US3400530A

US3400530A - Device for braking a train flyer on multiple twisting spindles

Info

Publication number: US3400530A
Application number: US638340A
Authority: US
Inventors: Heimes Willy; Grapp Hans
Original assignee: Palitex Project Co GmbH
Current assignee: Palitex Project Co GmbH
Priority date: 1966-05-17
Filing date: 1967-05-15
Publication date: 1968-09-10
Anticipated expiration: 1985-09-10
Also published as: DE1685940B1; ES340469A1; GB1186032A; DE1560256B1

Description

Sept. l0, 1968 w. HEIMEs ET AL DEVICE FOR BRAKING A TRAIN FLYER ON MULTIPLE TWISTING SPINDLES 2 Sheets-Shed l Filed May 15, 1967 IllIIIll/l /Mvfn/rafas -/e//ves Sept. l0, 1968 w, HEMES ETAL DEVICE FOR BRAKING A TRAIN FLYER ON MULTIPLE TWISTING SPNDLES Filed May l5, 1967 2 Sheets-Sheet 2 FIG. 4

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United States Patent O DEVICE FOR BRAKING A TRAIN FLYER N MULTIPLE TWISTING SPINDLES Willy Heimes, Krefeld, and Hans Grapp, Krefeld-Forstwald, Germany, assignors to Palitex Project-Company G.m.b.H., Krefeld, Germany Filed May 15, 1967, Ser. No. 638,340 Claims priority, application Germany, May 17, 1966,

P 39.458; Apr. 22, 1967, P 41,969 11 Claims. (Cl. 57-53.3)

ABSTRACT OF THE DISCLGSURE The present invention relates to a device for braking a train flyer -on multiple twisting spindles, which includes a train flyer having a bearing hub freely rotatable about the axis of the spindle shank, while friction surface means are provided below the train flyer for selective fristion braking engagement with said 'braking hu-b. The device furthermore comprises magnetic means respectively connected to the `spindle shank and the ybearing hub and operable selectively to move the bearing hub relatively toward and away from said friction surface means for selectively increasing and decreasing the frictional engagement of said bearing hub with said friction surface means and also for selectively `frictionaily disengaging said hub from said friction surface means.

The present invention relates to a device for braking a train flyer of multiple twisting spindles for twisting with overhead unwinding of the thread from a feeding bobbin at a standstill or from a plurality of feeding bobbins arranged axially one above the other, the threads withdrawn upwa-rdly being pulled axially through the hollow spindle shank in downward direction. In this connection, the hollow spindle itself may form the thread-guiding tube or may serve for receiving and holding a threadguiding tube. In the interior of the hollow spindle shank, the threads as a rule pass through a thread brake.

The said feeding bobbins are usually so-called crosswound bobbins with which the unwinding point of the threads from the main mantle surface moves continuously back and forth over the entire length of the bobbin. Since the unwinding force from the mantle surface of the bobbin at lan upper incline is directed inwardly, sometimes SO-called train flyers are employed as auxiliary means which first cause the thread or threads to move at an incline upwardly from the feeding bobbin so that the threads first are deviated in upward direction inwardly in the thread-guiding eye at the free end yof the train flyer, and thereafter are deviated downwardly into the hollow spindle shank.

By employing a train flyer with a thread-guiding eye at the free end, it is assured that the thread being withdrawn from the feeding bobbin cannot contact the upperouter edge of the bobbin, whereby otherwise a thread "break would be caused. Inasmuch as the unwinding point of the thread or the threads is in view of the crosswinding of the feeding 'bobbin continuously displaced over the length of the bobbin, the free thread length between the unwinding points for the deviations `differs and varies continuously. As a result thereof, the train flyer which is dragged -by the thread rotates in a jerky and non-uniform manner and may even run ahead of the thread, so that loops form. l

