DIFFERENTIAL CORE WINDING APPARATUS

Abstract

A pressurize air differential core winding apparatus comprises core mounting outer rings rotationally slidably mounted on a corresponding inner camming ring having outer camming surfaces. A rotating drive shaft has radial displaceable buttons which are displaced radially outwardly by an inner inflatable bladder to selectively rotate the inner ring forming a clutch mechanism. Each outer ring has an annular array of slots in which are elongated rotatable gripping cylindrical rollers having arcuate edges. Each roller is resiliently urged radially inwardly by an O-ring against the camming surfaces. The camming surfaces selectively urge the rollers outwardly to grip a core about which filaments are to be wound. An array of recesses in the outer ring receive a corresponding pad of fibrous members such as the hook type fasteners available as Velcro and Velcoin brands for initially frictionally engaging and gripping a received core. The fibrous members extend from a substrate having an adhesive backing for securing the pad to the recesses.

Description

This invention relates to winding apparatus drive shafts for winding tapes, cords and the like onto cores mounted on such drive shafts.

An air differential shaft comprises a mandrel for receiving cores, typically paperboard, on to which elongated members or filaments such as tapes, cords etc. are wound. Air differential shafts differs from other types of mandrels that are designed to lock a core to the mandrel to prevent rotational slip between the core and the mandrel. Rotational slip is provided between the core and the mandrel to allow the mandrel to wind multiple rolls on a single shaft at the same time. In a lock core mandrel no rotational slip is present between the drive mechanism and the core. A plurality of cores are mounted on a common shaft, each core for forming a separate roll. If all of the cores mounted on a common shaft are not the same inner diameter due to caliper variations, the smaller diameter rolls lose tension. This is undesirable as all rolls need uniform tension to uniformly wind the tapes, cords etc. onto the cores.

If the tension is too low, the elongated members may be wound too loosely. If the tension gets too high, the elongated member may break. Either condition is not acceptable on a high speed mass production apparatus.

Slip mandrels fall into two broad categories, “direct friction” or “slip ring” type. In the direct friction type, the slipping “clutch face” is between the core and the outside diameter of the mandrel. The slip ring type has a separate ring where the slipping takes place between the ring and the mandrel.

The slip ring works by stacking the cores axially in an array on a hollow tube called a body. A series of holes are bored into the body that allow pistons in the holes to protrude against an inner ring having outer ramp channels receiving balls mounted radially in the slip ring. A bladder inside the body is expanded by air pressure to force the pistons into the inner ring. The slip ring is external the inner ring and the balls protrude radially outwardly therefrom. The pistons when forced against the inner ring produce friction with the inner ring. The rotating body rotates the pistons therewith which in turn torque the inner ring rotating it. The rotating inner ring radially inclined ramp channels are intended to cause the balls to ride up the corresponding ramps. This ramping action displaces the balls radially outwardly into the hard paperboard core to grip it. This is intended to rotate the core.

However, this mechanism experiences problems. The balls initially are not sufficiently frictionally engaged with the core. When the pistons are activated not all of the balls engage their corresponding cores with uniform friction so that some cores may not rotate or rotate at different speeds than other cores. The slip rings and outer rings may rotate in unison so that the clutch action of the slip rings and balls is not activated. There must be relative rotation of the slip ring to the outer ring. The cause of this problem is that there is insufficient friction between the outer ring and core. Thus when the pistons engage and rotate the different inner rings, the outer rings will rotate with the inner rings and the clutch action does not operate. That is, when the outer ring rotates relative to the inner ring, the clutch balls ride up the ramp of the inner ring and grip the core if there is no relative rotation the ramp action does not occur and the balls do not grip the core. This results in not driving the various cores with a uniform torque, causing uneven winding on the different cores.

The problem of inconsistent slip ring tension is addressed in U.S. Pat. No. 5,451,010 which discloses friction elements that pivot outwardly to provide initial drag so that the core can be held by the piston action. This is relatively complex and costly. The friction elements protrude and do not facilitate core removal. The core needs to be rotated to remove it from the mandrel requiring additional work by an operator.

