US3124945A - Moretta - Google Patents

Description

G. MORETTA March 1 7,l 1964 TWO FEED CIRCULAR KNITTING MACHINE AND METHOD Filed May 22, 1956 4 Sheets-Sheet 2 INVENTOR. 601561995 045771 Mm.. ruwe? March 17, l1964 G. MoRETTA TWO FEED CIRCULAR KNITTING MACHINE AND METHOD 4 Sheets-Sheet 3 Filed May 22, 1956 INVENTOR. 6m; fm? www BY W fmt/vtr March 17, 1964 G. MORETTA Two FEED CIRCULAR KNITTING MACHINE AND METHOD Filed May 22, 1956 4 Sheets-Sheet 4 INVENTOR. @arse-PPF 70er? 7W BY if roem? a' United States Patent O 3,124,945 TWG FEED CHRCULAR KNITTING MACHINE AND METHD Giuseppe Moretta, Via Sienne, 5, Varese, Italy Filed May 22, 1956, Ser. No. 586,43@ Claims priority, application Italy Nov. 14, 1955 6 Claims. (Ci. 645-42) The present invention relates to a two-feed circular knitting machine for stockings and hosiery of the kind provided with ya rotary needle cylinder `and fixed needle lactuating cams.

In particular, the invention relates to a circular knitting machine for manufacturing fancy pattern ladies stockings, viz. stockings Whose knitted fabric is not constituted exclusively by plain loops, but shows a certain predetermined design. The design may he obtained as is known by having certain preselected needles retain the formed stitch for `discharge or release only, together with the subsequent stitch formed by the same needle, in such `a manner as to create elongated loops in the retained stitches. In this way it is possible to form a knitted fabric having the appearance of a tiny net and this kind of fabric is commonly called net fabric.

To obtain a fancy pattern knitted fabric for ladies stockings with satisfactory appearance and general characteristics it is convenient that the fabric should not he formed exclusively -by design courses and it has been found that best conditions are obta-ined with a design formed by `alternating courses having tuck stitches fonmed therein with courses having only plain loops or stitches. In fact the design patterns mostly used with ladies stockings are always constituted by alternated courses with plain loops and with design loops or tuck stitches.

Alpart from this consideration, it :is necessary -to have in design knitted fabric for ladies stockings from time to time a course o-f plain loops or stitches for the simple reason that during the manufacture of the stocking, namely at the end of the heel of the stocking, for reasons that will he explained hereinafter it is necessary to make a course of plain loops. If it is desired to obtain a knitted fabric uniform in all of its parts, which is particularly important in the case of ladies stockings, in which owing to their neness the slightest lack of luniformity of the fabric appears with striking evidence and, therefore, constitutes an inadmissible defect, it is necessary to provide in lthe design a number of courses made Iwith plain loops.

Ladies stockings 4made with a fancy pattern design as set forth hereinbefore were manufactured heretofore on circular knitting machines having only one point of yarn feed, that is, in other words, on single feed circular knitting machines. Those machines are normally equipped with a design device that provides the desired selection of ,needles in such a way :as to obtain the predetermined design. `Operation of those machines and of the design device is wellaknorvn. i

For the manufacture of non-designed ladies stockings (that is to say, of stockings with plain loops), 4as well as of socks and mens wear, there have been created socalled two-feed circular knitting machines, in order to increase production. In fact those machines produce at each turn of the needle cylinder two courses of loops so as to nearly double production.

`Obviously the two-feed system had to be adapted also to circular knitting machines `for the manufacture of fancy pattern ladies stockings.

It would be possible to provide suc-h a tw0-feed machine by providing for each yarn feed a particular design device lZiiS Patented Mar. 17 1964 adapted to select the needles properly before arriving at their respective feeding points. However a structure based on that principle would turn out to be rather cornplicated and costly and, considering the fact that the designs for ladies stockings mostly and commonly used are formed with tuck stitches only in alternate plain courses, it has been proposed .to eliminate the design device lfor the second feed and to p-rovide only one design device connected with the first feed. In that way with the first feed the courses having tuck stitches would he made, while with the second feed, -dispensing with any selecting members, the courses with plain loops or stitches would be made. It is evident that this embodiment would afford considerable advantages not only from the economical point of Iview but also from the constructional point of view. In putting that idea to practice however difficulties have been met and it is the object of the present invention to provide `a circular knitting machine for ladies stockings with a device adapted to eliminate said difficulties and to permit the use of the two-feed system with a single design device coupled 'with the rst feed.

