US3593934A

US3593934A - High speed bobbin chuck

Info

Publication number: US3593934A
Application number: US748354A
Authority: US
Inventors: Peter Conrad; Thomas E Morris; Frank W Taylor
Original assignee: Celanese Corp
Current assignee: Celanese Corp
Priority date: 1968-07-29
Filing date: 1968-07-29
Publication date: 1971-07-20
Anticipated expiration: 1988-07-20
Also published as: BR6911117D0

Abstract

A bobbin chuck for releasably gripping one or more bobbins while yarn is being wound on the bobbin. The bobbins are mounted in coaxial relation on the exterior cylindrical surface of the chuck and are held in place by a plurality of jaws which are movable outwardly to grip the interior surface of the bobbins. The jaws are spaced around the circumference of the chuck in a plurality of rows. The rows are spaced longitudinally on the chuck surface. In the interior of the chuck, a mandrel having a plurality of conical cam surfaces is spring biased axially to urge the jaws outwardly to grip the bobbins securely on the chuck. Displacement of the mandrel is controlled by a brake and release mechanism in the end of the chuck. This mechanism includes a knob and concentric ring which are exposed. By rotating the knob relative to the ring, the ring is displaced axially into engagement with a braking surface on the mandrel. Further rotation of the knob transmits an axial force through the concentric ring to the mandrel in opposition to the mandrel spring. As the mandrel is displaced by rotation of the knob, the cam surfaces move relative to the jaws, thereby allowing the jaws to be retracted by springs attached to the jaws. When the jaws are retracted, the bobbins are released. The bobbins then may be readily removed from the chuck and replaced with empty bobbins.

Description

United States Patent 172] Inventors Peter (.onrad Primary ExaminerGcorge F Mautz Charlotte; Attorneys-Leonard Horn and Stephen D Murphy Thomas E. Morris. Concord; Frank W. Taylor, Matthews, all of, NC. [2]] A L N() 748,354 ABSTRACT: A bobbin chuck for releasably gripping one or [22] Fil d J l 29, 1968 more bobbins while yarn is being wound on the bobbin The [45] Patented July 20, 1971 boboins are mounted in coaxial relation on the exterior cylin- [73] Assignec Celanese Corporation drical surface of the chuck and are held in place by a plurality New York, N.Y. of jaws which are movable outwardly to grip the interior surface of the bobbins. The jaws are spaced around the circumference of the chuck in a plurality of rows. The rows are spaced longitudinally on the chuck surface. in the interior of [54] HIGH SPEED BOBBIN CHUCK the chuck a mandrel having a plurality of conical cam sur- 9 Claims, 8 Drawing Figs faces is spring biased axially to urge the aws outwardly to grip the bobbins securely on the chuck. Displacement of the man- Cl a a t A y r y 242/465 drel is controlled by a brake and release mechanism in the end l Cl t B65h 5/3 ofthe chuck. This mechanism includes a knob and concentric Field 0[ Search it 4 ring which are exposed. By rotating the knob relative to the 46-5, 721 ring, the ring is displaced axially'into' engagement with a braking surface on the mandrel. Further rotation of the knob trans- [56] Re'erences Cited mits an axial force through the concentric ring to the mandrel UNITED STATES PATENTS in opposition to the mandrel spring. As the mandrel is dis- 2,291.863 8/l942 Baker 242/72,! placed by rotation ofthe knob, the cam surfaces move relative 2,575,776 ll/l95l White..... 242/465 to the jaws, thereby allowing the jaws to be retracted by 2,670,905 3/1954 Grauer 242/72.l springs attached to the jaws. When the jaws are retracted, the 2,941 ,745 6/1960 Perrine... 242/72.-l bobbins are released. The bobbins then may be readily 3,462,092 8/1969 Mullins 242/46.4 removed from the chuck and replaced with empty bobbins.

i 5 l I 066 676 8 6675 7 i; 76 e :5 ae 'f i 'L l/ 76 36 I8 W v f O /@9 Z2 78 78 7a 78 /06 10 26 I i 48 4 g WQ 0 aas I 1 l a ,0... ""n m5 r m k c 50 a f o w t /V e0 \gg 25 46 a m e e l 2;!