Among others, a train flyer has :been suggested, the thread engaging edge of which over an angle of 180 approximately follows the shape of a logarithmic spiral and at the end has a self-threading thread-guiding eye. Such a train flyer brings about the advantage that the thread withdrawn from the feeding bobbin when being threaded from above into the hollow spindle shank or thread-guiding tube, does not have from the very start to be inserted int-o the thread-guiding eye of the train flyer. Such insertion is not necessary at all. When the spindle starts rotating, the thread will automatically engage the thread-engaging edges of the train flyer, and while carrying along the train flyer, will move along the thread-engaging edge until the thread engages the thread-guiding eye, and thus is kept at a distance from the upper edge of the feeding bobbin so as not to Contact the latter.

In order with the above mentioned train flyers to assure a uniform rotation, the train flyer is subjected to a braking operation while the bearing hub of the train flyer engages an annular braking surface. However, the braking oper-ation will require different braking force, depending on the speed of the spindle and the type of threads being processed. These -braking forces are, with heretofore known and with the suggested multiple twisting spindles produced by the fact that the bea-ring hub of the train flyer is lplaced under a more or less high load, for instance, by mounting thereon rings as a weight so that the friction at which the bearing hub, during its rotation, engages the ybraking surface, will accordingly assume different values in conformity with the magnitude of the mounted weights.

The variation in the braking force by means of weights make-s possible a stepwise change in the conditions of friction. However, keeping the weights in preparedness and the selection of the necessary weights caused difliculties. The heretofore known solutions for changing the frictional conditions are, therefore, unsatisfactory.

'Starting with a train flyer, which in the form of a thread unwinding aid on multiple twisting spindles for the overhead withdrawal of threads from crosswound bobbins, Iby means of its lbearing hub, freely rotatably surrounds the hollow spindle 4shank and rests in a downward direction on a braking surface, it is an object of the present invention to provide a device for braking the train flyer in which the braking force can :be changed in steps or infinitely without the employment of additional weights.

It is another object of this invention to provide a device as set forth in the preceding paragraph, which will be able to relieve entirely, or nearly entirely, the braking surface from the bearing hub of the braking flyer so that i the conditions of circulation of the train flyer can be controlled in wide limits.

These and other objects and advantages of the invention will appear mo-re clearly from the following specification in connection with the accompanying drawings in which:

FIG. 1 illustrates a section through the upper end of a hollow spindle shank with inserted thread brake, and with a train flyer and a device for adjusting the braking force acting upon the train flyer.

FIG. 2 is a top view on the free end of the hollow spindle shank with a train flyer according to FIG. l.

FIG. 3 is a side view of the annular magnet carrier according to FIG. l.

FIG. 4 illustrates, partially in section and partially in view, the upper end of a hollow spindle shank with train flyer hub and annular magnet carrier of a different embodiment of the present invention.

FIG. 5 is a further embodiment of the present invention similar to that of FIG. 4, according to which the train flyer hub extends over the annular magnet carrier.

FIG. 6 is a section through the upper end of a hollow spindle shank with a train flyer freely rotating about said spindle shank, while on the bearing sleeve for said train flyer there is provided a thread brake.

FIG. 7 is a partial development of the arresting or indexing means of an arresting or indexing device.

FIG. 8 is a section through the thread brtke taken along the line VIII-VIII of FIG. 6.

The device for braking a train flyer, according to the present invention, is characterized primarily in that the bearing hub is adapted yby magnetic force to he pressed against the braking surface and is also adapted to be lifted off said braking surface up to approximately floating position.

Thus, in conformity with the present invention, the heretofore commonly employed weights for varying the braking forces have been replaced by magnetic forces which become effective on the bearing hub and furnish the necessary braking pressure or promote a complete, or nearly complete relief of the braking surface.

According to a further development of the present invention, the bearing hub may be provided with an annular magnetic body around which extends, with radial play, an annular magnet which is axially adjustably arranged at the free end of the hollow spindle shank.