To .make the present invention more fully understood, it will be advisable first of all to indicate the problems that had to be solved.

As is well-known, in two-feed circular knitting machines for gent-lemens socks or for ladies stockings without design, in certain stages of manufacture of the sock or stocking, the second feed is conveniently made inoperative. This occurs, for example, yduring formation of the heel and during formation of the toe of the sock o-r stocking, in which stages alternate rotary movement is imparted lto `the -needle cylinder.

All of the particular devices and mechanisms ythat are necessary `and that make possible the construction of the heel and of the toe of the sock or stocking, are normally associated with `a feed that hereinafter will be called the first feed. This first feed is provided, moreover, as indicated above, with the design device that selects lthe needles for carrying out the formation of the tuck stitches.

tlf it is desired to dispense with a second design device associ ated with the second feed, so as to produce therewith only plain stitches, the stage of formation of the heel of the stocking in a two-feed circular machine Iwould be as follows.

At the time at which the machine is ready to start the alternate movement to make the heel, the last course in the instep is carried out by the second feed and, therefore, it is a course `of plain stitches only.

Then the second feed is made inoperative and at the same time the operation is started of those known means that raise half of Ithe needles that -form the instep, moving such needles upwards and withdrawing them from lthe action `of the cam.

With this operation necessary to start the construction of the heel of the sock or stocking, the loops that form the instep ride on the shanks of the needles underneath the latches. The machine then starts the formation of the heel with an alternate cyilnder movement. As soon as the heel is finished, the needles formerly lifted are returned to operative positions and enter the first feed. For that course the -design device o-f the first feed however remains inoperative and lthe yarn is fed to all of the needles. It is not possible, in the course that immediately fol-lows the completion of the heel, to make a further selection of needles, in that the needles, as a consequence of their being lifted at the for-mation of the beginning of the heel, already have been cleared of the stitch and obviously can no longer retain the stitch. Hence, it will be seen that this course even if produced D by the rst feed, cannot form anything other than plain stitches. The subsequent course then is produced by the second feed which makes only plain stitches and, therefore, it will be seen that, in this stage of the formation of the stocking, there are necessarily three successive courses of plain stitches in the instep portion of the stocking.

If the pattern of the stocking is of the type specified above, viz. constituted by successive courses wherein one with only plain stitches is alternated with pattern forming tuck stitches, at that point of the instep there would appear a disuniformity of design constituted by the three successive courses of plain stitches. Such an irregularity, which in ladies stockings would appear clearly, is not admissible.

To make the design uniform also at that point, it would be necessary, therefore, to pre-arrange -a design having compulsory configuration, in that it ought to involve periodically a section formed by three courses of plain stitches. However a knittted fabric, especially for ladies stockings, of that kind would not be satisfactory because it would have the appearance of being made with rings.

According to the present invention the above inconvenience has been eliminated and the manufacture of ladies stockings has been made possible with a design having alternate courses of plain stitches and of pattern dening tuck stitches on two-feed circular machines provided with a single `design device associated with the first feed.

The problem has been solved according to the invention by providing means adapted to make inoperative the mechanism of the second feed one revolution of the cylinder before the starting of the hl of the stocking in such `a way that the last course made with continuous rotary movement is produced by the first feed with pattern `defining tuck stitches, there being also provided means for making operative again the mechanism of the second feed one revolution of the cylinder after the end of the formation of the heel in such a way that three successive courses, constituting the course formed immediately before production of the heel and the first and second courses formed immediately after the heel has been produced, are all formed by the first feed only.

In the accompanying drawings there `is illustrated merely by way of example one possible embodiment of the control device for the mechanism of the s-econd feed that is operated every time said mechanism has to be made inoperative and in particular in that stage of the knitting operation wherein the machine begins formation of the heel of the stocking.

