GB2203172A - Device for yarn change selection on knitting machines - Google Patents

Description

"DEVICE FOR YARN CHANGE SELECTION AND DRIVE ON Kill T! IN G MACHINES" T h

e s e 1 e c t i n 9 mac h i nes, & single machines The double-cylinder apparatus c f yarn c o 1 o u r, r e t a i n i n 9 are not fed..

It is clear that in order to enable and disable the yarn guides of each yarn selector apparatus, it is necessary to prearrange a yarn change selection and drive device which, according to a pre-established program, is capable of turning a determined yarn guide to operating and of turning to not-operating, or keeoing operating, the other yarn guides, with the simultaneous cutting and retention of the end of th e yarn which is turned to not-operating status.

Yarn selector apparatuses are 22L_se perfectly known present and f o r such a double-cyl cylinder machines, with either single or knitting machines..

invention relates to a device for driving the yarn change on ktiittin,.. knitting machines, p 1 1.

1. a e 011 inder single-cylinder machines, double flat needle-beds., and, in partizular, known circular machines provided with a large number formation points (denominated order to make it possible manufactured, which have areas different yarn types, in corr a suitable apparatus - is prearranged, which comprises guides for feeding yarns different as well as with the elements for the ends of, the yarns which from L 11 e a r e t o be of yarn feed and stitch It y a rn f e ed s, 6 rid i ri knitted fabrics to be with different colcurs or.

eed espondence of each yarn - denominated "yarn selector a p 1 U r a 1 i t y i n type 0 _ cutting, and time to time, - 1 not- 2.

in the art. They comprise type or colour. to be fed, a movable yarn guide (also clamp, a movable knife, selection device.

The yarn change, and disabling the movab in the same region denominated "selvedge" exchanged with The guide of command d e v i c e, y a r n g in t h e e 1 e m e n t e 1 a s t i c two cams the yarn selection an operating, or, According to a for each yarn of different and namely set of elements, denominated a stationary "jetc-ur"), k n i f e and 1 a.a obtained by respectively enabling le yarn guides, takes place always which on the knitted fabric is wherein the two yarns which are each other, are overLapped. element associated with s e 1 e c t i o n the yarn selector apparatus, of the yarn selection and leads one of the 4- wo heels uide on the path any are movin selector programmed prior art.

upon the yarn each yarn programmed change drive provided on the same of a relevant thrust cam, whilst absence of actions by the said selection the other heel from said two heels is means, on the path on a return cam, led, by s a i d r r e d to S, so that, according to the the concerned yarn guide is led to respectively, not-operating position.

the heretofore technique known from the each yarn selector apparatus is provided with its own associated device for yarn change selection and drive.

w h e r e i n 9 by a relative motion as refe apparatu This yarn change selection and drive device may be of drum type, revolving step-by-step, and peripherally bearing, along circular tracks, pins suitable for acting on the selection element of each yarn guide of the yarn selector apparatus, but solutions are also known, which 3.

use e 1 t control associ selector selector art, w i t h d e v i c e ( s) accordina ctromagnetic actuators which can be ed by an electronic central unit, and ated with a relevant yarn guide of apparatus. Therefore, in any case, apparatus is provided, according.to own yarn change selection order to lead the relevant yarn pre-established program, to a by said guides to come yarn guides i t S n t o a position wherein they thrust cam, or non-selected position, disabled by said return It is evident that large number of correspondingly to enable the can be enabled yarn wherein the c a r11. in a knitting machine feeds, and, therefore, yarn yarn large number of apparatuses, the fact that each of apparatuses must be equipped with its selection and drive, which, i 1 e c t r change version, requires the movable yarn are, constitutes a immaterial Now, economic i t i S machines should be needle selection, production of the of the needles must each yarn feed in should be should program are each t h e y a rn each yarn t h e p r i o r and d r i v e g u i d e s, se l e c tled movable t o a a r e h a v i n 9 a W i t h a selector such yarn selector own device for yarn n t h e electronic as many e omechanical actuators as guides of the yarn selector apparatus considerable complication, and a non burden.

also well known that the knitting furthermore equipped with a system for the operator to program the t patterns. This seleciion out in correspondence to enable most differen be carried of such a way that for each needle it r the same needle remain not-operating, whether is should be operating, or whether it should retain the stitch. In possible to decide whethe 4.

case of double-cyLinder machines, or pLa cylinder machines or doubleneedle-bed flat these possible selections, also that of deci t h e or of the other needle These yarn selection systems may of mechanicallydriven type, or, in the most up-to-date machines, of electromechanically driven, or electronically controlled type. In particular, the prior art has already proposed to use electromechanical actuators controlled by signals suppLied by an electronic central unit, and suitable for acting on pattern heeLs of purposely provided selectors housed inside the slots provided on the cyLinder(s), which contain the needles, under the same needles, with the interposition of needle pushers. The electronic central unit generates the control signals, which command the actuation of the electromechanical actuators according to the pattern to be produced in the knitted fabric, as detected by a pattern analyser, and processed by a t e & sil ng I e machines, to ding whether stitch should be achi.eved on the needles of the one, bed, adds up.

computer.

In a double-cylinder, multifeed machine, in order to be able to carry out, in correspondence of each yarn feed, on a single station, the three basic selections (needle not operating, needle operating in plain mode or n purl mode, needle retaining the stitch), such an ion system may comprise, successive sets of case also the number w i t h respective associated electromechanically-driven for each yarn feed, electromechanical actuators, of movable cams is reduced to the upper cylinder, they electromechanical actuators.

s e 1 e c t two in that two cams too driven by whilst the cams associated 5.

with the lower cylinder are all stationary.