PATENTED JULZO I571 SHEET 1 OF 3 PATENTED JUL20 lsn SHEET 2 OF 3 I-IIGII SPEED BOBBIN CllIUCllf This invention relates to bobbin chucks, and more particularly to apparatus for temporarily supporting bobbins while yarn is being wound on the bobbins.

Various types of bobbin chucks have been commercially available, but these chucks suffer from the inability to operate at high winding speeds as well as from such deficiencies as inadequate or unequal grip on the bobbins, bouncing and vibrations, damaging the first layers of yarn wound on the bobbins, and clogging with yarn waste. Often these prior chucks make the replacement of bobbins on the chucks slow or awkward. These deficiencies cause the high speed winding operation to be inefficient, unsafe and uneconomical.

In view of these deficiencies in prior bobbin chucks, it is an object of this invention to provide an improved bobbin chuck that is capable of operating at winding speeds well in excess of 3,000 meters per minute.

It is a further object of this invention to provide a bobbin chuck that permits bobbins to be removed and replaced quickly and efficiently.

A still further object of this invention is to provide a bobbin chuck which tightly and safely grips the bobbin by centrifugal action to prevent displacement of the bobbin relative to the chuck during high speed winding.

Another object of this invention is to provide a bobbin chuck that is capable of accommodating a plurality of bobbins and variations in the internal diameter of the bobbins, without loss of the firm gripping engagement between the chuck and the bobbins.

A still further object of this invention is to provide a bobbin chuck that has resilient and dampened mounting of the main internal parts to eliminate vibrations of the chuck, reduce stress on the chuck bearings and tolerate out-of-balance conditions.

Another object of this invention is to provide a bobbin chuck that allows the bobbin and yarn package assemblies to align themselves so that these assemblies rotate about their center of gravity in a stable condition.

Yet another object of this invention is to provide a bobbin chuck that permits a controlled, soft starting of the rotation of the chuck and that protects the first layers of the yarn wound on the bobbins from scuffing.

A still further object of this invention is to provide a chuck that performs its multiple functions without the need for close manufacturing tolerances and that can be built simply and economically.

Still another object of this invention is to provide a bobbin chuck that is not prone to clogging with yam waste.

These objects are accomplished in accordance with a preferred embodiment of the invention by a bobbin chuck having a central shaft, a sleeve mounted for rotation on the shaft, 3 mandrel including a braking surface, with the mandrel mounted coaxially on the sleeve. Brake means are provided on the shaft adjacent the braking surface, the brake means in eluding a control ring fixed against rotation relative the shaft. The control ring has a braking surface in opposed relation to the mandrel braking surface with spring means provided to bias the control ring away from the mandrel braking surface.

A control knob is joumaled for rotation on the shaft with means between the control knob and the control ring arranged to displace the control ring braking surface into engagement with the mandrel braking surface upon rotation of the control knob in one direction, with the mandrel being axially movable relative to the sleeve.

The chuck may include rotary cam means between the control knob and the control ring, the rotary cam means arranged to displace the control ring braking surface into engagement with the mandrel braking surface upon rotation of the control knob in one direction.

