 128 213 A 3 mechanisms for storage roll and thread retaining ring, the storage roll and thread retaining ring are preferably both connected via a respective slip coupling to a common driving shaft, the storage roll as well as the thread retaining ring preferably bearing a respective hysteresis disc and a permanent magnet preferably being arranged on the common driving shaft between these two hysteresis discs.

In an advantageous embodiment of the subject of the invention, thethread retaining device is designed as a hookwhich has an open groove in the driving direction, wherein the thread retaining device can bear a ceramic insert in its groove to increase the service life.

If thethread store does not haveto operate all the timeforany reason, as isthe case, for example, with open end spinning devices, thethread store is located in such a position thatthethread course is not influenced by it in anyway- by deflection. In this case,thethread guide is preferably designed as a thread supplierwhich brings the threadfrom the predetermined thread course into a thread course crossing the path of the revolving thread retaining device, the thread guide preferably consisting of two thread guide memberswhich can be separated from each other.

If a thread breakage occurs withoutthe subsequent thread supplyto the thread store being interrupted, this causes over-filling of thethread store. If thethread store is used merely fortemporary storage of the thread and then releases the thread, which returns into a normal, i.e. undeflected, thread course, then the thread losestension temporarily. For such cases, i.e. take-up of the subsequently delivered thread length or thread length occurring duetotension drop,the mouth of a suction tube is arranged inthevicinity of thethread courseof thethread supplied to the storage roll in a further embodiment of the invention. If such a thread breakage occurs afterthethread storejor example inthethread connecting device, dueto failureof thethread connecting process, it isadvantageous if athread controllerwhich isconnected in termsof control to the device for producing and/or delivering thethread is arranged downstream of the thread connecting device in thethread courseto prevent over-f il ling of thethread store. To stopthe subsequent delivery of the thread to the thread store and also to enablethethread storeto be emptied,the thread controller is advantageously also connected in terms of control to the rotarydrive of the storage roll in further development of the invention so thatthe rotational direction of the rotary driving mechanism can be reversed.

If thethread store is needed not always but merely for specific wo rki ng phases, then it is proposed according to the invention, with a textile machine having a plurality of working stations and a maintenance device which travels pastthese working stations and can be connected to these working stations selectively, thatthe storage roll and the thread course be adapted so thatthey can be broughtto an acute angle relative to each other in such a waythat the discharge end of the storage roll is located closerto the thread course than its feed end.

Thethread store designed according to the inven- tion is extremely versatile. It can be used for all known applications, for example in weaving, knitting and hosiery machines and also in open end spinning machines, as hitherto in a stationary fashion. The preparation for work, during which the thread is brought on to the predetermined thread course, is simplified considerably as the thread can be threaded into the thread store without an open thread end having to be available. Rather, it is possible with the design of thethread store according to the invention to feed the continuous thread from the side into the thread store. This opens up completely new possibilitiesfor using the thread store and such a thread store can now be used even if it isto be supplied to the working station only temporarily for a quite specific operating phase. The thread store can thus be kept in readiness outsidethis operating phase in the vicinity of the working station or even on a maintenance device which has to serve a plurality of simiiarworking stations. Considerable savings in space and materials are thus made, particularly if the thread store is to be used on machines with a large number of similar working stations-for example, on an open end spinning machine.

The invention is described in detail belowwith referenceto drawingswhich showonlythe elements which are absolutely essential for misunderstanding the invention.

Figure 1 shows a first embodiment of a thread store designed according to the invention in section in an open end spinning machine with a thread connecting device which is shown only in section and schematically.

Figure 2 shows a frontview of the thread store shown in Figure 1, omitting the elements unnecessary forthe explanation and of the thread guide connected to the thread store.

Figure 3 shows a detail from Figure 2.

Figure 4 shows another embodiment of thethread store according to the invention, the thread store being shown in cross- section in the top half of the figure and in a side view in the bottom half.

The thread store 1 which is shown in Figures 1 and 4 can be used on basically any textile machines on which thread stores 1 with a storage roll 10 are used, for example on hosiery and knitting machines or even on weaving machines. However, as the operating conditions on an open end spinning machine are more difficuitthan on the previously mentioned machines, particularly if thethread store 1 isto be arranged on a movable maintenance device 2,the structure and functioning of thethread store 1 is explained below with referenceto an example of an open end spinning machine.

Figure 1 shows onlythe spinning device 3 indicated by a rectangle, a pairof take-off rolls 30 and a winding device 6 of such an open end spinning machine. A thread 31 produced in the spinning device 3 istaken from the spinning device 3 by means of a take-off roll pair30 and is then fed to the winding device 6 where the thread 31 is wound on to a bobbin forforming a bobbin package.

The maintenance device 2 which can travel along the open end spinning machine and can therefore serve a pluraity of spinning stations on this machine in 4 GB 2 128 213 A 4 succession is brought into thethread course between the pairof take-off rolls 30 and the thread take-up station designed as a winding device 6forthis servicing in known manner. Thewinding device 6 is provided with a driving device (notshown) which can 70 be controlled bythe maintenance device 2. In the embodiment illustrated, the maintenance device 2 also has an auxiliary pair of take-off rolls 20 which are driven by a motor 21 via a belt 22.

The maintenance device 2 has, outside the th read course 32 def ined by the pair of take-off rolls 30 of the open end spinning machine and the auxiliary pair of take-off rolls 20 of the maintenance device 2, in succession in the direction of thread travel, the above-mentioned thread store 1 as well as a thread connecting device 23 which can be designed in various ways, forexample as a knotting device.

The thread store 1 shown in Figure 1 has a base 11 with whose aid it is mounted rigidly on the mainte- nance device 2 or pivotally on a lever or rod linkage. The base 11 in turn has a hub 110 in which a driving shaft 12 is mounted via one or more bearings 111. The above-mentioned storage roll 10 which has catch slots 102 on itsfeed end 101 facing the base 11 is mounted on the shaft 12 by means of a bearing 100. Athread advance disc 13 meshes with these catch slots 102 and is rotatably mounted on the hub 110 of the base 11 by means of a bearing 130 and is therefore entrained during rotation of the storage roll 10. The thread advance disc 13 is inclined in a known mannerto the axis 122 of the storage roll 10 formed by the driving shaft 12 in orderto advance thethread in the required manner.