In the drawings:

FIG. l is a diagrammatical view of a ladys stocking with indication of the courses of loops in the section about the heel;

FG. 2 illustrates diagrammatically and on Ia greatly enlarged scale the interlacing of 4a type of patterned knitted fabric as obtainable with .the machine according to the invention;

FIG. 3 is a diagram adapted to make clear the conguration of the knitted fabric according to FG. 2;

FIG. 4 shows the development of the needle actuating cams of the machine according to the invention;

FIG. 5 a `diagrammatic elevational view of the cylinder of the machine and of part of the control device for the mechanism of the second feed;

FIG. 5a is a detail view of a part of the arrangement shown in FIG. 5;

FIG. `6 is a plan view of the control device of FlG. 5;

FIGURES 7 and 8 are detail plan Views of a portion of the control device in two distinct stages of operation; and

FGURES 9 and l0 are detail elevational views of another portion of said control device as viewed in directions disposed at right angles to each other.

The machine for making ladies stockings, to which the present invention relates and on which the particular control device `for the mechanism of the second feed has been applied, is of ya commonly known type, both as to its construction and its operation.

Of this known machine, only those essential parts have been shown in the drawings, that are indispensable for understanding the invention.

The drawings show clearly the parts of the control device for the mechanism of `the second feed that have been added according to the present invention.

With reference to FIG. l, -a common ladys stocking is there shown constituted by the usual parts, such as the welt 1, the leg 2, the foot 3, the heel 4 and the toe 5.

In FIG. 1 there have been illustrated diagrammatically the courses A to G in the section about the heel 4. Solid lines indicate the courses produced by the tirst feed and broken lines indicate the courses produced by the second fed.

A portion of the same stocking containing the courses A-G is diagrammatically illustrated on a greatly enlarged scale in FIG. 2, While FIG. 3 is a diagram of the corresponding portion of the stocking. From FIGS. 2 and 3, it will be seen that the portion of the stocking there illustra-ted is formed of a knitted fabric having held loops in the courses B, D Iand F and tuck loops in the courses A, C, E and G. The tuck stitch is obtained, in the case illustrated, by having every fourth needle retain the stitch previously formed in s-uch a way as to create elongated loops, for example, at the wales d and h in the courses B and F, and at the wales b and f in the course D.

The tuck loops are normally formed by the rst feed, as indicated by the index l lappended to the letters identifying the various courses in IFIGS. 2 and 3, while the elongated held loops are normally formed by the second feed, as indicated by the index yIl appended to the letters identifying the various courses. Further, in the diagram of FIG. 3, each tuck loop is identified by an X at the pertinent course `and Wale location.

In accordance with the present invention, as illustrated in FIGS. 1, 2 and 3, the three successive courses C, D and E are all formed by the first feed, rather than from the first and second feeds alternately, and the second feed is rendered inoperative during formation of courses C, D and E. Further, it should be noted that the course D, Iwhich lis formed immediately after the heel 4 has been produced, contains elongated held loops and is formed by the lirst feed.

The circular knitting machine of the invention is equipped in conventional manner with all means and mechanisms for the manufacture of ladies stockings and is provided also with a conventional design device coupled to the first feed. The heel and the toe of the stockings are made by the first feed only, which is provided to this end with all members required for such operation.

FIG. 4 illustrates the development of the needle actuating cams that control the movement of the latch needles. In FIG. 4 the cams that control the formation of the loops and of the designs are cross-hatched, while those controlling formation of the heel, of the toe, of the double welt etc. of the stocking are indicated only in profile. Among these cams are included the upper central cam 6, the left sinking cam 7, the right sinking cam 8, the lower central cam 9, the cam l@ for lifting the half of the needles at the beginning of the construction of the heel of the stocking (elimination of the needles forming the instep), and the cam l1 that returns to working position those needles previously lifted by the cam 1d, at the end of the heel formation. All the aforesaid cams belong to the mechanism of the first feed.

The thread-guides for feeding yarn for the rst feed are indicated at 2t) and the inclined cams of the design device for the selection of needles are indicated at 2l. Those inclined cams Z1 are controlled in a known manner by small levers 22 (see FIG. 6) actuated in turn, according to a pre-selected scheme, by the small dowels 23 of the design drum 24. This drum Z4 is controlled from a cam 25 fitted on the main shaft 26 of the machine by means of the lever 27 and pawl 2S.