Due to the cooperation of the annular magnetic body on the bearing hub of the train flyer with the annular magnet which is axially displaceably arranged at the free end of the hollow spindle shank, the pressing force at which the bearing hub is engaging the braking surface can be varied by displacing the annular magnet with regard to the annular magnetic body. Thus, in conformity with the change in the magnetic eld, the braking force can be increased or decreased, or the bearing hub on the braking surface can be eliminated entirely, or nearly entirely, by moving the bearing hub with the train flyer by magnetic force into a floating position.

More specifically, according to the present invention, the annular magnet may be arranged on an annular magnet carrier which is axially adjustably mounted at the free end of the hollow spindle shank.

If thus the annular magnet carrier with the annular magnet is more or less moved away from the braking surface, this displacement causes the bearing hub of the train flyer to be lifted olf the braking surface to a certain extent, in other words, brings about at least some relief so that the braking forces will be reduced or will be completely eliminated when the bearing hub is lifted ofl completely so that the bearing hub with the braking flyer will move into a floating position.

When the annular magnet carrier with the annular magnet is moved into the opposite direction, the magnetic forces will, through the intervention of the annular magnet body, press the bearing hub correspondingly stronger against the braking surface so that the braking surface will be increased and the thread will have to furnish more I power in order to take the train flyer along during its rotation.

According to a still further development of the invention, the bearing hub may unilaterally be extended through a bearing sleeve having mounted thereon the annular magnetic body, whereby the conditions are created which permit a different design for the bearing hub when employing uniform annular magnetic bodies, depending on how the bearing hub is placed upon the upper end of the hollow spindle shank.

According to a further development of the invention, the annular magnetic carrier may be arrestable at a number of different levels with regard to the hollow spindle shank. This may be effected by an arresting device so that during the operation, an undue displacement will not be possible. Moreover, there exists a possibility by means of an arresting device in combination with markings, to pre-adjust a certain desired braking value or to bring about the desired relief of the braking surface.

Still according to another feature of the present invention, the annular magnet carrier may be formed by a threaded bushing which extends around the free end of the hollow spindle shank. The said threaded bushing has, at that side thereof which is adjacent to the train flyer, connected thereto 4the said annular magnet. Also in this CII Cil

instance, the employment of an arresting device is possible in order to maintain the annular magnet carrier at certain threaded bushings.

According 4to still another feature of the present invention, the annular magnet carrier may be designed as a sliding bushing which surrounds the free end of the hollow spindle shank. This sliding bushing is spring biased, the force of the spring being directed toward the train flyer hub. The said sliding bushing rests by means of at least one radially directed pin on a step of an annular groove extending in steps around the hollow spindle shank. With this embodiment, the axial displacement and arresting of the annular magnet carrier is effected similar to ballpoint pins with which by means of guiding grooves and notches or the like, it is possible to move the end of the lead out of the pin against the thrust of a spring, and is also insertable by spring forces. However, there exists the difference that with the arrangement according to the present invention, not two positions, but a multiple of positions may be provided for the annular magnet carrier, which positions have associated therewith different braking forces.

If with the device according to the invention, a train flyer is provided, the thread-engaging edge of which follows approximately the shape of a logarithmic spiral and if such a device at the end thereof as a self-threading thread-guiding eye, it is possible according to the present invention, to design the annular magnet carrier in the form of a body which tapers in the manner of a paraboloid toward the free end of a hollow spindle shank, said last mentioned body having an annular magnet connected thereto. In this instance, the annular magnet carrier acts similar to the train flyer as an unwinding aid, namely, when the thread during its course has not yet entered the thread-guiding eye. In this instance, the thread could engage the upper edge of the feeding bobbin, but this is prevented by the annular -magnet carrier with a far protruding lower edge. The said annular magnet carrier, due to the paraboloid shape of its mantle surface, keeps the thread during the starting movement thereof away from the upper edge of the delivery bobbin and gradually leads said thread `to the deviating point of the free end of the hollow spindle shank into which the thread is pulled in downward direction.

