US2304712A

US2304712A - Winding machine with auxiliary device for initiating the winding operation

Info

Publication number: US2304712A
Application number: US223369A
Authority: US
Inventors: Siegenthaler Walter
Original assignee: Firm Scharer Nussbaumer & Co
Current assignee: Firm Scharer Nussbaumer & Co; Firm Scharer-Nussbaumer & Co
Priority date: 1937-10-28
Filing date: 1938-08-05
Publication date: 1942-12-08
Anticipated expiration: 1959-12-08
Also published as: DE694234C; DE683139C; CH200341A; GB505947A; FR838563A; CH203309A

Description

WINDING MACHINE WITH AUXILIARY DEVICE FOR INITIATING THE WINDING OPERATION Dec. 8, 1942. w SIEGENTHALER 2,304,712

1 Filed Aug. 5, 195a 2 sheets-$1185; 1'

Dec. 8, 1942. w. SIEGENTHALER 2,304,712

WINDING MACHINE WITH AUXILIARY DEVICE FOR INITIATING' THE WINDING OPERATION Fi led Aug. 5, 1958 2 Sheets-Sheet 2 w lly/fling,

Patented Dec. 8, 1942 WINDING MACHINE WITH AUXILIARY DE- VICE FOR INITIATING THE WINDING OP- ERATION Walter Siegenthaler, Erlenbach, Switzerland, as-

signor to the firm Scharer- Nussbaumer & 00., Erlenbach, Switzerland Application August 5, 1938, Serial No. 223,369 In Switzerland October 28, 1937 '7 Claims;

This invention relates to winding machines. which. are provided with an auxiliary device. for initiating the winding operation and in which every time on completion. of a winding the fullbobbin is removed from the winding position while an empty bobbin is moved into this position.

The present invention comprises improvements in the apparatus disclosed in my U. S. Patent No. 2,131,147.

According to the invention the thread or yarn is wound by means of. a stationary guide in a terminal winding during the end period of the winding operation at a point remote from the tip of the bobbin, which is accordingly deter-- I mined, and is moved during the gyratory movement of the bobbin within the operating range of a gripper member which. deflects the yarn laterally by efiect of its own movement and thus. conveys the thread within the range of a moving thread catch by which. it is caught for then being directed onto the next bobbin to be wound...

By this means the productionof bobbins of the kind previously described is rendered possible in simple manner, in which the terminal winding is located in more or less close proximity to the tip of the bobbin, that is, spaced apart from the base of the bobbin. This. facilitates particularly the unwinding of the end of the thread at the tip of the bobbin as compared with bobbins wound by automatons in which the terminal winding is located at the base of the bobbin and in which the unwinding of the thread at the.

retaining rings arranged. on the base is rendered more difiicult and the thread end easily tangles. 73v

with the base and is then broken.

An embodiment of the invention in the form of a cop winding machine comprising a displace-- able and revoluble cop supporting frame is illustrated in the accompanying drawings in which Fig. 1 is an elevational view showing the position of the cop supporting frame prior to the completion of a winding;

Fig. 2 is a similar view showing the cop sup porting frame in a position which it assumes in the end stage of the winding operation;

Fig. 3 is a vertical section on the lin III-II1 in Fig. 2;

Fig. 4 is an elevational view showing the cop supporting frame pushed back into initial position but still rotating;

Fig. 5 is a vertical section on the line V-V in Fig. 4; Fig. 6 is a view similar to Fig. 4 except that the cop supporting frame is turned further;

Fig. 7 is a. vertical section on. the line. VII-47Hv In Fig. 6

Fig. 8 is a vertical section on the line lII.

in Fig. 6;

chine frame.

Figs. 9 and 10 each show a diiferent elevation. of an example of a driving head of the winding spindle in operative condition;

Figs. 11 and 12 each show a different View of this driving head in inoperative condition, Fig.

-' 12 being a section on the line. XIIXII in Fig- 11;.