The chuck may also include gripping means movable outwardly relative to the sleeve upon axial movement of the mandrel in one direction relative to the central shaft. Spring means between the-mandrel and the sleeve urging the mandrel in one axial direction are provided so that the mandrel brake surface and the control ring brake surface are arranged to displace the mandrel in the opposite axial direction upon rotation of the control knob beyond the degree of rotation required to move the mandrel and control ring brake surfaces into engagement with each other. Rotation of the knob in this one direction sequentially applies a brake, retarding rotation of the mandrel and the gripping means relative to the shaft and displaces the mandrel for retracting the gripping means to facilitate removal of the bobbins from the chuck. Empty bobbins may be posi tioned on the chuck after the filled bobbins have been doffed, and then by rotating the knob in the opposite direction, the jaws expand outwardly to lightly grip the bobbins and the brake is released. At operating speeds, under the urging of the centrifugal force, the jaws are permitted to float away from the mandrel. This action increases the grip of the jaws against the inside of the bobbins and prevents the bobbins from being thrown off the chuck at high rotational speed. Equally importantly, the bobbins and the yarn package formed on the bobbins are allowed to align themselves so that they rotate about their center of gravity in a stable manner.

Torque for the start of the rotation of the chuck is trans mitted through a driving ring that is mounted on the sleeve. The driving ring is permitted to slip relative to the sleeve when rotation of the chuck is started. When nearly operating speed is reached, pins on the sleeve are displaced outwardly by centrifugal force to lock the driving ring to the sleeve.

This preferred embodiment is illustrated in the accompanying drawings in which:

FIG. I is a perspective view of the bobbin chuck;

FIG. 2 is a cross-sectional view of the bobbin chuck, showing a portion of the chuck in elevation;

FIG. 3 is a cross-sectional view of the chuck along the line 3-3 in FIG. 2;

FIG. 4 is an enlarged crosssectional view of the drive ring assembly as in FIG. 2;

FIG. 5 is a partial cross-sectional view of the drive ring assembly along the line 5-5 in FIG. 2;

FIG. 6 is a detail radial cross-sectional view of part of the chuck drive ring assembly.

FIG. 7 is a cross-sectional view of the bobbin chuck along the line 7-7 in FIG. 2; and

FIG. 8 is a schematic view of the cam ring profile.

Referring to FIGS. I and 2, the bobbin chuck of this invention has a central shaft 2 which is adapted at one end to be mounted in a frame which holds the shaft stationary.

A sleeve II is journaled on bearing assemblies 6 and 8 for rotation relative to the shaft 2. One end of the sleeve I has a radial flange It) on which is mounted a drive assembly 12. The assembly I2 is shown in detail in FIGS. 4, 5 and 6. The ring assembly I2 is secured to the flange I0 by screws I4 (FIG. 6) which are spaced at intervals around the ring assembly I2. A ring I6 of abrasion resistant material, which may be a synthetic resin such as a polyacetal resin, is mounted in an annular groove I7 on the periphery of the ring assembly 12. The ring 16 is confined between one side of the groove I7 and the radial face of the sleeve flange I0. The width of the groove is slightly greater than the axial thickness of the ring I6, so that the ring I6 is free to rotate relative to the assembly I2 and the flange I0. An elastomeric ring 18 may be provided on the periphery of the ring I6 for transmitting torque from a bobbin drive roll (not shown) to the bobbin chuck. Of course, if the ring In is omitted, the bobbin drive roll engages the ring 16 directly.

As shown in FIGS. 4 and 5, the assembly I2 includes a centrifugal clutch for providing a driving connection between the ring I6 and the assembly 12. This clutch includes a radial countersunk bore 19 and a pin 20 that is mounted in the bore. The pin 20 is positioned in the bore I9 by an externally threaded guide M and is biased radially inwardly by a spring 22. The ring I6 has an abutment or slot 23 in position to be en- 'gaged by the pin when centrifugal force is sufficient to overcome the force of the spring 22 and to displace the pin 20 into the slot 23. Preferably, there is another slot spaced I80 degrees apart from the slot 23 and another clutch pin spaced I80 degrees apart from the pin 20.