If an annular magnet carrier is employed which has the shape of a paraboloid body, the annular magnet carrier may be designed as a hollow body and may, through openings in the mantle surface, give oil wetting and reviving substances as disclosed in U.S. Patent 3,295,305.

In order to be able to pre-adjust the braking force depending on the type of threads to be processed, it is possible according to the present invention to provide marks around the hollow spindle shank and on the annular magnet carrier, which indicate the level of the annular magnets with regard to the hollow spindle shank. I f the annular magnet body is, for instance by means of an adjustable thread, screwed onto the hollow spindle shank so that its position as to height is variable by turning the annular magnet carrier, the respective adjusted braking force may be indicated by markings at the upper edge of the annular magnet carrier, said markings having associated therewith a mark on the hollow spindle shank. Similar provisions may be made when the annular magnet carrier is designed as a sliding bushing which extends around the free end of the hollow spindle shank. In this instance, by markings on the annular magnet carrier and on the hollow spindle shank, it can be indicated at which arresting step of the annular magnet carrier and at which braking force an adjustment has been made. Thus, there is furnished the possibility of a pre-adjustment while at the same time, there is avoided the danger of an undesirable adjustment during the twisting operation.

According to the present invention, the device may also be so designed that it will, at the same time, also influence the thread pull through the hollow spindle shank. To this end, the invention provides that a thread brake is arranged on the bearing sleeve above the inlet end of the hollow spindle shank. This brings about that the device for braking the train yer simultaneously serves for braking the thread entering the hollow spindle shank, so that a special thread brake lwithin the hollow spindle shank is not necessary, which in itself is an important simplication in the servicing and assembling operation.

More specifically according to the present invention, a bearing support may be arranged on the bearing sleeve. In the said bearing support there are journalled the bearing studs of two thread braking discs known per se, which are pressed against each other by variable force. The mantle surfaces of said thread braking discs are tangent to the spindle shank so that the thread withdrawn from the feeding bobbin will, after passing through the threadguiding eye at the free end of the train yer, pass through the'brake which simultaneously deviates the thread into the hollow spindle shank. In this connection, it is ,of particular advantage that the bearing sleeve rotates with the train yer so that no rolling friction occurs on the thread, as is the case with a hollow spindle shank the free upper inlet end is at a standstill.

Referring now to the drawing in detail, FIG. 1 shows in dot-dash lines the feeding bobbin 1 with the yarn 2 wound thereupon. Within the feeding bobbin 1, there is shown the multisectional hollow spindle shank with the portion 3 directly surrounded by the feeding bobbin 1. Within the interior of said portion 3 there is located a thread brake of which there is shown the fixed brake ring 4 and the brake sleeve 7.

A truncated cone member 8 through which the threadguiding tube 9 extends is inserted into the lower end of the portion 3 of the hollow spindle shank. The base of truncated cone 8 has connected thereto a brake disc 10 on which the bearing hub 11 of the brake yer 12 rests. Bearing hub 11 is, by means of bearing sleeve 13, extended in upward direction. Bearing hub 11 rests, by means of radially inwardly protruding cylindrical slide surface 14, on the thread-guiding pipe 9 whereby a free and practically frictional circulation of the hub 13 of the train iyer 12 about the thread-guiding tube 9 will be assured.

The pressing force and thus, the braking force, of the bearing hub 11 on brake d-isc 10 may be varied by means of the annular magnetic body 15 which is mounted on bearing sleeve 13, and -by means of the annular magnet 6, which with radial play extends around the annular magnetic body 15, and to this end is connected in the carrier 17 for the annular magnet. Said carrier 17 has approximately the shape of a paraboloid which tapers toward the free end of tbe hollow spindle shank.