In U.S. Pat. No. 4,026,488 to Hashimoto, cylindrical winding cores are mounted on a plurality of core holders and a plurality of friction collars are mounted alternately on a single hollow shaft under axial pressure. Each of the collars is allowed to be axially moved and constrained in rotation and each of the core holders has a radial expansible means which is radially expanded by an air pressure supplied to a hollow shaft to come into pressure engagement with the inner surfaces of the cylindrical winding cores on the core holders. Catch pistons are used with a leaf spring to return the catch piston to its retracted position when pressure is lost. When pressure is applied to a pressure chamber, the leaf spring and expansible means cooperate to push the catch pistons outwardly to grip a core. The expansible means is a radially expansible elastic half tube and responsive to pneumatic pressure applied to a pressure chamber. Pressure is applied axially to couple the T-shaped collars for rotation which pressure is changed to change the magnitude of the axial pressure applied from a shaft end. This is a relatively complex and costly apparatus

In U.S. Pat. No. 2,215,069, spindles are disclosed for rolls to be wound on cores with a uniform grip. Disclosed plugs may be thrust outwardly into engagement with a core by means of a pressurized air inflatable tube encircling an inner shell and bound thereto by bands. When the tube is inflated the plugs are pressed outwardly and apply a pressure against the core inner wall to provide a compact winding and uniform tension.

U.S. Pat. No. 2,849,192 to Fairchild discloses a core engaging shaft. Fluid pressure is applied to a diaphragm to bulge it outwardly to grip a core.

U.S. Pat. No. 3,006,152 to Rusche discloses a pile driving mandrel.

U.S. Pat. No. 3,053,467 to Gidge discloses an expansible shaft employing fluid pressure. Self retractable gripping elastomeric members are mounted along an inner face of an outer shell, each with a radially extending portion. The shell is rigid and perforated with radial passages, each receiving a member radial portion. Pressure displaces the members radially outwardly in the passages and project beyond the shell to increase the overall diameter of the shell. An inner inflatable container forms an elongated chamber with the inner face of the shell. The container is inflated to displace the pistons and cause the pistons to extend from the shell.

U.S. Pat. Nos. 3,127,124, 4,220,291, 4,332,356, 4,953,877 and 6,079,662 disclose chucks and apparatus related to winding tape and similar products on cores. Many of the above patents relate generally to providing plugs which radially extend outwardly for gripping a core. While the plugs are intended to provide uniform tension on the strips, tapes and so on being wound by gripping the cores with the plugs, there is still present a problem of lack of uniform tension on the strips and so on in many instances. Such lack of uniform tension may result in breakage or loose windings as discussed above. Further, none of these patents address the slip ring problem employing ramp type inner rings coupled with pistons and balls as discussed above.

The present invention is an improvement to the core winding apparatus disclosed in commonly owned U.S. Pat. No. 6,513,751 ('751) noted above and which discloses a drive shaft having a longitudinal axis. A plurality of pistons are mounted for radial displacement in the shaft in axial arrays along the shaft axis, the axial arrays being arranged about the shaft in an annular array. A core receiving ring is mounted about the shaft, the core for receiving elongated elements to be wound thereon. The pistons selectively rotationally drive the core mounted on the core receiving ring. An inflatable bladder is radially inwardly the drive shaft and a plurality of elongated strips are included, each strip being in the interface between an axial array of the pistons and the bladder for selectively outwardly displacing the pistons to cause selective driving of a core received on the core receiving ring upon inflation of the bladder.

A clutch mechanism is associated with the pistons and the core receiving ring for selectively driving the cores mounted on the respective corresponding core receiving rings. The clutch mechanism comprises a cam arrangement responsive to the outward displacement of the pistons for the selective gripping of the core mounted on the respective core receiving ring. The cam arrangement comprises a plurality of core gripping elements radially displaceable in the core receiving ring, and a cam ring engaged with the elements and the pistons, the cam ring for selective rotation by the pistons in response to inflation of the bladder for camming the elements against the received core.

While the apparatus of '751 generally operates satisfactorily, some problems have been encountered therewith. in the '751 patent, balls 48 are radially outwardly spring loaded to exert a resilient drag force on the mounted cores. The cores when mounted over the balls 48, resiliently compress the balls radially inwardly into their associated bores providing a resilient gripping on the associated cores. The balls 48 help frictionally grip the cores to the outer rings 36 on which the cores are mounted. The problem with this arrangement is that not all of the outer rings are gripped by the balls causing a problem with the windings on the corresponding respective cores. The halls help in providing initial drag on the associated rings on which the various cores are mounted. However, not all rings are so gripped at all times.

There are also larger balls 46 that ride up outer ramp cam surfaces on the inner ring. The cam surfaces, as they rotate, urge the bails 46 radially outward to grip the cores during winding as the inner ring rotates. The rotating inner ring rotates the outer ring. A shaft commences rotation with the cores mounted on the outer ring. Rotation of the shaft rotates associated pistons therewith. An innermost bladder is inflated to urge the pistons radially outwardly to frictionally engage the inner ring (having the outer ramp cam surfaces). These balls provide the major drive force for the cores. These balls however tend to deform the cores forming an annular groove in the core inner surface due to localized pressure by the balls on the cores. This groove results in undesirable slippage of the core during winding.