Fig. 12a is a planview of a cop tube mounted. in the driving head of a spindle;

Fig. 13 is. a partial elevation of a winding Inachine provided with such spindle driving heads;

Fig. 14 is an elevation of a second example. of a spindle driving head;

Figs. 15 and 16 each show a section on theline XV-XV in Fig. 14 and XVIXVI in Fig. 15 respectively;

Figs. 1'7 and 18 each show a different. elevation. of a third example of the spindle driving head in. operative condition;

Fig. 19 is a front elevation depicting the inoperative condition of this spindle driving head;

Figs. 20 and 21 each show a further example. of a spindle driving head inoperative condition;

Fig. 22 is a section on the line XXII-XXII in Fig. 21; and

Fig. 23 shows a front elevation of this spindle driving head in inoperative condition.

In the example represented by Figs. 1. to 8.

the cop supporting frame is provided with two face plates I, 2 which are interconnected by a. hollow shaft 3 by means of which the cop support-' ing frame is mounted on a fixed bearing shaft 4. The cop supporting frame. is advanced step by step longitudinally of the bearing shaft 4. in the.

direction of the arrow I in Fig- 1 in a manner known per se during the building of the cop with. the aid. of a feeler (not shown) in dependence of the cop winding under formation. The, frame,- advancing means is similar to that disclosed in my U. S. Patent No. 2,131,147, wherein it comprises principally the motor driven screw spindle l2 and threaded coupling member II. The face plate I has two projecting arms I, I", which extend in the plane of the platev and serve for alternate cooperation with a longitudinal rail (not shown) arranged in the lower part 5 of the ma- Such a rail is shown in my U. S. Patent No. 2,131,147 where it is indicated by reference numeral 13.

The arm of the face plate 1 which extends downwardly cooperates with the longitudinal rail which serves as a stop for this arm, thereby presage to the abutment I'B (Fig. 8).

venting the cop supporting frame from rotational displacement. The face plate 2 is provided, in a manner similar to that described for the face plate I, with two projecting

arms

2, 2" which extend in the plane of the plate and serve for cooperation with the said longitudinal rail.

On the pair of plates I, 2' are mounted two winding spindles 6, 6' in diametrically opposed relation, each spindle being constructed as a roller, the roller of the upper winding spindle 6 which assumes the winding position (Figs. 1 to 3) being rotated by bearing engagement with an endless driving belt (not shown) which passes over the same. A driving means comprising endless belt I suitable for driving the spindles is shown in my U. S. Patent No. 2,131,147. Each one of the winding spindles 6, 6' is provided at its end projecting beyond the face plate I with a driving head I, I respectively provided with an inner elastic and thus resilient holding device 28, 52 (Fig. 12a) for the reception of cop tubes 8, 8' respectively the other ends of which are received in rigid or

resilient abutments

9, 9 respectively of a counter holding device Ill. The cop tubes can be removed individually from their mounting means by exerting pressure thereon in corresponding manner.

The counter holding device I is firmly connected to the face plate I by a tube II through which passes the bearing shaft 4 and thus forms a component part of the cop supporting frame. In the counter holding device II) are arranged two books I2, I2 which are coordinated to the winding spindles in diametrically opposed relation and serve as temporary stationary guides for the thread. During the operation of the machine the oncoming winding thread A passes over a thread guide I3, which corresponds to thread guide 35 of my Patent No. 2,131,147, and which reciprocates through a certain range corresponding to the length of the conical part of the cop winding in progress of formation, as indicated by the double arrow in Fig. 1. j

