US2913886A

US2913886A - Apparatus and method for knitting elastic fabric

Info

Publication number: US2913886A
Authority: US
Publication date: 1959-11-24
Anticipated expiration: 1976-11-24

Description

R. B. KALE ET AL 2,913,886

Nov. 24, 1959 APPARATUS AND METHOD FOR KNITTING ELASTIC FABRIC 5 Sheets-Sheet 1 Filed Oct. 29, 1957 R|Q+\A\2t B. KALE am NORMAN J. LEMoNs INVENTORS ATTORNEY!) Nov. 24, 1959 A L ET AL APPARATUS AND METHOD FOR KNITTING ELASTIC FABRIC 5 Sheets-Sheet 2 Filed Oct. 29, 1957 ECHAED B. KALE no NORMAN J. LEMO INVENT ATTORNEYS Nov. 24, 1959 KALE ET AL APPARATUS AND METHOD FOR KNITTING ELASTIC FABRIC Filed Oct. 29, 1957 5 Sheets-Sheet 3 RKLHARD- B. KALE- and NORMAN J. LEMoNs INVENTORE ATTORNEYS Nov. 24, 1959 R. B. KALE ETAL APPARATUS AND METHOD FOR KNITTING-ELASTIC FABRIC 5 Sheets-Sheet 4 Filed Oct. 29, 1957 Emu-mm B. KALE- 20d NORMAN 43'. LEMONS INVENTORS BY aim,

ATTORNEYS "R. 5.10m: EI'AI.v 2,913,886 7 APPARATUS AND mom son KNITTING ELASTIC FABRIC Filed 001.; 29, 1957 Nqv. 24, 1959 5 sheets-sheet 5 RIC-HARD B.

NORMAN 3'. 7 F1 g=9 I INVENTORS .wlzz awzgmqwzgu ATTORNEYS United States Patent APPARATUS AND METHOD FOR KNI'ITING ELASTIC FABRIC Richard B. Kale and Norman J. Lemons, Meban'e, N.C., assignors to Kale Knitting Mills, Inc., Mebane, N.C., a corporation of North Carolina Application October 29, 1957, Serial No. 693,096 4 Claims. (21. 66-9) This invention relates to circular knitting machines, and, more especially, to an improved method'and apparatus for producing elastic fabric, such as hosiery.

It is well known that, in ordinary knitting on a circular knitting machine, inelastic yarns or body yarns are fed and the needles are then lowered by conventional stitch. cams to draw stitches over the body portions of the sinkers in forming loops or stitches of normal length. However, in order to produce a highly stretchable circularly knit fabric having a mock ribbed effect, it is necessary to form elongated stitches of a length substantially greater than normal length while laying in or knitting elastic yarn under tension.

It is an object of this invention to provide an improved method and apparatus for making elastic fabric which results in the stitches formed from the inelastic yarn being uniform and nondistorted, to an extent which has not been attainable by prior method to my knowledge.

It is another object of this invention to provide an improved method and apparatus for making elastic fabric of the type having an elastic strand laid in front of cer-' tain spaced stitches and in back of intervening stitches and wherein the elongated stitches are formed'by ac-. celerating the inward movement of the sinkers immedi-- ately following the taking of the body yarn by the needles so that the sinkers are disposed all the way inwardly .at

substantially the same point at which the butts of the needles pass beneath the lowermost point of'the corresponding stitch cam. This causes the yarn to be caught,

in the notches immediately beneath the nibs of the sinkers and to be pulled inwardly toward the center of' the needle cylinder with respect to the upper ends or hooks of the needles before or at substantially the same time as the needles pass beneath the corresponding stitch cam, thus resulting in abnormally long stitches being formed.

It is still another object of this invention to provide novel means for controlling the sinker cap (containing the sinker cams) whereby, during normal knitting, the

sinker cap may occupy either of two predetermined: norexisting circular knitting machines and which apparatus' is applicable to many different types of circular knitting machines.