A prior problem is that the inner ring, without the smaller spring loaded balls 48, did not always move sufficiently relative to the outer ring and to the balls 46 to cause the larger balls 46 to sufficient grip the corresponding core because of the low friction between the outer ring member and the corresponding core. The smaller resilient balls 48 helped to alleviate this problem. In addition, the smaller balls reduced the friction between the cores and the outer ring 36 that might be present to facilitate removal of the cores after winding.

However, these smaller resiliently loaded balls 48 still exhibit a problem with uniform gripping of all of the corresponding mounted cores and without these smaller balls, the removal of the cores is difficult due to the presence of the larger balls 46. The present invention is a recognition of the problems with the prior '751 patent system and is directed to resolve these problems.

A core winding apparatus according to an embodiment of the present invention and wherein the core is for receiving elongated elements to be wound thereon, comprises a drive shaft having a longitudinal axis about which the shaft rotates. An outer core receiving ring is mounted about the shaft. A plurality of elongated circular cylindrical rollers are mounted on the core receiving ring, each roller being resiliently urged radially inwardly and arranged for selective radial outward displacement relative to the ring for selective gripping of a core received on the ring. An inner cam ring is rotatably mounted between the shaft and the outer core receiving ring, the cam ring having a plurality of outer cam surfaces, each surface for camming engagement with a different corresponding roller of the plurality of rollers for the selective radial outward displacement of that roller. A clutch mechanism is associated with the shaft for selectively rotationally coupling the inner cam ring and outer ring to the drive shaft for selective rotation of the cam ring and outer ring.

In a further embodiment, each of the rollers rotates about a first axis parallel to the shaft axis, each roller having a first arcuate longitudinally extending outer surface that encircles the first axis, the outer surface having a second arcuate surface that terminates at opposite end edges of the rollers, the second arcuate surface being defined by a second axis that is normal to the first axis.

In a still further embodiment, each roller has an annular groove, and an O-ring in the groove for resiliently urging the corresponding roller radially inwardly toward and into engagement with a cam ring cam surface.

In a further embodiment, a plurality of fibrous members are attached to the core receiving ring in selected surface regions of the outer ring for frictionally engaging and securing a received core to the core receiving ring.

The plurality of fibers in another embodiment extend upwardly from the core receiving ring for frictionally engaging and securing a received core to the core receiving ring.

In a further embodiment, the core receiving ring has an outer surface and a plurality of recesses in the outer surface, and the apparatus further includes a pad of radially outwardly extending fibers attached in each recess.

In a still further embodiment, each recess is spaced intermediate an adjacent pair of spaced rollers in the core receiving ring. Preferably, the rollers are spaced at opposing locations on the core receiving ring about 180° apart in a plane.

In a further embodiment, a core winding apparatus comprises a drive shaft having a longitudinal axis about which the shaft rotates and a core receiving ring mounted about the shaft. A plurality of rotatable members are mounted on the core receiving ring and arranged for selective radial outward displacement relative to the ring for selective gripping of a core received on the ring. A rotatable cam ring is mounted between the shaft and the core receiving ring, the cam ring being mounted radially outwardly of the drive shaft and having a plurality of cam surfaces, each cam surface for camming engagement with a different corresponding rotatable member of said plurality of rollers for said selective radial outward displacement. A clutch mechanism is associated with the shaft for selectively rotationally coupling the cam ring to the drive shaft for selective rotation of the cam ring and outer ring by the drive shaft. A plurality of fibrous members are attached to the core receiving ring in at least one given outer surface region for frictionally engaging and securing a received core to the core receiving ring.

IN THE DRAWING

FIG. 1 is a sectional side elevation view through a core winding apparatus according to an embodiment of the present invention;

FIG. 2 is a sectional front elevation view through the apparatus of FIG. 1;

FIG. 3 is a side elevation sectional view of the drive shaft of FIG. 4 taken along lines 3-3;

FIG. 4 is a front elevation view of the drive shaft;

FIG. 5 is a side elevation view of the drive shaft of FIG. 4;

FIG. 6 is a sectional elevation view of the drive shaft of FIG. 5 taken along lines 6-6;

FIG. 7 is a side elevation view of a representative button used in the clutch mechanism of the embodiment of FIG. 1;

FIG. 8 is an end sectional elevation view of the outer ring and inner camming ring assembly of the embodiment of FIG. 1 showing the rollers in a radially inward core disengaged position;

FIG. 9 is a sectional elevation view of the assembly of FIG. 8 taken at lines 9-9;

FIG. 10 is an end elevation sectional view of the outer ring and inner camming ring assembly of the embodiment of FIG. 1 showing the rollers in a radially outward core engaged position.