In FIG. 6 can be seen also the needle cylinder 29 which through the gears 30, 31 and 32 is made to turn at the same rotational speed as the main shaft 26.

The parts and members of the machine as hereinbefore briey described are common in circular knitting machines for ladies stockings and their operation is wellknown to those skilled in the art.

For the second feed, the following members have been added to the conventional machine.

In the assembly of needle actuating cams (FIG. 4), there are added the cam 4t) for the formation of the loops and the bolt 4l for clearing the needles before arriving at the second feed and moreover the thread-guides 4Z for the feed of thread to the second feed.

The control device for the mechanism of the second feed is actuated by the usual control drum 33 of the machine (or by one of the control drums, if the machine is equipped with more than one drum) that governs the movements of all of the members and mechanisms.

It is important according to the present invention that the members of the second feed (cam 4t), bolt 41 and thread-guide 42) in the operative stage of heel formation be rendered inoperative at the right time namely one revolution of the needle cylinder 29 prior to the beginning of the heel and be again rendered operative one revolution of the cylinder 29 after the termination of the heel formation.

For constructive reasons the control drum of the machine can be shifted only once during every four revolutions of the needle cylinder. The angular displacement of the drum from one position to the following one is accomplished in a time having the duration of about two revolutions of the needle cylinder so that the drum, after having arrived at a new angular position, has to remain at standstill in that position at least for the duration of about two revolutions of the cylinder, whereafter it can start a new angular displacement of its own, which also lasts about two revolutions of the cylinder.

This law of movement of the control drum is that normally adopted in known machines; at any rate it is given merely by way of example and it may even vary.

It is important however that for constructional reasons the control drum cannot be practically displaced from one angular position to the following position at every revolution of the needle cylinder.

Since the drum 33 controls all mechanisms of the machine, it is obvious that the members and mechanisms that start operation as well as those that have to be rendered inoperative at the time at which the machine starts and finishes the heel respectively, are also controlled by the same drum. As a consequence, at the time of starting formation of the heel and at the time at which the machine has finished forming the heel, the control drum moves to a new angular position of its own.

Since the control drum, after arriving at a new angular position of its own, can start a subsequent angular movement only after two revolutions of the needle cylinder, it will be seen that ditiiculty is encountered in again putting the mechanism of the second feed in operation after a delay of only one revolution of the needle cylinder following the termination of the heel as required according to the present invention.

On the contrary there are no diiiiculties in rendering inoperative the mechanism of the second feed one revolution of the cylinder prior to starting of the heel because, in that case, it is possible to profit from the angular displacement of the control drum which is accomplished in two revolutions of the cylinder.

The control device for the members of the second feed that will be described now solves this problem and eliminates the diiiiculty mentioned above.

The control drum 33 is provided at a certain height 6 with a cam ring 43 (FIG. 5) with raised portions 34 and low recesses 35 for the actuation of the control device for the second feed.

A cam follower lever 44 has a tip 45 in contact with the ring 43. The cam follower lever 44 is fixed to the lower end of a vertical shaft 46 that, at its upper end, carries a control lever 47 and that is supported to rotate in the framing of the machine.

A spring 43 (FIG. 6) acts upon the lever 47 in such a way as to keep the tip 45 of the lever 44 against the drum 33. To the lever 47, an angle member 50 is pivoted by means of a screw 49. The angle member 50 is prevented from rotating in one direction by a stop 5l rigid with the lever 47, while it can perform small rotations in the other direction in opposition to a leaf spring 52. At the free end of the angle member 50 there is pivoted at 53 a small lever S4 which is urged towards the angle member S0 by the spring 55. The angle member 5t) carries a small endof-stroke stop dowel 56 for engagement by the lever 54. The angle member 5@ and lever 54 constitute a latch assembly.