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- 1 Figure'l is a front elevation of the main portion of a typical solid color pattern circular knitting machine equipped with the novel apparatus of the present invention;

Figure 2 is an enlarged fragmentary plan view, partially in section and with parts broken away, taken substantially along line 22 in Figure 1, showing the sinker cap in the position occupied thereby during normal rotary knitting;

Figure 3 is a view similarto Figure 2 showing the sinker cap in abnormal position, as occupied during the forming of elongated stitches at the main knitting station With the'inner point of the opposite sinker advancing cam disposed in substantially vertical alinement with the 1owermost point of the corresponding-main stitch cam;

Figure 4 is an enlarged fragmentary view similar to the right-hand upper portion of Figure 2, showing associated sinkers and needles with a fabric portion having normal stitches suspended therefrom;

Figure 5 is a view similar to Figure 4 in which the sinker cap occupies said abnormal position and showing a portion of fabric with elongated stitches formed thereon;

Figure 6 is a diagrammatic view showing needle and jack cams and illustrating the paths followed by the needles during rotary knitting, according to the present method;

Figure 7 is a greatly enlarged view of a typical fabric as made on the present machine;

Figure. 8' is a fragmentary vertical sectional view showing a portion of the needle cylinder, sinker head and sinker cap, and wherein the sinker cap occupies the position of Figure 2 for forming stitches of normal length;

Figure 9 is aview similarto Figure 8, but wherein the sinker cap has beenshifted to the position of Figure 3 for forming elongated stitches;

Figures 10 and 11 are schematic views showing two different types of cams which may be used on the main pattern drum wherein Figure 10 shows a cam used for controlling the sinker cap during the forming of elongated stitches of uniform length, and wherein Figure 11 showsa similar cam which may be used for fashioning the leg of a stocking during knitting thereof.

The present invention is shown in association with a solid color pattern knitting machine of a type such as is disclosed in U.S. Patent No. 2,217,022 which is commonly known as a- Hemphill SCP knitting machine. However, it is to be distinctly understood that the principles of the present invention may be readily applied to many different types of circular knitting machines, and the particular knitting machine is shown in the accom-j I panying drawings by Way of illustration only.

Since the machine disclosed herein is of substantially the type disclosed in said Patent No. 2,217,022, only so much of the machine will be described as is necessary to a clear understanding of the present invention.

Referring more specifically to the drawings, the knitting machine comprises a frame broadly designated at 20, whose lower portion has usual driving mechanism therein, not shown, for imparting reciprocatory and rotary motion to a needle cylinder 21 according to the desired pattern. The needle cylinder is supported on a bed plate 22, which also supports a stationary cam plate 23 on which conventional needle cams are mounted. In this instance, the knitting cams include two knitting stations,

namely, a main, right hand or first knitting station broadly therein. A selector jack '1 is positioned beneath each. needle N (Figure 6). As is usual, substantially half of" the needles are provided with long butts and the re maining half of the needles are provided with short butts to facilitate separating the active and inactive needles in the reciprocatosy knitting of the heel and toe of a stocking. The pertinent cams for controlling the needles N and the jacks] will 'be later described.

The machine also comprises a conventional sinker head 30 which surrounds and moves with the upper portionof the needle cylinder 21, and in which conventional sinkers, broadly designated at 31, are mounted for radial movement (Figures 8 and 9).. A sinker cap 32 surrounds the upper portion of and overlies the sinker head 30 and has conventional sinker cams therein (Figures 2, 3, 4 and for controlling movement of the sinkers 31.

Although the present method is carried out by controlling the position of the sinker cap and its cams in a novel manner, special sinker control cams. need not necessarily beemployed. In other words, the cams in the sinker cap may be conventional. In this instance, the underside of the sinker cap 32 is provided with a raceway against which the outer surfaces of butts 33 of the sinkers 31 move with rotation of the needle cylinder 21 and sinker head 30.