The base 11 has a cylindrical surface 1 12which partially surrounds the thread advance disc 13 on its circumference, butwhich, on the other hand, allows it to project by a sufficient amount beyond the end face of the surface 112 for itto exertthe necessary advancing action on thethread.

A rotary driving mechanism 120 is connected to the 105 shaft 12 and is designed as a motor according to Figure 1, but other driving mechanisms, for example gears which are driven by other driven elements, can also be used. This rotary driving mechanism 120 is borne bythe base 11 of thethread store 1. Atitsfree 110 end, the driving shaft 12 bears an end plate 121 which revolves together with the shaft 120 at the same speed.

A retaining element designed as a thread retaining ring 14 is mounted rotatably on the shaft 12 by means 115 of a bearing 140 between the end plate 121 and the storage roll 10 according to Figure 1. The thread retaining ring 14 covers both the discharge end 103 of the storage roll 10 and the external circumference of the end plate 121 with a short circumferential area 142 120 in orderto avoid the risk of the thread 31 jamming between thethread retaining ring 14 and the storage roll 10 on the one hand and the end plate 121 on the otherhand.

Figures 2 and 3 show a portion of the thread 125 retaining ring 14. As can be seen, the thread retaining ring 14 has onits periphery several thread retaining devices 141, but a single one of these thread retaining devices 141 is sufficient in certain circumstances. The thread retaining device 141 orthe thread retaining devices 141 is or are designed open radially outwards so thatthe thread 31 can be brought into the contact area of the thread retaining device 141 from the outside. According to Figures 2 and 3, the thread retaining device 141 has the form of a hook which has an open groove 144 in the driving direction 145 (see Figure 2) of thethread retaining ring"14. For protection againstwear, this groove 144 is provided with a ceramic insert 146 according to Figure 3. The bearing 100 on the storage roll 10 is arranged ata distance from its discharge end 103 so thatthe storage roll 10 surrounds a space 15with a radial wall 104together with thethread retaining ring 14. A permanent magnet 150 is arranged on the driving shaft 12 in this space 15 at a distance from the radial wall 104 and alsofrom the thread retaining ring 14. The storage roll 10 bears on the side of its radial wall 104facing the permanent magnet 150 a hysteresis disc 105, while the thread retaining ring 14 bears on its sidefacing the perma- nent magnet 150 a hysteresis disc 143. The two slip couplings designed as hysteresis couplings aretherefore driven bythe shaft 12 via a single permanent magnet 150.

Athread guide 4 consisting of two thread guide members 40 and 41 which can be moved relative to each other is located in prolongation of the axis 122 of the thread store 1 formed bythe driving shaft 12. According to Figure 1, thethread guide member40 is held stationarily bythe maintenance device 2 while thethread guide member41 is held movably bythe maintenance device 2. According to Figure 2,thetwo thread guide members40 and 41 arefork-shaped in design, the thread guide member41 being mounted pivotallyon the pivot axis 42. Thethread guide member41 can be moved from a readiness position 410 into the closed position shown by a pivoting drive mechanism (not shown), so that it grips the thread 31 following the thread course 32 and takes it into the position shown in Figure 2 in which the thread 31 is enclosed between the thread guide members 40 and 41 and guided.

The storage roll 10 is provided with a rotation monitoring devicewhich comprises a scanner50 scanning thethread retaining ring 14.The scanner is connected to a pulse counter5to which thethread connecting device 23 is also connected in terms of control. The pulse counter 5 is in turn connected to the motor 21 of the auxiliary pair of take-off rolls 20 in terms of control via a control device 51.

The mouth 240 of a movable suction tube 24 is arranged in the vicinity of thethread course 33 between thetake-off roll pair 30 and the thread store 1, while the mouth of a suction tube 26 is arranged in the vicinity of the thread course downstream of the auxiliary pair of take-off rolls 20.

Between thethread connecting device 23 and the auxiliary pair of take-off rolls 20there is located a thread controller25 which is connected via a control device 250to the rotary driving mechanism 120 of the thread store 1 and to a delivery device for supplying a fibre sliverwhich is to be opened into individual fibres to the spinning device 3. Athread deflecting device 27 is also located between thethread controller 25 and the winding device 6.

The device described constructionally above oper- ates as follows:

During the normal undisturbed spinning process, thethread 31 produced in the spinning device 3 is taken off the spinning device by the pair of take-off rolls 30 and is fed to the winding device 6. If a thread breakage occurs, the maintenance device 2 is brought in known mannerto the respective spinning station where it removes the thread breakage. The partially spunthread31 is then severed while the winding device 6 is stationary, the thread portion extending to the winding device 6 being supplied via the thread deflecting device 27 to the suction tube 24 which is located in, the position 241 and thus keeps this thread portion tensioned. The other thread portion which is continuously delivered through the spinning device 3 is inserted Into the auxiliary pair of take-off rolls 20 and fed to the suction tube 26 and there sucked continuously.

Thethreadstorel islocatedwithitsaxisl22atan acute angle otto the thread course 32, the discharge end 103being located closerto the thread course 32. The rotary driving mechanism 120ofthethread store 1 drives the storage roll 10 and the thread retaining ring 14 which follow this driving movement without obstruction, via the shaft 12, the permanent magnet 150 and the hysteresis discs 105 and 143. The rotational speed of driving shaft 12, storage roll 10 and thread retaining ring 14 which initially revolve synchronously is selected in such a way thatthe circumferential speed of the storage roll 10 is higher than the speed atwhich thethread 31 istakenoffthe spinning device 3 by the pair of take- off rolls 30.

The thread guide member 41 is nowtaken from its readiness position 410 into the illustrated closed position in which the thread portion extending to the auxiliary pair of take-off rolls 20 is enclosed between the thread guide members 40 and 41. This thread portion passes into the path of the revolving thread retaining device 141 which is prevented f rom revolv- ing any more by this thread portion which is held with tension by the auxiliary pair of take-off rol Is 20 revolving at the same speed as the pair of take-off rolls 30. However, the storage roll 10 revolves at an unreduced speed. The thread portion is also initially taken off by the auxiliary pair of take-off rolls 20 and 110 discha rged th rough the suction tu be 26 following this auxiliary pair of take-off rolls 20.