A bell-crank lever S7 rotatable about the pin 58 carries at one end a small dowel or abutment member S9 adapted to co-operate with the angle member 5t) and the small lever 54. The lever 57 is subjected to the action of a return spring 66. At the end opposite the dowel 59, the lever 57 is connected to the link 61 which in turn is connected to the lever 62 fixed to the shaft 63. To the same shaft 63 that is rotatably supported in the framing of the machine there is xed the lever 64 that carries at its free end a small roll 65 adapted to co-operate with a cam 66 fitted to the main shaft 26 of the machine. To the bellcrank lever 57 in the proximity of the dowel 59 there is connected a bar 67 terminating in a pawl 63 (see FIG, 5a) adapted to engage in teeth of a ratchet wheel 69 forming part of a pack of discs 7) which serve to control the individual members of the second feed. The bellcrank lever 5'7, link 6l, levers 62 and 64 and roll 65 constitute a mechanical system for reciprocating the bar 67 in response to actuation by cam 66. The pack of discs 76 and the wheel 69 are mounted rotatably on the shaft 7l carried by the framing of the macmne. Said discs 7 i are provided with peripheral notches wherein small levers can engage for control of the members of the second feed. A set of discs 7@ actuate, by way of the small levers 72,` the links 73 and the levers 74, the thread-guides 42 of the second feed (see FIGURES 5, 9 and l0). A disc 7) controls, by way of the lever 75, the link '76 and the levers 77, 78, the cam or bolt di for effecting the clearing of the needles (see FIGURES 5 and 6). Finally, a disc 79 (FIGURES 6, 9 and 10) which is rotatable with the discs 7tl and is in the shape of a relief cam controls, by way of the lever Sti, the cam 4t) for the loop formation in the second feed. For constructive reasons the disc 79 is provided outside the pack 7i). Operation of the control device described above is as follows.

The lever t4 with the top 45 is normally lifted by a raised portion 34 of the ring 43 on the control drum 33 (as indicated in FIG. 6). The lever 47 is rotated about the axis 46 in clockwise direction and the angle member Si) and th small lever 54 are angularly shifted therewith. The small dowel 59 of the bell-crank lever 57 engages between the angle member Sti and the lever 54 and bears against the former. By overcoming the action of the return spring 66 the lever 57 is displaced angularly in clockwise sense and through the link 61 and the levers 62, 64, the roll 65 is disposed outside the radius of action of the cam 66. The whole control device is thus locked and the members of the second feed are kept in the position, which may be operative or inoperative, to which they had been moved by the last control effected. If the drum 33 starts a displacement of its own through an angle bringing before the tip 45 of the lever i4 a low recess of the ring 43, the levers 44 and 47 perform-under the action of 7 the spring i3-a rotation in counterclockwise direction, making the angle member and lever 57 move out of contact with the dowel 59 of the lever 57 in such a way as to disengage the dowel 59. At the same time, the lever 5d is returned towards the member 5t) by the spring 55. The bell-crank lever 57 in turn is returned by the spring 6i) and the roll 65 is brought into contact with the cam 66 that turns continually with the main shaft 26. Hence the cam 66 actuates-through the system of levers 64-,

62, 6l and 57 (see FIGURES 6 and 8)-the bar 67 and the pawl 63. In order that the pawl 68 on the bar 67 may be able to turn the pack of discs 7@ through a predetermined angle, it is necessary that the bar 67 should effect a reciprocating to and fro movement having an amplitude equal to the pitch of the teeth of the wheel 69. This reciprocating movement is caused by the shape of the profile of the cam 66 and in order that the complete movement may take place it is necessary that the roll 65 of the lever 64 should descend from the radially highest point of the profile of the cam 66 to lthe radially lowest point (to effect forward movement of the bar 67 until a new tooth of the wheel 69 is engaged by the pawl 68) and rise subsequently again to said highest point (to effect an angular shift of the ratchet wheel 69 equal to the pitch of its teeth). It is obvious that if the roll 65 does not move from the highest point to the lowest point of the profile of the cam 66, the bar 67 does not perform the forward movement and the pawl 63 cannot engage any new tooth of the wheel 69.

Consequently the return movement of the bar 67 can cause a rotation of the wheel 69 only if said bar has previously performed the entire forward movement necessary for the pawl 63 to engage a new tooth of the wheel 69.