Said raceway is formed by a pair of rear and front

segmental sinker cams

34, 35 depending from the sinker cap 32 and which have respective pairs of

sinker advancing cams

36, 36a and 37, 37a at their opposite ends. The sinker advancing cams are provided with inclined o r angular

free end surfaces

38, 38a, 39, 39a which form respective inner points or apexes P, P-1, P-2, P-3 thereon. The proximal ends of the

earns

36, 37a and 36a, 37 define

respective recesses

40, 40a in the sinker cap 32. The sinkers 31 are moved into these recesses by respective sinker withdrawing or retracting

cams

41, 41a. The

sinker withdrawing cams

41, 41a are disposed above the respective sets of knitting

cams

25, 26 at opposite sides of the machine and immediately below respective main and auxiliary body

yarn feed stations

42, 43 so as to give the sinkers 31- their outward radial thrust above the knitting cams.

The

sinker advancing cams

36a, 37a return the sinkers inwardly to advanced position after they are projected outwardly by the respective withdrawing

cams

41, 41a with clockwise movement of the needle cylinder. On the other hand, the

sinker advancing cams

36, 37 move the sinkers inwardly to advanced position after they have been moved inwardly by the respective

sinker withdrawing cams

41, 41a during counterclockwise movement' of the needle cylinder 21. Actually, during the knitting of elongated stitches according to our method, only-the sinker advancing cam 36 need be considered, since; it is the movement of the sinker cap according to thisinvention, with consequent variation as to the positionof the sinker advancing cam 36 relative to the main knitting station 25, which determines the'size of the stitches being formed.

With this in mind, it should be ,noted that the free end 38 of the sinker advancing cam 36 is preferably formed at a steeper than normal angle with respect to the-path of travel of the butts 33 ofthe sinkers 31, as manifested by the angularity of the

freeends

38a, 39a o f the-respective sinker advancing cams 37a relative to the sinker advancing cam 36. However, the point or apex- P of the cam 36 correspondsv substantially to the apexesor points P-1, P-3 ofthe

sinker advancing cams

36a, 37a; that is, the apex or point P of cam 36 occupies its usual position with respect to the sinker cap 32. The reason for the relatively steeper angular form of the freeend of cam 36 will be given laterin this context.

Therear portion of the sinker cap32 has the usual spaced

adjustable abutments

45, 46 mounted thereon which. are adapted to ultimately engage a fixed stop member 47 duringreciprocation of the needle cylinder 21. As .is. well known, the sinkers 31-normally cause the sinker-cap-32 .to occupy a'position with theabutment 45 in engagement with the stop member 47, S 1b$,tantially,

as shown in Figure 2, with counterclockwise movement of the needle cylinder 21. Of course, with clockwise movement of the needle cylinder, the sinkers cause the sinker cap to normally occupy a position in which the abutment 46 is in engagement with the stop member 47. Either of the latter positions may be termed as a normal position.

Spaced closely above the sinker cap 32 is a conventional latch ring 50 formed with a pair of

throats

52, 53 in which respective sets of conventional inelastic, body yarn or main

yarn feed fingers

54, 55 are positioned to form the

yarn feed stations

42, 43. The

yarn feed fingers

54, 55 are controlled and operated in a conventional manner for feeding respective body yarns or inelastic yarns Y, Y to needles N when any of such fingers are in lowered or operative position.

Referring to Figure 6, the various needle and jack cams which encircle the needle cylinder are only shown diagrammatically since they are identical to and may be operated in substantially the manner disclosed in said US. Patent 2,217,022. The main and

auxiliary knitting stations

25, 26 include respective pairs of stitch cams 60, 61, a, 61a and respective

top center cams

62, 62a. The auxiliary set of stitch drawing cams 26 includes a wing cam 64 spaced closely above the topcenter cam 62a. In Figure 6, the cams are cut at the center of the auxiliary station and, thus, opposite halves of such cams appear at the extreme ends of the figure. The usual needle raise cams are provided between the main and auxiliary sets of

stitch cams

25, 26, the needle raise cam at the back of the machine being indicated at 65 and the needle raise cam at the front of the machine being indicated at 66. Conventional needle raising switch cams 70, 71 are provided at the front and at the back of the machine. These switch earns 70, 71 are active for engaging the butts of needles during reciprocatory knitting, but remain withdrawn during circular knitting, the present invention being concerned only with circular knitting. As disclosed" in said Patent No. 2,217,022, the stitch cams 60, 61, 60a, 61a are also radially movable between active and inactive positions.