Normally, the selection of the needles is riot carried out in the selvedge region cf the knitted f abri c. in which region a fabric in the true sense is not formed. This region has a width corresponding to a certain number of needles (for example, approximately 20 needles), and therefore a. span of a certain width is available, wherein the needle selection system remains generally inactive.

The purpose of the present invention is of simplifying the selection and the drive of the yarn change in knitting machines, in the sense that it pursues the end of preventing that with each yarn guide of the yarn selector the drive of associated.

In order invention selection and th s e 1 e c t i o n t o s o 1 v e moves from the a device for the selection and change of its own has to be present f o r t h e e drive of the yarn change, the needle system and means, which exist in the knitting machines, in the region thereof which is concerned by the formation of the selvedge of the knitted fabric, i.e., the region wherein no true fabric is formed, and wherein the selection of the needles is not carried out.

According to the present invention, a device is therefore provided for the selection and the drive of the change of the yarn for the yarn guides of yarn selector apparatuses, each comprising a plurality of groups of elements, each constituted by a movable yarn guide provided with two drive heets and subject to-the action of elastic means, by a clamp and by a movable knife and a stationary knife, in a knitting machine having a first this problem, the idea of exploiting, 6.

portion provided with a pluraLity of slots parallel to one another, inside which needles with relevant with pattern heels, neeldle pushers and needle are inserted, and a second portion bearing, for feed, besides selection means acting on the pat of the selectors, as well as drive cams acting needle pushers and needle actuators, one from s se l ector k n i t t i n 9 machine cause selectors actuators each yarn tern heels on s a i d aid yarn apparatuses, with said first portion of the machine or said second portion of the knittin,g being connected with drive means in order to a relative motion between said two portions, ano with said first portion bearing thrust and return cam means suitable for acting on the drive heels of the yarn guides of the yarn selector apparatuses in order to push the yarn guides to their active position, and return them to their inactive position, the device being characterized in that inside determined slots of said first portion of the machine, concerning the region of formation of the selvedge of the knitted fabric, there are inserted, besides the selectors and the needle pushers, also pu.shing rods, instead of relevant needles, which are equipped with heels located at different heights, the number of the slots inside which said pushing rods are inserted being equal to the number of the- movable yarn guides provided in ea.ch yarn selector apparatus and each slot being associated with one of said yarn guides, that on said second portion of the machine there are installed, each associated with a yarn selector apparatus, sets of intermediate movable elements, wherein each set from said sets comprises as many movable elements as the movable yarns guides are, which are 7.

provided in each yarn selector apparatus, each of said intermediate movable elements being associated with a determined movable yarn guide of all of the yarn selector apparatuses, and being provided with a selection tooth which is suitable for acting on said associated yarn guide, said pushing rods, during the relative movement between said two portions of the machine, and as a function of the position of said selection means, being suitable for acting, through their heels located at different heights, each on a related intermediate movable element of said sets, intermediate element, associated yarn quid against the action of with the thrust cam me in order to lead, by means of the one of the drive heels of the of the yarn selector apparatuses, said elastic means, to cooperate ans borne the said first portion of the machine, or to enable said elastic means to lead the other drive heel to cooperate with the return cam means.

It clearly appears how the device for the selection and the drive of the yarn change according to the present invention is not provided with distinct selection means associated w$th each yarn guide of the yarn selector apparatuses, but uses the needle selection means in order to select, in correspondence of each yarn feed point, through the selectors, needles pushers and pus.her rods running inside the relevant slots of the first portion of the machine, as well as by means of said intermedia-te movable elements provided on the second portion of the machine, the yarn guide(s) of the yarn selector apparatus associated with said yarn feed point which, in this yarn feed point, must operate, and turn to notoperating the other yarn guides of the same yarn selector apparatus.

8.

in particular, said selection means used order to perform the selection of the needles, performing the selection of the yarn guides of selector apparatuses, can be constit electromechanical actuators of a type known prior are, suitable for acting on the pattern the selectors running inside the slots of portion can b e of the machine, and provided, which sends electromechanical actuators, the pattern of the knitted fabr detected by a computer.

In a specific case, the first portion of the machine, wherein the parallel slots are provided, is the movable portion, and the portion bearing the selection means (the actuators), the drive cams and the yarn selector apparatuses, is the stationary port machine i of When the said first portion the cylinder(s) stationary or constituted cylinders and bearing the devices, the yarn selector which correspondingly In multifeed are the particular ( i. e., knitting machine, with needle selection and apparatuses at each b o t h i n and f o r t h e ya rn uted by f rom the h e e 1 s of the f i r s t an electronic central unit actuation signals to said according to the colour and ic to be manufactured, as processed by a pattern analyser, and o n s a circular knitting machine, tChe the machine can be constituted by of the needles, which can be ei p o r t i o n surrounding revolving, and the second by the relevant skirts drive cams, apparatuses, either revolving case of a double-cylinder, multi-yarn-feed t he and so t h e r is the selection f o r t h, or stationary.

points) circular revolving cylinders and stationary drive devices, the yarn selector yarn feed must be mounted in a 9.

vertical position on the stationary portion surrounding the upper cylinder, i.e., with the yarn guides Lleing vertically positioned, so that each yarn fed by a yarn guide just selected to operate cannot be directly taken by the needle eye. Therefore, in this case, the machine must be provided with a further element, denominated "hook", which is installed such to be radially sliding inside a support fastened to the interior of the upper cylinder, said hook having to be controlled to protrude outwards for a short time, and return back into its seat, during the revolutions of the machine during which a yarn change is programmed, and limitedly to the yarn feed points wherein a yarn guide change takes place, in order to hook the yarn operating, bring it'under the eye of the needles, and then disengage again from this yarn. In this particular case, according to the invention, the yarn change selection and drive device carries out the drive of said hook too, still exploiting the needle selection system existing in the machine, in the region concerned by the formation of the selvedge of the knitted fabric.