To each winding spindle 6, 8' is correlated a gripping member in the form of a barbed needle I4, I4 respectively the shanks of which are longitudinally displaceably guided in the face plates I I, 2 and which are loaded by compression springs I5, I5 respectively. As shown in Fig. 1,' the barbed needle I 4 rests with its smooth end against an abutment I6 fixed to the bearing shaft .4 and projects through a semi-circular recess in the circumference of a disc I! which recess gives pas- The disc !'I against which the barbed needle I4 abuts with its smooth end, is mounted onthe cop supporting frame together with an arm I8, as is evident from Figs. 1 and 2. This arm I8 bears laterally on the lower part 5pof the machine frame by means of its free end. The disc I1 is secured to the hub I8 of arm I8 by any suitable means such as screws I1, and the disc I! and arm I8 are mounted for relative rotation on a reduced extending bearing portion 3 of shaft 3. The arm I8, which corresponds to arm III in my Patent No. 2,131,147, and the disc II do not share in the rocking movements which the cop supporting frame performs for the purpose of removing the full cop tubes from the winding position and conveying the empty cop tubes into the winding position.

In feeding the cop supporting frame step by step in the direction of arrow I in Fig. 1 the cop counter holding device I0 approaches the barb of.the barbed needle I 4 abutting the stationary abutment It more and more. In the final winding phase the oncoming thread slides along the contact hook I2 and passes through the open hook end thereinto, so that, at the corresponding points of the spool the thread is wound in some parallel windings if, after producing the winding proper, the carriage is rotated in order to change the spool at the operative (winding) position, wherein the thread lies in the elbow of the contacthook I2 and the wound spool turns further about its own axis by reason of its inertia, whereby a final winding of parallel threads is produced on the spool.

At the moment of completion of the cop winding proper the projecting arm I of the face plate I registers with a notch in a longitudinal rail (not shown) provided in the lower part 5 of the machine frame, whereas the arm 2 of the face plate 2 registers with a corresponding notch, whereupon the cop supporting frame is rocked round the bearing shaft 4 through half a revolution, preferably automatically (by means notshown), in the direction of the arrow shown in Fig. 3. The means for performing this rocking operation is disclosed in my U. S. Patent No. 2,131,147 where the belt I serves to supply the actuating force, and slotted abutment bar I3 limits th rocking movement. Simultaneously with this rocking movement the cop supporting frame is longitudinally displaced relative to the bearing shaft 4 by spring action, whereby it is returned into initial position. The means for performing this longitudinal return movement is disclosed in my U. S. Patent No. 2,131,147, wherein it comprises principally spring I9 and arm II).

By effect of this rocking movement of the cop supporting frame the winding spindle B is rocked out of the winding position together with the full cop 8 and instead the winding spindle B carrying an empty cop tube 8 is rocked into this position in which it is immediately driven by the endless driving belt by frictional engagement therewith. The rocking movement of the cop supporting frame during which

thecop tubes

8, 8 perform a gyrating movement is limited by the arms I" and 2" of the face plates I, 2 hitting the above-mentioned lower longitudinal rail (not shown), whereby the cop supporting frame is secured in its new position of adjustment at the same time. I

Prior to the beginning of the rocking movement of the cop supporting frame the barbed needle I4 will have been ejected by cooperation of its smooth end with the abutment I6 through the semi-circular recess in the circumference of i moved into registration with the said recess or the stop disc I! and is passed through this re'- cess of the stop disc I! by action of its compression spring I5 (Fig. 6). During this rocking movement of the carriage through 180 bywhi-ch the spindle 8 is carried from winding position (Figure 1) to doffing position (Figure 6), the

barbed needle I4 grips, by means of the hook thereof, the thread portion passing between the thread guide I3 to the full cop tube 8, that is, to

the stop I2, which thread portion is thus laterally defiected by the barbed needle I4 in the manner shown in Fig. 6 to such an extent that the thread is moved on the path of movement of a thread catch l'9 provided on the head I of the winding spindle 6 so that the thread is caught by this thread catch and firmly clamped to the said head i by clamping action of the thread catch in order to be then wound on the empty cop tube 8'. The return movement of the frame is performed by means similar to that disclosed in my U. S. Patent No. 2,131,1 3? wherein it comprises particularly draw spring l9.