FIG. 11 is a sectional elevation view of the assembly of FIG. 10 taken at lines 11-11;

FIG. 12 is an end elevation view of the outer ring of FIGS. 8 and 10 without the rollers;

FIG. 13 is a side elevation view of the outer ring of FIG. 12 showing the bore for a roller and recesses for the fibrous members;

FIG. 14 is an end elevation view of the camming ring of FIGS. 8 and 10;

FIG. 15 is a side elevation view of the inner camming ring of FIG. 14;

FIG. 16 is a is a side elevation view of the outer ring showing the roller installed and retained by an O-ring and the fibrous members attached;

FIG. 17 is a more detailed elevation sectional view of the mounted fibrous member taken at lines 17-17 of FIG. 16;

FIG. 18 is an end elevation view of a representative roller of FIG. 1;

FIG. 19 is a side elevation view of a representative roller of the embodiment of FIG. 1 without the pins for securing the roller to the outer ring; and

FIGS. 20 and 21 are isometric views of a spring pin for movably securing the rollers to the outer ring for radial displacement.

In FIG. 1, assembly 10 in the present embodiment comprises an elongated steel circular cylindrical stem 12. Mounted about the stem 12 is an elongated inflatable rubber, elastomeric or other inflatable sheet material bladder 14 which is elongate and cylindrical. The bladder 14 is selectively inflated by pressurized air from a source (not shown) via inlet 16 in the stem 12. The bladder 14 and stem 12 are mounted within the axially extending bore 18 of drive shaft 20. The bladder and stem may be conventional.

Mounted on the periphery of the bladder 14 is an annular array of parallel like elongated spaced apart force distribution metal strips 60.

The drive shaft 20, FIG. 3, is preferably steel and has a plurality of like radial stepped through bores 22. The bores 22 comprise a plurality of sets of four coplanar bores in each set. For example, in FIG. 6, the four bores 22′ are coplanar with two bores coaxial and at right angles to the other coaxial two bores of the set. The bores of adjacent sets are oriented at 45° relative to the next adjacent set. That is, the bores of each set having longitudinal bore axes at 45° angles to each other relative to the shaft axis 23. For example, in FIG. 3, the longitudinal axes of the bores 22″ lying on plane 1 are at 45° to the axes of the bores 22′″ on plane 2 relative to the shaft axis 23.

In FIG. 1, a plastic T-shaped button 24, which may be Delrin AF in one embodiment, is in each bore 22. Button 24, FIG. 7, has a circular cylinder shank 24′ and a somewhat larger diameter head 24″. The head sits in an enlarged step portion 25, FIG. 3, of the bore 22, all bores 22 being identical. This stepped bore and head arrangement of the bores and mating buttons prevents the buttons 24 from dropping out of their bores 22 in the shaft 20. The button head 24″ extends beyond the bore step portion 25 abutting the bladder 14. The button 24 is radially outwardly displaced in its respective bore 22 when the bladder is inflated. The inflated bladder displaces the buttons radially outwardly so that the buttons protrude beyond the shaft 20. Normally the buttons 24 are recessed within the shaft 20 at the button radially outward surface as seen in FIG. 1. The shank of the button at this time protrudes through the bottom of the bore 22 as shown in FIG. 1. The number and size of the buttons can be tailored for the particular desired torque characteristics for each implementation.

The buttons 24 when radially inwardly displaced as in FIG. 1 abut an aligned force distribution strip 60. When the bladder 14 is expanded it pushes the strips 60 radially outwardly and thus forces the buttons 24 radially outwardly. The force distribution strips 60 allow more of the distributed forces from the bladder to be concentrated on the bottom surface of the buttons than otherwise would be normally possible with just a bladder-button direct interface. The force distribution strips also prevent the bladder, which is of soft material, from being damaged when placed in repetitive contact with the drive shaft bores that are at the drive shaft bore. The array of strips 60 are bound together by a ring of electrical tape (not shown).

In FIG. 2, an inner ring 26, which is preferably bronze, but may be other materials such as molded thermoplastic, e.g., phenolic and so on, surrounds the shaft 20 and overlies buttons 24. In FIGS. 8-11, and 14-15, the inner ring 26 has a circular cylindrical outer surface 28. Four like grooves 30 are formed in the surface 28. Each pair of adjacent grooves 30 terminates at a radially outwardly extending ridge 32 coextensive with outer surface 28. The grooves 30 are each partially circular cylindrical between the ridges 32 and then each slope gradually radially and circumferentially outwardly toward and terminating at a corresponding ridge 32 in two opposing directions relative to the central axis of the ring 26. The grooves 30 and ridges 32 form a camming surface on the outer peripheral surface of the inner ring 26. The inner ring surface 34 is circular cylindrical. Surface 34 is a bearing surface against which tile buttons 24 abut when they are displaced radially outwardly. There is slippage between surface 34 and the buttons 24 which slippage controls the winding tension in response to the bladder 14 pressure. As the bladder pressure increases, the torque between surface 34 and the buttons 24 increases providing more drag on the inner ring 26, and, thus changing the tension on the wound strips during winding.

