US3390552A - Apparatus for feeding elastic yarn - Google Patents

Description

July 2, 1968 N. T. KING APPARATUS FOR FEEDING ELASTIC YARN 5 Sheets-Sheet 1 Filed Sept. 13. 196i INVENTOR NOBLE T. KING ATTORNEY July 2, 1968 N. T. KING 3,390,552

APPARATUS FOR FEEDING ELASTIC YARN Filed Sept. 13. 196 5 Sheets-Sheet 2 INVENTOR. NOBLE T. KING July 2. 1968 N. T. KING APPARATUS FOR FEEDING ELASTIC YARN 3 Sheets-Sheet 5 Filed Sept. 15, 196?.

89 INVENTOR.

NOBLET. KING ATTORNEY 3,390,552 APPARATUS FOR FEEDING ELASTIC YARN Noble T. King, Decatur, Ala, assignor to Monsanto Company, St. Louis, Mo., a corporation of Delaware Filed Sept. 13, 1965, Ser. No. 486,892 Claims. (Cl. 66-132) ABSTRACT OF THE DISCLOSURE An apparatus for feeding an elastic yarn to a hosiery knitting machine at variable rates wherein the yarn is fed at a constant maximum rate during the knitting of the upper calf portion of the stocking, is fed at a uniformly decreasing rate during the knitting of the lower calf portion of the stocking and is fed at a constant minimum speed during. the knitting of the ankle and foot portion of the stocking.

This invention relates to apparatus for feeding elastic yarn and more particularly to apparatus for feeding a spandex yarn to a hosiery knitting machine.

The use of rubber filaments in making elastic and support fabrics has been known for some time. A more recent development is the use of spandex yarns in making stretch and support fabrics. The advantage of spandex over rubber is that the spandex is not subject to deterioration caused by light and perspiration and can be used in smaller denier than can rubber filaments. Spandex has been used recently in making support stockings but because of difficulties in feeding the spandex into the hosiery machine, it has been necessary to use a large denier and a complicated stitch. This has resulted in a heavier and more expensive stocking with the usual undesirable support stocking appearance. With this in mind, one of the objects of this invention is to provide a novel and improved device for feeding an elastic yarn.

Another object of this invention is to provide a device for feeding a small denier elastic filament to a hosiery knitting machine.

Another object of this invention is to provide a device for feeding a spandex filament to a hosiery knitting machine under constant tension and at a rate which varies with the circumference of the stocking.

Still another object of this invention is to provide an apparatus for feeding a spandex yarn to a hosiery machine in such a manner that the machine is rendered capable of knitting a support stocking which does not have the undesirable appearance of ordinary support stockings.

A further object of this invention is to provide a device for feeding a spandex filament to a hosiery knitting machine in such a manner that the yarn is fed under constant tension throughout the length of the stocking and at a varying speed during the knitting of the lower calf portion of the stocking.

One embodiment of the present invention contemplates a device adapted to be attached to and driven by a seamless hosiery machine. The device positively drives a bobbin of spandex yarn to feed the spandex yarn to the hosiery machine at a constant maximum speed during the knitting of the upper calf portion of the stocking. During the knitting of the lower calf portion of the stocking the bobbin is driven at a steadily decreasing rate to compensate for the steadily decreasing circumference of this portion of the stocking. During the knitting of the ankle and foot portion of the stocking the device drives the bobbin to feed the spandex yarn to the hosiery machine at a constant minimum speed. Thus, the amount of spandex yarn fed to the machine ice is roughly proportional to the circumference of the stocking at all points thereon when the stocking is worn.

In greater detail, the device of the present invention; includes a drive wheel which is driven by the hosiery machine and which is positioned to engage and drive a disc attached to a spandex bobbin holder. A sensing Wheel in contact with a package of spandex yarn 011 the bobbin holder radially adjusts the position of the drive wheel on the disc so that the spandex yarn is fed from the package at a constant speed. During the knitting of the upper calf portion of the stocking the drive wheel is at a maximum radial position relative to the sensing wheel so that the yarn package is driven at a maximum speed. During the knitting of the lower calf portion of the stocking the drive wheel is steadily moved radially inward relative to the sensing wheel so that the spandex yarn is fed to the machine at a steadily decreasing rate. During the knitting of the ankle and foot portion of the stocking the drive Wheel is at a minimum radial position relative to the sensing wheel so that the spandex yarn is fed to the hosiery machine at a minimum speed.