Due to the tension set up in the thread, owing to the winding spindle 6 carrying the full. cop tube 8 continuing rotating by inherent kinetic energy, the thread is broken between the two spools 8, 8', whereby the complete winding provided with a terminal winding may be disconnected from the head 1 of the spindle. The cop supporting frame then moves again from its initial winding position (Figure 6) to a position toward the right during which motion the needle I4 is also carried toward the right and comes to bear on the abutment IS. The full cop tube 8 inserted in the driving head of the winding. spindle 6 is then interchanged for an empty cop tube, whereupon the cycle of the operations explained is repeated.

In the end period of the operation for winding the cop tube 8'- for efiecting the terminal winding the thread guide [2' is rendered effective and during the subsequent half turn of the cop supporting frame the barbed needle M deflects the thread laterally so that it is caught by the thread catch 19 of the head 7 of the winding spindle B, then moving into winding position, and is secured to said head, whereupon the thread is wound onthe empty cop tube having been inserted in this head.

The hook-like thread guides l2, l2 arranged on the thread holding device Hi may be of more or less length or be adjustable in order to provide for effecting the terminal winding at a point of the cop tube as desired.

The spindle driving heads hereinafter described are provided with a clamping element which is urged against a counter surface by action of centrifugal force while the cop tube rotates, for the purpose of retaining the threadhaving been inserted between the clamping element and the counter surface at the time of the interchanging of cop tubes, which retaining effect endures until the cop tube stops moving.

By this means the result is obtained without any further provisions that when the complete- 1y wound, stopped cop tube is released from its mounting means it drags the thread end having been kept back at the place of clamping along so that no thread waste is retained at the place of clamping and this place is therefore free from thread waste at all times. Consequently, the completely wound cop tube is in no way prevented by the thread material, that is, thread waste, from moving out of engagement with the mounting means thereof, there being thus no risk of the cop tube getting stuck.

Figs. 9 to 12, different views of a spindle driving head are shown, which head for the purpose of fastening the same to the winding spindle 6 (Fig. 13) is provided with a bore 24 in an. inner partition wall 23 thereof (Fig. 12).. The hollow space 25 of the spindle driving head is provided with a holding device for the reception of cop tubes 8, 8' respectively (Figs. 12a andlB) The space 25 of the spindle driving head is provided at the respective end with an enlargement 2'? in which a curved leaf spring 28 is arranged one head Ia by means of a screw. 29 and the other end carries a weight 39 on the inner side thereof. When the spindle head is at rest, the correspondingly curved leaf spring 28 assumes a position as shown in Figs. 11 and 12. In this position, the

leaf spring 28 recedes for the major part of its length toward the free end thereof from the wall enveloping the enlargement 21. This wall is provided at its front end with a recess 3i extending over a certain circumferential length, one circumferential end of which recess terminates in a slot catch 3| for the thread. A prong 552 limiting this slot towards the 'front end of the wall is somewhat deflected outwardly from the remainder of the wall, enveloping the space 2?, as shown in Figs. 10 and 11. In Fig. 12a, which shows a cop 8 in the winding head la and th winding head mounted on the winding spindle ii, the spindle 6 is represented as being supported in ball bearings in bearing support head at on face plate I. Inside, the head la is provided with a spring 28 and also a holding device comprising an insert 52 of hard rubber having a conical bore for receiving the end of the cop tube. This insert 52 lies against an intermediate disc 5-3 of such thickness that the foot of the bobbin lies in spindle head la at such depth that the winding thread will lie at the proper position at the beginning of the winding operation. The disc 53 is exchangeable for discs of different thick ness.

machine, the spindle driving head is turned in the direction indicated by the arrow in Fig. 10,

the leaf spring 28 weighted at its free end swingsoutwardly over the full length thereof, by actionof centrifugal force, onto the wall portion of the; spindle driving head enveloping the space 2'? all around, as shown in Fig. 10. In this way the re cess 3| provided in this circumferential wall portion is bridged for acorresponding width, that is, limited at the front side, by the leaf spring 28 which, however, does not extend all the way up end of which is connected to the spindle driving to the front end of the spindle driving head la,

