US 3478544 A
Description (OCR text may contain errors)
Nov. 18, 1969 E. P. HOMAN 3,478,544
METHOD OF KNITTING SHEER SEAMLESS SUPPORT STOCKINGS Filed Sept. 25, 1967 v 4 Sheets-Sheet 1 H ,(L; 10 P 3 99.407 5a INVENTORZ ELWOOb P. HOMAN ATTORNEYQ E- P. HOMAN Nov. 18, 1969 METHOD OF KNITTING SHEER SEAMLESS SUPPORT STOCKINGS Filed Se t. 25, 1967 4 Sheets-Sheet 2 MENTOR: ELwoob P HOMAN BYM ATTORNEY I Nov. 18, 1969 I E. P. HOMAN 3,478,544
METHOD OF KNITTING SHEER SEAMLESS SUPPORT STOCKINGS Filed Sept. 25, 1967 4 Sheets-Sheet 3 ATTORNEYS Nov. 18, 1969 E. PVHOMAN 3,478,544
METHOD OF KNITTING SHEER SEAMLESS SUPPORT STOCKINGS Filed Sept. 25, 1967 4 Sheets-Sheet 4 F 7:15 INVENTORI ELWOOb P. HOMAN ATTORNEYS United States Patent 3,478,544 METHOD OF KNITTING SHEER SEAMLESS SUPPORT STOCKINGS Elwood P. Homan, Wytheville, Va., assignor, by mesne assignments, to Kayser-Roth Corporation, New York, N.Y., a corporation of New York Filed Sept. 25, 1967, Ser. No. 670,248 Int. Cl. D04b 15/06, 9/46 US. Cl. 66108 4 Claims ABSTRACT OF THE DISCLOSURE This invention is directed generally to the production of ladies seamless sheer support stockings and more particularly to an improved method of knitting which enhances the sheer appearance of the stockings and provides the proper support on the leg of the wearer.
It is known to knit a support stocking on a multi-feed circular hosiery knitting machine by feeding an inelastic body yarn to every needle and forming stitch loops thereon at one knitting station while feeding a covered elastic yarn to alternate needles and forming stitch loops thereon at the next knitting station. This method of knitting a support stocking is disclosed in the York et al. Patent No. 3,250,092, issued May 10, 1966. Support stockings knit in accordance with the method of this patent have an open mesh and sheer appearance with a gradually reducing compressive effect from the ankle upwardly to the top of the stocking and have rreceived widespread acceptance by both manufacturers and consumers.
As pointed out in this York et al. patent, it is important to feed the inelastic body yarn under substantially no tension and the elastic yarn under a slight tension while forming normal size stitches of the body yarn and abnormally large stitches of the elastic yarn. In this patent, it is suggested that the tension on the elastic yarn be maintained from about 6 to 8 grams and that the large stitches of the elastic yarn be formed by drawing the needles down to an abnormally low stitch position by means of the stitch cams. This method requires one adjustment of the stitch cams at the elastic yarn knitting station during the knitting of the leg portion of the stocking and another adjustment of the stitch cams to knit plain fabric of inelastic yarn, such as when the welt is to be knit in a two-feed manner by feeding body yarn to both knitting stations. Unless this adjustment of the 'stitch cams is very accurate, stitch loops of different sizes will be formed at each knitting station and cause coursewise streaks in the welt. The formation of large stitches of the elastic yarn also increases the length of elastic yarn that is drawn into the stocking.
This York et al. patent also suggests that the shaping of the leg portion of the stocking be accomplished during the knitting operation by the conventional fashioning mechanism which gradually reduces the stitch size as the leg is being knit. By the conventional process, the leg portion of the stocking gradually is reduced and uniformly tapers from the ankle to a position below the 3,478,544 Patented Nov. 18, 1969 ice welt. While this method of fashioning is widely used in the knitting of both regular and support stockings, I have now discovered a more efiicient method of shaping for support hosiery so as to provide the desired amount of support on all portions of the leg of the wearer.
With the foregoing in mind, it is an object of the present invention to provide an improved method of forming support stockings which enhances the sheer appearance and overcomes the above-mentioned and other difficulties encountered in the knitting of ladies sheer seamless support stockings by the known methods.
Generally, the enhanced sheer appearance is obtained by incorporating a greater length of the inelastic body yarn into the fabric while reducing the length of elastic yarn therein. In accordance with the present method, this is achieved by drawing the inelastic yarn down in front of the nibs of the sinkers and moving the sinkers inwardly at an earlier than normal position at the knitting station to form relatively large inelastic yarn stitches in every Wale, and knitting the elastic yarn on alternate needles while drawing the elastic yarn down behind the nibs of the sinkers and maintaining a relatively high tension on the elastic yarn.
The relative dilference in size of the stitch loops formed of the elastic and inelastic yarns and the high tension placed on the elastic yarn cooperate in such a manner as to increase the length of the inelastic yarn incorporated in the stocking, relative to the length of the elastic yarn incorporated therein. This method of knitting also causes the elastic yarn to be incorporated in the finished stocking in a more sinuous path than in stockings knit in accordance with the usual method.