If the drum 33 were to remain in its position as indicated in FIG. 8 with a low recess 35 of the ring 43 in front of the tip 45 of the lever 44 the cam 66 would-for every subsequent revolution make the bar 67 perform a complete to and fro movement and, therefore, at every revolution of the main shaft 26 there would take place an angular displacement by one pitch of the disc pack 7i).

However the drum 33 never stops in the position as indicated in FIG. 8 but during its angular displacement it again disposes a high portion 34 of the ring 43 under the tip d5 of the lever 44 (see FIG. 7).

When the drum 33 has reached and has stopped in the position indicated in FIG. 7, the lever i4 is lifted again at the high portion of the ring i3 and turned together with the lever 47 in clockwise direction about the axis 56. The dowel 59 however cannot enter between the member 5t) and the lever 54 because the latter is returned by the spring 55 towards the member 56. The member 50 and the lever 54 are instead made to rotate slightly about the pin 49 in opposition to the action of the leaf spring 52 (see FIG. 7). In that way it will be seen that, although a high portion 3d of the ring 43 on the drum 33 has arrived under the tip 45 of the lever 44, the control device for the members of the second feed is not yet locked but keeps being actuated by the cam 66. However, when the highest point of the profile of the cam 66 arrives again under the roll 65 and the lever 57 is consequently controlled to rotate in clockwise direction about its pin 53, the dowel 59 strikes against the lever 54, displaces it and can enter between it and the member 5i) which being no longer pushed by said dowel 59 (as in FlG. 7), is triggered by the under leaf spring 52 to its normal position (FIG. 6) and, therefore, locks the control device keeping the roll 65 out of the radius of action of the cam 66.

From the above it appears that every time the drum 33 effects a displacement destined to actuate the control de vice of the second feed, the magnitude of said displacement is such as to bring under the tip 45 of the lever A firstly a low recess 3S and subsequently a raised portion 34 of the ring 43. The unlocking of the control device takes place at the time at which the tip 45 of the lever 44 falls'into a low recess 35 of the ring, but the locking of the same control device takes place only after about one revolution of the cylinder again brings a raised portion 34 of ring 43 under said tip 45 of lever 44, thanks to the retarding system described hereinbefore. The low recesses 35 of the ring 43 serve, therefore, exclusively to unlock the control device for the second feed and those recesses 35 have a somewhat limited length so that said device effects only a single control (one complete movement of the bar 67).

Now it will be understood how it is possible to effect the control of the mechanism of the second feed one revolution of the needle cylinder before, or one revolution of the needle cylinder after, or contemporaneously with respect to the time at which the control drum 33 stops in a control position of its own.

In the first case, when it is necessary that the mechanism of the second feed should be controlled one revolution of the needle cylinder in advance of the time of stopping of the drum 33 in an angular position of its own, the recess 35 and the point of return to the raised portion 34 of the ring 43, are arranged immediately at the beginning of the displacement through which the drum 33 is shifted. Since the time required for the drum 33 to effect its entire angular displacement is, as mentioned above, about equal to the duration of two revolutions of the cylinder and since the retardation caused by the retarding system in effecting the control is about equal to the duration of one revolution of the cylinder, the control of the second feed is actually carried out one revolution of the cylinder in advance of the stopping of the drinn 33. This arrangement should be selected at the beginning of the formation of the heel of the stocking where only the second feed should be rendered inoperative one revolution of the cylinder before the machine is controlled by the drum 33 to start the formation of the heel.

When instead it is necessary to control the mechanism of the second feed one revolution of the cylinder after the time when the drum 33 is stopped in an angular position of its own, the recess 35 and the point of return to the raised portion 34 of the ring 43 should be arranged at the nal end of the displacement through which the drum 33 shifts. The retarding system provides in that case operation of the control of the second feed one revolution after the stopping of the drum 33. This arrangement is selected, therefore, at the end of the formation of the heel of the stocking where the second feed should be again rendered operative one revolution of the needle cylinder after the machine has nished the heel.

With the intermediate position of the recess 35 and of the point of return to the raised portion 3ft of the ring 43,- it is possible to obtain the operation of the control of the second feed contemporaneously with the stopping of the control drum 33.