The other th read portion which extends f rom the winding device 6 to the mouth 240 of the suction tu be 24 is guided in such a way that it does not enter the thread store 1. The two thread portions to be connected are guided parallel to each other

in the mannerjust described by the thread deflecting device 27 and the suction tube 24 or by the thread guide 4 and the auxiliary pair of take-off rolls 20, so thatthey can be taken up reliably bythethread connecting device 23 forthread connec tion.

Providing the thread connecting device 23 has not yet commenced its work, the thread retaining ring 14 125 of thethread store 1 acts as a thread compensating element. In fact, if thethread tension temporarily slackens somewhat, the thread retaining ring 14twists in the driving direction 145 and causes a certain looping of the storage roll 10 which is removed again 130 GB 2 128 213 A 5 when the thread tension increases again, for example on completion ofthread connection.

Thethread connecting device 23then begins its work, sothatthethread portionsto be connectedto each other haveto be stopped. The thread connecting device 23 stops the motor 21 via the control device 5 so thatthe auxilia ry pair of take-off rolls 20 is also stopped.

The thread portion still produced by the spinning device 3 and su bsequently delivered by the pair of take off rolls 30 therefore relaxes so that the th read retaining device 141 which had already gripped this thread portion now also begins to revolve. The subsequently delivered thread length therefore reaches the storage roll 10 and is deposited there so that the th read advance disc 13 moves the earlier windings in a known manner from the feed end 101 of the storage rol 110 sufficiently far towards its discharge end 103 for the new windings always to be deposited between the existing windings and the thread advance disc 13.

Atthe beginning of the storage operation, the storage roll 10 is slowly reduced to the thread delivery speed which is predetermined bythe rotational speed of the pair of take-off rolls 30. The thread retaining ring 14 with thethread retaining device 141 also follows this change of speed as only fluctuations on the discharge side of the thread store 1 lead to relative movements between the storage roll 10 and thread retaining ring 14. However, as no thread has been taken off the thread store 1 during thread connection and as the thread guide 4 is located in an extension of the axis 122of thethread store 1 so that no alterations intension occur from the thread discharge side of the thread store 1, the thread retaining ring 14andstorage roll 10 revolve in synchronisation. As the location of thread supply to the thread store 1 isafixedpoint,the revolutions of the thread retaining ring 14representa gauge of the thread supply located on the storage roll 10. The revolutions of the thread retaining ring 14 can therefo're be used for measuring the quantity of thread stored on the storage roll 10. The storage roll 10is therefore provided with the rotation monitoring device whose scanner 50 essentially contains a light source and a photocell or is designed as an induction scanner. The rotation monitoring device therefore determines the passages of thethread retaining device or devices 141 photoelectrically or inductively while the thread connecting device 23 is in operation.

While thethread 31 is stored on the thread store 1, it is possible for an excess of thread, which occurs temporarily atthe beginning of operation or atthe end of operation of the thread connecting device 23, to be stored bythe thread store 1, in which case, the thread retaining ring 14temporarily advances in the driving direction 145 relative to the storage roll 10, which path is also determined by the rotation monitoring device and recorded in the form of pulses by the pulse counter5.

As thetwo thread portions extending to the thread store 1 and to the winding device 6 are being connected bythe thread connecting device 23, the thread ends extending to the suction tube 24 and to the suction tube 26 are severed and sucked away.

Once thethread connecting device 23 has corn- 6 pieted its work, it transmits a corresponding control command via the control device 51 to the winding device 6 which now begins its winding work again. Dueto the winding tension, the thread reserve collected onthethread store 1 istaken off.The pulse counter5 issetto backwards counting as a resultof the control pulse emitted to the control device 51 by the thread connecting device 23. The thread connecting device therefore acts as a device for determining the rotational direction of the thread retaining ring 14, asthe thread retaining ring 14 is twisted againstthe driving direction 145 of the storage roll 10 bythetaken offthread 31 as the thread 31 is removed from the storage roll 10 of the thread retaining ring 14. By comparing the pulses emitted during reverse rotation 80 of the thread retaining ring 14 with the number of pulses emitted during the previous rotation in the driving direction 145, it is possible to determined whetherthe stored thread reserve has been used up or not. Once the pulse counter has reached the value zero 85 again, it swithches overso that itwill countforwards again during the next storage process.

Such a device for measuring the state of fullness of the storage roll 10 by means of a pulse counter hasthe advantagethat it operates independently of the thread 90 speed, the thread thickness, the speeds on the thread store and the dimensions of thethread store. This applies regardless of the duration of storage. The degree of filling of thethread store 1 is determined only bythe number of rotations of thethread retaining 95 ring 14 in thewinding direction (= driving direction 145).

To prevent the thread reservefrom being taken off the storage roll 10 in an uncontrolled fashion, the thread31 must always be kept undertension. This is effected by the thread retaining ring 14 driven via the permanent magnet 150 and the hysteresis disc 143. It is therefore only possible to remove the thread 31 from the storage roll 10 when tension differences occur in the thread 31 due to differences in the delivery 105 rate to the thread store 1, which is predetermined by the rotational speed of the pair of take-off rolls 30, and the take-off speed from the thread store 1, which is initially determined by the rotational speed of the auxiliary pair of take-off rolls 20 and subsequently by 110 the winding speed of the winding device 6 or by the absence of a take-off when the thread connecting device 23 is in operation. However, the peaks of tension occurring are absorbed immediately by changes in the revolution of thethread retaining ring 14 duetothe elastically operating coupling permanent magnet 150 and hysteresis disc 143. The thread retaining ring 14with itsthread retaining device 141 therefore acts as a retaining elementwhich only permitsthe quantityof thread corresponding to the actual excess speed of the predetermined take-off speed relative to the delivery speed to leavethe storage roll 10.

After emptying the thread store 1, the maintenance device 2 can leave the spinning station and travel to anotherspinning station to resume its work.

The device described above with referenceto a preferred embodiment can be modified in numerous ways depending on its application.