In FIGS. 2 and 8-13, outer ring 36 is preferably aluminum and has circular cylindrical inner surface 38 and a circular cylindrical outer surface 40. A plurality (four in this case) of like radial slots 42 are equally spaced about the ring at a right angle to the next adjacent slot. The slots 42, FIG. 13 are elongated and generally oval with semi-circular cylindrical end surfaces as shown. The slots 42, FIG. 12, extend through the outer ring 36 in communication with the outer surface 40 and inner surface 38. A pair of aligned transverse bores 41, FIGS. 12 and 13, pass through the side of the ring 36 into communication with each of the slots 42 about medially the outer surface 40 and inner surface 38.

The slots 42 correspond in number and spacing to the ramp surfaces 30 or ridges 32 in the inner ring 26, FIGS. 8 and 10. As a result, each slot 42 is aligned simultaneously over a corresponding like position of the surfaces 30 or ridge 32 when the outer ring member 36 mounted over the inner ring member 26 as shown in FIGS. 2, 8 and 10. Thus in one relative angular position, the slots 42 are aligned over the ridges 32 and in other angular positions are aligned over the same portion of the corresponding grooves 30 as best seen in FIGS. 8 and 10. The outer ring also has an annular groove 37, FIG. 13. This groove receives an O-ring 39 as best seen in FIG. 16.

A roller 46, FIGS. 1, 2, 8-11 and 16, mates with and is located in each of the slots 42. The rollers 46 have a length dimension that is slightly smaller than the slot inner transverse dimensions so that the rollers can freely displace in the respective slots 42. In FIGS. 18 and 19, representative roller 46 comprises a circular cylindrical portion 47. An annular groove 49 circumscribes the portion 47 centrally thereof. Two axially extending aligned bores 51 are located in each end portion of the roller 46. The bores 51are aligned on axis 53. The roller 46 also has opposite end surfaces 55 which are arcuate. The end surfaces 55 curve about respective axes 57 which are normal to axis 53.

The rollers 46 are retained in the slots 42 by spring pins 43 which are frictionally held in bores 41, FIG. 13. Spring pin 43, FIG. 20, is commercially available. It comprises a tube 45 with a longitudinal slot 59. The pin 43 is larger in diameter than the diameter of the bores 41 so that compression against the bore 41 wall holds the pin in place in the bore 41. The pin 43 engages the roller bore 51 to retain the roller 46 in the outer ring slot 42. The pin 43 is smaller in diameter than the diameter of the bore 51 of the roller 46. This relationship permits the roller to displace radially inwardly and outwardly in the slot 42. In the alternative, a coiled spring pin 61, FIG. 21, can be used to hold the roller 46 in the slot 42. The coiled spring is spiraled spring metal which flexes after insertion into a mating bore and can accommodate wide tolerances in the mating bore.

The O-ring 39, FIGS. 9, 11, and 16 resiliently urges the roller 46 radially inwardly toward and against the inner camming ring 26 camming surfaces of grooves 30. The rollers 46 thus abut and roll over the camming surfaces including the ridges 32 of the inner ring as shown in FIGS. 8-11 according to the relative position of the camming surfaces to the rollers. As shown in FIGS. 10 and 11, the rollers can protrude from the slots to engage a mounted core (not shown), but can not freely leave the slots due to their being captured to the slots by the pins 43.

The outer ring 36, FIG. 13, has a pair of like generally oval recesses 50 in the ring outer surface 40 on opposite sides of the groove 37. There are a pair of like recesses on the diametrically opposite side of the ring 36. In FIG. 17, a pad 52 of fibers 54 is mounted in the recess and adhesively attached, i.e., glued or bonded, to the ring 36 outer surface inside the recess 50 with a bonding agent 56. The fibers are supported on a substrate 58. In this embodiment, the pad 52 of fibers are commercially available fibrous flexible thermo plastic molded hooks as available as hook and loop fasteners and known as Velcro or Velcoin brand fasteners. These comprise fibers extending from a substrate and typically the substrate has an adhesive backing to secure the substrate to another element. The fibers are in an array and readily resiliently bend when compressed under load providing a friction load on the element that compresses the fibers. However, the pad 52 comprises only the array of the flexible plastic hook portions of this fastener arrangement. The substrate with the hook type fibers is supplied commercially with an adhesive backing to bond the substrate to a surface.