If thereupon .the winding thread 33 is brought within the range of the spindle driving head Ed by being accordingly deflected laterally (as regards the course of the thread), so that the thread is caught by the prong 32 acting as a thread catch and is moved along the slot 35 by means of this rong, the thread then comes to lie be tween the leaf spring 23 and the wall of the spindle driving head where it is clamped sufficiently in order to be subsequently directed over to the empty cop tube inserted in the spindle driving head and to be wound thereon. In clamping the thread between the leaf spring 23 and the wall of the spindle driving head la the thread is cut by effect of the thin and thus sharp outer edge of the leaf spring 28 and is thus severed from the full cop tube.

As shown in Fig. 13, the full cop tube 8 is moved out of winding position by effect of the rocking movement of the cop supporting frame and an empty cop tube 8' is moved into this position. During effecting this operation of interchanging cop tubes the barbed needle it, which has been accordingly controlled in automatic manner, has moved. the winding thread with.- in the range of the spindl driving head '50. on the winding spindle 5. Since this winding spin dle 6 is driven in the position. of the cop sup-- porting frame shown, the winding thread arriv. .ing from the thread guide is is subsequently;

When, during the operation of the winding caught by the prong 32 of the spindle drivin head, whereupon the thread is severed.

After the winding spindle concerned has come to rest on the completion of the winding and the subsequent operation of interchanging cop tubes, the leaf spring 28 assumes its condition of inoperation again in which the clamping action between the leaf spring 28 and the wall of the spindle driving head 1a serving as a count-er surface therefor, in an amount as required for retaining the corresponding thread portion, ceases. In consequence thereof the thread which previously had been retained by the leaf spring 28 can be pulled out of the spindle driving head without any further provisions by the full cop tube, when the latter is released from engagement with the bearing means thereof.

Therefore, the thread is not retained in the spindle driving head so that no thread waste can accumulate in the latter. This makes it possible, on the other hand, to effect a smooth delivery of the thread to the clamping point of the spindle head and a more secure attachment and of securely clamping threads of any size varying between the thickest and thinnest threads.

In the example shown in Figs. 14 to 16, into an outer circumferential groove 40 of the spindle driving head 1b is inserted an open ended ring 4| which is provided at one end with a projecting arm 42 serving as a thread catch. As evident from Figs. 15 and 16, the portion of the ring 4| adjacent the end thereof which forms the thread catch bears closely against the spindle driving head for a distance of over half the circumferential length, whereas concerning the remaining portion of the circumference. of the ring 4|, clearance is provided between the rin and the spindle driving head 1b, in consequence whereof it is evident that the bearing of the ring 4| against the spindle driving head 1b is non-uniform to a corresponding extent. This unequal bearing engagement between the rin 4| and the spindle driving head 1?) is maintained due to a consequent weight distribution of the ring 4| by action of centrifugal force, when the spindle driving head rotates, so that as the winding thread is caught by the catch arm 42 of the ring 4| it is clamped between the ring 4| and the spindle driving head, whereupon the operation of severing the thread arriving from the full cop tube takes place.

After the spindle driving head has come to rest, on the completion of the winding and the subsequent operation of interchanging cop tubes,

and thus stops turning, the ring 4| is urged against the spindle driving head 1b merely by action of its ownweight and thus no longer with considerable force, so that the thread which is then retained by the ring only slightly can easily b pulled off the spindle driving head 11). 1

In the examples hereinafter described-by talcing reference to Figs. 17 to 23, the spindle driving head is provided with a rigid clamping element which during the operation of thewinding 7 machine is moved by action of centrifugal force from inside to outside, due to being correspondingly arranged, whereby it is urged against the counter surface. J

By this means, the result is obtained that with the aid of simple, altogether unsusceptiblemeans which warrant a reliable operation in the long run the thread can be temporarily retained.