For example, the rotary driving mechanism 120 GB 2 128 213 A 6 need not have its own driving motor but the shaft 12 can be driven via suitable gearing byany rotating part of the maintenance device 2, if provided, which is suitable for this purpose or by the machine. Instead of a common permanent magnet 150for driving the storage roll 10 and the thread retaining ring 14, it is also possibleto provide two separate permanent magnets which are spatially separated from each other so that the driving couplings designed as slip couplings are quite independentfrom each otherfor the storage roll 10 and the thread retaining ring 14. The necessarytorques and outputs of the hysteresis couplings (hysteresis disc 143 and permanent magnet 150 as well as hysteresis disc 104 and permanent magnet 150) should be selected according to the parameters and adjusted if necessary by altering the distance between hysteresis disc 143 or 104 and permanent magnet 150. Separate permanent magnets which are adjustable on the driving shaft 12 for the two hysteresis discs 143 and 104 are particulary advantageous for such a case. It is also possible to provide eddy current orfluid couplings instead of hysteresis couplings, in which case it is also conceivable to provide separate driving mechanismsjor exampletorque motorsjorthe storage roll 10 and the thread retaining ring 14.

The thread retaining ring 14 can also be driven via a friction coupling bythe storage roll 10, in which case a felt bearing etc., can be used asfriction coupling. Driving of thethread retaining ring 14 independently of thestorage roll 10, however, hasthe advantagethat drops in thread tension occurring on the side downstream of thethread store 1, based on the thread travel, can also be compensated bythethread retaining ring 14.

The driving mechanism shown in Figure 1, however, is particularly advantageous as it is extremely compact, requires no electric lines extending inside thethread store 1 and can even compensate drops in thread tension occurring downstream of the thread store 1.

Thethread retaining ring 14can also be designed in differentways and can be producedfrom various materials. It is advantageous but not necessary in all cases forthe thread catching device 141 to be designed asa hookas particularly quicktake-up ofthe thread 31 bythethread retaining device 141 crossing thethread course 34 is ensured in thisway. If a thread retaining device 141 designed as a hook is provided, its groove 144 is open in the rotational direction 145 determined by the rotational direction of the rotary driving mechanism 120, as thethread 31 is thus held particularly securelyand guided both during winding onto the thread store 1 and during unwinding from the thread store 1.

Thethread retaining ring 14can be producedfrom metal and can be protected by ceramic inserts 146in the region ofthe grooves 144of thethread retaining device 141. Itis also possibleto provide, instead of ceramic inserts 146,small wheelswhoseaxis is orientated in such away thatthe wheels can rotate in the direction of thread travel, thus reducing the friction. However, athread retaining ring 14composed of plasticis particularly advantageous asthe thread retaining ring 14should havea minimal 7 GB 2 128 213 A 7 momentof inertia duetothe needto be ableto accelerate the thread retaining ring 14quicklyatthe beginning of storage.To increasethe resistanceto wearof a thread retaining ring 14composed of plastic, thethread retaining ring 14can havecoated,for example chromium-plated, thread retaining devices 141 which notonly increase the service life but also reduce the sliding values betweenthread31 and thread retaining ring 14.

Thethread guide4which can be opened and closed 75 can also be designed in variousways. Forthread stores 1 which areto be used on hosiery and knitting oreven weaving machines, in particular, it may be sufficieritto design thethread guide4 having aform of eyeletwith an arc-shaped portion which is held elastically in contactwith the arc-shaped remainder of thethread guide4 and can befolded open manuailyor automatically againstthe action of a spring. The illustrated design of a divisible thread guide4with two thread guide members 40 and 41 which can be removedfrom each other is particularly suitable as thread supplierwith which thethread 31 can be broughtinto the position in prolongation of the axis 122 of the thread store 1 between the two thread guide members40and41 by a pivoting or also pushing movement of the movable thread guide member 41.

However, it is also possible, by suitable arrangement ofthethread store 1 relative to the thread course 32, to ensure that the thread 31 also crosses the path of the thread retaining device 141 withoutthe aid of a thread 95 supplier and enters the correspondingly controlled thread guide 4, with the aid of the thread retaining device141 if necessary. With the thread connecting device 23 which is arranged downstream of the thread storel in the direction of thread travel, this thread guide 4can also be arranged in such a waythat it is connected not only to the thread store 1 butatthe same time to the thread connecting device 23, and presents the thread 31 to this thread connecting device 23 in the manner required for subsequent 105 operation of the thread connecting device 23.

The device for determining the direction of rotation of the thread can also be designed in various ways. In the design described above it is formed by the thread connecting device 23, as the thread store 1 increases 110 or diminishes the stored thread supply as a function of its operation. However, it is also possible to provide the thread retaining ring 14 orthe storage roll 1 Owith a pair of scanners which determines the direction of rotation of the thread in a manner known per se. Such 115 a scanner pair also permits precise determination of the moment atwhich the thread changes its rotational direction. The winding device 6 can be connected very gently so that the rotational direction of the thread also changes after a delay relative to the working end of a thread connecting device 23 without errors being ableto occur in the value stored by the pulse counter 5 Monitoring of the fullness can also be dispensed with, depending on the application of the thread store 1. In this case, it is sufficient to connect from the thread connecting device 23 a timing member which measures the duration of operation of the thread connecting device 23 and emits a signal that the thread store 1 is empty as a function of this period. Forthis purpose, the timing member can be adjusted beforehand in various ways so that different times forth read connection, different thread delivery and takeoff speeds, different initial tensions can be taken into consideration in this time with sufficient reliability etc.

If a filling monitor is provided, then it can be designed in various ways. As shown in the example in Figure 1, a pulse counter 50 is provided which determines by forwards or backwards counting whetherthe storage roll 10 isfull or empty. As an alternative, the thread advance disc 13 can be elastically charged in such away that it actuates a switch when thread windings are applied and releases this switch by the action of the charging force during release by thread windings -i.e. when the storage roll 10 is empty. Or, one of thecatch slots is extended towards the discharge end of the storage roll 10 and takes up an arm which is normally pressed outwards beyond the peripheral surface of the storage roll 10 by the action of a spring. However, if a thread supply is stored on the storage roll 10, the thread windings coverthis elastically mounted arm and press it radially inwards againstthe action of the spring. This elastically mounted arm is part of a switch or actuates it,thus providing a monitor of fullness, as in the example described with referenceto the thread advance disc 13.

