US3512377A

US3512377A - Patterning mechanism for circular knitting machines

Info

Publication number: US3512377A
Application number: US747892A
Authority: US
Inventors: Albert H Widdowson; Ernest L Farmer; Sidney C Savage
Original assignee: Wildt Mellor Bromley Ltd
Current assignee: Wildt Mellor Bromley Ltd
Priority date: 1967-07-28
Filing date: 1968-07-26
Publication date: 1970-05-19
Anticipated expiration: 1987-05-19
Also published as: DE1760972B2; DE1760972C3; DE1760972A1; FR1575188A; GB1160100A

Description

y 70 A. H. WIDDOWSON ETAL 3,512,377

PATTERNING MECHANISM FOR CIRCULAR KNITTING MACHINES Filed July 26, 1968 3 Sheets-Sheet 1 Fig.2.. I

.A. H. WIDDOWSON I ETAL I 3,512,377

May19, 1970 I PATTERNING MECHANISM FOR CIRCULAR KNITTINGMMJIIINES 3 Sheehs- Sheet 2 Filed July 26, 1968 May 19, 1970 A. H. WIDDOWSON ETAL 3,512,377

PATTERNING MECHANISM FOR CIRCULAR KNITTING MACHINES Filed July 26, 1968 3 Sheets-Sheet 3 United States Patent US. C]. 66-36 7 Claims ABSTRACT OF THE DISCLOSURE Needles in cylinder of circular knitting machine controlled by jacks with depending extensions and bottom butts. Extensions normally held out to enable butts to be acted upon by a jack raising cam. Extensions can be pressed in so that the bottom butts avoid cam. Fulcrumed pressers, in front of jack extensions, normally held with their lower endes swung outwardly and contrastingly formed upper ends swung inwardly. Electromagnets selectively influence upper ends of pressers, and are brought into operation selectively, under the influence of control means, to hold pressers with their upper and lower ends swung respectively outwards and inwards.

This invention appertains to circular knitting machines, and has reference exclusively to such machines of the kind in which each of a circular set of needles in a needle cylinder is arranged to be raised by a corresponding jack which is provided below and in the same needle trick or groove as the needle and is furnished with a depending extension having at its lower end a bottom butt.

In a circular knitting machine of this kind, the depending extension of each jack is normally held in an outward position, i.e. a position wherein its bottom butt is held protruding from the needle cylinder so as to be in the path of a jack raising cam whereby the jack and hence also the corresponding needle is raised to a desired height. However, whenever in such an arrangement the depending extension of a jack is pressed inwardly to withdraw its bottom butt into the cylinder, that butt, being buried and no longer protuberant, will fail to be acted upon by a jack raising cam as a consequence of which the corresponding needle will not be elevated to the aforementioned height.

Although there is no limitation in this respect, it is the intention to apply the invention to a machine of the kind concerned wherein the jack raising cam is a clearing cam located at a knitting station.

As well known to those acquainted with the art concerned, by providing patterning means in association with the set of jacks it is possible to secure by selection a condition, in advance of a jack raising cam, such that the depending extensions of some of the jacks are pressed in so that their bottom butts are withdrawn to miss the cam and the corresponding needles remain down, whereas the extensions of others of the jacks are permitted to be in their outward positions so that the relevant bottom butts protrude from the cylinder and are acted upon by the said cam as a result of which the corresponding needles will be elevated, e.g. to clear and take yarn for knitting.

Advantageously, in a circular knitting machine of the kind herein referred to, the jacks may be so-called spring jacks provided with depending extensions which are inherently resilient. In such a case, the depending extension 3,512,377 Patented May 19, 1970 of each jack is normally held, by virtue of its inherent resilience, in its outward position and is pressed inwardly (to withdraw its bottom butt into the cylinder) against this resilience. Consequently, whenever inward pressure on the depending extension is relieved, it automatically springs out into its normal position.

Alternatively, the jacks may be rocking jacks designed to be held by friction in the positions to which they are rocked. Thus, in this alternative case, cam means suitably arranged for action upon the jacks require to be provided for the purpose of rocking the jacks to project their nonresilient depending extensions into their normal outward positions.

The object of the present invention is to provide, in a circular knitting machine of the kind herein referred to, an improved, simple and eflicient form of patterning mechanism for selectively positioning the depending extensions of the jacks in advance of a jack raising cam.

According to this invention, there are provided, in front of the depending extensions of the jacks so as to be capable of acting thereupon, a corresponding set of suitably fulcrumed pressers which are normally held with their lower and upper ends swung outwardly and inwardly respectively, and for selectively influencing the .upper ends of desired pressers, which are contrastingly formed, there are provided presser-holding elements adapted to be brought into commission selectively, under the influence of control means, for the purpose of temporarily holding relevant ones of the pressers with their upper and lower ends swung respectively outwards and inward-s thereby causing the bottom butts of the corresponding jacks to be withdrawn suchwise as to miss the jack raising cam.