A tubular mandrel 24 is mounted coaxially over the sleeve 4 and is fixed against rotation relative to the sleeve by a key 25 of the sleeve 4 which engages a longitudinal key slot 26 in the mandrel 24. The opposite end of the mandrel 24 is mounted on a collar 27. The collar has internal longitudinal slots 28 adjacent the sleeve 4 and radial pins 30 which are secured in the sleeve 4 and project into the slots 28 to restrict rotation of the collar 27 relative to the sleeve 4. The collar 27 has a plurality of radial arms 32, as shown in FIG. 7. The mandrel 24 has a plurality of arcuate projections 34 that are spaced symmetrically around the circumference of the mandrel and which project axially through the space between adjacent arms 32 of the collar 27. The mandrel projections 34 are connected together by a flat continuous ring 36 (FIG. 2) which is secured to the end ofeach projection 34 by screws 37 (FIG. 7).

The mandrel 24 is urged toward the right as viewed in FIG. 2 by a coil spring 38 which is mounted in a spring retainer 40. One end of the spring 38 engages a shoulder on the sleeve 4 and the opposite end of the spring 38 engages a flange in the retainer 40 to urge the retainer toward the right as viewed in FIG. 2 relative to the sleeve 4. The force of the spring 38 is transmitted to the mandrel 24 by an internal snap ring 42 secured in a circumferential groove in the mandrel. Axial movement of the collar 27 relative to the sleeve 4 is limited by a snap ring 44 adjacent the end of the sleeve 4 and a stack of washers 45 between the end of the sleeve 4'and the snap ring 44. Rubber O-rings 46 on the sleeve 4 and on the collar 27 provide a cushioned, resilient and dampened mounting for the mandrel.

On the exterior of the mandrel 24, a plurality of cylindrical spacers 48 are positioned between end sleeves 50 and 52. The end sleeve 50 is supported at one end on a circumferential shoulder 54 (FIG. 6) on the sleeve 4. The opposite end of the sleeve 50 is supported on a cylindrical surface 56 (FIG. 2) of the mandrel 24. The sleeve 50 has a plurality of axially projecting lugs 58 which are spaced uniformly around the circumference of the sleeve 50. The spacers 48, which are mounted on radial flanges 60 and cylindrical surfaces 62 on the mandrel 20, have corresponding lugs 64 at their opposite ends which abut against the edge of the adjacent spacer or against the sleeve 50, as shown in FIGS. 1 and 2. The sleeve 52 also has projecting lugs (FIG. 1) corresponding to the lugs 64 on the spacers 48. The lugs 58 and 64 on the sleeves 50 and 52 and on the spacers 48 cooperate to define rectangular openings 66, as shown in FIGS. 1, 2 and 3.

A chuck jaw element 68 is mounted in each opening 66. The elements are substantially rectangular and correspond in size and shape to the openings 66. The base of each element 68 has a conical bearing surface 70 corresponding to a conical cam surface 72 on the mandrel 24. Each element 68 has one, two or three longitudinal grooves in which are anchored resilient inserts 74. The inserts 74 project above the surface of the elements 68. The outer portion of the grooves is enlarged to provide space for the deformation of the resilient inserts. The base portion of each element 68 also has an arcuate groove along one side of the element. The Jaw elements 68 are arranged in rows around the circumference of the chuck and the grooves in the jaw elements of each row are substantially aligned. A garter spring 76 passes through these aligned grooves in a row of jaw elements to urge the elements inwardly with respect to the mandrel 24. The base portion of the elements 68 protrudes into the inside of spacers 48 so that although the elements are given some freedom to move radially with respect to the chuck, they are essentially imprisoned in the rectangular openings formed by the lugs 58 and 64.

The jaw elements 68 are held against axial movement relative to the sleeve 4 by the cylindrical spacers 48 and the sleeves 50 and 52. These spacers and sleeves are secured against rotational and axial movement relative to the sleeve 4 by dog point set screws 78 (FIG. 6) on the ring 12 which engage with the sleeve 50 and by the arms 32 of the collar 27 which engage a shoulder 80 (FIGS. 2 and 7) in a cylindrical recess in the sleeve 52.