In particular, if the thread store 1 can be connected to several working stations in succession,for example when mounted on a pivoting arm with whose aid the thread store can be connected to at leasttwo adjacent working stations or even when mounted on a maintenance device 2 travelling past a plurality of working stations, it is advantageous if the thread store 1 is quickly emptied again and can therefore very quickly be taken awayfrom this working station again. Forthis purpose, the control device 51 shown in Figure 1 is not only capable of switching the motor 21 and the winding device 6 on and off but is also designed as a speed control. This speed control which, as shown, communicates with the pulse counter 5 (or a fullness monitor of a different design as well as thethread connecting device 23) receives a signal from the thread connecting device 23 when it commences operation, to stop the auxiliary pair of take-off rolls 20 and the winding device 6. The rotation monitoring device 50 now records the revolution of thethread retaining ring 14. Once thethread connecting operation is completed, this is signalled bythe thread connecting device 23 to the control device 51 which now imparts to the winding device the command to take off the thread 31 from the storage roll 10 at a higher speed. Just before the storage roll 10 is completely emptied, the pulse counter 5 transmits the corresponding signal to the control device 51 which now reduces the speed of the winding device 6 which has temporarily been increased for example, by 30%, to the normal production speed. This takes place in a stepped fashion or continuously in such a way thatthe stored thread reserve is used up on reaching the normal winding speed.

For example, the control device 51 has a digital/ analog converterwhich converts the numberstored bythe pulse counter 5 into an anlog value. This analog value controls the speed of the winding device, and by suitable design of the control device 51 it is possible to 8 prevent a predetemined peak value from ever being exceeded. This peak value is a set value which therefore characterises the highest winding speed.

The actual value which is to be compared with it is produced from the sum of the value characterising the 70 normal winding speed and the analog value derived from the pusle counter 5. If this sum (actual value) is lowerthan the setvalue, it determines the speed of the winding device 6, whereas the set values determines the speed of the winding device 6 if this actual value exceeds the setvalue. Asmooth transition from the speed of thewinding device 6to the normal winding speed can be achieved inthis way.

The suction tube 24 holdsthe thread portion extending to the winding device 6 during thread 80 connection. It is also possible forthe suction tube 24to collect the thread portion forthis purposefrom the winding device 6 or a transfer device which has taken thethread from the winding device 6. During the thread connecting operation, however, or at least at 85 the beginning of this operation when thethread connecting device 23 takes up the thread portion, the mouth 240 of the suction tube 24 assumes the position 241 shown in a broken line, butthen travels into the position shown with a solid line in figure 1. In this 90 position, the suction tube 24takes up the thread 31 which has been released from the thread store 1 during emptying thereof and nowtemporarily assumes the thread course 35. This excess thread is also used up during winding up virtually without any 95 significarittension variations due to the normal winding tension, so that the quality of the windings on the bobbin is not impaired.

If the thread connecting process has failed, this is determined bythe thread controller 25. The thread 100 controller 25 immediately stops the supply of thread 31 to the thread store 1 and, forthis purpose, is connected in terms of control via the control device 250 to the device for producing (spinning device 3) or for delivering the thread 31 (take-off device fortaking 105 off the thread from a bobbin, for example in a yarn-processing oryarn-treating machine). The sub sequent delivery of the thread 31 tothethread store 1 is therefore stopped. It is now necessary to free the storageroll 1 from its thread 31 to avoid excessive 110 stored quantities. This can obviously be effected manually. In the embodiment shown, the thread controller25 is instead connected via the control device 250 additionally to the rotarydrive mechanism 120 of thethread store 1. If a thread breakage is 115 recorded downstream of thethread connecting device 23, the subsequent delivery of the thread 31 to the thread store 1 is stopped and atthe sametime the rotational direction of the storage roll 10 is reversed by reversing the rotational direction of the rotary driving 120 mechanism 120, so thatthe suction tube 124can take-off and discharge the thread 31 stored on the storage roll 10 and generally extending tothethread connecting device 23.

Thethread store 1 can also be emptied in a different way. For example, the thread guide4 has a pairof rollers (notshrwn) with a removable pressure roller which takesthethread from thethread store 1 during the occurence of a thread breakage and further supplies itto a suction device (not shown).

GB 2 128 213 A 8 If a thread breakage occurs, a command is given afteremptying thethread store 1 so thatthe maintenance device 2 can repeatthe unsuccessful initial spinning process.

As shown and described, the thread store 1 is located in a position which is inclined at an acute angle (xto the thread course 32 as supply of the thread 31 to the thread store 1 is simplest in this case. However, different arrangements of the thread store l relativeto the thread course 32 are also possible if suitable stationary or moving thread guides ensure thatthe thread 31 can be brought into a path crossing the thread retaining device 141.

With a stationary arrangement of thethread store 1, i.e. if thethread store invariably remains in the operating position during operation of the device to which it is connected, for example the thread feed position of a knitting machine, and thus invariably bears a certain quantity of stored thread, a thread collector is not necessary as the thread 31 isthen firstly applied to the thread store 1 manually and suitable measu res ensu re that the stored quantity of thread does notfall belowcertain minimum values norexceed certain maximum values.

The pulse counter 5 can control various processes, depending in which machine thethread store 1 is used. For example, on reaching a certain value, it can stop a device which is connected to it, for examplethe delivery device of a winding device 3. This is desirable, for example, if several consecutive attempts to connect the thread 31 using the thread connecting device 23 have failed, as the thread store 1 would otherwise be overfilled. Similarly, it may be necessary to stop a knitting machine once the pulse counter 5 has reached a certain value asthis indicates a fault in the thread path.

However,the pulse counter 5 can also be connected in terms of control to the driving mechanism of a take-off device. This is the case in the example described above in which the take off device is formed bythe winding device 6. However, it is also conceivable thatthis take-off device isformed by a knitting machine orthe like or bythe thread store 1 itself if it takes off the thread 31 from a supply bobbin and is not supplied by means of a pair of take-off rolls 30. In this case, the driving device 120 is stopped so thatthe thread store 1 can no longertake up thread.

An embodiment of a thread store 7 which can be designed both with and without a thread retaining device or catcher 8 is described belowwith reference to Figure 4. The reference numerals used in Figure 1 are also used in the following description forthe elements which arethe same as the corresponding elements in Figure 1.

Thethread store 7 according to Figure 4 is shown in section in the top half of thefigure but in an elevation in the bottom half of this figure.