As heretofore stated, the selector jacks I may be of conventional construction and, as shown in Figure 6 a lower portion of each jack J is provided with a master butt 74 which is spaced below an auxiliary or leveling butt 75. A plurality of saw-tooth removable pattern butts 76'are provided between the master butt 74 and the leveling butt 75. The pattern butts 76 may be arranged according to a predetermined pattern, as is well known.

Conventional jack leveling or lowering cams 80, 80a depend from the cam supporting plate 23 below the respective sets of

stitch cams

25, 26, and circularly spaced series of

pattern'controlled selector plungers

81, 82, 81a, 82a areprovided between'the leveling cams 80, 80a at the front and rear of the machine. The bed plate 22 supports jack raising'cam s'83, 84, 83a, 84a which serve to engage the master butts 74 of any jacks I selected by the respective-series'of' selector plungers' 8 1, 82, 81a, 82a to raise these jacks and their needles'to where such needles will take yarn from the next succeeding yarn feeding finger then in active' or lowered position.

An elastic yarn-feed finger 85 is'provided which may be shifted'into' and out of active position with respect to the needles as is well known in the art, a suitable means for'this purpose being illustrated in US. Patent No. 2,716,876. Sincethe'elastic yarn feed finger 85 may be controlled and operated by means well known in the art, adetailed illustration and description thereof is deemed unnecessary. The elastic yarn feed finger 85 may occupy active position at practically any point inwardly of and closely adjacent the latch ring 50, for feeding yarn to' selected needles. However, since the sinker'cap. 32 is provided with a conventional sinker withdrawing cam 41a above the auxiliary knitting station 26, audit is.desirable-to-withdraw the sinkers after the ure 6, in advance of and closely adjacent the auxiliaryyarn feed station 43 so that needles above any jacks I selected by the series of selector plungers 82a will take yarn from the elastic yarn feed finger 85 as the latter jacks are elevated by the jack raising cam 84a.

Referring to Figure 1, the knitting machine is equipped with a main pattern drum 87 having segmental cams 88 thereon which engage the lower ends of conventional thrust rods 89 for controlling various conventional ele ments of the knitting machine.

Now, as heretofore stated, in order to form elongated stitches according to the present method, the sinker cap 32 is controlled so as to occupy an abnormal position intermediate either of said normal positions; that is, both of the

abutments

45, 46 are maintained in spaced relation astraddle the stop member 47. While the sinker cap 32 occupies the latter position, the apex P (Figures 2 and 3) of the sinker advancing cam 37 is positioned'in substantially the same vertical plane as the lowermost: point or surface of the left hand stitch cam 61 at the main knitting station 25. Generally, the needle cylinder 21 is rotating, or will have last rotated, in a counterclockwise direction in Figures 2 and 3 prior to the sinker cap 32 being moved to said abnormal position. Accordingly, it can be said that the sinker cap 32 is shifted from normal to abnormal position ina clockwise direction or in a direction opposite from that in which the needle cylinder 21 is rotating or had last rotated, to increase the amount of yarn drawn through each needle prior to a stitch being formed therewith and to thereby form elongated stitches.