Gther objects and advantages of the invention will become apparent when the following detailed description is read in conjunction with the appended drawing in which FIGURE 1 is a perspective view of the device of the present invention showing the general relationship of the elements thereof;

Fl-GURE 2 is an elevational view of the back of the device;

FIGURE 3 is an enlarged, exploded perspective view of the structure which supports a bobbin driving wheel; and

FIGURE 4 is a diagrammatic side view of a stocking showing the various parts thereof.

Referring now in detail to the drawings, there is shown a support bracket 11 which is secured in any desirable manner to a machine for knitting seamless stockings, a portion of which machine is indicated by reference numeral 12. Inasmuch as the construction and operation of this type of hosiery machine is well known in the art, this machine will not be described in detail. The upper end of the bracket 11 supports a yoke 13 having therein bearings 14 which rotatably support a shaft 17 carrying a bobbin holder 18. The bobbin holder 18 supports a package 19 of spandex yarn, the yarn 20 being withdrawn from the package 19 and fed to the hosiery knitting machine. The end of the bobbin" holder 18 has secured thereto a disc 22 which is driven to rotate the yarn package 19.

Spandex fiber is a fiber in which the fiber forming substance is any long chain synthetic polymer composed of at least percent by weight of a segmented polyurethane. Spandex yarns and methods of making them are well known.

The yarn package 19 is driven by a drive wheel 23 having around the periphery thereof a rubber ring 24 which is adapted to engage the face of the disc 22 to rotate the bobbin holder 18 and the yarn package 19. The drive Wheel 23 is secured to a shaft 27 rotatably mounted in a yoke 28 which is movably mounted on the bracket 11. The shaft 27 and the drive wheel 23 are driven by and in timed relationship with the hosiery knitting machine. This is accomplished by connecting the shaft 27 to the back gear 30 (FIGURE 1) of the hosiery machine. A bracket 31 mounted on the hosiery machine rotatably supports a shaft 32 which has a beveled gear 33 on one end and a spur gear 36 on the other, the spur gear 36 being meshed with the back gear 30. The beveled gear 33 is meshed with another beveled gear 37 secured to a shaft 38 rotatably mounted in the bracket 31. The shaft 38 is connected to the shaft 27 through a pair of universal joints 39 and a telescoping connector 40. The purpose of the telescoping connector 40 is to allow upward and downward movement of the drive wheel 23 along a radius of the disc 22 to thereby change the speed at which the yarn package 19 is driven.

Since the drive wheel 23 is driven constantly and since the spandex yarn 20 is not used in knitting the welt, the heel, and the toe of the stocking, it is necessary to disengage the drive wheel 23 from the disc 22 during the knitting of these portions of the stocking. This is accomplished by pivoting the yoke 28 in such a manner that the drive wheel 23 is withdrawn from contact with the disc 22 during idle periods of the spandex yarn 20.

The yokes 28 is provided with a rib 48 (FIGURE 3) which is positioned in a slot 49 in a block 50. The device is constructed in such a manner that when the back of the rib 48 is in contact with the bottom of the slot 49 the rubber ring 24 on the drive wheel 23 is spaced from the disc 22 so that the yarn package 19 is not driven.

To move the drive wheel 23 into contact with the disc 22 a camming pin (FIGURE 3) is utilized. The camming pin 40 is rotatably mounted in a bore 41 extending through the block 50 and has a portion thereof cut away to leave thereon a fiat face 42 which is aligned with and in the plane of the bottom surface of the slot 49 when the drive wheel 23 is in its neutral position. It can readily be seen that rotation of the camming pin 40 in the bore 41 will move one side of the surface 42 outward from the plane of the bottom of the slot 49 to urge the driving wheel toward and into relationship with the disc 22.

An arm 45 secured to the end of the camming pin 40 is connected to an armature 46 of a solenoid 47 (FIG- URE 2) so that energization of the solenoid 47 pivots the camming pin 40 to force the drive wheel 23 into driving relationship with the disc 22. When the solenoid 47 is not energized the drive wheel 23 is held in disengaged position by a tension spring 51 (FIGURE 2) connected between pins 52 and 53, the pin 52 being secured to the yoke 28 and the pin 53 being secured to the block 50.

Operation of the solenoid 47 is controlled by a limit switch 57 (FIGURE 1) secured to an arm 58 mounted on the upper end of the bracket 11. The switch 57, which is a normally open switch of a well known type, is operated by an arm 59 pivotally attached to the switch and having at the free end thereof a grooved guide roller 60 over which the elastic yarn 20 passes. A spring 61 secured between the switch 57 and one end of the arm 59 urges the arm 59 and the roller 60 toward an uppermost position, at which position the switch 57 is open. Closure of the switch 57 occurs when the yarn 20 pulls the roller 60 and the arm 59 downward against the action of the tension spring 61.