The type of fibrous hooks used, i.e., the flexibility and stiffness of the fibers, their thickness or diameters, their materials, and so on, is determined according to a given implementation for frictionally gripping the mating core (not shown) to be received on the outer ring 36 at a desired friction load. This load may also be determined by the total area subtended by the array of fibers as well as the number and spacing of the pads. In the present implementation there are two opposite pairs of pads of fibers to provide a diametrical symmetrical load on the mounted core. A pair of pads are on diametrically opposite sides of the outer ring.

In one implementation, the pad of fibers may comprise a circular disc of fibers that is about ⅜ inches (about 1 cm) in diameter. The recesses 50 are complementary in shape, FIG. 17. In the alternative, the recess 50 side walls may not be exactly complementary shaped as the pads 52 in that the sides of the recesses could be sloped. This is acceptable.

The fibers 54 protrude above the plane of the outer ring outer surface an amount sufficient to frictionally grip the received core to be wound, e.g., about 1 mm. The fibers while flexible, are relatively stiff to provide the desired friction load on the mounted core. The outer ring 36 closely receives such cores on which elongated elements such as cord, tape and the like are to be wound. The cores are typically paperboard as known in this industry. The cores, without the fibrous pads, otherwise would be mounted relatively loosely on the outer ring while the rollers remain recessed in their respective slats.

The rollers 46 ride in the grooves 30 of the inner ring 26. In FIG. 8, the rollers 46 are aligned over the midsection of the grooves 30 and thus are urged into the groove 30 at the top of the inner ring 26 by the O-ring 39, FIGS. 1, 9 and 11. All of the fibers 54, FIG. 17, are normally protruding above the outer surface of the outer ring as shown and thus also grip a mounted core (not shown), typically made of relatively hard paperboard.

In operation, cores (not shown) for receiving tape strips, paper strips, cord or other elongated elements to be wound about the cores are mounted on the outer mounting ring members 36. The cores may be narrower or wider than the ring members 36, but may be of the same width in the axial direction of axis 52, FIG. 1. The cores are dimensioned to slide over and about the rings 36 along the shaft axis 52. For example, there may be about a 0.030 inch clearance between the cores and the outer surface of the outer mounting ring 36. In so mounting the cores, the cores correspond to one or more rings 36 or portions thereof and are concentrically mounted thereon. The rollers and fibrous friction pads are spaced along and about the shaft to accommodate cores of differing axial widths. The cores are mounted on the outer rings before air pressure is applied to the bladder 14.

A core comes into contact with a roller 46 that might be protruding above the ring 36 outer surface as the core is axially displaced over the ring outer surface. Preferably, the rollers are aligned with the inner ring grooves such the rollers are initially recessed and thus may nut contact the core as it is being mounted. The end radius on each end of a roller 46, depending upon which roller end is contacted by a core during axial installation of the core over the outer ring outer surface, will cause the roller 46 to be pushed or retained radially inwardly and guided, as applicable, with the aid of the O-ring 39, FIGS. 9 and 11, upon proper alignment of the inner cam ring grooves. This action causes the rollers to be displaced into a position between the outer surface of the outer ring 36 and the ramp cam surfaces of the grooves 30, FIGS. 8 and 10.

The combination of the O-ring and the roller radius 55 at its edges (FIG. 19) helps alleviate a problem of “bumpiness” attributed to the loading and unloading of cores in other winding apparatuses. The O-ring encircles the outer ring 36 in its groove 37, FIG. 13, while capturing the rollers 46 to the outer ring as best seen in FIG. 19. The number of cores and their axial location along the apparatus 10 will vary according to a given implementation. In one embodiment, the rollers are molded thermoplastic material.

Once the core(s) is/are placed at the required location(s), pressurized air is fed into the stem 12, FIG. 1 via the air inlet 16. This expands the bladder and forces the force distribution strips 60 radially outward. This action pushes the buttons 24 into contact with the inner surface of the inner ring 26.

When the drive shaft 20 begins to rotate after the pressurized air is applied, FIG. 1, the resulting forces cause the drive shaft, stem, bladder, force distribution strips 60, buttons 24, and inner ring 26 to rotate in unison. With a core (not shown) mounted on the outer ring 36, the resulting contact between the fibers 54 of the fibrous pads 52 provides an initial friction force between the outer ring 36 and the mounted core. This friction force, along with added initial tension of the attached material to be wound, causes the outer ring, along with the attached components consisting of the rollers, fibers, to momentarily remain stationary while the remaining components rotate. During this brief interval, with the inner ring 26 rotating relative to the outer ring, the camming grooves 30 begin to push the rollers radially outwardly in their slots 42 forming a clutch which engages the inside diameter surface of the mating core. Once this occurs, the entire arrangement of the shaft to the outer ring begins to rotate in unison and the filamentary material begins to be wound about its core.