In Figure 1, there is shown a preferred embodiment of control means for shifting the sinker advancing cams and sinker cap 32 to said abnormal position, or for limiting counterclockwise movement of the sinker cap 32 to an intermediate or abnormal position in the event that it is moved by rotation of the sinkers and sinker head. Said sinker cap control means comprises a.movable finger or lever 90 whose lower portion is movable to and fro under control of the pattern drum 87. During the knitting of stitches of normal length, the finger 90 occupies inactive position, substantially as shown in Figures 1 and 2, during which it may or may not be in engagement with an abutment 91 carried by and projecting forwardly from the sinker cap 32. The finger or lever 90 extends upwardly in Figure land is pivotally mounted, as at 93, on the front surface of the latch ring 50. The upper portion of the finger or lever 90 has one end of a link 94 pivotally connected thereto which extends outwardly and is pivotally connected to one arm of a bell crank 95.

The bell crank 95 is oscillatably mounted, at the juncture of its arms, on a post 96 which is a conventional part of the frame 20 and is supported by the bed plate 22. The other arm of bell crank 95 has the upper end of a connecting rod or link 97 pivotally connected thereto which extends downwardly and freely extends through a suitable opening, not shown, in the bed plate 22. The lower end of the link or connecting rod 97 is pivotally connected, for longitudinal adjustment, toone end of a lever 100 which is oscillatably mounted intermediate its ends, as at 101, on a fixed part of the frame. The end of the lever 100 opposite from the connecting rod 97 is pivotally connected to the upper end of a special thrust rod 102 provided in addition to the conventional thrust rods 89. i

It will be observed in Figure 1 that the lower portions of the conventional thrust rods 89 and the special thrust rod 102 are guided for vertical movement in a conven: tional slotted guide 103 suitably supported by theframe 20 and spaced above the pattern drum 87. Referring to Figure 10, it will be observed that the pattern drum 87 is provided with at least one segmental cam 105 thereon which, with the exception of its leading end, is

of substantially the same height throughout its length. It is apparent, therefore, that movement of the cam 105 into engagement with the lower end of thrust rod 102 imparts upward movement to the same and, in turn, imparts clockwise movement to the finger 90 in Figure 1 to move the same from substantially the position shown in Figure 2 to that shown in Figure 3. Assuming that the sinker cap 32 normally occupies the position shown in Figure 2, it is apparent that clockwise movement of the finger in Figure 1, or from right to left in Figure 2, moves the sinker cap 32 in a clockwise direction from said normal to said abnormal position. As will be more fully described hereinafter, this causes the sinkers 31 to be advanced more rapidly than normal to thus cause the needles to take excessive yarn in the hooks thereof and subsequently form relatively long or elongated stitches. The body yarn Y is preferably fed under relatively light tension during the knitting of the elongated stitches.

Now, in some instances, it may be desirable to form stitches of controlled size varying between maximum and minimum, such as in fashioning the ankle portion or leg of a stocking. To this end, a modified form of sinker cap controlling cam 106 is shown in Figure 11, the latter cam also being fixed on the pattern drum 87. It will be noted that the cam 106 is tapered and varies in height throughout a portion, at least, of its length. It is apparent, therefore, that the cam 106 will cause gradual movement of the. sinker cap 32 between the positions shown in Figures 2 and 3 with corresponding gradual variation in the length of stitches formed. This obviates the necessity of raising and lowering the needle cylinder for forming stitches of varying size in the leg of a stocking, for example, and facilitates more accurate control of the length of the stitches than has been the case heretofore.

In Figures 2 and 4, the sinker cap 32 is shown in normal position as occupied during counterclockwise movement of the needle cylinder. It will be noted that these Figures 2 and 4 have two radially extending broken lines thereon, one of which is indicated at A and the other of which is indicated at B. The broken line A indicates the normal position of the point or apex P of the particular sinker advancing cam 36 which advances the sinkers during counterclockwise movement of the needles past the right-hand knitting station 25. On the other hand, the broken line B in each of the Figures 2 and 4 denotes the position of the lowermost point of the stitch cam 61 relative to the point of the corresponding sinker advancing cam 36 during the knitting of normal stitches. The broken line C represents the center line of the

yarn feed stations

42, 43. Thus, it is apparent that the sinkers move inwardly to maximum inward position after the stitches have been drawn by the corresponding needles so that normal size stitches are formed (see Figures 4 and 8).