In this instance, the carrier or support 17 in the form of a paraboloid serves as an additional unwinding aid, namely when the thread, during the starting phase, is not located in the thread-guiding eye 24 at the free end of the train iiyer 12. The thread-guiding eye 24 is, in view of the curvature of the wire forming said threadguiding eye or in view of the type of the various angled portions, a self-threading eye into which the thread which rst engages the thread-contacting edge 25 of the train flyer 12 will automatically pass after sliding along said edge 25.

In order to assure that the thread while circulating and carrying along the train yer 12 will gradually pass along edge 25 and move outwardly, the thread engaging edge' 25 has the s-hape of a logarithmic spiral which starts at the bearing hub 11.

For purposes of facilitating the thread circulation when the thread, during the starting phase of the spindle, passes along the mantle surface of the annular magnetic carrier 17, the mantle is provided with the spiral shaped groove 23.

The annular magnet carrier 17 in the form of a paraboloid may, in conformity with FIGS. 1 to 3, be designed as a hollow 'body which in the interior thereof has a wetting means, or a iinishing preparation, which through openings leading into grooves 23 passes outwardly and wets the thread during the rotation thereof. In this way, the thread is, prior to its twisting operation proper in the spindle, subjected to wetting or to the treatment by a finishing operation.

As will be seen in FIG. 1, the annular magnet carrier 17 is, by means of the thread 18, screwed onto the extension 19 of the part 3 of the hollow spindle shank so that the location of the annular magnet 16, with regard to the hollow spindle shank, can be varied by turning the annular magnetic carrier 17.

If, for instance, the annular magnetic carrier 17 is so rotated that it is being displaced toward the free end of the hollow spindle shank, the annular magnet 16 'brings about a corresponding displacement of the bearing hub 11, which will thus at a reduced pressure, press upon the braking disc 10 or will even in a floating manner be lifted oft said disc 10.

By turning in the opposite direction, the annular magnet 16 will, through the intervention of the annular magnetic body 15, bring about that the bearing hub 11 will be closer to the breaking ring 10 or will be pressed thereagainst whereby the braking eiect impeding the rotation of the train yer 12 will be increased.

The adjustment of the annular magnet 16, by turning the annular magnetic carrier 17, can be effected in a very tine manner, especially if the thread 18 is designed as a -ne thread.

According to FIG. l, provision is made to the effect that the annular magnetic carrier 17, after a certain angle of rotation, is held by an arresting device with which a further turning requires the overcoming of the thrust of a spring. To this end, all the way around the extension member 19 of part 3 of the hollow spindle shank, there are -distributed longitudinal grooves 20 adapted to be engaged by a ball 21, which is continuously biased by a spring 22. It would thus be assured that the annular magnetic carrier 17 will not actually be displaced and that instead, a turning, i.e. an axial displacement, requires the displacement of the ball 21 out of a groove 20. Thus, the oating condition or various braking positions can be pre-set, to which end, as indicated in FIG. 2, the upper end or marginal portion of the annular magnet carrier 10 is provided with markings a, b, c, for cooperation with the marking d on the extension member 19 of the part 3 of the hollow spindle shank.

FIG. 4, partially in section and partially in view, illustrates a mo-died arrangement of a device, according to the invention, for breaking the train flyer. Similar to the preceding embodiment, the truncated cone 8 mounted on the thread-guiding tube 9 has mounted on its base surface the brake disc 10a, labove which there is loca-ted the bearing hu-b 11 with the train flyer 12. The annular magnetic body 15 is mounted on the bearing sleeve 13 which similar to the construction of the above described embodiment, by means of two rounded bearing surfaces 14, extends around the thread-guiding tube 9 with bearing play. The annular magnet 16 extends co-axially and with radial play about the annular magnetic body 15. The magnet 16 is surrounded by the annular magnet carrier 26 designed as a sliding sleeve. The magnet carrier 26 extends displaceably with slide iit around the inner portion of a bearing cap 27 mounted on the free end of the thread-guiding tube 9. Cap 27 has a U-shaped cross section with the legs of the U extending downwardly. The inner leg 28 rests on the thread-guiding pipe 9, whereas the outer leg 29 with radial play extends around the magnet carrier 26 designed as sliding bushing.