Thus, where it is desired to have three successive courses produced by the first feed, that is a course D immediately following the production of the heel and two courses C and E respectively preceding and succeeding the course D, as in FIGS. l, 2 and 3, the control drum 33 is angularly displaced to the control position thereof corresponding to the formation of the heel during the knitting of courses B and C, then remains in that position during course D, which immediately follows production of the heel, and is further angularly displaced from that control position during the courses E and F. In order to ensure that course C preceding course D is produced by the first feed, cam ring 43 of drum 33 has a recess 35 located to receive the nose 45 of cam follower lever A at the beginning of the needle cylinder revolution corresponding to course B so that the abutment 59 of lever 57 is then released by angle member Si) and lever 54 constituting the latch assembly and cam 66 can cause u reciprocation of bar 67, by way of the mechanical system 57, 61, 62, 64 and 65, for disposing discs 70 in the position for rendering inoperative the second feed mechanism at the conclusion of the needle cylinder revolution corresponding to course B. Another recess 35 is provided in cam ring i3 of drum 33 and is located to receive nose 45 of cam follower lever 44 at the commencement of the needle cylinder revolution corresponding to the course E so that the mechanical system 57, 6l, 62, 64 and 65 is again unlocked to permit reciprocation of bar 67 by cam 66 for turning discs 7) to the position for returning the second feed mechanism to its operative condition at the completion of course E.

The profile of the cam 66 possesses, as previously mentioned, a radial highest point and a radial lowest point (see FIG. 6). The contour from the lowest point to the highest point of the profile in the direction contrary to the rotation of the cam is conveniently stepped. With this stepped contour, the turning of the pack of discs '7d through the angular extent of the pitch of a single tooth on ratchet wheel 69 also takes place in a step-by-step manner during each full revolution of cam 66. Thus, each step of cam 66 imparts a portion of a rack movement to discs 7f3, and the several steps of cam 66 acting successively on follower 65 result in a single full tooth rack of discs 70. As a consequence thereof, it is possible at times to control the individual members of the mechanism of the second feed (cam 46, bolt 4l, thread-guide 42) out of phase by pre-arranging the notches in the discs 70 in a convenient way. It is clear that the above described embodiment of the present invention is, in practice, susceptible of various modifications without departing from the scope of the present invention.

I claim:

l. In a two-feed circular knitting machine for producing patterned hosiery wherein tuck loops in alternate courses define the pattern and having a rotary needle cylinder, first and second feed mechanisms, and at least one intermittently rotated control drum; the combination of a single design device associated with the first feed of the knitting machine, and a control device actuated by said control drum and engageable with said second feed mechanism to render the latter inoperative one revolution of said needle cylinder before the commencement of the knitting of the heel of hoisery being produced so that the last course effected during continuous rotary movement of the needle cylinder is made by the first feed with pattern defining tuck loops being formed therein by the operation of said design device, said control device comprising a retarding system effective to cause said control device to perform a control movement of said second feed mechanism one revolution of said needle cylinder after said intermittently rotated control drum has stopped in a control position thereof in order to again render operative said second feed mechanism one revolution of said needle cylinder after completion of the heel so that three successive courses are then produced only by said first feed.

2. In a two-feed circular knitting machine, the combination as in claim l; wherein said control device includes an axially arranged pack of discs rotatable about the axis thereof, means engaging said discs and actuated by the latter in response to rotation of said pack to directly control said second feed mechanism, a ratchet wheel connected to said pack for turning the latter, a reciprocable bar having a pawl thereon engaging said ratchet wheel to effect step-by-step turning of the latter in response to reciprocation of said bar through a stroke of predetermined length, a rotataed main shaft of the knitting machine having a cam thereon, a mechanical system engageable, at one end, by said cam and connected to said bar for reciprocating the latter in response to turning of said cam with said main shaft, and means actuated by said control drum and effective to move said one end of the mechanical system into and out of the range of said cam during an angular displacement of said control drum.