The pressers are fulcrumed at points intermediate their ends, and the idea is that the depending jack extensions shall normally be relied ,on to hold the lower ends of the pressers in their outer positions; hence, this condition is such that, normally, the upper ends of the pressers are swung backwards intocontact with the front edges of the jack extensions. But whenever a presserholding element is rendered operative and thus brought into commission, those pressers having formations disposed to be influenced thereby will be held with their upper ends outwards and their lower ends inwards to press in the corresponding jack extensions with the result already described.

In order that the invention may be more clearly understood and readily carried into practical effect, a specific example of the improved patterning means will now be described with reference to the accompanying drawings, wherein:

FIG. 1 is a vertical sectional view of so much of the head of a circular knitting machine of the rotary needle cylinder type as is necessary to illustrate the application of the invention thereto, the depending extension of the jack shown and the lower end of the corresponding fulcrummed presser being represented in their outer positions,

FIG. 2 is a detail vertical sectional view corresponding to a fragmentary part only of FIG. 1 showing the lower end of the said presser swung inwards to press in the depending extension of the underlying jack,

FIG. 3 is a fragmentary part-sectional plan view, as seen in the direction of the arrow A in FIG. 2, including a few of the pressers, two of the presser-holding elements and a presser operating cam used for a purpose hereinafter to be described,

FIG. 4 is an elevational view, in diagrammatic form, of the means provided in the machine for controlling the presser-holding elements in accordance with patterning requirements,

FIG. is a detail cross-sectional view, taken on the line BB of FIG. 4, of the tape unit included in the said controlling means,

FIG. 6 comprises a few of the pressers, shown in side elevation, and contrastingly formed by virtue of being furnished with upper butts at different heights, and

FIG. 7 is an end view, as seen in the direction of the arrow C in FIG. 1, of the bank of selectively activated presser-holding elements.

Referring to FIG. 1 it will be seen that the machine includes a rotary needle cylinder 1 formed peripherally with tricks or grooves 1a in each of which is accommodated a latch needle 2. The cylinder 1 is surrounded by a stationary annular shell or cam box 3 in which are mounted cams, such as 4 and 5, designed for action upon butts 2a on the needles for the purpose of operating the latter. The annular shell or cam box 3-is supported upon a fixed cam box plate 6.

Mainly below, and in the same trick or groove 1a as, each needle 2, there is provided a corresponding spring jack 7 for selectively raising the needle to clear, preparatory to knitting as and when required to do so. The upper end portion 7a of each spring jack contacts the back edge of the stem of the relevant needle 2 and is formed with a forwardly projecting shouldered portion, i.e. upper butt, 7b for engagement with the lower end of the said stern. Each such jack, moreover, has a depending inherently resilient spring extension 70 having at its lower extremity a bottom butt 7d. This extension is normally held, by virtue of its inherent resilience, in the outwardly sprung position illustrated in FIG. 1. With the said extension in this position, the bottom butt 7d of the jack 7 is held protruding from the needle cylinder 1 so as to be in the path of a jack raising cam 8 whereby the jack is raised to position the corresponding needle 2 at clearing height in advance of a stitch cam (not shown) at a knitting station. But whenever the depending resilient extension 70 of a spring jack 7 is pressed inwardly into the position shown in FIG. 2, to withdraw its bottom butt 7d into the cylinder 1, that butt is nolonger protuberant and thus fails to be acted upon by the jack raising cam 8; consequently the corresponding needle will not be elevated to clearing height.

The jack raising cam 8 is set in a rabbetted portion 9a of a ring 9 let into and carried by the fixed bed plate 10 of the machine.

In accordance with the characteristic feature of this invention, there is provided, in front of the depending spring extension 70 of each jack 7, a rocking presser 11 which is arranged to fulcrum about a pivot 12 located intermediate its upper and lower ends. Each such presser 11 is normally held, by the sprung out depending extension 70 of the corresponding spring jack, with its lower end swung outwardly and its upper end swung inwardly as illustrated in FIG. 1.

The upper ends of the fulcrumed pressers 11 are contrastingly formed by virtue of being provided with outwardly extending butts 11a contrasting, as between different pressers, by their heights on the presser stems. Thus,

referring to FIG. 6, it Will be appreciated that each of the circular set of pressers 11 provided right around the needle cylinder 1 may be, according to patterning requirements, of any one of the six contrasting forms designated af. The six different heights at which presser butts 11a are provided are designated h h respectively. The upper end of each presser may conveniently be initially formed with a full complement of frangible butts 11a arranged one above another, all but one of the butts being broken off. Merely for convenience in illustration, a full complement of such frangible butts 11a is shown in FIG. 1 and in FIG. 2, the condition in which all but one of the butts is broken off is depicted by full and dotted lines. Accordingly, in the illustrated arrangement, the circular set of pressers 11 have judiciously disposed butts 4 11a-one per presserlocated in a plurality of superimposed planes.