The magnet carrier 26 is provided with the radially inwardly protruding arresting pin 30. There also exists the possibility of providing a plurality of pins 30 uniformly distributed all the way around. The free end 31 or the arresting pin 39 extends into a groove 34 in the leg 28 of cap 27. The groove 34 extends all the way around in steps 33, so that a plurality of steps 33 distributed over the circumference is available on which the pin 30 can rest by means of its end 31. In this way, the magnetic ring carrier 26 may be set for various heights or levels. The magnet ring carrier 26 is held on the various steps 33 by means of a spring 32. On the other hand, the carrier 26 rests on cap 27 on the base legs thereof.

With this embodiment, markings may Ibe provided, on one hand, on `the said carrier 26 and on the other hand, on leg 29 of cap 27. These markings are associated with the various steps 33 of groove 34 in leg 28 of cap 27.

According to the position of the carrier 26 in FIG. 4, said carrier, through the intervention of annular magnets 15, has lifted the bearing hub 13 with train ilyer 12 olf the braking disc 10, so that the latter is held in a floating condition. The bearing hub 13 will thus be braked exclusively by the friction of rotation of the bearing surface 14 of bearing hub 13 on thread-guiding tube 9.

When the annular magnet carrier 26 is displaced downwardly, the bearing hub 11 is pressed against the braking disc 1G at greater or lower pressure, the maximum braking force occurring when the magnetic ring carrier 26 moves into position (shown in dash lines).

The embodiment of FIG. 5 corresponds to that of FIG. 4, with the difference that the bearing hub 11 is provided with a sleeve, the cross sectional shape of which corresponds to the cap 27 of FIG. 4. The inner leg is formed by the bearing sleeve 13 with the bearing surfaces 14, by means of which the hub 13 extends around the thread-guiding tube 9. The bearing hub 11 thus extends around the outermost free end of the thread-guiding pipe 9.

The bearing sleeve 13 forming a part of the bearing hub 11 may have its braking surface 35 be brought into engagement with braking disc by displacing the annular magnet carrier 26 downwardly, which latter is in the form of a sliding sleeve. Carrier 26, by means of its annular magnet 16, extends around the bearing sleeve 13 and the magnetic ring thereof, and also extends around the cylindrical section 36 of truncated cone 8 with slide fit. In the cylindrical section 36 of the truncated cone S, there is provided, in conformity with FIG. 4, a step-shaped annular groove 34. The free end 31 of the arresting pin can rest on any of the steps 33. Pin 30 is connected to the magnetic ring carrier 26 and by means of its free ends 31, engages the groove 34. Also, with this embodiment, a spring 32 axially engages the annular magnet carrier 26, said spring having its outer end resting on the truncated cone 8.

An upward displacement of the carrier 26 brings about relief of the braking disc 10 and thus leads to a lifting off of the bearing hub 13 from the braking disc 10. Correspondingly, a downward displacement of the carrier 26 magnetically brings about a more or less strong engagement of the braking surface of bearing sleeve 13 with braking disc 10.

In conformity with FIG. 4, also with the embodiment of FIG. 5 it is possible by markings on the carrier 26 and truncated cone 8, to effect a pre-setting -of the braking force or a certain floating position of the bearing hub 11 with the train flyer 12.

Similar to the preceding embodiments, it is also possible to effect the braking of the train flyer 12, which does not have to be of the design shown in FIG. 2, within wide limits, while there also exists the possibility of limiting the braking to the slide friction of the bearing hub 13 on the thread-guiding hub 9.