The cores may be the same width or greater than the outer ring 36 in the axial direction. The elongated rollers 46 minimize the problem with the earlier prior art arrangements using balls which could wear a groove inside the core surface causing slippage of the core. The circular cylindrical elongated nature of the rollers 46 minimizes this problem and results in a greater gripping force due to the increased surface area of the roller that engages the core surface. Since the roller is symmetrical, it allows for winding in to be bidirectional.

During winding the tension on the wound strips or filaments can be varied as needed. As the air pressure within the bladder decreases, the force exerted on the buttons 24 against the inner ring 26 decreases, thus allowing increased slippage to occur between the surfaces, resulting in decreased tension in the wound roll. An increase in air pressure results in an increase of tension in the wound roll.

The present embodiments thus recognize that the additional needed friction is provided initially by relatively softer, but stiff, fibrous elements which do not have a tendency to damage the core surface or permit slippage. The fibers insure that the outer ring will rotate the core by way of its friction grip to the initially stationary core (the core tends to stay stationary via the tension on the cord, tape etc. attached to the core) and not slip relative to the core at the beginning of the cycle. Thus without the fibers, there might be slippage of the core to the outer ring member and the clutch action of the rollers will not commence. Thus, in this case, the inner ring member may never force the rollers to fully grip the core in some cases.

The fibers, however, always induce a friction load between the core and outer ring member to over come the tension force on the elongated members to be wound about the core. Thus, when the inner ring is rotated by the rotating buttons, the friction with the core induced by the fibers is such that the core will initially rotate with the inner ring member. This action causes the rollers to move up the respective ramps and clutch engage the core, firmly gripping the core.

The fibers in a stationary mode always press against the core to be wound. After winding, these fibers provide a bearing surface for the core mounted thereon so the core can easily be removed from the outer ring. The rollers become recessed into their slots and this may result in friction engagement of the core to the outer ring in the absence of the fibers. This friction interferes with the removal of the cores from the outer rings. The fibers thus reduce the friction between the core and outer ring that might otherwise be present after the rollers are recessed.

As is evident, the inner ring with the sloping surfaces forms a clutch mechanism with the rollers 46 and buttons 24. The clutch exhibits slippage between the drive shaft and the gripping of the received core by the gripping rollers in accordance with the principles described above. Inflation of the bladder controls the forces on the buttons and thus the friction engagement load of the buttons on the inner ring and thus the drive torque on the received core.

It will occur to one of ordinary skill in this art that various modifications may be made to the disclosed embodiment without departing from the spirit and scope of the invention. For example, while Velcro and Velcoin type hook fibers are used in the disclosed embodiment, it will occur to one of ordinary skill that other fibrous material may be used according to a given implementation. Such fibrous material may be cloths that exhibit fibrous naps such as cotton, polyester, acrylic, wool and other fabrics whether woven, knitted, matted as in felt, fleece, natural or synthetic fur, or otherwise. The required stiffness to obtain the desired friction may be obtained by compacting relatively less stiff fibers more tightly together or by making softer less stiff fibers shorter than the Velcro fibers. The disclosed embodiments are for illustration and not limitation. The invention is defined by the appended claims.

Claims

1. A core winding apparatus, the core for receiving elongated elements to be wound thereon, the apparatus comprising: a drive shaft having a longitudinal axis about which the shaft rotates;an outer core receiving ring mounted about the shaft;a plurality of elongated circular cylindrical rollers mounted on the core receiving ring, each roller being resiliently urged radially inwardly and arranged for selective radial outward displacement relative to the ring for selective gripping of a core received on the ring;an inner cam ring rotatably mounted between the shaft and the outer core receiving ring, the cam ring having a plurality of outer cam surfaces, each surface for camming engagement with a different corresponding roller of said plurality of rollers for the selective radial outward displacement of that roller; anda clutch mechanism associated with the shaft for selectively rotationally coupling the inner cam ring and outer ring to the drive shaft for selective rotation of the cam ring and outer ring.

2. The apparatus of claim 1 wherein each said rollers rotate about a first axis parallel to the shaft axis, each roller having a first arcuate longitudinally extending outer surface that encircles the first axis, the outer surface having a second arcuate surface that terminates at opposite end edges of the rollers, the second arcuate surface being defined by a second axis that is normal to the first axis.

3. The apparatus of claim 1 wherein each said rollers has an annular groove, and an O-ring in the groove for resiliently urging the corresponding roller radially inwardly toward and into engagement with a cam ring cam surface.