There is provided, in advance of the jack raising cam 8, a bank of superimposed presser-holding elements 13 the number of which corresponds to the number of butt planes h 'h To effect an economy in space, the elements 13 in the bank are, as shown more clearly in FIG. 7, relatively disposed in a staggered relationship. Moreover, and as depicted in FIG. 1, the presser-holding elements 13 are supported by the spaced limbs 14a of a bracket 14 of inverted U-form, this bracket being attached to the underside of the fixed cam box plate 6.

Whatever their form may be, the presser-holding elements 13 are adapted to be brought into commission selectively, under the influence of control means, for the purpose of holding selected ones of the pressers -11 with their upper ends swung outwards and their lower ends swung inwards as shown in FIG. 2. In the last mentioned figure, in fact, the single element 13 shown has been activated to hold a presser 11 by its butt 11a at the height h (compare FIG. 6).

Preferably, the presser-holding elements -13 consist of electro-magnets each comprising an elongated core 15 of magnetic material, e.g. soft iron, surrounded by a coil 16 of wire. The leading, i.e. operative, end of each core 15 is formed with a laterally extending portion 15a, these portions being arranged opposite to and adapted to attract and to hold the butts 11a provided on the upper ends of the pressers 11. As will be appreciated from a consideration of FIG. 7, the core portions 15a of the three left-hand electro-rnagnets 13 extend laterally to the right, whereas the corresponding core portions of the three relatively staggered right-hand electro-magnets similarly extend to the left, the two oppositely directed series of such portions being interleaved as shown. The extents of the laterally extending core portions 15acircumferentially of the machinedetermine the length of time pressers are held by energised electro-magnets, the period of temporary hold being sufiicient to enable pressed-in jack extension to miss the raising cam 8.

Signals for energising the electro-magnets selectively and at required times in accordance with patterning requirements may be controlled by or from a film unit or tape control of any appropriate character. Thus, in the particular example illustrated, the required signals are controlled by a film 17 arranged to run over an intermittently rotatable drum 18 having formed therein axial- 1y extending and circumferentially spaced parallel rows of holes =18a. There are six holes 18a in each such row to correspond with the six heights h h of presser butts 11a. An electric lamp L is disposed within the drum 1-8. The film is formed, at predetermined points only, with apertures 17a. Located adjacent to the control drum 18, respectively in line with the six longitudinally extending tracks of the holes 18a, is a series of six photo-electric cells .19 which are connected at '20 to an electronic control box 21 (see FIG. 4). Wires 22, encased in a cable 23, extend from this box and are connected to the coils 1 6 as depicted in FIG. 1. Thus, each time the drum =18 is racked round one space, an axial row of six of the holes 18a is brought into alignment with the six photo-electric cells 19. But only at those points where apertures 17a in the film 17 register with holes 18a in the drum 18, will light, emitted by the lamp L, be permitted to shine through on to the corresponding photo-electic cells 19. At unapertured points of the film, the underlying holes 18a of any particular axial row will be masked to prevent light reaching the corresponding cells. The arrangement is, of course, such that whenever light is permitted to fall on to a cell through a hole 18a and an aperture 17a registered therewith, a' signal will be generated, through electronic circuitry in the box 21, for energising the corresponding electro-magnet 13. Consequently, the upper ends of all of the fucrumed pressers 11 having butts 11a at the height or heights at which the energised electro-magnet or magnets is or are disposed will be temporarily held in their swung outward positions with the result already described. Jacks 7 corresponding to those pressers which are not so held by electro-magnets will be raised by the cam 8 as already explained herein.

According to another features of the invention, means are also provided to automatically press in the lower ends and swing out the upper ends of all of the pressers 11, and hence also press in all the jack extensions 7c seriatim, preparatory to needle selection and thus at a location immediately in advance of the jack raising cam 8. It will, therefore, be realised from the foregoing description that selected electromagnets 13 will thereupon be energised, at the dictates of the control means, so that relevant ones only of the pressers will be temporarily held in the positions to which they have just been turned to maintain the corresponding jack extensions in their pressed in positions, whilst the remaining jack extensions will be permitted to return to their normal sprung out positions. In this way the bottom butts 7d of certain of the jack extensions 70 will fail to be acted upon by the jack raising cam 8 whereas the bottom butts of the remaining jack extensions will be so acted upon.

The said means for automatically pressing the lower ends of the pressers and hence also the jack extensions inwardly preparatory to a selection may, as shown in FIGS. 1, 2 and 3 consist of butts 11b formed at the lower extremities of the pressers 11 and adapted to be acted upon by an operating cam 24 located immediately in advance of the bank of presser-holding elements 13.