In order to do so, a further slot provided in the cylinders of the machine is used, inside which above a selector, a needle pusher and a pusher rod, a particular, further drive pusher rod is provided, which, through a return bell crank, is operatively linked to the hook -in order to drive, thanks to axial movements inside its relevant slot, the hook to radially move outwards and inwards again, in correspondence of the yarn feed points wherein a yarn change is programmed, in order to bring the new yarn fed by the yarn guide just enabled by the fed by the yarn guide just turned to 10.

respective n e e d 1 e s eye of t short time position, a is mounted on the support linked to the same hook, return s a i d w i t h yarn selection dev in as much as this must be s a i d hook of i n stroke of the hook element is shifted in the yarn and disengage In the following, greater detail, by drawings, which embodiment applied to a feed, circular knitting In F i 9 u r e electronic actuators; ice, under the eye of the new yarn, once engaged by the he needles, unhooked from the hook a before returns to its inwards suitable unhooking element is provided, which the hook and is operatively such a way that, during the position, contact towards its inwards order to come into it from the hook. the invention is disclosed in referring to.the hereto attached show an exemplifying form of practical double-revolving-cylinder, multimachine.

the drawings:

1 shows a generic block diagram of the central unit and of the electromechanical Figure 2 is a diagram depicting the development the cam skirts and of the selection devices for one yarn feed point of the machine according to path II-II of Figure 3; Figures 3 and 3a are diagrams showing verti sectional views taken along path III-III of Figure 2 the point in time cylinders inside which guide of the yarn feed point are of selection and of non-se guide; c a 1 a t t-h e o f a slot o f elements of a yarn yarn selector apparatus associated with that housed respectively in the condition lection of the relevant yarn of the passage the selection 11.

Fig.ure 4 is a diagram showing a vertical sec-tional view according to path IV-IV of FigUre 2, at the point in time of the passage of the same slot of the cylinders as shown in Figure 3; Fi-gure 5 is a diagram showing a vertical sectional view taken along path III-III of Figure 2, simila that shown-in Figur passage of the slo selection and drive F i g u r e 6 is a view according to path shown in Figure 4, passage of the sam Figure 5; Figure 7 is a d view taken along pat Figure 8 is a d view taken along pat Figures from 9a housed inside slots of the cylinders; r t 0 3, but at the point in time of the of the cylinders wherein the book lements are housed; iagram showing a vertical sectional IV-1V of Figure 2, similar to that but at the point in time of the, slot of the cylinders as shown in iagram showing a horizonta h VII-VII of Figure 4; iagram showing a horizonta h VIII-VIII of Figure 6; to 9e show different drive 1 sectional 1 sectional elements Figures 10 and-11 are diagrams respectively showing a side view and a front view of a yarn selector apparatus; and Figure 12 shows a partially sectional view of the hook support.

Referring, first of all, to Figure 1 of the drawings, in it the double-cylinder, multifeed (multi yarn-feed-points), circular knitting machine is schematically represented by the block M.' With the machine, an electronic central unit is associated, which essentially comprises a pattern analyser DA, an on-board 12.

computer CAM, and an encoder CO. This latter s upplies synchronism signals "sin", needle count signals "cont M' and cylinder revolution count signals "cont C. For each yarn feed 1, 2, and so forth, of the machine, provided are two selection actuators Al and A2, as well as two actuators AC1 and AC2, to bring two movable cams Cl and C2 of the upper skirti associated with the upper cylinder of the machine, to their operating position, or to their non-operating position.

The computer CAM processes the i nformation received from the pattern analyser DA and from the encoder. CO, and sends the control signals to the various actuators, in synchronism with the revolutionary motion of the cylinders, as a function of the pattern to be reproduced.

The pattern to be reproduced D has a selvedge region C, wherein no fabric in the true sense of the word is formed, and which has a width corresponding to a certain number of needles. Furthermore, such pattern has regions X, Y, Z, and so on, to be accomplished with yarns having different colours.

In Figure 2 6 portion is shown, in development, and seen from the interior according to path II-II of Figure 3, of the stationary portion of the machine which surrounds the revoLving.cylinders, substantially relevant to one yarn feed. At the top, on same Figure 2, two cams for driving the yarn guide of the yarn selector apparatuses - integral with the upper cylinder - are furthermore shown, which movable cams are disclosed in greater detail in the following.

Said stationary portion of the machine substantially comprises a lower cam skirt 10, an upper cam skirt 11, a 13.

ring 12 of stationary extraction cams, constituted by electrorinechanical two of them, indicated by the 14 in Figure 2, and corresponding shown in Figure 1, as well as a yarn generally indicated by the reference each yarn feed. electronically- _se known, and in detail. In 11 be eno-Ligh to a plurality actuators A1 and selector numeral 1 The controlled therefore order to understand thei state that each actuator 13, 14 compri selection levers 16 hinged to a body 1 having a fork-shaped end, which is engaged anchor 18 movable between two angular posi tion of the electromagnetic field generated ectromagnet 80 against the action of a the electromagnet 80-is de-energiz lifted, and does not interfere pattern heel of a respective in A2 us, apparat 5, are provided per electromechanically-driven or selection actuators are per they are not herein disclosed it sha S e S 7, ac el magnet. When lever 16 is corresponding is discussed electromagnet i interfere with With each cam, respectively associated; also selectors.