Like the thread store 1 shown in Figure 1, the thread store 7 also has a base 11 by means of which the thread store 7 is mounted in a suitable manner, for example in a maintenance device 2 so as to remain in the example of an open end spinning machine. In the hub 110 of the base 11 there is again mounted by means of a bearing 111 a shaft 12 with which the storage roll 70 is rotationally engaged atone end. The 1 f 9 other end of the driving shaft 12 is connected to a rotary driving mechanism 120 (see Figure 1, for example torque motor or other motor with an interposed slip coupling), so that the storage roll 70 is driven as a function of the resistance opposed by the thread 31.

In the example shown in Figure 4, the storage roll 70 has on itsfeed end 101 facing the base 11 slots 102 which, unlike the embodiment in Figure 1, are sealed on the interior of the storage roll by an inserted ring 71. The thread advance disc 13 engaging in these slots 102, also unlike the embodiment in Figure 1, is mounted on its exterior in the surface 112 of the base by means of a bearing 113.

The storage roll 70 has an annular bead 72 on its discharge end 103 which passes into a tapering truncated cone 73. Overthe entire storage length 74, Le,between thefeed end 101 and the discharge end 103, the storage roll 70 has over its peripheral surface a plurality of uniformly distributed openings 75 which are designed as longitudinal slots in the embodiment shown. Also, a corresponding number of cylindrical bores which are distributed overthe storage length 74 in such a way thatthe stored thread 31 is always located in the region of influence of at least one such opening 75, can be used, these openings 75 advan tageously being located in lineswhich loop the storage roll 70 in the manner of screwthreads.

Atubular portion 76 into which the suction nozzle 77 of a suction line connected to a vacuum source (not shown) opens is connected to the base 11 on the side turned awayfrom the storage roll 70. The portion 76 is connected via bores 760 in the base 11 to the interior 78 of the storage roll 70.

If the thread store 7 is in operation, there is 100 connected to the suction nozzle 77 a vacuum which actsthrough the bores 760 and the openings 75 on the exterior of the storage rolls 70 as the interior of the thread store is otherwise sealed to the exterior (see ring 71). If a thread 31 is placed on the storage length 105 74 of the storage roll 70 which is driven by a rotary driving mechanism 120 permitting slippage, the vacuum sucks the thread 31 and holds it securely. If the thread 31 is to be removed from this storage roll 70 at a later moment, these openings 75 and the vacuum 110 acting on the thread 31 act as retaining eiementforthe thread 31. To increase this retaining effect of the thread 31 on the storage roll 70, the storage length 74 of the storage roll 70 is limited on its discharge side 103 by the above-mentioned annular bead 72 as an 115 additional measure in the embodiment illustrated, as this annular bead 72 provides an additional deflection forthethread31 and therefore additional frictional surfaces for the thread to be taken off. Incomparison with a design of such thread store 7 whose retaining 120 element is formed by openings 75 subjected to suction, but having no such annular bead 72, the retaining effect is even better.

Athread retaining device 8 is also provided in this case to enable the thread 31 to be supplied automati- 125 cally in such an arrangement of the thread store 7 of the storage roll 70. In contrastto the design according to Figure 1, in which the thread collector 141 can perform a movement relative to the storage roll 10, the thread retaining device 8 is always entrained by the 130 GB 2 128 213 A 9 storage roll 70 during its rotational movement. To enablethethread retaining device 8to operate only during its collecting work but nototherwiseto obstructthread take-off from thethread store 7, the thread store 7 is designed and mounted in the storage roll 70 in such a waythat it can be lowered in the storage roll 70 and no longer projects beyond the surface of the storage roll 70.

The thread retaining device 8 must also be open outwards, forwhich purpose thread collectors designed as hooks can also be used, as also shown in the embodiment in Figures 2 and 3.

According to a structurally simple and therefore preferred embodimentwhich is described with refer- ence to the embodiment in Figure 4,there is connected on the side of the annular bead 72 turned away from the storage length 74 of the storage roll 70 a truncated cone 73 whose largest diameter corresponds to the diameter of the annular bead 72 and which tapers towards its free end. A bush 80fortaking up the thread retaining device 8 is mounted in this truncated cone 73 in the vicinity of the annular bead 72 and comprises a retaining pin 81. The retaining pin 81 bears inside the bush 80 a plate 82 on whose side facing the exterior of the truncated cone 73 there rests a compression spring 83 which, in turn, rests on the external base 84 of the bush 80. Another base 85 of the bush80 againstwhich the plate 82 rests during release of the internal end of the catching pin 81 is provided on the side facing the interior 78 of the thread store 7 to limitthe lifting movement.

In the storage roll 70there is guided an axially movable adjusting cone 9 bearing a support disc 90 which serves on the one hand to supportthe storage roll 70, and to which there are connected, on the other hand, several driving bolts 91 which are uniformly distributed over its periphery and are guided with security against rotation in the base 11 by correspondingly distributed bores 114. The driving bolts 91 are connected attheir end turned awayf rom the support disc 90 to a suitable lifting driving mechanism (not shown), for example a lifting magnet, a pneumatically or hydraulically charged lifting piston etc.

On the side of the support disc 90 facing the truncated cone 73, there is located the actual cone 92 which can be caused to act on the retaining pin 81 by moving along the driving shaft 12 of the thread store 7 and releases the retaining pin 81 again. As the storage roll 70 and the driving shaft 12 revolve whereasthe adjusting cone 9 does not rotate, suitable bearings can obviously be provided between adjusting cone 9 and storage roll 70 on the one hand and between adjusting cone 9 and driving shaft 12 on the other hand.

If the path of the retaining pin 81 and the thread course 32 cross as the result of suitable movement of the thread guide 4 (Figure 1) or of the thread store, the cone 92 is broughtto rest againstthe internal end of the retaining pin 81 or, if several retaining pins 81 are provided, on the inner ends thereof by actuating the lifting driving mechanism (not shown) via the driving bolt 91. As a result, the retaining pin or pins 81 are pushed out of the surface of the truncated cone 73 of the storage roll 70 againstthe action of the compression springs 83 allocated to them. The thread 31 is grasped by the retaining pin81 orone of them during rotation of the storage roll 70 and the winding of the thread 31 on the thread store 7 effected in this way.

Before the take- off of the thread 31 from the thread store 7 is interrupted, the thread 31 iswoundonthe storage roll 70 as quickly as it is taken off sothat a single winding initially remains.