Now, referring to Figures 3 and 5, there will be ob served a radially extending broken line indicated at AB, which denotes substantially the position of both the lowermost point of the stitch cam 61 at the-main knitting station 25 and the apex P of the adjacent sinker advancing cam 36. It follows, therefore, that upon yarn being taken in the hooks of the needles at the main yarn feed station 42, these needles, as they are moved downwardly by the left-hand stitch cam 61 at the knitting stations 25 in Figure 6 are in the process of drawing stitches at the same time that the adjacent sinkers 31 move inwardly so that, in effect, the sinkers are advanced prior to the corresponding stitches being completed. As a result, it would be observed in Figure 9 that the yarn is drawn through the sinkers and extends at an angle from below the nib 31a of the corresponding sinker 31 before the stitch is drawn through '7 a preceding stitch, with the result that excessive yarn Y is drawn from the source prior to the yarn on the cor-responding needle being drawn through the preceding stitch to form another stitch so that elongated stitches are formed in the fabric as indicated at S-1 in Figure The stitches 8-1 are substantially longer'than the normal length stitches S, as can be readily determined by a comparison of the portions of fabric shown in Figures 4 and 5.

In knitting the portion of fabric shown in Figure 7,, which is typical of many different types of fabric which may be knit according to the present inventior}, a f ill? stitch earns 60, 60a, 61, and 61a of the

twg knitting stations

25, 26 are withdrawn during the'rnakeup. All the

yarn feed fingers

54, 55 at the respective

yarn feed stations

42, 43 also occupy inactive'or raised position and the elastic yarn feed finger 8 5 occupies lowered or operated position. r

Thus, with rotation of the needle cylinder 21 in a counterclockwise direction in Figure 2, pr with-move= ment of the needles and jacks N and J from right to left in Figure 6, spaced jacks or all of the jacks, as desired, are selected by the selector plungers 82a so their master butts 74 ride up the cam 84a. Corresponding needles are elevated to where the hooks there of move on a path 110 to take the elastic'yarn E at the yarn feed finger 85. Several turns of elastic yarn E are taken in the hooks of said raised needles without stitches being drawn to form what may be termed as a multi-ply elastic makeup strand M, which preferably includes four turns of elastic yarn E. It is apparent that this would require four revolutions of the needle cylinder.

At this time, the left-hand stitch cam 60a, at the auxiliary knitting station 26, is moved into operative position, immediately following which the two stitch cams 60, 61 at the main knitting station 25 are also moved into operative position. One or more of the yarn feed fingers 54 at the main yarn feed station 42 are also then lowered into operative position. However, the right-hand stitch cam 61a at the auxiliary knitting station 26 remains withdrawn or in inactive position.

As the aforementioned stitch cams 60, 61, 60a are moved'into operative position, the sinker cap 32 may be shifted from the position shown in Figure 2 to that shown in Figure 3, if desired. However, some customers may prefer that the first few courses, say, four courses knitted from the body yarn Y and in which the elastic yarn is laid, are formed with stitches of normal size. In this instance, the movement of the sinker cap 32 to abnormal position may be delayed until four courses, more or less, have been knitted. Since the number of courses having normal size stitches may vary, or the top of a stocking, for example, maybe entirely formed with elongated stitches, it shall be assumed, for purposes of description, that the sinker cap 32 is moved from the position of Figure 2 to that of Figure 3 substantially simultaneously with movement of the stitch cams 60, 61 at the main knitting station 25' into operative position.