As it can be machine comprises cylinder cylinders selection devices Y-driven levers, wherein reference numerals '13 and to the selec.tion r function, o f each of them by a driving tions under the by an permanent e d, t h e w i t h a selector which the following, whilst when the s excited, the lever 16 is sunk-, and can said heel of the selector.

actuator 13, 14, a stationary extraction 19 and 20, of the ring 12 is said -cams 19 and 20 act on said seen from Figures 3 through 6, the a lower cylinder 21 and an upper 22 axially superimposed to it, both of said being driven in a known way to revolve around 14.

their common axis, which in said Figures is on the righthand side, and is not visible. The direction of revolution of the cylinders 21 and 22 is shown by the arrow 23 in Figures 2, 7 and 8.

The cylinders 21 and 22 are provided with lined-up peripheral slots. In most of these peripheral slots of the cylinders 21 and 22 there are inserted the needles, and the respective elements for needle selection, and for driving the movements of the same needles inside their slots for the formation of the knitted fabric.This portion of the machine, i.e., the slots of the cylinders with the needles, is not depicted, and it is not herein disclosed, because it is known from the prior art, and does not relate to the present invention.

But the cylinders 21 and 22 are provided with a certain number of slots arranged side-by-side to eacin other, which correspond to the region of the selvedge C of the knitted fabric unde region a true fabric is not the needles is not carried out.

shown in Figures 7 and 8.

According to the present invention, it is proposed to use for the selection and the drive of the yarn guides of the yarn selector apparatuses, and of the hook, slots which are not used for the selection o needles. In particular, with each determined yarn way of production, in which formed, and a selection of Some of these slots are these f the guide of the yarn selector apparatus, one of said slots is associated, and a further slot is associated with the hook. In as much as, as it is shown in detail in the following, each yarn selector apparatus is equipped, in the instant case, with four yarn guides, fou lined-up 15.

slots of the lower cylinder and of the upper cylinder are associated with said yarn guides.

21, t h e In Figure 8, the four slots of the lower c,,liride.,, each associated with one of the four yarn guides of yarn selector apparatuses, are indicated by the reference numerals 24, 25, 26, 27, and the slot associated with the hook is indicated by the reference numeral 28; whilst in Figure 7, the corresponding four slot yarn guides of the yarn selector with the slots from 24 to 27, 30, and S of the upper cylinder 22 associated with the four apparatuses and Lined up are indicated by the 31, 32, and the slot lined up with the slot 28 numeral 33.

is partially passing numerals 29, with the hook, ted by the reference reference associate i s i n d i c observed that the slot outside to inside the upp reasons which are detailed The elements provided inside said slots from 24 to 28 of the lower cylinder 21 are identical to one another and are, from the bottom to the top: a selector 34, a needle pusher 35, and a needle actuator, or dummy slider 36. The only difference consists in that the selectors 34 are each provided with a pattern heel 37 which is-located at a different height, in order to be capable of being actuated by a lever 16 of the actuators 13 and 14, positioned at a corresponding different height. -The selectors 34 are hinged at the bottom, by means a rounded end of their own 38, and at the top have a fork-shaped end 39 with a tooth 40, with which the extraction cams 19, 20 cooperate. The needle pushers 35 are always engaged, at their lower end, inside the fork 39 of the 1+. should be f r o w. r cylinder 22, because of the in the following.

16.

relevant selectors 34, and are each equipped with a heel 41, whilst the dummy sliders 36 are each provided with a heel 42.

Inside the slots pushing rods 42a-42d inserted, each 44d, wherein the 42d are all at the same are at different heights Finally, inside a drive pushing rod 29-32 of the upper cylinder 22, (see Figures from 9b-9e) are of them having a heel 43 and a heel 44a heels 43 of all on the pushing rods 42a- height, whilst the heels 44a-44d the 45 is same slot 33 of the upper provided, which has which is at the height of the heels pushing rods 42a-42d (see Figure 9a), but is 1 the heels 43, as well as an intermediatE protrusion 47.

cylinder 22 a heel 46 43 of t h e onger than circular On the stationary portion of the machine a set of intermediate movable elements, generally indicated by the reference numeral 48, are mounted at the top, in and associated with the correspondence of each yarn feed, of the relevant yarn feed. The each set 48 are constituted by levers which and are levers, through a relevant selection of its own, being capable of acting selector can be actuated i.

51 and 52 pivot 53 57 guides of the yarn levers 49-52 the pivot 53 yarn selector apparatus movable elements of 49, 50, v e r t i c a 1 each of these 54, 55, 56, of the yarn their turn, said e., made revolve around by the heel 44a-44d of a relevant pusher rod 42a-42d, with said heels 44a-44d of the pusher rods 42a-42d being at different heights, as previously said.

are rotatably mounted around a superimposed to one another, tooth on one apparatus. -In lifted. on the in their lower To this regard, it should be stressed that, when the pusher rods 42a-42d are in their lower position inside their respective slots 29-^,2 the heel 44a of. the puitlcrod 42a is at a height lower than the levers 401-52 that, in order to act, on the lever 49, said pusher 42a must be contrary, the pusher rods -42d show, position, their heels e x a c t 1 y 50-52, levers, r o d 42b 44b-44d levers they act 011 said their action, they their. heels 44b-44c] tr, 49-52.

so at the same height as of the so if they are not lifted, whi lst, in order to exclude must be lifted in order to lift higher heights than of the levers Thus, a precise coordination exists betweer slots 24-27 of the lower cylinder 21 with the 34 which are provided inside and which are provided pattertn heels 37 located..t difirerent hights, and tne. sloILS Of Lne'upper cylinder 22 with the pusher rods 42a-42d whi.ch are provid ed inside. 11-hem, thlroun't the intermediate levers 49-52, and the;"ci,r J.1 L1 L yarn guides of each yarn selector apparatus 15.