To ensure that this one winding is not formed before thethread31 is stopped in the region downstream of the thread store 7, the lifting driving mechanism of the adjusting cone 9 is preferably also actuated from the device causing stoppage of thread take-off in the region of the thread connecting device 23. Thus, it is proposed when using a thread store 7 instead of the thread store 1 in an open end spinning device according to Figure 1 thatthe thread connecting 80 device 23 control the lifting magnets forthe driving bolts 91. When the lifting magnetfalls on completion of the work of theth read connecting device 23, the cone 92 is retracted from the collecting pin 81 which now releases the thread 31. However, the thread 31 is retained on the surface of the storage roll 70 dueto the vacuum acting in the openings 75 until the thread is taken off the storage roll 70 exactly as required by exertion of the increased tension exerted bythe winding device 6 on the thread 31.

In a simple design of the device it is sufficientto keep the wearof the retaining pin 81 in acceptable limits by suitable choice of material and bythe choice of the shape of the internal end of the retaining pin 81.

However, to increase the service life, it mayalso be proposed thatthe retaining pin 81 be secured against rotationJor example by non-round shape of the retaining pin 81 itself or of its plate 82 and correspond ing guidancethrough the bush 80 or its bases 84and 85, and that it bearon its internal end a small wheel 86 100 which is orientated in the direction of revolution of the storage roll 70 and rolls on the cone 90 when the cone comes into contact with the small wheel 86.

The retaining pin 81 can obviously also be driven radially in a different mannerthan shown. For example,the internal end of the retaining pin 81 has a driving footwhich is guided in a radial wall (not shown) of the storage roll 2 in one of two parallel guide tracks, and the driving foot of the retaining pin 81 can be passedfrom one guidetrackto another by an adjustable distributing guide. The distributing guide can be actuated mechanically or electromagnetically.

Thetwo guidetracks are arranged concentrically to each otherand merely have distributing guides with whose aidthe driving foot can passfrorn the internal guidetrack into the external guidetrack. If the driving foot is located in the internal guidetrack, the retaining pin 81 is lowered inthe peripheral wall of thetruncated cone 73whereas if the driving foot is located in the external track,the collecting pin projects beyond the peripheral wall of thetruncated cone.

In a design of a thread store 7 according to Figure 4, it is possible in principleto arrange the thread retaining device 8 also on the cylindrical end of the storage length 74 of the storage roll 70 or on the periphery of the annular bead 72 so that the truncated cone73 is not necessary. However, it has been found thatthe arrangement of the collecting pin 81 in the truncated cone 73, particularly in the vicinity of its greatest diameter, is particularly advantageous, as the 130 GB 2 128 213 A 10 thread 31 can becollected bya reiativelyshort retaining pin 81 andtherefore bya relativelyshort lift ofthe adjusting cone 9 if thethread store7 is arranged relative to the thread course32 in such a waythatthe surface line of thetruncated cone 73 is located approximately parallel tothethreaded course and in the immediate vicinity thereof, even ifthethread guide4 is notclesigned as a thread supplier.

Instead of a lowerable retaining pin 81 in the truncated cone 73, it is also possible forthis truncated cone 73 to have a non-controllable thread collector on its surface and forthis thread collectorto be brought into the region of the thread course 32 by shortening the axial distance between thread store 7 and thread guide 4. Thethread store 7, or possibly only the storage roll 70, is also adjusted relative to a feed position (take-off roll pair30). It is therefore also possible to continue this movement after collection of the thread 31 so thatthe thread 31 can be deposited winding by winding nextto each other on the storage roll 70 withoutthe aid of a thread advance disc 13, so that thethread advance disc 13 can also be dispensed with.

With a device according to Figure 4, it is also simple to determine whetherthe storage roll 70 still carries thread windings or is empty by means of a fullness monitor comprising a pulse counter. When winding the thread 31, the stored quantity of thread can be measured during the passage of the retaining pin 81, in the same manner as described with referenceto Figure 1. When taking the thread off the storage roll 70, the thread revolutions on the annular bead 72 can be counted, which oppose those of the annular bead, which is permitted by suitable choice of material for storage roll 70 and thread 31 with differing reflex properties.

If the delivery of thethread 31 to the thread store 1 or 7 is interrupted during the occurrence of a thread breakage, for example on knitting machines, the suction tube 24 can also be dispensed with, while the suction tube 26 is not needed on knitting machines anyway.

The auxiliary devices connected to the thread store 1 and 7 are therefore provided only when using the thread store 1 and 7 in specific machines ordevices, whereas they can be dispensed with in other machines or devices. Thus, for example, the thread controller 25 is not necessary in all applications since, for example, the fullness monitor can interruptthe subsequent delivery of the thread 31 tothethread store 1 or7inthecaseof athread breakage downstream of thethread store 1 or7. Nevertheless, the thread store 1 or 7 also has the advantage that the continuous or uninterrupted th read 31 can be applied to the thread store 1 or 7 at any time and ca n be stored there, but on the other hand the thread 31 canalsobe taken down again from the thread store 1 or 7 without interruption of itsthread path. Thethread store 1 or7 therefore opens up numerous applications and is not restricted to the described applications on an open and spinning station, on a knitting, a hosiery or even a weaving machine, but can be used anywhere in the textile industry where the compensation of temporary variations in thread tension is necessary and where it is necessary to take up in a regularfashion excess i t i 11 GB 2 128 213 A 11 thread material which istemporarily being formed in such awaythatitcan besupplied directlyto a thread take-up station as the temporarily stored quantity of thread is used up. Ath read take-up station should be interpreted here as a yarn-processing station, for example a knitting, hosiery orweaving station, but also a thread collecting stationjor example, the winding device 6.

Other modifications of the subject of the invention by exchange of elements or by equivalents and 75 combinations hereof fall within the scope of the present invention.

Claims (35)

1. A thread store with a rotary drive mechanism and a storage roll which can be driven by this rotary mechanism and to whose feed end the thread can be fed approximately tangentially from a feed point and from whose discharge end the thread can be taken off againstthe action of a retaining elementthrough a thread guide arranged in prolongation of its axis, characterised in thatthe storage roll has a retaining elementwhich is open radially outwards and can be driven and in thatthethread guide can be opened and closed.