In accordance with a further feature of the method of the present invention, the support stocking is fashioned during knitting by varying the size of the stitch loops in such a manner as to obtain the desired amount of compressive force in particular areas of the stocking. To this end, certain portions of the leg of the stocking are fashioned by gradually decreasing the stitch size being knit at both knitting stations and the stitch size is main tained constant at both knitting stations during the knitting of other portions of the leg of the stocking. For example, it is preferred that the upper portion of the leg, just below the turned welt, and a medial portion of the leg be knit with stitch loops of a uniform size and that the lower portion of the leg and the intermediate section of the leg between the upper and medial portions be knit while the stitch size is gradually reduced at both knitting stations.
Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which FIGURE 1 is a developed view of the needle operating cams and jack selecting and operating cams of a preferred type of machine on which the present method is carried out;
FIGURE 2 is a sectional plan view of the sinker cap of the machine, and illustrating the mechanism for, at times, retarding the rotational movement of the sinker cap to cause the sinkers to be advanced at an earlier than normal position at the main or inelastic knitting station;
FIGURE 3 is an enlarged isometric view of the sinker cap rotation retarding mechanism, looking inwardly in the direction of the arrow 3 in FIGURE 2;
FIGURE 4 is a view similar to FIGURE 3, but showing the sinker cap retarding arm in operative position with the sinker cap rotated to its limit in a counterclockwise direction;
FIGURE 5 is a fragmentary isometric view of the size control drum of the knitting machine and illustrating the manner in which the fashioning cam is operated to vary the fashioning of the stocking during knitting;
FIGURE 6 is a fragmentary isometric view of a portion of the latch ring, illustrating the manner in which the yarn feed fingers are mounted and supported at the auxiliary or elastic yarn knitting station;
FIGURE 7 is a vertical sectional view through the needle cylinder at the auxiliary knitting station and illustrating the manner in which the needle lowering cam is supported for providing substantial separation between those needles which pick up and knit the elastic yarn and those needles across which the elastic yarn is floated;
FIGURE 8 is a fragmentary sectional plan view of the needle lowering cam, taken substantially along the line 88 in FIGURE 7;
FIGURE 9 is an elevational view of a sinker and the upper portion of a needle, illustrating their relative positions at the auxiliary knitting station as the needles are lowered to draw the elastic yarn over the stitch forming ledges behind the nibs of the sinkers;
' FIGURE 10 is a view similar to FIGURE 9, but illustrating the relative positions of a needle and sinker at the main knitting station where the inelastic body yarn is drawn down over the stitch forming ledges in front of the nibs of the sinkers;
FIGURE 11 is a side elevational view of a support stocking blank, as it comes from the knitting machine, and illustrates the manner in which the stitch loops are graduated in two separate portions of the leg of the stocking blank;
FIGURE 12 is a side elevational view of the finished support stocking; and
FIGURE 13 is a greatly enlarged view of a small portion of the fabric of the stocking, being in the area of the dotted rectangle 13, in FIGURE 12, and illustrating the manner in which the elastic yarn is incorporated in a sinuous path in the stitches of inelastic body yarn to provide the sheer, open-mesh appearance.
In the drawings, portions of a Reading Mark III, two-feed, 403 needle, circular knitting machine are shown. Only those portions of the machine are shown which are considered necessary to an understanding of the present invention. Further details of this type of machine are shown in the Reading Mark III parts catalogue published by Textile Machine Works and copyrighted in 1962. Reference may also be made to US. Patent Nos. 3,252,307 and 3,307,377, which illustrate portions of this type machine.
While the method of the present invention is described as being carried out on this particular type of circular hosiery knitting machine, it is to be understood that the method may also be practiced on other types of circular hosiery knitting machines by making very slight modifications, similar to those modifications herein described in connection with the Reading machine. The conventional portions of the knitting machine are first described; then the modifications are described which have been necessary in order to knit a support stocking in accordance with the method of the present invention; and finally, the method of the present invention is described as practiced on the modified machine.
The machine is of the multi-feed type and in the present instance, is provided with two knitting stations, generally designated as the respective main and auxiliary knitting stations 10, 11 in FIGURE 1. The cams which operate on the butts of the needles 12 at the main station 10 (FIGURE 1) include a forward stitch cam 13, a reverse stitch cam 14, a top center cam 15, and a lower center or needle leveling cam 16. Needle leveling end cams 17, 18 are provided adjacent opposite sides of the respective forward and reverse stitch cams 13, 14, and guard cams 19, 20 are positioned above the respective end cams 17, 18.
The usual needle raising and lowering cams are supported for radial movement into and out of operative position. These cams are shown in the dotted line inoperative position and may be moved inwardly to engage the butts of the needles 12 as they approach the main knitting station 10. These needle cams include a needle raising cam 21, a needle lowering cam 22, switch cams 23, 24, transfer cams 25, 26, and a divider cam 27.