Axial displacement of the mandrel 24 for controlling radial movement of the jaw elements 68 is effected by a brake and release mechanism at the outer end of the shaft 2. This mechanism includes a hand control knob.84 which is journaled for rotation relative to the shaft 2 on a journal bearing 86 that is rigidly secured to the end of the shaft 2. The journal bearing 86 is received in a counterbore 88 and a coil spring 90 in the counterbore 88 urges the hand knob 84 toward the left as viewed in FIG. 2 against adjustable stack of washers 89. One end of the spring 90 bears against a washer 92 that is separated from the stationary journal bearing 86 by a thrust bearing 94. The inner end of the knob 84 also has a counterbore 96. A cam ring 98 is rotationally secured to the shaft 2 by a key 100 and the cam ring projects into the counterbore 96. A cam follower 102 in the form of a circular ring bears against the cam surface on the end of the ring 98 and the follower is journaled on a screw 104 in the knob 84.

A brake plate member 106 is mounted on the shaft 2 adjacent the cam ring 98 and is restricted from rotation relative to the shaft by the key 100. The key 100 is mounted in a key slot in the shaft 2 for sliding movement relative to the shaft. A pring retainer washer 108 is mounted on the shaft 2 adjacent the brake plate 106 and a retainer washer 108 is mounted on the shaft 2 adjacent the brake plate 106 and the retainer washer 108, urges the brake plate toward the right as viewed in FIG. 2. The cam ring 98 is shown schematically in FIG. 8, wherein the peripheral surface of the ring is shown as if unwrapped and laid flat. The cam has a stop 112 indicated at the zero and 360 degrees position, which coincide. A rise 114 extends from the stop 1 12 to a dwell 116 at approximately 300. An abutment 118 on the cam ring 98 restricts further rotational movement of the follower 102 relative to the cam ring 98. The key slot in the ring 98 which engages the key 100 is shown in FIG. 8 at 120. Rotation of the hand control knob 84 relatively to the rotationally secured brake plate 106, in a clockwise direction, causes the cam follower 102 to ride up the rise 114 and push away the ring 98 against the urging of the weak spring 110, thereby displacing the brake plate into engagement with the Hat ring 36 on the end of the mandrel 24. Further rotation of the hand knob causes the axial movement of the knob to the right, as viewed on FIG. 2, against the urging of the strong spring 122. During the axial movement of the knob 84, the frictional contact of the circular frictional element 124 with the flat ring 36 generates a braking torque on the mandrel and the chuck, bobbins and yarn packages stop their rotation. When the shoulder 122 in the knob 84 abuts against the washer 92, further rotation of the knob through the action of the cam follower 102 causes the cam ring 98 to travel to the left. The leftward travel of the cam ring causes similar displacement of the brake plate 106 and the mandrel 24 also displaces toward the left in opposition of the very strong spring 38, thereby permitting the jaw elements 68 to ride down the respective cam surfaces 72 under the action of the garter springs 76. When hand control knob 84 is turned fully in a clockwise direction, the cam follower 102 rests against the abutment 118 on cam ring 98. In this position, the mandrel 24 is at its extreme left position and the outer portions of the resilient segments 74 in the jaw elements 68 lie below the outer periphery of spacers 48 and sleeves 50 and 52.

Typical bobbins 126 are shown in phantom lines in FIG. 2 as being mounted on the exterior of the spacers 48 and the sleeves 50 and 52. A single bobbin 126 is shown in FIG. 1 on the bobbin chuck. The bobbins 126 are hollow cylinders and are formed of a substantially rigid material. The internal diameter of the bobbins 126 is larger than the outerdiameter of the spacers 48 and sleeves 50 and 52, so that the bobbins may be easily applied over the end of the bobbin chuck. The axial travel of mandrel 24 is just sufficiently great to grip the internal surface of the bobbins by means of the resilient inserts 74 and compensate for irregularities in the shape of the internal surface of the bobbin and for slight dimensional variations between the several bobbins 126 that are mounted on the chuck.