To control the speed at which the yarn package 19 is driven by drive wheel 23, a sensing wheel 66 positioned in contact with the yarn package 19 is connected to the drive wheel 23 for moving the drive wheel 23 radially inward on the disc 22 as the diameter of the yarn package decreases. The sensing wheel 66 is rotatably mounted on a bar 67 which is slidably mounted on the lower end of the bracket 11. Tension springs 68 connected between the bracket 11 and a pin 69 extending through the lower end of the bar 67 urge the sensing wheel upward against the yarn package 19.

The bar 67 has connected thereto an arm 73 (FIGURE 2) having in the free end thereof a slot 74 for receiving an eccentric pin 75. The eccentric pin 75 is secured to a shaft 73 (FIGURE 3) which is rotatably mounted in the block and which has secured to the other end thereof a ratchet gear 79. The block 50 is dovetailed into and slidably mounted on a support block 81 secured to the bracket 11 so that as the sensing wheel moves upward or downward the arm 73 pushes upward or downward on the eccentric pin '75 to thereby move the block 50 and the drive wheel 23. I11 this manner the drive wheel 23 is interconnected with the sensing wheel 66 so that the drive wheel moves radially inward on the disc 22 as the yarn package 19 decreases in diameter, so that the spandex yarn 20 is removed from the package 19 at a constant speed and under a constant tension.

FIGURE 4 illustrates a support stocking 86. The elastic yarn 20 is used throughout the stocking 86 except for the welt 87, the heel 88 and the toe 89. The nylon yarn is also used with the spandex yarn in the remainder of the stocking. In a two-feed machine the nylon yarn and the spandex yarn are fed together to one knitting position while a second nylon yarn is fed to the other knitting position. This results in a stitch such that alternate courses are composed solely of nylon yarn with the courses therebetween being composed of nylon and spandex yarns knitted in together. During the knitting of the welt 87, the heel 88 and the toe 89 the knitting machine does not apply a pulling force to the elastic yarn 20, so that the guide roller 60 can move to an uppermost position and thereby open the switch 57 to disable the solenoid 47 and thereby disconnect the drive wheel 23 from the disc 22.

While the above described apparatus drives the yarn package 19 at a constant speed it is desirable to uniformly decrease this speed during the knitting of the lower calf portion 93 of the stocking 86. This is accomplished by changing the position of the drive wheel 23 relative to the sensing wheel 66 in the following manner. The drive shaft 27 has secured thereto a worm gear 93 meshed with a spur gear 94 which is secured to a shaft 96 rotatably mounted in the yoke 28. The end of the shaft 96 has mounted thereon a pawl 97 (FIGURE 1), the pawl 97 being mounted eccentrically on the shaft 96 so that rotation of the shaft 96 reciprocates the pawl 97. A tension spring 98 connected to the block 50 urges the free end of the pawl 97 upward into contact with the teeth on the ratchet gear 79. Reciprocation of the pawl 97 causes the ratchet gear 79 to slowly turn, thereby turning the shaft 78 and the eccentric pin to change the position of the drive wheel 23 relative to the sensing wheel 66. Since the drive shaft 27 is driven continuously, the pawl 97 is reciprocated continuously. In order to prevent the continuously reciprocating pawl 97 from continuously moving the ratchet gear 79, the gear 79 is provided with a toothless or blank portion 99. When the end of the pawl 97 reaches the toothless or blank portion 99 the eccentric pin 75 will be at its uppermost position so that the drive wheel 23 will be spaced at its maximum distance from the center of the disc 22. In this position the yarn package 19 is being driven at its maximum speed. This is the speed at which the yarn package 19 is driven during the knitting of the upper calf portion of the stocking 36. The ratchet gear 79 does not turn during this portion of the knitting operation, since the pawl 97 merely moves back and forth along the toothless portion 99.

When the knitting machine is ready to begin knitting the lower calf portion 93 a pin 102 mounted on a drum 103 engages a contactor 104 of a limit switch 105 and closes the switch. The drum 103- is a conventional part of the hosiery machine. Closure of the switch 105 applies power to a solenoid 109 having the armature thereof connected by a stiff tension spring 110 to a plate 111 which is slidably mounted on the frame 11. The solenoid 109 pulls the plate 111 upward so that a pawl 112 mounted on the plate 111 will move the ratchet gear 79 a sufiicient distance that the tooth following the toothless portion 99 can be engaged by the pawl 97. The pawl 112 is urged into engagement with the ratchet gear 79 by a spring 113. In this manner the apparatus is triggered to begin feeding the elastic yarn 2% at a speed which decreases throughout the knitting of the lower calf portion 93 of the stocking 86. The plate 111 is urged downwardly by a tension spring 116 which is connected between a pin 117 mounted on the base and a pin 11% secured to the plate 111.