An auxiliary jack 30 and a pattern jack 31 are provided beneath each latch needle 12, and as the pattern jacks 31 approach the main knitting station 10, the upper ends are engaged by a presser cam 32 to rock the lower pattern butt portion of the pattern jack 31 outwardly of the needle cylinder so that the butts thereon may be engaged by a bank of selector levers 33. If a butt on the pattern jack 31 is engaged by a selector lever 33, the lower end of the pattern jack is rocked back inwardly. The selector levers 33 are operated from the usual pattern drum, not shown, and the pattern drum and butts on the pattern jack 31 are set up to provide the desired pattern in the stocking.
A jack raising cam 34 is provided to engage the stepped lower butt on the pattern jack 31 if it is not rocked back intothe needle cylinder by the selector levers 33. Thus, selected ones of the pattern jacks 31 and corresponding auxiliary jacks 30 and needles 12 will be raised by the jack raising cam 34 while the remaining pattern jacks will not be raised. The main knitting station 10 is also provided with a plurality of yarn feed fingers, only one of which is shown at 36 in FIGURE 1. These yarn feed fingers 36 are supported for movement into and out of yarn feeding position in a conventional throat opening, not shown.
The auxiliary knitting station 11 includes needle butt engaging cams comprising a stitch cam 40, an upper center cam 41, and a needle leveling end cam 42. The auxiliary knitting station 11 is usually provided with a lower center or leveling cam which is supported below the center cam 41. In accordance with the present invention, the center cam has been removed and replaced by a radially movable needle lowering cam, to be later described.
A plurality of conventional body yarn feed fingers 43 (FIGURES 6 and 7) are pivotally supported for movement into and out of yarn feeding position in a throat opening 44, formed in the latch ring 45. The yarn feed fingers 43 are normally urged downwardly to the opera tive or feeding position by suitable springs and may be raised to the inoperative position by conventional thrust rods 46 (FIGURE 6). A special yarn feed finger (to be later described) is also provided at the auxiliary knitting station for use in feeding a covered spandex yarn.
A jack presser cam 50 is provided in advance of the auxiliary knitting station 11 to rock the lower ends of the jacks 31 outwardly so that they may be selectively engaged and pressed inwardly by a bank of selector levers 51. Those jacks 31 which are engaged by the selector levers 51 are not raised by a jack raise cam 52 (FIGURE 1) while the remaining jacks 31 are raised thereby. The selection of the needles to be raised at the auxiliary knitting station 11 Will be presently described.
As shown in FIGURE 7, the latch needles 12 and corresponding jacks 30, 31 are supported for vertical sliding movement in slots in the needle cylinder 54 and a radially slotted sinker bed 55 is supported on the upper end of the needle cylinder 54. Sinkers 56 (FIGURES 7, 9 and 10) are supported for radial movement in the radial slots of the sinker bed 55 and for operation between the needles 12. The sinkers 56 are each provided with an upstanding operating butt 57, a nib 58, a stitch drawing ledge 59 behind or outside of the nib 58, and a stitch drawing ledge 60 in front of or inside of the nib 58. It will be noted in FIGURES 9 and 10 that the stitch drawing ledge 59 is slightly higher than the stitch drawing ledge 60, and the needles 12 may draw the yarn down over either of these ledges, for purposes to be presently described in connection with the method of the present invention.
The upstanding butts 57 0f the Sinkers 56 ride in a cam track 61 in a sinker cap '62 (FIGURE 2) and the sinkers 56 are normally urged to their innermost position by a spring band 63 (FIGURES 9 and As the sinkers 56 approach the main knitting station, their butts engage a sinker withdrawing cam 65 (FIGURE 2) and the sinkers 56 are withdrawn or retracted to substantially the position shown in FIGURE 10 where the needles will draw the yarn downwardly over the stitch drawing ledges 60, at the main knitting station. During conventional knitting, the sinkers 5-6 are moved inwardly as their butts engage an inclined cam surface 67 on the sinker cap 62 (FIGURE 2) to press the cast-off stitches inwardly after the needles have been drawn down to stitch drawing level.
A sinker withdrawing cam 70 is supported at the auxiliary knitting station for radial movement between the solid-line and dotted-line positions shown in'FIGURE 2. The sinker cam 70 is fixed on the inner end of a stem portion 71 and an operating abutment 72 is provided on the outer end thereof. The abutment 72 is engaged by the usual operating linkage, not shown, to selectively position the cam 70 in the desired position. When the sinker cam 70 is in the innermost solid-line position shown in FIGURE 2, the sinkers 56 are not retracted at the auxiliary knitting station 11, but remain in the innermost position so that the needles 12 draw the yarn down over the outer stitch drawing ledges 59, in the manner illustrated in FIGURE 9 and for purposes to be presently described. At times, the sinker cam 70 will be moved outwardly to the dotted-line position so that the sinkers 56 are withdrawn at the auxiliary knitting station 11 and the needles draw the yarn down over the stitch drawing ledges 60, in front of the nibs 58. When the sinkers 56 are withdrawn by the cam 70, they are moved back inwardly by an inclined cam 74 on the sinker cap 62 (FIGURE 2).