The device for braking the train llyer 12, according to FIGS. 6 to 8, is designed in a manner similar to that in FIG. 5. A portion of the hollow spindle shank is formed by the insert member, which has its lower end designed in the form of a truncated cone 8 and through which extends the thread-guiding tube 9. Connected to the upper end face of the insert member 8 is the braking'disc 10 on which the bearing hub 11 of the braking illyer 12 rests. Above the braking tlyer plane, the bearing hub is designed as a doubleewalled bearing sleeve 13', the inner wall on the outside thereof supporting the annular magnet body 15. The bearing sleeve rests on the thread-guiding tube 9 b; means of the radially inwardly protruding annular sliding surface 14 whereby a free and almost frictionless rotation ofthe bearing sleeve 13 of train flyer 12 around the threadguiding tube 9 will be assured.

For purposes of changing the pressing force and there by the braking force of the bearing hub 11 onV the braking disc 10, the bearing hub 11 may have its braking surface 35 brought into engagement with thef'braking disc 10 by downwardly moving the sliding sleeve 26, which has its inner side provided with the annular magnets 16.

During this downward displacement, the annular magnets 16 pull the magnet body 15 -and thus, the bearing hub 11, or bearing sleeve 13, downwardly and press the latter-against the braking disc 10. f

yThe sliding sleeve 26 extends, With play, around not only the inner wall of the bearing sleeve 13 but simultaneously with radial play, also around the upper free end of the insert body 8 of the hollow spindle shank. The cylindrical section 36 of the insert body 8 has a step 37 against which the spring 32 rests, which has its other end resting on the step 38 of the sliding sleeve 26. Spring 32 urges the sliding sleeve 36 with the magnet ring 15 to move in upward direction. The position of the `sliding sleeve or the location of thrust of spring 32 can be fixed by means of the arresting pin 30 in the sliding sleeve 26. Pin 3@ extends radially inwardly into one or yanother arresting slot 39 of the arresting sleeve 40, which is mounted on the upper end of the cylindrical section 36 of the insert body 8. Depending on the yslot 39 which is engaged by pin 30, which is made possible by turning the sliding sleeve 26, the magnet ring 15 will thus be located more or less close to the magnet 16 in the bearing sleeve 13 so that braking forces can be realized which vary'by steps, and with which the bearing hub 11 of the train yer 12 engages the braking disc 10.

The lu'gher the sliding sleeve 26 is located, the less will be the braking force which in the highest position even leads to a lloating position of the train flyer hub 11,` so that the train flyer will be able to move practically free from friction when disregarding the friction of rotation on the thread-guiding tube 9.

The bearing hub 11 extends unilaterally upwardly and forms a bearing support for the bearing studs 41, according to FIGS. 6 and 8, t-wo

braking discs

42 and 43 being mounted on the bearingstud 41. The braking disc 42 is xed on bearing stud 41 as to its position, whereas the second braking disc 43 is axially displaceable, and by the thrust of spring 42 is pressed against the braking disc 42. Spring 44 rests by means of its other end on the bearing bushing 45, which receives the bearing stud 41The bearing bushing 45 can [be axially displaced, in View of the fact that its pin 46 engages the arresting slots 47 of the bearing support, so that by pressing pin 46 into one of the arresting slots 47, the bearing bushing 45 is displaced more or less along the bearing stud 41 within the bearing support whereby the adjustment of the force of the spring 44 will be made possible. The other end of the bearing stud 41 is fixed as to the other side of the bearing support.

Similar to the manner in which the train flyer 12 is rotated by the thread during its withdrawal from the delivery bobbin, also the bearing block mounted on the bearing hub or bearing sleeve will rotate together with the braking discs 42 and `43 so that the thread solely between the

discs

42 and 43 about the bearing stud 41 is deviated downwardly and is practically not exposed to any friction. This applies vin part when also the bearing stud 41 is freely rotatable, which meansis freelyvrotatablyjournalledin the bearing supports -at its end 48.