r, varn select^r mnnnrm+"c respective t h e selectors greater In the depicted case, 't h e comprises four sets of choice, four different yarn types, or four yarns having different colours. Each of these four sets is composed by a yarn guide 58a or 58b or 58c or 58d, by a clamp 59a or 59b or 59c or 59d, by a movable knife 60a or 60b or 60c or 60d with a recess 61, and by a stati ona ry kn i f e 62a or 062b or 062c or 62d. The yarn guide and the movable knife of each apparatus are shiftable inside the support frame 63 of the yarn selector apparatus, wherein the movable knife is dragged is shown in detail in Figures 1.0 and 11.

yarn selector apparatus 15 elements for feeding, upon 18.

by t h e thereof, integral 1 t 58b or acting on opposition 54-57 yarn guide during the end steps of the and the clamp and the stationary with said support frame.

should be observed that each yarn guide 508a or 58c or 58d is subject to the action of a spring 64 the rear side of the same yarn guide, in to the possible action by a selection tooth of an associated intermediate lever 49-52. Each yarn guide 58a or 58b or 58c or 58d has then, on its tang, twoopposite heels, respectively indicated by the reference numerals 65 and 66, and when not subject to the action of the selection the associated intermediate lever 49-52, causes its heel 66 to be pushed towards the the cylinder, whilst, under the action of tooth of the associated intermediate lever, 1, n i f e a r e lie yarn guide is ooth 54-57 of he spring 64 interior of he selection it is t h e heel 65 to be pushed towards the outside of the cylinder.

From the above, it clearly appears that the selector 34, with the relevant pattern heel 37 at a determined height, inside the slot 24 of the lower cylinder 21, through the pushing rod 42a with heel 44-a inside the slot 29 of the upper cylinder 22, and through the intermediate lever 49 with selection tooth 54 is destined to select the yarn guide 58a of the yarn selector apparatuses 15; and the selector inside the slot 25, through the pusher rod 42b with heel 44b; and the lever 50 with tooth 55 is destined to select the yarn guide, and so forth.

Then the upper cylinder 22 bears at its top, integral with it, a support 67 (see, in particular, Figures 2 and 10) for two cams 68 and 69, which, therefore, revolve together with the same upper cylinder.

19.

The cam 68 is a thrust cam, and the cam 69 is a return cam, and these two cams are destined to act on the heels and respectively 66 of the yarn guides 58a-58d, according to the position which these heels take. If, owing to an occurred enabling selection, the heel 65 of a determined yarn guide protrudes from the support frame 63 of the relevant yarn selector apparatus 15, at the passage of the thrust cam 68 this yarn guide is pushed to take its active position (lowered position). If, vice versa, owing to a disabling selection, the heel 66 of the yarn guide protrudes towards the interior of the cylinder under the action of the relevant spring 64, the yarn guide is pushed by the cam 69 in order to take its inactive (Lifted) position.

The same cams 68 and 69, as they - during their integral revolution with the cylinders of the machine - reach the various yarn feed points, drive the yarn guides of all of the yarn selector apparatuses located in correspondence of said yarn feed points.

The thrust cam 68 has an inclined plane 68a suitable for pushing. downwards the yarn guide of each yarn selector apparatus to be turned to operating, up to the point wherein the new yarn can be enganged by the hook, as it is better explained in the following, whilst the relevant mobile knife is not yet dragged downwards by the yarn guide, and therefore keeps still clamped the end of the new yarn. The horizontal plane 68b of the cam 68 keeps the yarn guide to be turned to operating in a position of yarn engagement by the hook, and a further short inclined plane 68c of the cam 68 furthermore pushes downwards the yarn guide to be turned to operating, so 20.

that it drags with itself the relevant mobile knife, up to release the end of the yarn which was retained by thle relevant clamp, after that the new yarn has formed the stitch. At the end of the downwards stroke of the ya..,.ri guide, the relevant mobile knife presents its recess 61 completely open and ready to receive the yarn in case the same yarn guide is removed from its operating position, and made lift again.

Also the return cam 69 has a first inclined plane 69a, which returns the yarn guide to be turned to not operating, up to make it place the yarn inside the hollow 61 of the relevant movable knife. The horizonta 69b of the cam 69 keeps the yarn guide partially inwards, until the hook, by moving outwards and again, may engage the yarn of the is being turned to operating.

p 1 a n e p us tied inwards only yarn guide which Finally, the further inclined plane 69e of the return carn returns furthermore upwards the yarn guide turned to not-operating, which drags upwards the relevant mobile knife: this latter firstly clamps the yarn against the relevant stationary clamp, and then cuts its against the relevant stationary k n i f e The hook, its selection and its drive, and finally its function, is now disclosed.

In a determined position inside the upper cylinder 22, a support 70 is fastened (see Figures 5 through 8 and 12). Inside a vertical slot of said support 70, sLidingly housed is the hook 71, which is provided with a hook shaped end 72. The book 71, in correspondence of a protruding portion.71a, is provided with a small side pivot 73, against which a fork-shaped end is engaged of a 21.

bell crank 74, which is rotatably mounted around a horizontal pivot 75 inside the support 70. The, fork-shaped end of the bell crank 74 is, on the contrar%,'.,, in engagement with the circular protrusion 47 of the drive pushing rod 45 provided inside the slot. 33 of thel upper cylinder 22. It should be observed that the bell crank 74 for actuating the moving outwards and the return moving inwards of the hook 71 is perfectly radially lined up with the through-slot 33 passing through the wall of t h e u p per cylinder 22, so as to allow the drive to be transmitted from the pushing rod 45 to the bell crank 7A, and consequently to the hook 71.