In operation, the chuck is supported for rotation by mounting the shaft 2 in a conventional socket, so that the shaft is held stationary. The jaws 68 are retracted for donning bobbins by turning the knob 84! in a clockwise direction. Rotation of the knob 84 relative to the brake plate 106 causes the follower 102 to ride up the rise 114, thereby displacing the brake plate into engagement with the flat ring 36 on the end of the mandrel 24. Further rotation of the knob {M causes the jaw elements 68 to be retracted by the respective garter springs '76. The bobbins 126 may then be applied over the end of the chuck and positioned as shown in phantom lines in FllG. 2. The knob 84 is then rotated in the opposite direction. This causes the cam follower 102 to ride down the rise llil t of the cam and the spring 38 urges the mandrel 2 toward the right as viewed in FIG. 2 which urges the jaw elements db outwardly into engagement with the internal surface of the bobbins E26. The elastic elements 74 grip the internal surface of the bobbins just sufficiently to prevent slippage of the bobbins when rotation of the chuck is started. The spring i Mi urges the brake plate 1106 to separate from the flat ring 36 as rotation of the knob 84$ continues. When the friction element tld is dis placed out of engagement with the flat ring 1%, the mandrel and the sleeve 4 are free to rotate relative to the shaft 2. As the chuck gathers speed, the centrifugal force urges the jaws 6b outwards, the top section of the resilient inserts deforms fully into the enlarged portion of the longitudinal grooves and the outer surface of the jaws comes into contact with the inside of the bobbins 126. The outward travel of the jaws progresses as far as it is necessary to compensate for the enlarged inside diameter of the bobbins brought about by the centrifugal force acting on the bobbins.

Since theaxial travel of mandrel t urged by spring 1% is restricted by a stop formed by the retainer ring M and suitably selected thickness of the stack of washers 45, the outward centrifugal movement of jaws 68 causes them to float away from the mandrel. At the operating range of speed, the jaws essentially are not in contact with the surface of the mandrel and the bobbins and the yarn package are permitted to align themselves so that they rotate about their center of gravity without bounce, vibrations and excessive load on bearings, shaft and other components. Resilient rings M provide further cushioning and damping of the chuck assembly and ensure smooth, quiet operation with minimum adverse effect on the yarn.

Rotation is imparted to the chuck in a conventional manner by means of a bobbin drive roll which engages the periphery of the

rings

16 and 18 at the start of rotation of the chuck, before yarn is accumulated on the bobbins. As shown in H68. 2, d and 5, the pin 20 is normally out of engagement with the slot 23, thereby allowing slippage between the ring to and the sleeve flange 10. This slippage permits a gradual increase in speed of rotation of the chuck. When the speed of rotation reaches a sufficiently high speed, the pins move outwardly into the slots 23, so that the ring 16 is locked against rotation relative to the flange 10. When the bobbins have been filled with yarn, rotation of the chuck may be quickly braked by rotating the knob 84 to bring the braking element 124 into engagement with the rotating flat ring 36. Further rotation of the knob Ml after the chuck has stopped displaces the jaw elements inwardly to release the bobbins. The filled bobbins may then be removed over the end of the chuck.

The bobbin chuck of this invention permits bobbins to be donned and doffed quickly and easily by manipulating the control knob at the exposed end of the chuck. The brake and release mechanism applies a brake to the rotating chuck and subsequently operates the bobbin release mechanism without requiring the operator to manipulate a separate control device in the chuck. These two operations are conveniently performed in sequence merely by rotating the knob M. The float ing jaw elements, together with the resilient O-rings i6 permit the self-alignment of bobbins and packages and ensure smooth operation of the assembly at very high speeds. When two bobbins are mounted on the chuck, each bobbin and package assembly can align themselves independently and can tolerate significant out-of-balance condition. Since the jaws move only radially, there is no axial force on the bobbins during the chucking action, and therefore, no tendency to jam the bob bins against each other or against the radial face of the sleeve flange 10, thereby eliminating misalignment of the bobbins should the ends of the bobbins be not perfectly square or have projections at the extreme edges caused by damage brought about by rough handling. The OUlICT surface of the chuck (while the gripping jaws are retracted) presents an even, smooth and hard surface making the removal and putting on of bobbins easy and rapid. The travel of the jaws is substantial and the clearance between the chuck and inside of the bobbins is considerably greater than that in conventional chucks further facilitating the changing of bobbins.