Although the auxiliary stitch cam 60a moves into operative position to engage the butts of needles having elastic yarn E in the hooks thereof, it will be noted that the cam 84a in the left-hand lower portion of Figure 6 is of such height that the latches of the corresponding needles do not clear the elastic yarn held in the hooks of the needles so that, as the butts of the needles subsequently pass beneath the left-hand auxiliary stitch cam 69a along a path 111, they merely pull the elastic downwardly between adjacent sinkers without forming stitches. After each successive needle passes the auxiliary stitch cam 60a, alternate needles, or certain spaced needles, are selected through the medium of the corresponding jacks I and selector plunger 82, so that th s a d n e le a e e e ates a P th 11. yt hthand stitch cam at the main knitting station 25 to where tjhelatches thereof'clea'r the elastic'yarn previously deposited in the hooks thereo and then take body yarn Y in the hooks the r eof'and draw stitches as 'they are lowered by th e main left hand stitch cam 61. While said spaced or alternate needles are taking the body yarn Y and foriniug stitches therewith fth e intervening needles retain the elastic yarh in the hooks thereof, since they pass beneath the stitch cams 60, 61.

After ne'edles pass the le ft-h and stitch cam 61 with movement from right to left, in Figure 6, alternate or spaced needles, preferably every fourth needle, are selected through the medium of the corresponding jacks I and the series of selector plungers 82a so that they pass upwardly outside of the previously formed stitches to take the elastic yarn from the yarn feed finger 85 so the elastic yarn is laid in front of some of the needles, or said every fourth needle, and is laid in back of the other or intervening needles. I i I Since the sinkers are withdrawn at the auxiliary station by the sinker withdrawing cam 4111 (Figures 2 and 3) the elastic yarn is laid on the tops of the ledges of the sinkers and beneath'the nibs, as the butts of needies subsequently pass beneath the left-hand auxiliary stitch cam 60a. At this time, the sinkers are moved inwardly or advanced by the sinker advancing cam 36a so as to hold down the elastic yarn when all the needles are subsequently selected and raised to form the first course following the makeup at the main knitting station 25.

It is apparent that the fabric has been formed as shown in Figure 7 with elastic yarn laid or floated in back of or on the inside of the groups of three stitches formed by those needles which do not take the elastic yarn. Every fourth stitch formed from the body yarn in the fabric is also disposed outside ofthe elastic yarn, but the elastic yarn passes between the groups of three stitches and the intervening'fourth stitch to extend in front of the bights of the sinker loops between the spaced groups of'three stitches and the intervening single wale of stitches. After the desired number of courses have been formed with the elongated stitches in the manner heretofore described, the sinker cap may then be returned to the normal position by releasing the finger 90. Stitches of normal size may then be knit to form any desired patterning as is customary depending upon the type of machine with which the present apparatus is used.

As has already been described, the front end 38 of the sinker advancing cam 36 preferably extends at a relatively steep'angle as compared to corresponding surfaces of the

cams

36a and 37a. While this is not absolutely necessary, it insures that the inward movement of the sinkers'does not take affect before the body yarnY. from the main yarn feed station'42 hasengaged the ledges of the adjacent sinkers 31. It is apparent that the provision of the relatively steeper angular surface on the front end of the sinker advancing cam 36 would depend upon the particular type of sinkers employed. and, in particular, upon the amount that the nibs 31a of the sinkers 31 project inwardly over the ledges.

Due to the fact that the sinker cap 32 occupies said abnormal position during the knitting of elongated stitches, it is also preferred that therear end 39 of the auxiliary sinker advancing cam 37 is cut away, in a manner similar to that described with respect to the front end 38 of the cam 36, to further insure that the sinkers remain withdrawn to a point sufficiently beyond the point at the elastic yarn E is fed to needles by'the yarn feed finger 85' so the elastic yarn will subsequently be engaged beneath the nibs of the'sinkers advancedbythe'cam 31, I i

In the drawings and specification there has been set forth a'preferred embodiment of the inventio riand, although specific term s'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.