Inside a horizontal slot 70a of the support 70, 2 yarn unhooking lever 77 is furthermore rotatably mounted around a vertical pin 76 (see, in particular, Figures 7 and 8). This lever 77 has a side hollow 77b formed by a rear tooth 77a opposite to an end portion 78, and the protruding portion 71a of the hook 71 is suitable for entering such hollow 77b during its movement. In this way, the lever 77 is automatically made revolve around the vertical pin 76 during the outwards and inwards movements of the hook 71. When the hook 71 is in its - inwards position inside the support 70 (see Figures 5 and 7), the end portion 78 of the lever 77 is to the left of the hook-shaped end 72 of the hook 71 (viewing at the machine from outside the cylindeYs - see Figure _7), whilst, during the outwards stroke of the hook 71 (see Figure 8), the end portion 78 of the unhooking lever 77 is moved far away, to the right of the hook-shaped end 72 of the hook 71. Approximately at the middle of the inwards return stroke of the hook, when this latter has 22.

78 gets hook 71, from the stroke.

taken the new yarn fed by the operating, bringing it under the unhooking lever 77 is made rotate and its end portion shaped end 72 of the disengages the yarn its inwards return The trajectory of outwards and inwards movements of te hookshaped end 72 of the hook 71 is shown in Figure 8 by the chain line 79.

To the skirt 11 which surrounds the latcl-i-or)eriina cam yarn guide turned to eye of the needles, thle Leftwards by the hook, approached again to the hookcontinues its stroke and hook before this latter ends 22 a yarn guide, 81 (see 5-6) is fastened, w herein a horizontal provided, which enables the hook-shaped end 72 hook 71 to reach its end position, in which it the new yarn.

The lower set of cams selectors sliders 36 a r e the elements movements cylinders they are not f o r t h e skirt 10 provided 35, w h i c h t r a c k X1 extracted skirt 10 and the suitable for acting on the 34, of the needle pushers 35, and of the pushing rods 42a-42d same CaMS which also act on for needle selection and of the need upper cylinder Figures 2 and S lot 82 i S of t h e must take upper skirt comprise a heels of the of the dur..imy and 45. These the corresponding for driving the les inside their slots on the These cams are 1221:_22 known, and therefore disclosed in detail. It is enough to stress, purposes of understanding, that in the lower lifting cams 83 and 84 and a sinking cam 85 are for driving the heels 41 of the needle pushers define, together with counter-cams, a working for said heels 41, which, however - if by the relevant selectors 34, a r e so that their heel 41 cannot be engaged by the-lifting cam 83 run along the horizontal resting track X2. in a sip...ilar way, lifting cams 86 and 87 and a sinking can, 88 are provided for the heels 42 of the dummy sliders 36, and these caims too define, together with related counter-cams, a working track Yl flor the heels 42 of the dummy sliders 36, and a substantially horizontal resting track Y2.

In the upper skirt 11 two movable cams Cl and C2 are provided, which can be respectively controlled by the actuators AC1 and AC2; but these cams are not u--ed for the selection of, and for driving the yarn change, and therefore they are not disclosed in detail.

Also provided are a lifting cam 89, with relevant counter-cams, which cam has a horizontal groove 90, as well as sinking cams 91 and 92, and such cams define a track Z1 for the heels 43 of the pushing rods 42a-42d, which track runs through the groove 90 of the cam 89.

A 1 s o the longer heel 46 of the hook-driving pushing rod runs along this track Z1, but, by being longer than the heels 43, it is lifted by the portion 93 of the lifting cam 89, running, i"n this part of the path, along a diverted track Z2 branching off the track Z1.

The device herein disclosed operates as follows.

Let us suppose that, at a detemined revolution of the machine, and at a certain yarn feed., it is required that the yarn guide 58a of the relevant yarn selec-tor apparatus 15 is turned to operating. In order to obtain that, the computer CAM sends signals of de-energization to the electromagnets 80 of the actuators 13 and 14 located in the yarn feed point to which the concerned yarn selector apparatus belongs, and precisely the 215 24.

electromagnets 80, which level of the heel 37 of the the slot 24 of the lower cylinder 21 electromagnets 80 are de-energized, are lifted and the selector 34 interior of the cylinder 21, relevant needle pusher are suitable for acting at the selector 34 provided inside in as much as said the relevant levers 16 remains extracted frori the keeping the heel 41 of the 35 in engagement with the cams 83 and 84 of the lower skirt 10 to run along the track Xl. In such way, the heel 42 of the relevant dummy slider 36 enters the track Y1 (see Figures 2 and 3), and the pushing rod 42a provided inside the slot 29 of the uppet. cylinder 22 with its short heel 43 is lifted from its low position by the cam 89, and is caused to run the track Z1. Along the horizontal portion of the corresponding to the groove 90 of the cam 89, the upper heel 44a of the pushing rod 42a is at the same height as of the lever 49, and pushes outwards the same lever 49 (see Figures 4 and 7), whose selection heel 54 keeps the upper portion of the yarn guide 58a to b.e turned to operating pushed towards the outside of the cylinder (see also"Figure 10). The lever 49 keeps pushed outwards the upper portion of the yarn guide 58a, until the inclined plane 68a of the thrust cam 68 pushes it to operating.

to the turning to operating of the the computer CAM sends a signal for too. In fact, when the yarn, i.e., the yarn guide, is changed, the intervention of the hook must always be associated.