3. In a two-feed circular knitting machine, the combination as in claim 2; wherein said control drum has a cam ring thereon provided with spaced apart recesses and raised portions between the latter, and said control drum is intermittently rotated through angular displacements enclosing the distances between the successive recesses of said cam ring; and wherein said means actuated by said control drum includes a pivoted cam follower lever urged into engagement with said cam ring to contact the latter at a raised portion of the latter whenever said control drum halts during the intermittent rotation thereof, a control lever movable angularly with said cam follower lever, and a latch assembly engageable by said mechanical system and operative, prior to an angular displacement of said control drum, to hold said one end of the mechanical system out of the range of said cam for preventing reciprocation of said bar, said latch assembly further permitting movement of said one end of the mechanical assembly into the range of said cam for actuation by the latter to reciprocate said bar upon contact of said follower lever with a recess of said cam ring and until said cam has undergone a complete revolution following the return of said follower lever to contact with a raised portion of said cam ring.

4. In a two-feed circular knitting machine, the combination as in claim 3; wherein said mechanical system includes a rockable bell-crank at the other end thereof yieldably urged in the direction for moving said one end into the range of said cam and carrying an abutment member; and said latch assembly includes a first member pivoted on said follower lever, a second member pivoted on said first member and yieldably urged toward the latter to close an angle enclosed by said first and second members, and spring means urging said first member to an operative position relative to said follower lever where, with the latter contacting a raised portion of said cam ring and said first and second members spread apart, said abutment member engages between said second member and said first member and the latter blocks rocking of said bell-crank in said direction for moving said one end of the mechanical system into the range of said cam, said first and second members being relatively arranged so that, when said follower lever contacts a recess of said cam ring, said rst and second members are withdrawn from engagement with said abutment member and said angle between the first and second members is closed to prevent the reentry of said abutment member therebetween until rocking of said bellcrank by engagement of said one end of the mechanical system with said cam causes said abutment member to angularly displace said second member away from said first member while said follower lever contacts a raised portion of said cam ring.

5. In a two-feed circular knitting machine, the combination as in claim 4; wherein said cam has a radial high point and a radial low point, and the contour beween said radial high and low points, in the direction opposed to the direction of rotation of said cam, has a stepped configuratiaon so that the reciprocating stroke of said bar, in one direction, includes successive, stepby-step advances, and similar step-by-step advances are imparted to said pack during turning of the latter.

6. A method of knitting seamless stockings with a main yarn and an auxiliary yarn in a circular knitting machine having a rotary cylinder and needles, a main feeding and knitting station, and an auxiliary feeding and knitting station, comprising the steps of knitting the leg of said stocking with both yarns simultaneously, a main yarn being knit at the main station with tuck stitches at intervals and an auxiliary yarn being knit at the auxiliary station with plain stitches, whereby the leg fabric has alternate tuck and plain courses, withdrawing the auxiliary yarn from the fabric one course before goil ing into the heel, whereby the last leg course before the heel is a tuck course knitted at the main station, knitting the heel by reciprocatory knitting at the main station, and knitting the fGot of'said stocking with both yarns simultaneously, a main yarn being knit at the main station with tuck stitches at intervals and an auxiliary yarn being knit at the aum'liary station with plain stitches, wherein the foot knitting of the auxiliary yarn at the auxiliary station is initiated one course after the heel.

References Cited in the file of this patent UNITED STATES PATENTS West Nov. 26, Bcsworth May 10, Dickens Oct. 25,V Manger et al. July 15, Lawson Feb. l0, Hill Aug. 9,

Claims (1)

1. 6. A METHOD OF KNITTING SEAMLESS STOCKINGS WITH A MAIN YARN AND AN AUXILIARY YARN IN A CIRCULAR KNITTING MACHINE HAVING A ROTARY CYLINDER AND NEEDLES, A MAIN FEEDING AND KNITTING STATION, AND AN AUXILIARY FEEDING AND KNITTING STATION, COMPRISING THE STEPS OF KNITTING THE LEG OF SAID STOCKING WITH BOTH YARNS SIMULTANEOUSLY, A MAIN YARN BEING KNIT AT THE MAIN STATION WITH TUCK STITCHES AT INTERVALS AND AN AUXILIARY YARN BEING KNIT AT THE AUXILIARY STATION WITH PLAIN STITCHES, WHEREBY THE LEG FABRIC HAS ALTERNATE TUCK AND PLAIN COURSES, WITHDRAWING THE AUXILIARY YARN FROM THE FABRIC ONE COURSE BEFORE GO-

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