As shown in FIGURE 2, the sinker cap 62 is provided with spaced apart outwardly extending lugs 75, 76 which are provided with respective threaded stop abutment screws 77, 78. The inner ends of the abutment screws 77, 78 normally engage opposite sides of a latch ring post 80 to thereby limit relative rotational movement of the sinker cap 62, during reciprocation of the needle cylinder 54. The sinker cap 62 is shown in FIGURE 2 in the neutral position; i.e., with the ends of the abutment screws 77, 78 substantially equally spaced from opposite sides of the post 80.
As the normal forward rotation is imparted to the needle cylinder 54, in a counterclockwise direction in FIGURE 2, the free end of the abutment screw 77 will move against the post 80 and limit counterclockwise movement of the sinker cap 62. When movement is imparted to the needle cylinder in the opposite direction, as during reciprocation, the free end of the abutment screw 78 will engage the post 80 and limit clockwise movement of the sinker cap 62. This limited movement of the sinker cap 62 is conventional and, in accordance with the present invention, means (to be later described) is provided for limiting the amount of counterclockwise movement of the sinker cap 62.
A front pattern shaft 82 (FIGURE 5) is rotatably supported in the lower front portion of the machine frame 83 and a left-hand pattern drum 84 is fixed thereon. Other conventional pattern drums, not shown, are supported on the shaft 82, and the shaft 82 and the drums fixed thereto are rotated in a predetermined sequence, according to the pattern provided on the main pattern chain, not shown. The length of stitch knit in various portions of the stocking is normally controlled by raising and lowering the needle cylinder 54, relative to the stitch cams, to correspondingly lengthen and shorten the stitch being formed.
The vertical position of the needle cylinder 54 is normally controlled by means of a quality lever, a portion of which is shown at 86 in FIGURE 5. The lever 86 is normally provided with a plurality of cam pins, not
shown, which engage different cam races of a size control drum, not shown. One end of a graduating arm 90 (FIGURE 5) is attached to the quality lever 86 and has a cam pin 91 in its free end which is adapted to engage and ride on a graduating cam 92, fixed on a graduating rack wheel 93, supported for rotation on the pattern shaft 82.
The forward end of a racking lever 95 (FIGURE 5) is in engagement with the teeth of the rack wheel 93 and the rear end is pivotally connected to an oscillating plate 96 which is, in turn, fixed on the end of the quadrant shaft of the machine so that continuous oscillation is imparted to the racking lever 95. During normal operation of the knitting machine, the size of the stitches being formed is at times controlled by the graduating cam 92 and the graduating arm 90. The rack wheel 93 is normally moved in a continuous step-by-step manner so that the size of the stitch loop being knit throughout the lower part of the leg of the stocking is gradually reduced in a fairly constant manner, depending upon the particular configuration of the graduating cam 92.
This cam 92 is usually designed so that the stocking blank gradually tapers from the calf to the ankle, where the stitches are made as small as possible. In accordance with the present invention, means is provided for interrupting the movement of the graduating cam 92 at predetermined intervals so that the stitch loop size will remain the same. This mechanism will be presently described in detail.
As shown in FIGURES 7 and 8, a circular bed .plate 99 is supported in a conventional manner and surrounds the needle cylinder 54 to support the conventional needle butt engaging cams. The bed plate 99 also supports a special needle lowering cam at the auxiliary knitting station 11, to be presently described in detail. The parts heretofore described are conventional, except where noted, and the parts will now be described which have been added in order to carry out the present method.
In accordance with the present invention, an inelastic yarn, indicated at Y in FIGURE 1, is fed to all the needles at the main feeding station 10 and through the yarn feed finger 36 and an elastic yarn, indicated at E in FIGURE 1 is fed to alternate needles at the auxiliary knitting station 11 and through a special feed finger 100. The feed finger 100 (FIGURE 6) is provided with a special ceramic guide eye 101 and extends inwardly slightly inside of the inner surface of the latch ring 45 at the throat opening 44 so that the elastic yarn E does not drag over and engage the metal surface at the corners of the throat opening 44.
The elastic yarn E preferably has a spandex core with a nylon covering, and if it is permitted to drag over the corners of the throat opening 44, the covering yarn may be skinned back or disrupted, and variable tension will be imparted to the yarn as it is fed through the needles, thereby resulting in a non-uniform product. Thus, by providing the horizontally disposed guide eye 101 (FIG- URE 6) and positioning the finger 100 so that it is inside of the latch ring 45, the elastic yarn E does not run against any portion of the machine and the yarn is fed to the needles under uniform tension.