By means of the device illustrated in the drawing, according to FIGS. 6 to 8, it is assured that also without any dissembly of the hollow spindle shank, merely by steps at the free end of said hollow spindle shank, not only the braking effect on the train fiyer can be changed, but also the braking of the thread when the latter passes through the hollow spindle shank, so that thread brake within the hollow spindle shank will be superuous.

It is, of course, to be understood that the present invention is, by no means, limited to the particular constructions shown in the drawings, but also comprises any modifications within the scope of the appended claims.

What we claim is:

1. 'In combination with a hollow spindle shank of a multiple twist spindle including a thread-guiding tube: a -train flyer having a bearing hub freely rotatable about said thread-guiding tube, means having a friction surface extending around said thread-guiding tube and arranged below said train flyer for selective frictional braking engagement with said bearing hub, an-d magnetic means respectively connected to said spindle shank and said bearing hub and operable selectively to move said bearing hub relatively toward and away from said friction surface for selectively increasing and decreasing the frictional engagement of said bearing hub with said friction surface and also for selectively frictionally disengaging said hub from said friction surface.

2. A device according to claim 1, in which said magnetic means includes first annular magnet means mounted on said bearing hub and also includes second annular magnet means extending with play around said first magnet means and being axially adjustably arranged on said spindle shank.

3. A device according to claim 2, which includes a support coaxially arranged on one end portion of said spindle shank and carrying said second annular magnet means, said support being adjustable in the axial direction of said spindle shank.

4. A device according to claim 2, in which said bearing hub has an axial extension in the form of a sleeve extending around said thread-guiding tube and supporting said first magnet means.

5. A device according to claim 3, which includes arresting means associated with said support for selectively holding the latter at any one of a plurality of levels.

6. A device according to claim 3, in which said support is formed by a threaded sleeve threadedly engaging one end portion of said spindle shank, that end portion of said threaded sleeve which is adjacent said flyer carrying said second annular magnet means.

7. A device according to claim 3, in which said support is formed by a sliding bushing coaxial with said spindle shank, said spindle shank within the range of said sliding bushing being provided with peripheral groove means extending around said spindle shank and having a plurality of resting steps, spring means continuously urging said sliding bushing into the direction toward said bearing hub, and pin means supported by and slidably mounted in said sliding bushing in a direction transverse to the axial direction of said sliding bushing, said pin means being operable selectively to be Irested on said steps.

3. A -device according to claim 3, in which said train flyer has a thread-engaging edge following approximately the contour of a loga-rithmic spiral .with a self-threading thread-guiding eye at the outermost end portion of said spiral, and in which said support has an outer contour approximately following the contour of a paraboloid, said second annular magnet means being arranged at that end portion of said support which is adjacent said train flyer.

9. A device according to claim 3, in which said support and said spindle shank are provided with markings for indicating the relative adjustment of said support and thereby said second annular magnet means with regard to said spindle shank and thereby also the level of said second annular magnet means with regard to said spindle shank.

10. A device according to claim 1, in which said bearing hub has an upwardly directed extension extending beyond the upper end of said thread-guiding tube, and thread-'braking means supported by the upper end of said extension for braking a thread entering said thread-guiding tube.

11. A device according to claim 1), in which said threadbraking means comprises a bearing stud supported by said extension and two thread-braking discs supported by said bearing stud and means for pressing said discs against each other at variable pressure, the mantle surface of said bearing stud being tangential to the longitudinal axis of said thread-guiding tube.

References Cited UNlTED STATES PATENTS 2,871,648 2/1959 Vibber 57-58.83 XR 3,165,882 l/l965 Kreuschmer 57'58.83 3,347,035 10/1967 Ellison et al. 5758.83 XR FOREIGN PATENTS 1,327,482 4/1963 France.

92,114 9/1959 Holland.

OTHER REFERENCES Volkman & Co.: German, Das 1,091,466, Oct. 20, 1960 57/ 5 8.83.

FRANK I. COHEN, Primary Examiner. W. H. SCHROEDER, Assistant Examiner.