In the example shown in Figs. 17 to 19, in the enlargement 21 of the spindle driving head 10 a rigid arcuate wing 43 is pivotally mounted by means of athreaded stud 44. When the spindle head does not rotate, thewing 43 assumes, for example, a position as shown in Fig. 19. In this position the wing 43 bears with its reduced end adjacent the threaded stud 44 against the cir-; cumferential wall limiting the enlargement 21, whereas the remaining part of the wing recedes over its full length inwardly away from the said circumferential wall.

As the winding spindle provided with the spindle driving head is rotated in the direction of the arrow indicated in Fig. 18, the wing 43 swings by action of centrifugal force from inside to outside, so that it bears against the inside of said circumferential wall over the major part of its length, as indicated in Fig. 18. In this way the recess 3| provided in the circumferential wall is bridged, that is, limited at the front end by the wing 43 for the width of the same. If then the winding thread 33 is so moved within the range of the spindle driving head 10 by being accorde ingly deflected by means of the barbed needle I4? that it is grasped by the prong 32 serving as a thread catch and is moved by the latter along the slot 3|, the thread then comes to lie between the wing 43 and the wall of the spindle driving head. In this position the thread is clamped fast enough so that it is automatically torn between the spindle driving head and the still ro tating full cop tube, as previously described.

After the winding, spindle has come to rest on the completion of the winding and the subsequent operation of interchanging cop tubes, the wing 43 which is then influenced merely by its own weight is in no position of rotation of the spindle driving head urged against the counter surface presented to the ring by said head with suflicient pressure for exerting the necessary clamping effect for retaining the thread between the wing 43 and the said counter surface.

In th example shown in Figs. 20 to 23, in the enlargement 21 of the spindle drivinghead 1d a

bi-partite ring

45, 46 is arranged, so that the, ring portion 45 is fixed to the spindle head 1d,- whereas the ring portion 46 is loosely inserted therein. The two

ring portions

45, 46 are formed from an initially closed ring of a diameter corthe diameter of the original ring, that is, the en-i largement 21 inside the spindle driving head 1d.- by an amount which corresponds to the radial clearance of the loose ring portion 46 withinthe enlargement 21. The two

ring portions

45, 46, are arranged in the spindle driving head id in regard to their oblique end faces in such mannerthat the fixed ring portion 45 prevents the ring portion 46 loosely inserted in the spindle driving; head 1d from dropping out of the spindle driving head in the axial direction.

When the'winding spindle providedwith the spindle driving head begins to rotate, the ring 7 portion 46 loosely inserted in the spindle drivingy head is moved from inside to outside by action of centrifugal force so that it comes to bear on the inner circumferential surface of the enlargement 21 which serves as a counter, surface'forthis portion, as shown in Fig. 21. Thereupon,

the winding thread is introduced in the slot 3|? between the ring portion 46 and the prong 32,- that is, the wall of the spindle driving head 1d,'- during the operation of interchanging cop tubes.

at the winding position, and is clamped fast between these parts. In the condition of rest of the winding spindle, the ring portion 46 is influenced merely by action of its own weight, so that it is urged against the counter surface presented to it by the spindle driving head in no position of rotation of the latter with an amount of pressure su-filcing for exerting th required clamping effect for firmly retaining the thread. The thread is finally pulled out of the spindle driving head by the completely wound cop tube being released.

Instead of a ring portion fixed to the spindle driving head, other kinds of stop means may be provided on the spindle driving head for the loose ring portion acting as a clamping element, so as to limit the movement of the last named ring portion in the radial and axial direction of the cop tube.