During the knitting of the lower calf portion 93 the pawl 97 is reciprocatcd to sequentially engage the teeth extending counterclockwise (FIGURE 1) around the gear 79 from the toothless or blank portion 99. This slowly moves the drive wheel 23 radially inward relative to the disc 22 and the sensing wheel 23 to decrease the driving speed of the yarn package 19. This causes the yarn to be fed at a steadily decreasing rate as the lower calf portion 93 of the stocking 86 is knitted.

By the time the knitting machine has progressed to the lower end of the lower calf portion 93 the ratchet gear 79 has been rotated by the pawl 97 to the point where the end of the pawl 97 is in engagement with a second toothless or blank portion 121 of the ratchet gear 79 (FIG- URE 1). At this point the eccentric pin 75 is in its lowermost position so that the drive wheel 23 is as near the axis of the yarn package 19 as it ever is during the knitting operation. Thus, the yarn package 19 is being driven at this stage at its minimum speed. Since the end of the pawl 97 is in engagement with the second toothless portion 121, reciprocation of the pawl 97 does not turn the ratchet gear 79so that the yarn package 19 is driven at its minimum speed during the knitting of the ankle and foot portions of the stocking 86.

When the knitting machine begins knitting the toe 89 a second pin 122 on the drum engages the contactor 104 of the switch 195 to energize the solenoid 109. This pulls the plate 111 upward, the pawl 112 moving the ratchet gear 79 a distance sufficient to allow the pawl 97 to engage the tooth on the gear 79 which immediately follows the toothless space 121. The reciprocating pawl 97, during the knitting of the toe 89 and the welt 87, rotates the ratchet gear 79 to move the eccentric pin back to its uppermost position where the drive wheel 23 is positioned at its extreme radial distance on the disc 22. However, the drive wheel 23 is out of contact with the disc 22 during this stage so that the yarn package is not driven until the welt 87 is knitted, at which time the pawl is again positioned at its starting position on the toothless or blank space 99.

The above procedure is repeated once for each stocking knitted. From the above it can readily be seen that the yarn package 19 is driven at a constant, maximum speed during the knitting of the upper calf portion of the stocking 86, is driven at a steadily decreasing speed during the knitting of the lower calf portion 93 and is driven at a minimum speed during the knitting of the ankle and foot portions of the stocking. Thus the spandex yarn is fed into the hosiery knitting machine at a speed which is substantially proportional to the circumference of the stocking at the various points thereon. By using this device to control the feed of the spandex yarn the resulting stocking will operate as a support stocking but does not have the undesirable appearance of a support stocking. In fact, this stocking has the appearance of an ordinary sheer nylon stocking.

It is to be understood that the embodiment disclosed herein can be altered or amended and numerous other embodiments may be contemplated without departing from the spirit and scope of the invention.

What is claimed is:

1. Apparatus for feeding an elastic yarn to a machine for knitting seamless stockings, comprising a frame mounted on the knitting machine, a bobbin holder rotatably mounted on the frame for supporting a package of elastic yarn, means on the frame for driving the bobbin holder to rotate the yarn package to feed the elastic yarn to the knitting machine, driving means on the frame and connected to the bobbin holder for rotating the bobbin holder, said driving means being disengageable from the bobbin holder, said driving gears also being adjustable so as to drive the bobbin holder at different speeds, means on the frame responsive to tension in the elastic yarn for disengaging the driving means from the bobbin holder when said tension drops below a predetermined value, and means on the frame for adjusting the driving means to adjust the speed of the bobbin holder, said adjusting means being controlled by the knitting machine to decrease the speed of the bobbin holder at a substantially uniform rate during the knitting of the lower calf portion of the stocking.

2. Apparatus for feeding an elastic yarn to a machine for knitting seamless stockings, comprising a frame mounted on the knitting machine, a bobbin holder rotatably mounted on the frame for supporting a package of elastic yarn, said bobbin holder having on one end thereof a disc, a rotating drive wheel mounted for movement into and out of contact with the disc for driving said disc to rotate the yarn package, said driving wheel also being mounted for radial movement relative to the disc, a sensing wheel positioned in contact with the yarn package, said sensing wheel being mounted for movement along the radius of the yarn package as the size of the yarn package decreases, means interconnecting the sensing wheel and the drive wheel for moving the drive wheel radially relative to the disc as the sensing wheel moves radially, said interconnecting means being adjustable to move the drive wheel from a maximum radial position relative to the sensing wheel to a minimum radial position relative to the sensing wheel, and means controlled by the machine for so adjusting the interconnecting means during the knitting of the lower calf portion of the stocking.