A needle lowering cam 104 is provided at the auxiliary knitting station 11 (FIGURE 1) to provide a wide separation between those needles which are selected to pick up and knit the elastic yarn E and those needles which are not raised to pick up the elastic yarn E. This cam 104 insures a positive floating of the elastic yarn inside of those needles which are not raised at the auxiliary knitting station 11.
In accordance with the present invention, every other needle is raised by the jack raising cam 52 and the pattern jacks 31 so that their butts are raised to pass along a dotted line pathway 106 and their hooks move along a dotted line pathway 107 to pick up the elastic yarn E therein. Those needles which are not raised move along a level path until their butts engage the needle lowering cam 104. The butts of the needles are then lowered by the cam 104 to move along a dotted line path 108 While their hooks are lowered to move along a dotted line path 109 and below the yarn feed finger 100 a sufiicient distance that they do not pick up the elastic yarn E and so that the elastic yarn will be floated inside these needles, in a positive manner. As shown in FIGURES 7 and 8, the needle lowering cam 104 is supported for radial move ment into and out of operative position in a cam block 110, which is in turn fixed on the bed plate 99. The outer stem portion of the cam 104 is provided with an abutment 111 which is engaged by the upper end of a bell crank lever 112.
A tension spring 113 normally urges the cam 104 to an innermost position, which is adjustable by means of an adjustment stop screw 114. The cam 104 may be moved to an inoperative position by counterclockwise movement of the bell crank 112, by means of a Bowden wire cable 115, one end of which is connected to the bell crank 112 and the other end of which is operated by a suitable lever on a conventional pattern drum, not shown. The bell crank 112 is suitably supported for pivotal movement on a bracket 116 (FIGURE 7) which is in turn fixed on the bed plate 99.
In accordance with the present invention, the shifting or rotational movement of the sinker cap 62 in a counterclockwise direction (FIGURE 2) is limited by means of a bunter plate 120, the inner end of which is fixed on the adjustment stop screw 77 and the outer end of which is provided with an adjustably supported bunter or stop screw 121. The free head end of the hunter 121 is normally adapted to engage the vertical leg 122 of a stop bracket which has a horizontal leg 123 fixed to the upper end of the post 80 (FIGURES 3 and 4). During normal operation with the needle cylinder rotating continuously in a counterclockwise direction, the sinker cap 62 will be rotated to a position where the hunter stop 121 remains in engagement with the vertical leg 122 of the stop bracket. With the sinker cap 62 in this position, the sinkers will be moved inwardly at the main knitting station by the inclined cam surface 67 (FIGURE 2) and in the conventional manner; i.e., after the needles have been lowered to the full stitch drawing position.
As is well known, by advancing the sinker cap so that the sinkers are advanced or moved inwardly at an earlier than normal position, the yarn is pushed inwardly between the needles by the nibs 58 of the sinkers and additional yarn is drawn into each stitch loop so that the stitch loops are somewhat enlarged. In the present instance, the counterclockwise rotational movement of the sinker cap 62 is retarded or limited by a bell crank control lever 125 which has a cammed upper end portion 126 and is pivotally supported as at 127 on the lower end of the vertical leg 122 of the stop bracket (FIGURE 4). A tension spring 128 is connected at one end to the bell crank control lever 125 and its other end is connected to the horizontal arm 123 of the support bracket to thus normally urge the control lever 125 to the inoperative position shown in FIGURE 3 so that the stop bunter 121 will directly engage the surface of the vertical leg 122.
One end of a Bowden wire cable 130 is connected to the bell crank 125 and the other end is suitably connected to a control lever which is operated by the conventional cams on the usual pattern drum, not shown. The cable 130 will, at times, move the bell crank 125 from the inoperative position shown in FIGURE 3 to the operative position shown in FIGURE 4 so that the hunter stop 121 will engage the upper cam surface 126 of the bell crank 125 and thereby prevent rotation of the sinker cap 62 to the full counterclockwise position.
In order to positively hold the sinker cap 62 in the correct adjusted position, a Z-shaped support arm 132 (FIGURES 3 and 4) is connected at one end to one side of the bell crank 125 and its other end is provided with an adjustable stop screw 133. Thus, as the bell crank 125 is moved from the inoperative position shown in FIG- URE 3 to the operative position shown in FIGURE 4, the adjustable bunter 133 moves against the outer surface of the bunter plate 120 and the sinker cap 62 is held in a secure position by the cam surface 126 engaging the hunter stop 121.
In accordance with the present invention, means is provided for interrupting the movement of the graduating cam 92 (FIGURE 5) so as to maintain the stitch loop size uniform during a predetermined portion of the knitting of the leg portion of the stocking. In the present instance, this interrupting means includes an operating pin 137 fixed to the inner surface of the pattern drum 84 (FIGURE 5) and a roller 138, secured to a medial portion of the racking lever 95. The roller 138 is positioned to be engaged by the pin 137 to lift the racking lever out of engagement with the rack wheel 83 and stop step-by-step rotation of the rack wheel 93 and the graduating cam 92, for purposes to be later described.