4. The apparatus of claim 1 further including a plurality of fibrous members attached to selected outer surface regions of the core receiving ring for initially frictionally engaging and securing a received core to the core receiving ring.

5. The apparatus of claim 1 further including a plurality of fibers extending upwardly from the core receiving ring for initially frictionally engaging and securing a received core to the core receiving ring as the core is being received on the core receiving ring.

6. The apparatus of claim 1 wherein the outer core receiving ring has an outer surface and a plurality of recesses in the outer surface, and further including a pad of radially outwardly extending fibers attached to the core receiving ring in a corresponding one of each said recesses.

7. The apparatus of claim 6 wherein each recess is spaced intermediate an adjacent pair of rollers in the core receiving ring.

8. The apparatus of claim 1 wherein the rollers are spaced at opposing locations on the core receiving ring about 180° apart in a plane.

9. The apparatus of claim 1 further including a plurality of fibrous members attached to the core receiving ring for initially frictionally engaging and securing a received core to the core receiving ring and spaced at opposing locations on the core receiving ring about 180° apart in a plane.

10. A core winding apparatus, the core for receiving elongated elements to be wound thereon, the apparatus comprising: a drive shaft having a longitudinal axis about which the shaft rotates;a core receiving ring mounted about the shaft;a plurality of rotatable members mounted on the core receiving ring and arranged for selective radial outward and inward displacement relative to the ring for selective gripping of a core received on the ring;a rotatable inner cam ring mounted between the shaft and the core receiving ring, the cam ring being mounted radially outwardly of the drive shaft and having a plurality of cam surfaces, each cam surface for camming engagement with a different corresponding rotatable member of said plurality of rotatable members for said selective radial outward displacement;a clutch mechanism associated with the shaft for selectively rotationally coupling the cam ring to the drive shaft for selective rotation of the cam ring and outer ring; anda plurality of fibrous members attached to the core receiving ring in at least one given outer surface region of the core receiving ring for initially frictionally engaging and securing a received core to the core receiving ring.

11. The apparatus of claim 10 wherein the fibrous members comprise an array of a plurality of fibrous hook members upstanding from the core receiving ring in a given region, each hook member comprising at least one fiber.

12. The apparatus of claim 10 wherein the rotatable members are elongated rollers.

13. The apparatus of claim 10 wherein the rotatable members are elongated rollers, each roller having a groove, and an O-ring in the groove for resiliently urging the roller radially inwardly toward and in engagement with an inner cam ring cam surface.

14. The apparatus of claim 10 wherein the rotatable members are elongated rollers each for rotation about a further axis parallel to the shaft longitudinal axis, the rollers having opposing edges in a direction along the further axis, the rollers opposing edges being arcuate and extending about an axis normal to the further axis.

15. The apparatus of claim 10 wherein the fibrous members comprise pads with a radially upwardly extending flexible fiber pile relative to the shaft longitudinal axis and secured to the outer core receiving ring.

16. A core winding apparatus, the core for receiving elongated elements to be wound thereon, the apparatus comprising: a drive shaft having a longitudinal axis;a plurality of buttons mounted for radial displacement in the shaft in axial arrays along the shaft axis, the axial arrays being arranged about the shaft in an annular array;an outer core receiving ring rotatably mounted about the shaft;an inflatable bladder radially inwardly the drive shaft;a plurality of elongated strips, each strip being in the interface between an axial array of the buttons and the bladder for selectively outwardly displacing the buttons;a rotatable inner cam ring having a plurality of outer periphery cam surfaces, the cam ring being responsive to the radially outward displacement of the buttons for selective rotational movement in response to rotational movement of the drive shaft and the radial engagement of the buttons with the cam ring;a plurality of elongated cylindrical rollers associated with the cam ring and arranged for radially displacement in corresponding bores in the core receiving ring, the cam ring for selectively radially outwardly displacing the plurality of rollers for selective frictional engagement with a corresponding received core, the rollers for rotationally driving the core in response to rotation of the shaft; anda plurality of fibrous members attached to the core receiving ring in at least one given outer surface pile region for frictionally engaging and securing a received core to the core receiving ring.

17. The apparatus of claim 16 wherein the rollers each have an annular groove, further including an O-ring mounted in the groove for resiliently urging the corresponding roller radially inwardly engaged with the cam ring.

18. The apparatus of claim 16 wherein the rollers have arcuate outer surfaces facing in two orthogonal directions.

19. The apparatus of claim 16 including a pressurized air input port for inflating the bladder.

20. The apparatus of claim 16 wherein the rollers and fibrous members alternate with respect to each other in a direction along the longitudinal axis, the fibrous members being located at about 180° apart about the core receiving ring.