The parting line between the spacers is in the form of zigzag and therefore the winding of waste into the gap between the spacers is minimized. Chuck bearings are well protected from lint, dirt and waste. Resilient rings 44 and resilient inserts 74, as well as the adjusting washers 89, together with the self-alig ning, centrifugal action of the gripping jaws compensate for the accumulation of manufacturing tolerances and ensure that these tolerances need not be excessively close to maintain the proper function of all the components, thereby substantially reducing the cost of the chuck. The driving ring assembly ensures a gradual and soft starting of the rotation of the chuck, eliminates chatter that is usually caused by out-of-round bobbins, and protects the first layers of the wound yarn from scuffing, often brought about by the chatter in conventional chucks.

While this invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein without. departing from the invention as set forth in the claims.

We claim:

it. A bobbin chuck for mounting replaceable bobbins on the external surface thereof comprising a central shaft, a sleeve mounted for rotation on said shaft, a mandrel including a braking surface, said mandrel mounted coaxially on said sleeve, brake means on said shaft adjacent said braking surface, said brake means including a control ring fixed against rotation relative to said shaft, said control ring having a braking surface in opposed relation to said mandrel braking surface, and spring means biasing said control ring away from said mandrel braking surface, a control knob journaled for rotation on said shaft, means between said control knob and said control ring arranged to displace said control ring braking surface into engagement with said mandrel braking surface upon rotation of said control knob in one direction, said mandrel being axially movable relative to said sleeve.

2. A bobbin chuck according to claim 20 including a rotary cam means between said control knob and said control ring, said rotary cam means being arranged to displace said control ring braking surface into engagement with said mandrel brak ing surface upon rotation of said control knob in one direction.

3. A bobbin chuck according to claim 2 including gripping means is movable outwardly relative to said sleeve upon axial movement of said mandrel in one direction relative to said central shaft, spring means between said mandrel and said sleeve urging said mandrel in said one axial direction, said mandrel braking surface and said control ring braking surface being arranged to displace said mandrel in the opposite axial direction upon rotation of said control knob beyond the degree of rotation required to move :said mandrel and control ring braking surfaces into engagement with each other, whereby rotation of said control knob in said one direction sequentially applies a brake retarding rotation of said mandrel and gripping means relative to said shaft and displaces said mandrel for retracting said gripping means to facilitate removal of bobbins from the chuck.

4. A bobbin chuck for mounting replaceable bobbins on the external surface thereof comprising a sleeve having a plurality of openings spaced around the circumference of said sleeve, jaw elements movably mounted in said sleeve openings, spring means'urging said elements toward the central axis of said sleeve, and means mounting said sleeve for rotation about said central axis, a mandrel having cam surfaces, said cam surfaces being arranged for urging said jaw elements radially outwardly relative to said sleeve upon axial movement of said mandrel in one direction, and means for limiting said axial movement, said cam surfaces displacing said elements outwardly in response to centrifugal force as the sleeve rotates, whereby said elements are displaced through said sleeve openings for initial engagement with a bobbin on said sleeve.

5. A bobbin chuck according to claim 4 wherein said sleeve openings cooperate with said elements to restrict said elements to radial movement.