METHOD OF OPERATION During the knitting of a stocking blank, such as is shown in FIGURE 11, the knitting usually proceeds from the top to the bottom and will be described in this manner in connection with the present invention. It is preferred that the upper end of the stocking blank (FIGURE 11) be formed with a conventional turned welt 140 which is preferably knit of a textured nylon multifilament yarn of about 40 denier to provide some stretchability to the fabric. The turned welt is preferably knit in a two-feed manner, after the make-up courses are formed in a conventional manner and the stitch loops are held on the transfer points of the dial, not shown, until they are transferred back to the cylinder needles to form the turned welt portion. During this conventional knitting on all of the needles at each knitting station 10, 11, in the formation of the welt 140, it is preferred that the sinker cam 70 (FIGURE 2) be moved to the dotted line position so that the yarn is knit in front of the nibs 58 of the sinkers 56 at both knitting stations. The bunter screw 121 is positioned against the vertical leg 122 of the support bracket so that the sinker cap 62 is in the normal position and the sinkers 56 move inwardly at both the main knitting station 10 and the auxiliary knitting station 11 to form normal size stitchesover the ledges 60.
During the knitting of the welt portion 140, the stitch size is regulated in a conventional manner and the stitches are of uniform size throughout the welt 140, the short shadow or after welt 141, and the run-stop guard 142. The stitch earns 13 and 40 (FIGURE 1) are adjusted to form the same size stitch at each knitting station 10, 11 during the plain knitting of these parts of the stocking. It should be noted that in knitting a stocking according to the method of the present invention, it is not necessary to change the relative positions of the stitch earns 13, 40 to obtain the desired variation in stitch length, since the stitch length is varied by other means.
As the knitting of the leg portion, broadly indicated at 145 in FIGURE 11, begins, the covered spandex yarn E is introduced to the needles by lowering the special yarn feed finger into the operative position shown in FIG- URE 7 just prior to raising the yarn feed finger 43 which has been feeding the regular nylon multifilament yarn. With the introduction of the covered spandex yarn E at the auxiliary knitting station 11, the nylon body yarn Y is introduced at the main knitting station 10. This nylon body yarn Y is preferably 20 denier monofilament nylon 66.
The sinker cam 70 is moved to the solid line position shown in FIGURE 2 so that the sinkers 56 do not retract or move outwardly at the auxiliary knitting station 11. The bell crank is moved to the operative position shown in FIGURE 4 to thereby shift the sinker cap in a clockwise direction a distance of about one-sixteenth of an inch so that the sinkers 56 are moved inwardly at the main knitting station 10 earlier than normal and thereby cause longer stitches to the drawn at the main knitting station 10 than the stitches drawn at the auxiliary knitting station 11.
The needle lowering cam 104 is. also moved inwardly to the operative position shown in FIGURE 1 and the selector levers 51 operate to cause alternate needles 12 to be raised to take and knit the covered spandex yarn E at the auxiliary knitting station 11 during alternate rotations of the needle cylinder and, during intervening rotations of the needle cylinder, intervening needles 12 are raised to take and knit the covered spandex yarn E. The needles which do not raise and take the elastic yarn remain in a lower position and are dranw by the cam 104 so that the elastic yarn E is floated inside these needles, in a positive manner. The leg portion 145 is knit with the machine set in this manner so that a course of body yarn Y is knit on every needle and a course of covered spandex yarn E is knit on every other needle with each rotation of the needle cylinder. i.
As shown in FIGURE 13, the body yarn Y is knit in every wale W-1 through W- of courses C-2, C-4 and C-6. The covered spandex yarn E is knit in wales W-2, W-4 of courses C-1 and C-5 and floated across wales W-1, W-3 and W-S. The yarn Ejs knit in wales W-l, W-3 and W-5 of courses C-3 and C-7 and floated across wales W-2 and W-4. Thus, in alternate elastic courses, the yarn E is knit on alternate needles and during intervening elastic courses, the yarn E is knit on intervening needles so that the wales in which the elastic yarn is knit are staggered throughout the knitting of at least the leg portion 145.
A schematic illustration of this method of knitting of the body yarn in every wale and the staggered knitting and floating of the elastic yarn is illustrated in FIGURE 17 of the aforementioned York et al. Patent No. 3,250,092. This figure illustrates the manner in which the fabric would appear if it were knit entirely of non-elastic yarn; however, the elastic yarn does not retain the definite stitch loop configuration but tends to straighten out when the fabric is relaxed so that the fabric has substantially the appearance shown in FIGURE 13.
In the stocking of the present invention, the yarn E follows a more sinuous path in the fabric (FIGURE 13) than the elastic yarn in the fabric illustrated in FIGURE 18 of the York et al. patent. This more sinuous path of the elastic yarn in the fabric of the present invention is partly caused by the greater amount of tension applied to the elastic yarn E, about grams, and due to the fact that a greater length of body yarn Y is incorporated in the fabric by the increased length of stitch caused by the early inward movement of the sinkers at the main knitting station. These factors cause alternate stitch loops of the body yarn to take on different shapes. As shown in FIGURE 13, narrow body yarn stitches alternate with short wide body yarn stitches in both coursewise and walewise directions to provide a more definite open-mesh appearance.