2. A thread store according to Claim 1, characterised in thatthe retaining element is formed by the circumferential area of the storage roll provided with a plurality of openings, which openings open into the interior of the storage roll which, in turn, is connected to a reduced pressure source.

3. Ath read store according to Claim 2, characte rised in thatthe openings are designed as slots which extend approximately over the entire storage length of the storage roll.

4. Athread store according to Claim 2 or 3, 100 characterised in that the retaining element comprises an annular bead arranged atthe discharge end of the storage roll.

5. Ath read store according to any of Claims 1 to 4, characterised in thatthe storage roll is axially adjust- 105 able relative to the thread feed point and the thread guide.

6. Ath read store according to any of Claims 1 to 5, characterised in thatthe storage roll can be driven via a slip coupling.

7. Athread store according to Claim 1 or6, characterised in that the retaining element is formed by a thread retaining ring which can be driven relative to the storage roll.

8. A thread store according to Claim 7, characte- 115 rised in that the thread retaining ring is composed of plastic.

9. A thread store according to any of Claims 1 to 8, characterised in thatthe storage roll is provided with a filling monitor.

10. A thread store with a rotary drive mechanism as well as a storage roll which can be driven bythis rotary drive mechanism, to whose feed end the thread can be fed substantially tangentially from a feed point and from whose discharge end the thread can be taken off against the action of a retaining element through a thread guide arranged in prolongation of its axis, in particular according to Claim 1, characterised in that theyetaining element is formed by a thread retaining ring which can be driven elastically relative to the storage roll with whose thread retaining device the thread engages and which is provided with a rotation monitoring device, and in thatthere is provided a devicefor determining the rotational direction of the thread retaining ring which, together with the rotation monitoring device, is connected to a pulse counter which can be switched overfrom forwardsto backwards counting and vice versa as afunction of a change in the rotational direction of thethread retaining ring.

11. A thread store according to Claim 10, characterisedon thatthe pulse counter is connected in terms of control to the drive mechanism of a takeoff device.

12. Ath read store according to Claim 11, characte- rised in that the take-off device is formed by a thread take-up point arranged downstream of the thread store in the direction of thread travel.

13. Athread store according to one or more of Claims 1 to 12, with a thread connecting device arranged downstream of the thread store, characterised in that the thread guide is connected to both the thread store and the thread connecting device.

14. A thread store according to one or more of Claims 9 to 13, characterised in that the device for determining the rotational direction of the thread retaining ring is formed by a thread connecting device which is arranged between thread store and thread take-up point and is connected in terms of control to the drive mechanism of the thread take-up point.

15. Athread store according to one or more of Claims 12 to 14, characterised by a speed control device connected to the pulse counterfor controlling the speed of the thread take-up point as a function of the thread length located on the storage roll.

16. A thread store according to one or more Claims 9to 15, characterised in thatthefilling monitor is connected to a stopping device.

17. Athread store according to one or more of Claims 1 to 16, characterised in that the storage roll has at its discharge end a thread retaining device which is open radial ly outwards.

18. Ath read store according to Claim 17, cha racterised in that the thread retaining device is mounted lowerably in the storage roll.

19. A thread store according to Claim 18, characte- rised in thatthe thread retaining device is loaded elastically radial ly inwards and in that an axially movable adjusting cone is also provided in the storage roll and can be caused to act on the internal end of the thread retaining device.

20. A thread store according to Claim 19, characterised in that the thread retaining device is guided in the storage roll with security against rotation and bears on its internal end a small wheel which is orientated in the circumferential direction of the storage roll for supporting thethread retaining device on the adjusting cone.

21. Athread store according to one or more of Claims 17 to 20, characterised in that the storage roll projects beyond its discharge end in the form of a tapering truncated cone on whose surface area the thread retaining device is arranged.

22. A thread store according to Claim 21, characterised in that the thread retaining device is arranged in the immediate vicinity of the larger diameter of the 12 truncated cone.

23. Athread store according to Claim 22, characterised in that the thread retaining device is lowerable in the peripheral area of the truncated cone.

24. A thread store according to Claim 17, characterised in thatthe thread retaining device is part of a thread retaining ring which can be driven relative to thestorageroll.

25. A thread store according to Claim 24, characte- rised in thatthe storage roll as well asthe thread retaining ring are connected via a respective slip coupling to a common driving shaft.

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26. Ath read store according to Claim 25, characterised in thatthe storage roll as well as the thread retaining ring bear a respective hysteresis disc and a permanent magnet is arranged on the common driving shaft between the two hysteresis discs.

27. Athread store according to any of Claims 13to 26, characterised in that the thread retaining device is designed as a hookwhich has an open groove in the driving direction.

28. A thread store according to Claim 27, characterised in that the thread retaining device bears a ceramic insert in its groove.

29. Ath read store according to any of Claims 13 to 28, characterised in that the thread guide is designed as a thread supplier which brings the thread from a predetermined thread course into a thread course crossing the path of the revolving thread retaining device.

30. Ath read store according to Claim 29, characterised in thatthe thread guide consists of two thread guide members, which can be separated from each other.

31. Ath read store according to any of Claims 1 to 30, characterised in that the opening of a suction tube is arranged in the vicinity of the thread course of the thread fed to the storage roll.

32. Athread store according to any of Claims 1 to 31 with a thread connecting device arranged downstream of thethread store and with a devicefor producing andlor delivering a thread, characterised in that a thread controllerwhich is connected in terms of control to the device for producing andlor delivering thethread is arranged downstream of thethread connecting device in the thread course.

33. Ath read store according to Claims 31 and 32, characterised in thatthe thread controller is connected in terms of control to the rotary drive mechanism of the storage roll, the rotational direction of the rotary drive mechanism being reversible.

34. Athread store according to any of Claims 1 to 33 fora textile machine with a plurality of working stations and a maintenance device which travels past these working stations and which can be allocated selectively to these working stations, characterised in thatthe storage roll and the thread course can be brought into an acute angle relative to each other in such away that the discharge end 103 of the storage roll is located closerto the thread course than its feed end.

35. Athread store with rotary drive mechanism and a storage roll constructed substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

GB 2 128 213 A 12 Printed for Her Majesty's Stationery Office byTheTweeddale Press Ltd., Berwick-upon-Tweed, 1984. Published atthe Patent Office, 25 Southampton Buildings, London WC2A lAY, from which copies may be obtained.

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