We claim:

1. A method of knitting a stocking on a circular independent needle knitting machine which comprises raising spaced needles and leaving intervening needles lowered, feeding an elastic strand to the raised needles to cause the strand to be engaged by the hooks of said raised needles, advancing sinkers to hold the elastic strand beneath the nibs of the sinker then raising all of the needles disposed between the inwardly advanced sinkers to cause the elastic strand to be deposited on the backs of said spaced needles, then withdrawing the sinkers outwardly while feeding at least one body yarn to the needles at the point where the sinkers are moved outwardly, then advancing the sinkers inwardly with their nibs over the yarn in timed relation to lowering the needles to a position to complete the formation of stitches therewith and such that the sinkers reach fully inward position at substantially the instant the needles reach said stitch completing position whereby a substantial amount of yarn is drawn through the needles prior to stitches being formed on the last-named needles to form elongated stitches from the body yarn over the ledges of the sinkers while the elastic strand is confined below the nibs of the sinkers.

2. A method of knitting a stocking on a circular independent needle knitting machine which comprises raising spaced needles and leaving intervening needles lowered, feeding an elastic strand to the raised needles to cause the strand to be engaged by the hooks of said raised needles, advancing sinkers to hold the elastic strand beneath the nibs of the sinker then raising all the needles disposed between the inwardly advanced sinkers to cause the elastic strand to be deposited on the back of said spaced needles, then withdrawing the sinkers outwardly while feeding at least one body yarn to the needles at the point where the sinkers are moved outwardly, then advancing the sinkers inwardly, with the yarn beneath the sinker nibs, prior to the needles reaching lowermost position following the drawing of stitches therewith and to where stitches are formed with the needles by a substantial amount of yarn being drawn through the books of needles prior to the stitches being formed on the lastnamed needles to form elongated stitches from the body yarn over the ledges of the sinkers while the elastic strand is confined below the nibs of the sinkers, and to cause the needles to shed the previous body yarn loops.

3. A knitting machine having a circular series of independent needles, at least one stitch cam, means for feeding yarn to the needles, a sinker cap, means for withdrawing the sinkers at said yarn feeding means, a sinker advancing cam carried by the sinker cap for normally advancing sinkers to fully advanced position following movement of the needles beyond the lowermost point of the stitch cam, means for shifting said sinker cap to an intermediate position in which said advancing cam is so positioned as to advance corresponding sinkers to substantially fully advanced position at the point at which the lowermost point of the stitch cam is located while maintaining the yarn last fed to the needles beneath their nibs upon the ledges of the corresponding sinkers, said means for shifting the sinker cap comprising a movable finger located adjacent said sinker cap, means on the sinker cap engageable by said finger, pattern controlled means for moving said finger in engagement with said means on the sinker cap to thereby shift said sinker cap comprising a pattern drum, a thrust rod, linkage connecting said rod to said finger, and at least one segmental cam of substantially uniform height on said drum engageable with said thrust rod.

4. A knitting machine having a circular series of independent needles, at least one stitch cam, means for feeding yarn to the needles, a sinker cap, means for withdrawing the sinkers at said yarn feeding means, a sinker advancing cam carried by the sinker cap for normally advancing sinkers to fully advanced position following movement of the needles beyond the lowermost point of the stitch cam, means for shifting said sinker cap to an intermediate position in which said advancing cam is so positioned as to advance corresponding sinkers to substantially fully advanced position at the point at which the lowermost point of the stitch cam is located while maintaining the yarn last fed to the needles beneath their nibs upon the ledges of the corresponding sinkers, said means for shifting the sinker cap comprising a movable finger located adjacent said sinker cap, means on the sinker cap engageable by said finger, pattern controlled means for moving said finger in engagement with said means on the sinker cap to thereby shift said sinker cap comprising a pattern drum, a thrust rod, linkage connecting said rod to said finger, and at least one segmental cam on said drum engageable with said thrust rod, said segmental cam being of varying height throughout at least a portion of its length.

References Cited in the file of this patent UNITED STATES PATENTS 1,890,880 Lawson Dec. 13, 1932 2,057,436 Lawson Oct. 13, 1936 2,420,771 Crawford et al. May 20, 1947 2,617,282 Reichert Nov. 11, 1952