3. Apparatus for feeding an elastic yarn to a machine for knitting seamless stockings, comprising a frame mounted on the machine, means rotatably mounted on the frame for supporting a package of elastic yarn, said support means having on the end thereof a disc, a rotating drive wheel mounted on the frame, said drive wheel being movable into and out of driving contact with the disc, said wheel also being movable radially across said disc, means on the frame for moving the drive wheel into contact with the disc to drive the yarn package, a sensing wheel positioned in contact with the yarn package, adjustable means interconnecting the sensing wheel and the drive wheel for moving said drive wheel radially inward on said disc as the yarn package decreases in size, and means controlled by the machine for adjusting the interconnecting means to move the drive wheel radially inward relative to the sensing wheel when the machine is knitting the lower calf portion of the stocking.

4. Apparatus for feeding an elastic yarn to a machine for knitting seamless stockings, comprising a frame mounted on the machine, a bobbin holder rotatably mounted on the frame for carrying a package of elastic yarn, said bobbin holder having on the end thereof a disc, a drive wheel rotatably mounted on the frame, said wheel being connected to and driven by the knitting machine, a block mounted on the frame, a yoke mounted on the block, a drive wheel rotatably mounted on the yoke, said yoke being pivotally mounted on the block for moving the wheel into and out of driving engagement with the disc, said block being slidably mounted on the frame for moving the yoke to move the drive wheel radially across the disc, a sensing wheel movably mounted on the frame for engagement with the yarn package, means connected to the sensing wheel for urging said wheel into engagement with said yarn package, a shaft rotatably mounted on the block and having thereon an eccentric pin, an arm interconnecting the eccentric pin and the sensing wheel so that movement of the sensing wheel in responses to changes in the diameter of the yarn package radially adjusts the position of the drive wheel to maintain a constant yarn feed speed, and means connected to and driven with the drive wheel for rotating the shaft and the eccentric pin to thereby radially adjust the position of the drive wheel relative to the sensing wheel.

5. Apparatus for feeding an elastic yarn to a machine for knitting seamless stockings, comprising a frame mounted on the machine, a bobbin holder rotatably mounted on the frame for carrying a package of elastic yarn, said bobbin holder having on the end thereof a disc, a block mounted on the frame, a yoke mounted on the block, a drive wheel rotatably mounted on the yoke for engaging the face of the disc to drive the yarn package, said yoke being pivotally mounted on the block for moving the drive Wheel into and out of driving engagement with the face of the disc, said block being slidably mounted on the frame for moving the yoke to move the drive Wheel along a radius of the disc, means driven by the knitting machine for continuously rotating the drive wheel, a bar slidably mounted on the frame, a sensing wheel carried by the bar, resilient means interconnecting the bar and the frame for urging the sensing wheel into sensing contact with the periphery of the yarn package, a shaft rotatably mounted on the block and having extending axially from one end thereof an eccentric pin, an arm secured to the bar and connected to the eccentric pin so that movement of the sensing wheel radially relative to the bobbin holder moves the block to thereby move the drive Wheel radially across the face of the disc, a ratchet gear secured to the shaft, a reciprocating pawl mounted on the yoke and driven by the drive Wheel rotating means for engaging and turning the ratchet gear to turn the shaft and the eccentric pin and thereby adjust the position of the drive wheel relative to the sensing wheel, a tension spring interconnecting the block and the yoke for urging the yoke and the drive wheel away from the disc, a cam mounted on the block for engaging and moving the yoke to thereby move the drive wheel into engagement with the disc, and means responsive to tension in the elastic yarn for actuating the cam.

References Cited UNITED STATES PATENTS 1,726,568 9/1929 Jones 66-132 2,132,174 7/1938 Lindley 66-132 2,334,058 11/1943 Bassist 66-132 X 2,400,525 5/1946 Amidon 66-132 X 2,441,443 5/1948 Reed 66-146 X 2,708,841 5/1955 Lumsden 66-132 2,750,773 6/1956 Virchaux et al. 66-132 3,209,558 10/1965 Cargill 66-132 WILLIAM CARTER REYNOLDS, Primary Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,390,552 July 2, 1968 Noble T. King It is certified that error appears in the above identified patent and that said Letters Patent are hereby correeted as shown below:

Column 5, line 68, "gears" should read means Signed and sealed this 31st day of March 1970.

( L) Attest:

Edward M. Flemher', Ir. WILLIAM E. SCHUYLER, JR.

Attesting Officer Commissioner of Patents

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