During the knitting of the upper portion or first segment of the leg portion 145, down to the dash-dot line 146 (FIGURE 11), the stitch loops are maintained the same size from course to course so that the stocking blank is of substantially the same diameter down to the line 146. During the knitting of this first portion, the stitch size is regulated from the regular size drum of the machine, not shown, and in the conventional manner.
As the next section of the leg is knit, between the dashdot line 146 and the dash-dot line 147 (FIGURE 11), the size of the stitch loops is gradually decreased at both knitting stations by means of the graduating cam 92 (FIGURE 5) and during this time the position of the needle cylinder is controlled by the graduating arm 90. Because of the shape of the graduating cam 92, and the step-by-step movement imparted thereto by the racking lever 95, the stitch loop size is gradually decreased to thereby reduce the diameter of the stocking blank. This section of the leg, between the dash-dot lines 146, 147, is adapted to engage the area of the knee of the wearer.
The medial section of the leg of the stocking, between the dash-dot lines 147 and 148 (FIGURE 11) is preferably knit with the same size stitch loops from course to course. In accordance with the present invention, the stepby-step movement of the graduating cam 92 (FIGURE 5) is interrupted as the control pin 137 moves into engagement with the roller 138 to lift the free end of the racking lever out of racking engagement with the teeth on the rack wheel 93. After the stocking has been knit down to the line 148 (FIGURE 11), the pattern drum 84 is moved a suflicient distance to release the racking lever '95 so that it will again engage the rack wheel 93 and impart step-by-step movement to the graduating cam 92 so that the size of the stitch loops being knit at each knitting station 10, 11 is again gradually reduced by a gradual lowering of the needle cylinder 54. This gradual reduction in stitch size is continued throughout the remainder of the leg portion and down to the dash-dot line 149.
At this dash-dot line 149, the needles which knit the instep portion of the stocking are raised to inoperative position by the usual switch cams 23, 24 and a heel pocket 150 is knit in a conventional single-feed manner, at the main knitting station 10. The heel pocket 150 is knit by feeding a suitable heaver yarn to the needles, such as a 40 denier texture multifilament nylon yarn. The heel pocket is knit in the usual manner by narrowing and widening while the stitch loops across the instep are held on their idle needles.
Upon completion of the knitting of the heel pocket 150, rotary knitting is resumed and the foot portion, broadly indicated at 151, is then knit with the same stitch construction as the leg 145 and in a two-feed manner. It is preferred that the stitch loop size remain constan in knitting the foot portion 151, and the regulation of the stitch size is then under control of the conventional size drum, not shown. After the desired length has been knit in the foot portion 151, a run-stop band 152 is knit in the conventional manner. The toe pocket 153 is then knit in a single-feed manner and of a heavier yarn. The toe pocket 153 may be formed in any desired manner, and in the present instance, it is formed by knitting a single narrowed section and a plurality of loopers rounds or courses 154 are knit to complete the stocking blank.
The manner in which the stocking blank is fashioned during knitting by varying the stitch size in the manner just described provdes a better fit and a more eflicient compressive force on the leg of the wearer after the stocking has been looped or the toe closed by any suitable means. It is preferred that the toe be closed by a curved seam, as indicated at 155 in FIGURE 12, and the shape is set in the stocking after it is boarded and finished in the usual manner.
Thus, by knitting the support stocking in the manner described, the elastic yarn E is fed under substantial tension to the selected needles and positively floated inside the non-selected needles because of the wide separation between the levels of the hooks of the selected needles and those which are not selected, this wide separation being accomplished by means of the special needle lowering cam 104 (FIGURE 1). This special cam 104 insures the positive floating of the elastic yarn and it is virtually impossible to knit the elastic yarn on needles where it should float.
By knitting the elastic yarn E over the ledges 59 and behind the nibs 58 of the sinkers 56 (FIGURE 9) at the auxiliary knitting station 11, the sinkers are not withdrawn and again inserted in the usual manner so that the nibs 58 of the sinkers remain against and maintain tension on the stitch loops of the body yarn course which was previously knit at the main knitting station 10. Thus, the sinkers operate to main tain the fabric under tension at the auxiliary kntting station 11 independently of the usual fabric tensioning means of the machine, usually suction. Therefore, the uniformity of the knit fabric is not dependent upon effective suction or tension being applied to the knit fabric.