The computer CAM sends de-energization signals to the electromagnets 80 of the actuators. 13 and 14 located a 1 o n 9 p a t h downwards said yarn qui.de, turning Simultaneously yarn guide 58a, actuatina the hook 71 25.

at the yarn feed point to which the yarn selector apparatus 15 belongs, whose- yarn guide is turned to operating, and namely those electronagnets 80 Which, through respective levers 16, are suitable for acting at the level of the heel 37 of the selector' 34 provided inside the slot 28 of the lower cylinder 21 which is associated with the drive of the hook 71. The selector, and the relevant interior of the cylinder, the heel 41 of pusher enters the track Xl, and the heel needle pusher remain extracted from the the needle 42 of the relevant dummy slider 36 enters the track Y1. As a consequencee, the pushing rod 45 operating inside the slot 33 of the upper cylinder 22 is lifted from its low position, and enters the track Z1, but, in as much as such a pushing rod 45 has a longer heel 46, it runs along the diverted track Z2. The slopes of the cams 89 and 93 lift the pushing rod 45, and then, through the bell crank make the hook 71 move outwards (see Figure 6), whilst hook return inwards 74, the cams 91 and 92 make the same again (see Figure 5).

For exemplifying. purposes, the change described between the yarn guide 58a and the yarn 58b of a yarn selector apparatus 15. With the yarn 58b of the yarn selector apparatuses, the slot 25 lower cylinder, and the slot 30 of the upper cylinde associated, inside which the pushing rod 42b with 44b is provided.

If we remind that in order to turn the yarn guide 58a to operating, as hereinabove disclosed, the electromagnets 80 of the actuators 13 and 14 suitable for acting on the selection heel 37 of the selector 34 s now guide guides of th.e r are hee 1 26.

associated with energized, it yarn guide 58a to the computer sai sai.d yarn guide 58a had to be dederives that, in order to turn the same not-operating, it is now required that suitable excitation signals to CAM sends d electromagnets.

Furthermore, to the contrary of the yarn guide 58a, in order to turn to operating the other yarn guides 58b 58d of the yarn selector apparatuses, the electromagnets of the actuators 13 and 14 destined to act on the selectors 34 associated with these other yarn guides must be energized. The reason for this different height p u s h i n 9 position stated.

the yarn all of the yarn too takes place de-energized, to case a blackout is running.

Going back to the description of the change between the yarn guides 58a and 58b of a y arn selector apparatus, it appears now evident that all the electromagnets 80 of

13 and 14 w i t h rods r e 1 The purposE guide t o t h e o f t h e i r at which the heels 44b-44d 42b-42d are, when they. are in atively to the levers 50-52, as of this difference is of causing both 58a of the yarn selector apparatuses of feed, and the hook 71, whose with the respective electromagnets be automatically turned to in power supply occurs while t h e low hereinabove s e 1 e c t i o n being operating, in the machine the actuators 34 In associated through the yarn guides 58a and 58b such way, the respective selectors 34 return their slots 24 and 25 of the lower cylinder pushers 35 renot engaging the Xl, but remain selectors excited. back inside 21, and also make the -relevant needle enter, so that the heels 41 thereof, by lifting cam 83, do not enter the track relevant must -be 27.

inside the low track X2 (see Figure 2). Therefore, also the relevant dummy sliders 36 inside the slots 24 and 25 do not enter, with their heels 42, the track Y1, but remain inside the low track Y2. As a consequence, also the pusher rods 42a and 42b do not enter wih their heels 43 the track Z1, but rem ain inside the low track Z3.

In as much as the pusher rod 42a associated i..,ith the yarn guide 58a to be turned to not-operating remains in i t s remains inactive, linder 22 (opposite a consequence, due on the yarn guide pushed towards the its heel 66 to be the return cam 69 upwards, and therefore low position, the relevant lever 49 rotated towards the interior of the cy position to that of Figure 7), and, as to the effect of the spring 64 acting 58a, the upper portion thereof is interior of the cylinder, enabling engaged by the inclined plane 69a of which moves the yarn guide 58a turns it to not operating.

in as much as also the pusher rod 42b associated with the yarn guide 58b remains in its low position, the heel 44b of such pusher rod, by already being at the same level as of the lever 50, can push outwards said lever 50, whose selection heel 55 pushes the upper portion of the yarn guide 58b, towards the action of the relevant spring 64, so that t.he heel 65 of this yarn guide can be engaged by the inclined plane 68a of the thrust cam 68 which moves downwards, and therefore to its operating position, the yarn guide 58b.

It should be understood that also simultaneously with this yarn guide change, the hook must be actuated.

In the hereinabove disclosed example of practical embodiment, only one of the yarn guides belonging to each 28.

yarn selector apparatus is turned to operating by energizing the el ec -11)-n-,-,-,--ign4Itts associated W ith t h c actuators (in the herein disclosed case, the yarn guide 58a), whilst, in order to turn to operating all of the other yarn guides 58b to 58d, it is necessary to energize th-e associated electromagnets. This makes it possible, in case of a fortuit-ous blackout in power supply, to always have the machine fed by one yarn guide only of each yarn selector apparatus. Also the hook is simultaneously actuated, if so required.

From the above disclosure, it results clear flow, according to the present invention, for the selection end the drive of the yarn change, the same elements are substantially used, i..,hich are already present for the selection and drive of the needles, taking advantage of the region wherein, in place of a true knit-Led fabric, the selvedge is produced.