I claim:

1. In a thread transfer mechanism for cop winding machines having a slidable, rockable carriage, a plurality of spindles mounted in said carriage, a thread catch on each spindle, a barbed needle adjacent each spindle mounted longitudinally slidably in said carriage, a thread hook adjacent an end of each bobbin mounted on the carriage for retaining the thread during movement of a full bobbin from winding to non-winding position during a rocking movement of the carriage, and means for moving the barbed needle corresponding to a spindle having a full bobbin to transfer the thread to the catch of a spindle having an empty bobbin.

2. In a thread transfer mechanism for cop winding machines, a rockable, slidable spindle carriage, a plurality of spindles mounted in said carriage, each of said spindles having a bobbinretaining head and each having a thread catch adjacent its head, a hook on said carriage adjacent the last portion of each bobbin to be wound, a barbed needle adjacent each spindle and bobbin, means for moving said needles to transfer the thread being fed from a full bobbin, after rocking of the carriage, to the thread catch of a spindle having an empty bobbin, while the thread hook adjacent the end of the full bobbin retains the thread in line with the last end of said full bobbin to be wound during said transfer.

3. In a thread transfer mechanism for cop winding machines having a slidable, rockable carriage, a plurality of spindles mounted in said frame carriage, each spindle having a bobbinretaining head at one end, and each having a thread catch at said end, a plurality of counter bobbin holders mounted on said carriage at positions opposite the spindle heads, a guide hook adjacent each counter holder, barbed needles mounted in said carriage adjacent said spindles, a coil spring on each needle, an abutment for the ends of said needles, a stop for the ends of said needles, said needles successively cooperating with said abutment and stop according to the longitudinal and rocking ositions of the carriage, the ends of said needles engaging said abutment during winding operations and during the greater part of the rocking movements until the end of the rocking movements when the end of a needle passes out of alignment with the abutment and under the influence of the spring moving longitudinally into engagement with said stop, and during said longitudinal movement the barbed needle transferring the thread to the thread catch of a spindle having an empty bobbin.

4. In a thread transfer mechanism for cop winding machines having a slidable, rockable carriage, a plurality of spindles mounted in said carriage, a thread catch on each spindle, a clamping device on each spindle adjacent the thread catches thereof, said clamping device comprising a resilient jaw having a weight responsive to centrifugal force and an opposed clamping surface, said clamping device acting to hold the thread during rotation of the spindle and release the thread when the spindle ceases to rotate, a barbed needle adjacent each spindle mounted longitudinally slidably in said carriage, a thread hook adjacent an end of each bobbin mounted on the carriage for retaining the thread during movement of a full bobbin from winding to non-winding position during a rocking movement of the carriage, and means for moving the barbed needle corresponding to a spindle having a full bobbin to transfer the thread to the catch of a spindle having an empty bobbin.

5. In a thread transfer mechanism for cop winding machines having a slidable, rockable carriage, a plurality of spindles mounted in said carriage, a thread catch on each spindle, a clamping device on each spindle adjacent the thread catches thereof, said clamping device comp-rising a resilient leaf spring having one end secured to the spindle and having a weight mounted thereon responsive to centrifugal force and an opposed clamping surface, said clamping device acting to hold the thread during rotation ofthe spindle and release the thread when the spindle ceases to rotate, a barbed needle adjacent each spindle mounted longitudinally slid-ably in said carriage, a thread hook adjacent an end of each bobbin mounted on the carriage for retaining the thread during movement of a full bobbin from winding to non-winding position during a rocking movement of the carriage, and means for moving the barbed needle corresponding to a spindle having a full bobbin to transfer the thread to the catch of a spindle having an empty bobbin.

6. In a thread transfer mechanism for cop winding machines having a slidable,,rockable carriage, a plurality of spindles mounted in said carriage, said spindles having heads each provided with a bobbin-receiving socket and with a wide slot, a thread catch on said head adjacent said slot, a leaf spring in said socket having a weight and comprising one jaw of a clamp, a counter clamping jaw against which the spring is pressed by centrifugal force when its spindle is rotating and from which it withdraws when not rotating, a barbed needle adjacent each spindle mounted longitudinally slidably in said carriage, a thread