Alternatively, the core 15 of each of the electromagnets 13 may be a peirnanent magnet capable of being de-energised by the coil 16 at the dictates of the control means. Thus in this case all of the pressers 11 will initially be held in the positions to which they are turned by the operating cam 24, and when predetermined permanent magnets are selectively de-energised, at the dictates of the control means, the upper ends of the corresponding pressers 11 will be released, thereby permitting the extensions of the corresponding jacks to return to their normal sprung out positions.

It is to be clearly understood that in the application of the invention, as is principally the intention, to a multi-feed circular knitting machine of the rotary needle cylinder type, there is a jack raising cam 8, a bank of the presser-holding elements 13 and a presser operating cam 24 all in advance of each feed. Thus, the ring 25 constitutes a common carrier for all of the operating cams 24, and the inner edge 25a of the said ring provides an annular abutment with which the depending extensions 7c of the spring jacks 7 make contact whenever they are permitted to spring outwardly: in other words, the ring 25 determines the outer position of these extensions.

We claim:

1. A circular knitting machine including a tricked needle cylinder; individually operable knitting needles in said tricks; needle-controlling jacks provided below and in the same tricks as said needles; and a jack raising cam below the jacks; each jack being provided with a depending extension which has a bottom butt at its lower end and is normally held in an outward position in which said bottom butt protrudes from the cylinder so as to be in the path of said jack raising cam for raising the corresponding needle to a desired height, but the depending extension being capable of being pressed inwardly to withdraw its bottom butt into the cylinder so that the butt will fail to be acted upon by the said cam and the needle will not be raised; wherein the improvement consists in the provision in the machine of a patterning mechanism for selectively positioning the depending extensions of the jacks in advance of the jack raising cam, said mechanism comprising, in combination; a set of pressers fulcrumed intermediate their ends and arranged in front of the depending extensions of the jacks for action thereupon at required times, said pressers being norm-ally held with their lower ends swung outwardly and their upper ends, which are contrastingly formed, swung inwardly; presserholding elements for selectively influencing the upper ends of desired pressers; means for activating said elements, and control means for so influencing said activating means as to bring the presser-holding elements into commission selectively whereby relevant pressers are temporarily held with their upper and lower ends swung respectively outwards and inwards to cause the bottom butts of the correspondingly jacks to be withdrawn to miss the jack raising cam.

2. A circular knitting machine according to claim 1, wherein the depending jack extensions normally function to hold the lower ends of the pressers in their outer positions.

3. A circular knitting machine according to claim 1, which includes means for automatically ipressing in the lower ends and swinging out the upper ends of all of the pressers suchwise as to press in all of the depending jack extensions seriatim, at a location immediately in advance of the jack raising cam, the arrangement being such that upon selected presser-holding elements then being brought into commission, at the dictates of the control means, relevant ones only of the pressers will be temporarily held in the positions to which they have just been turned to maintain the corresponding jack extensions in their pressed in positions, whilst the remaining jack extensions will be permitted to return to their normal outward positions.

4. A circular knitting machine according to claim 3, wherein the said means comprise butts which are provided at the lower ends of the pressers, and an operating cam located in advance of the presser-holding elements for action upon the said butts.

5. A circular knitting machine according to claim 1, wherein the upper ends of the fulcrumed pressers are contrastingly formed by virtue of being provided with outwardly extending butts contrasting, as between different pressers, by their heights on the presser stems, and there is provided, in advance of the jack raising cam, a bank of superimposed presser-holding elements the number of which corresponds to the number of butt planes.

6. A circular knitting machine according to claim 5, wherein the presser-holding elements consist of electromagnets each comprising a core and a surrounding coil, the said cores having portions arranged opposite to and adapted to attract and to temporarily hold the butts provided at the dilferent heights on the upper ends of the pressers.

7. A circular knitting machine according toclaim 6, which includes photo-electric cells from which are derived signals for selectively energising the electro-magnets; a lamp constituting a source of light for activating said cells; and, for controlling the shining of light onto the said cells, an intermittently rotatable drum formed with series of holes, one per cell, and a length of film which is passed around the drum and has therein prearranged light-transmitting points for registering with predetermined drum holes, according to patterning requirements.

References Cited UNITED STATES PATENTS 1,722,989 8/ 1929 Ames. 3,229,482 1/ 1966 Farmer 66-50 3,262,285 7/1966 Beguin et a1. 6650 3,283,540 11/1966 Levin.

FOREIGN PATENTS 28,439 5/ 1964 Germany. 1,449,339 6/ 1966 France. 1,005,522 9/ 1965 Great Britain.

WM. CARTER REYNOLDS, Primary Examiner