r 1 ol c - 1 1. Device for the sele-ction and the drive ofthe change of the yarn for the yarn guides of yarn selector apparatuses, each comprising a plurality of groups of, elements, each constituted by a movable yarn guide provided with two drive heels and subject to the action of elastic means, by a clamp and by a movable knife and a stationary knife, in a knitting machine having a first portion provided with a plurality of slots parallel to one another, inside which needles with relevant selectors with pattern heels. needle pushers and needle actuators are inserted, and a second portion bearing, for eac feed, besides selection means acting on the pattern of the selectors, as well as drive cams acting on needle pushers and needle actuators, one of sai select-ion apparatuses, with said first portio knitting machine or said second portion of machine being connected with drive means relative moti..on between said two portions, first portion bearing thrust and return suitable for acting on the drive heels of the yarn h -yarn h e e 1 s s a i d d yarn of the the knitting to cause a and with said cam means guides of the yarn selector apparatuses in order to push the yarn guides to their active position, and return them back to their inactive position, characterized in that the the inside determined slots of said first portion of machine, concerning the region of formation of selvedge of the knitted fabric, there are inserted, besides the selectors and the needle pushers, pushing rods, instead of relevant needles, which equipped with heels located at different heights, number of the slots inside which said pushing rods a 1 s o a r e t h e a r e on s a i d i n s t a 11 e d yarn selector movable guide of provided and selection means, be heels located at d inserted being equal to the number of the movable varn guides provided in each yarn selector apparatus, and' each slot being associated with one of said yarn guides, that second portion of the machine there arIC each associated with a yarn selector apparatus, sets of intermediate movable elements, wherein each set from them comprises as many movable elements as the movable yarns g.uides are, which are provided in appararus, each of b e i n a each said intermediate elements associated with a determinec all of the yarn selector apparatus with a selection tooth which is yarn es, and bcing suitable for acting on said associated yarn guide, said pushing rods, during the relative movement between said two portions of the machine, as a function of the position of said ugh their r e 1 a t e d order to one of the of the yarn of said elastic cam means borne the or to enable said heel to cooperate ing suitable for acting, thro ifferent heights, each on a intermediate movable element of said sets, in lead, by means of the drive heels of the a selector apparatues, means, to cooperate w said first portion of elastic means to Lead the with the return cam means.

2. Device according tha.t each of said pusher rods with a drive heel, with such pushing rods being all located being suitable for being Led to lifting cams and sinking intermediate elemeni ssociated yarn guide against the action ith the pusher the machine, other drive to claim 1, is furthermore characterized -in provided drive heels of all of at the same height, cooperate with relevant cams located in said second 1 1 the and i portion of the 3. D e v i c e that the drive height as to be sinking cams when on the pattern selectors the associated selection 4. Device according to claim 3, characterized in that the selection means the selectors are constit which are actuatable by e electromagnets being levers are not active on 5. Device according that the pushing guides of the yarn sel destined to act on the element at such a height, as to intermediate mobile element in energizing of the electromagnet acting relevant selection lever on the pattern relevant sclector, whilst the other associated with the other yarn guides selector apparatuses have their heel the relevant intermediate mobile element at led to act on said intermediate mobile of the according to claim 2, characterized heels of the Pushing rods are at such led to cooperate with said lifting and heels of the relevant means are not active.

i r; a 1 acting on the pattern heels of uted by small selection levers, lectromagnets, and that with the de-energized, the relevant selection the selector pattern to claim 4, rod associated with ector apparatuses relevant h e e 1 s. characterized in one of the yarn has its heel mobi le t h i s det h e t h e rods intermediate be led to act on consequence of the through h e e L of pushing of the yarn destined to act on such heiahts as to be elements because excitation of the electromagnets act.ing through the relevant selection levers on the pattern heel of the relevant selectors.

6. Device according to claim 1. in a circular knitting machine whose first portion is constituted by two mutually superimposed cylinders and 3 01 whose second portion is constituted by relevant skirts surrounding said cyinders, wherein the yarn selector apparatuses are positioned with their yarn guides being vertical, and a hook is provided, which is mounted in such a way as to be driven to horizontally slide on a support integral with the upper cylinder, said slots being provided both on the lower cylinder and on the upper cylinder and being lined up to one another, characterized in that said pushing rods are housed inside the slots of the upper cylinder, whilst inside the corresponding slots of the lower cylinder said selectors, needle pushers and needle actuators are provided, that inside further lined-up slots of the upper cylinder and of the lower cylinder, relevant to the region of selvedge formation, elements are housed which carry out the selection and the drive of said hook, said elements comprising, inside the slot of the lower cylinder, a selector with a pattern heel which is located at a height different from the heights at which the-pattern heels of the other selectors are located, a needle pusher and a needle actuator, and, inside the slot of the upper cylinder. a drive pushing rod which is operatively connected with the hook, in order to cause, in consequence of vertical movements inside -said slot, horizontal outwards and inwards movements of the hook, said pushing rod being provided with a drive heel whi ch is at the same height as of the drive heels of the other pushing rods, but is longer than these latter, suitable for being led to cooperate with said lifting and sinking cams provided in the said second portion of the machine, and with a further lifting cam, which does not interfere 33 with the shorter drive heels of the other pushing rods.

7. Device according to claim 6, characterized in that said drive heel of the hook is at such a level as to be Led to cooperate with said cams when on the pattern heel of the relevant selector the associated selection means, in particular the selection lever actuated by, a relevant electromagnet, do not act.

8. Device according to claim 6, characterized in that associated with the hook an unhooking lever is provided, which too is guided inside the support of the hook., and that by means of the mutual engagement of these two latter elements, the unhooking Lever is automatically made rotate by the hook in order to disengage the yarn f rom t h e book during the f i na step of t h e inwards return stroke of this Latter.

Claims (1)

1. 9. Device according to Clain,' 1, characterized in that at ea.ch yarn feed

   point of the machine, for each selector associated with a yarn guide or with the hook having a pattern heel at different heights, two distinct selection means are provided in succession.

   10. Device according to claim 4, characterized in that the energizing and de-energizing of the electromagnets is 'commanded by signals emitted by a computer on the basis of the processing of information received from, a pattern analyser and an encoder.

   11. Your change selection and drive device constructed and arranged to operate substantially as hereinbefore described with reference to and as illustrated in the'accompanying drawings.

   Publihhed 1988 at The Patent Office, State House, 6W1 HolboM London WC1R 4Tp. purther copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington,Rent BR5 3RD. Printed by Multiplex techniques ltd, St Mary Cray, Kent. Con. 1187.