6. A bobbin chuck comprising a central shaft, a sleeve mounted for rotation on said shaft, means on said sleeve for gripping the internal surface of a bobbin, a drive transmission ring mounted coaxially on said sleeve, said ring being mounted for rotation relative to said sleeve, and means for preventing rotating of said ring relative to said sleeve, said means operating in response to the speed of rotation of said sleeve.

7. The bobbin chuck according to claim 4 wherein said sleeve includes a peripheral groove therein, said ring being mounted in said groove, and said means for preventing rotation of the ring relative to the sleeve including a pin on said sleeve and an abutment on said ring, said pin being movable outwardly relative to said sleeve into engagement with said ring abutment, and spring means urging said pin radially inward relative to said sleeve.

3. A method of supporting bobbins for high speed winding comprising applying a bobbin on a sleeve that is mounted for rotation, said sleeve having a plurality of radially movable jaw elements mounted therein, displacing said jaw elements radially outward into initial engagement with said bobbin while said sleeve is stationary, and subsequently imparting rotation to said sleeve while allowing said elements to move radially outward in response to centrifugal force, whereby the jaw elements tightly grip the bobbins while the sleeve is rotating at high speed.

9. The method according to claim 8 wherein said imparting rotation step includes gradually starting rotation of said sleeve and increasing the speed of rotation until operating speed is reached.

Claims

1. A bobbin chuck for mounting replaceable bobbins on the external surface thereof comprising a central shaft, a sleeve mounted for rotation on said shaft, a mandrel including a braking surface, said mandrel mounted coaxially on said sleeve, brake means on said shaft adjacent said braking surface, said brake means including a control ring fixed against rotation relative to said shaft, said control ring having a braking surface in opposed relation to said mandrel braking surface, and spring means biasing said control ring away from said mandrel braking surface, a control knob journaled for rotation on said shaft, means between said control knob and said control ring arranged to displace said control ring braking surface into engagement with said mandrel braking surface upon rotation of said control knob in one direction, said mandrel being axially movable relative to said sleeve.

2. A bobbin chuck according to claim 20 including a rotary cam means between said control knob and said control ring, said rotary cam means being arranged to displace said control ring braking surface into engagement with said mandrel braking surface upon rotation of said control knob in one direction.

3. A bobbin chuck according to claim 2 including gripping means is movable outwardly relative to said sleeve upon axial movement of said mandrel in one direction relative to said central shaft, spring means between said mandrel and said sleeve urging said mandrel in said one axial direction, said mandrel braking surface and said control ring braking surface being arranged to displace said mandrel in the opposite axial direction upon rotation of said control knob beyond the degree of rotation required to move said mandrel and control ring braking surfaces into engagement with each other, whereby rotation of said control knob in said one direction sequentially applies a brake retarding rotation of said mandrel and gripping means relative to said shaft and displaces said mandrel for retracting said gripping means to facilitate removal of bobbins from the chuck.

4. A bobbin chuck for mounting replaceable bobbins on the external surface thereof comprising a sleeve having a plurality of openings spaced around the circumference of said sleeve, jaw elements movably mounted in said sleeve openings, spring means urging said elements toward the central axis of said sleeve, and means mounting said sleeve for rotation about said central axis, a mandrel having cam surfaces, said cam surfaces being arrangEd for urging said jaw elements radially outwardly relative to said sleeve upon axial movement of said mandrel in one direction, and means for limiting said axial movement, said cam surfaces displacing said elements outwardly in response to centrifugal force as the sleeve rotates, whereby said elements are displaced through said sleeve openings for initial engagement with a bobbin on said sleeve.

8. A method of supporting bobbins for high speed winding comprising applying a bobbin on a sleeve that is mounted for rotation, said sleeve having a plurality of radially movable jaw elements mounted therein, displacing said jaw elements radially outward into initial engagement with said bobbin while said sleeve is stationary, and subsequently imparting rotation to said sleeve while allowing said elements to move radially outward in response to centrifugal force, whereby the jaw elements tightly grip the bobbins while the sleeve is rotating at high speed.