Also, by drawing longer or looser stitches of the body yarn at the main knitting station 10, by means of the sinker advancing means and the sinker cap retarding mechanism, a greater length of body yarn is incorporated in the stocking and a relatively lesser length of the covered elastic yarn E is incorporated in the stocking, so that there is more of the 20 denier monofilament body yarn present in the stocking to provide a more sheer appearance to the stocking. Since the elastic yarn E is fed under an abnormally high tension, about 10 grams, the needle cylinder is initially raised to a higher position at the beginning of the knitting of the leg porton 145, to draw long stitches at both the main and the auxiliary knitting stations so that the length of body yarn incorporated in the stocking is substantially greater than normal. This method also allows a greater relative reduction of the stitch size, down to a very small stitch at the ankle, and maintains the proper length of the elastic yarn to the body yarn throughout the knitting of the complete stocking, whether the stitch size is being gradually reduced or is maintained the same.
The high tension applied to the elastic yarn increases the importance of the special feed finger 100 so that the yarn does not rub against the metal throat plate 44 and cause variations in tension and damage to the elastic yarn. With alternate straight and graduated sections in the leg portion of the stocking blank, as shown in FIGURE 11, a gradually upwardly decreasing compressive force is applied to the leg of the wearer. Thus, the upper portion of the leg is not constricted by the stocking and the compressive force is greatest at the ankle and gradually reduces up the leg so that the pressure on the veins in the leg is gradually reduced from the angle upwardly, thereby gently forcing the blood back up the leg of, the wearer.
In the drawings and specification there has been set forth a preferred embodiment of the invention and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.
1. A method of knitting an elastic support stocking, with at least the leg portion having an open mesh and highly sheer appearance and gradually upwardly decreasing compressive efiect, on a multi-feed circular knitting machine having stitch forming instrumentalities, including a circle of needles, and sinkers supported for radial movement between the needles and having nibs with stitch drawing ledges in front of and behind the nibs, which method comprises the steps of (a) feeding under a substantially small tension an inelastic yarn to all the needles at one yarn feed and lowering the needles to draw the inelastic yarn down in front of the nibs of the sinkers and advancing the sinkers at an earlier than normal position to form said inelastic yarn into knitted stitches of a selected, relatively large size,
(b) feeding under a relatively high tension an elastic yarn to alternate needles and floating the elastic yarn above intervening needles at the next successive yarn feed and maintaining the sinkers in the innermost position while lowering the alternate needles to draw the elastic yarn down behind the nibs of the sinkers and form said elastic yarn into knitted stitches of a substantiallysmaller size than said inelastic yarn stitches, and
(c) repeating steps (a) and (b) throughout the knitting of at least the leg portion, the knitting and floating of said elastic yarn being staggered between alternate and intervening wales from course to course, the relatively high tension on said elastic yarn reducing the amount of elastic yarn in the stocking and the relatively large size stitches of said inelastic yarn increasing the relative length of inelastic yarn in the stocking to thereby enhance the sheer appearance of the stocking.
2. A method according to claim 1, wherein the elastic yarn is fed under a tension of about 10 grams in step (b).
3. A method according to claim 1, wherein the elastic support stocking includes a turned welt at the upper end and a heel pocket at the lower end of the leg, and wherein the method includes maintaining the stitch size constant at both knitting stations and throughout the knitting of the portion of the leg immediately below the welt, gradually reducing the stitch size at both knitting stations throughout the knitting of the next adjacent portion of the leg, maintaining the stitch size constant at both knitting stations throughout the knitting of the next adjacent medial portion of the leg, and gradually reducing the stitch size at both knitting stationsthroughout the knitting of the next adjacent remaining portion of the leg, down to the heel pocket.
4. A method according to claim 1, wherein the'multifeed machine includes a main. knitting station and an auxiliary knitting station, the inelastic yarn being fed at the main knitting station and the elastic yarn being fed at the auxiliary knitting station to form a course of elastic yarn and a course of inelastic yarn with each rotation of the needle circle, selective needle raising means in advance of said auxiliary knitting station, and a needle lowering cam at said auxiliary knitting station and being operable to engage and lower the needles not raised by said selective needle raising means to provide a relatively wide separation between the raised and lowered needles at the auxiliary knitting station, said method including the steps of feeding the elastic yarn at a predetermined level at the auxiliary station, raising alternate needles sufficiently to pick up the elastic yarn while lowering the intervening needles well below the elastic yarn feeding level to cause a positive floating of the elastic yarn at the intervening needles during alternate rotations of the needle circle, and raising intervening needles sufiiciently to pick up the elastic yarn while lowering the alternate needles well below the elastic yarn feeding level to cause a positive floating of the elastic yarn at the alternate needles during intervening rotations of the needle circle.
References Cited UNITED STATES PATENTS 2,057,436 10/1936 Lawson 66 -108 2,531,073 11/1950 Miller 66l08 2,913,886 11/1959 Kale et al 66l08 XR 3,054,278 9/ 1962 Haddad 66l08 XR 3,174,306 3/1965 Lawson 66l08 XR 3,250,092 5/1966 York et al 66178 XR 3,372,562 3/1968 Imboden et a1 66l08 FOREIGN PATENTS 1,127,531 4/1962 Germany.
526,280 9/1940 Great Britain. 608,377 9/1948 GreatBritain.
RONALD FELDBAUM, Primary Examiner US. Cl. X.R. 66178