US3167938A - Method for narrowing plain stitch or rib fabric on a flat knitting machine - Google Patents

Description

3,167,938 7 B FABRIC Feb. 2, 1965 F. SEILER METHOD FOR NARROWING PLAIN STITCH 0R R ON A FLAT KNITTING MACHINE 4 Sheets-Sheet 2 Filed Aug. 20, 1962 H MKHIWAIIIIHHHHHH HH/H HAHH HHHHHH /MHHH /NVEN OR FRITZ S ILER Feb. 2, 1965 F. SEILER 3,167,938

METHOD FOR RROW .PLAIN STI 0R RIB FABRIC A FL KNITTING M INE Filed Aug. 20, 1962 4 Sheets-Sheet 3 INVENTOR FRITZ SE/LER Feb. 2, 1965 F. SEILER 3,167,938

METHOD FOR NARROWING PLAIN suwcu OR RIB FABRIC ON A FLAT KNITTING MACHINE Filed Aug. 20, 1962 4 Sheets-Sheet 4 iii /N\/ENTOR FFQI'TZ SEILER United States Patent 3,167,938 METHOD FOR NARROWLNG PLAHN STITCH 0R RIB FABRHZ ON A FLAT KNITTENG MACHINE Fritz Seiler, Corcelles, Neuchatel, Switzerland, assignor to Edouard Dubied et Cie. (Socit Anonyme), Neuchatel, Switzerland Filed Aug. 20, 1962, Ser. No. 217,822 Claims priority, application Switzerland, Aug. 18, 1961, 9,730/61 3 Claims. (Cl. 66-70) Generally the knitted fabrics destined to garments such as for example costumes, coats, vests, sweaters etc., are made of a certain number of distinct parts consisting of individually shaped pieces, namely the front piece, the back, the sleeves, collar etc. These distinct parts are assembled in the garment industry so as to form complete knitted articles.

The shaping of the parts to the desired form is generally made by subsequent narrowings and Widenings of stitches in the appropriate number and sequence.

The classical principle of the widenings, i.e. of the stepwise increasing of the width of a knitted piece, simply consists in adding, during the knitting operation, in the desired number and sequence further marginal needles in addition to those already carrying stitches. Since such methods are very well known and in practical use for a rather long time no particularly detailed description thereof will be given here.

On the other hand, the narrowings, by means of which it is intended to obtain a knitted fabric of decreasing width, cannot be obtained in such simple manner. As is easily understood the stitches to be narrowed cannot simply be knocked over without danger of formation of ladders susceptible of destroying the knitting. It is necessary to secure in any appropriate manner these narrowed stitches to the piece. The most direct and at the same time the cleanest method therefor consists in a lateral displacement of the marginal stitches to be narrowed in direction towards the middle of the piece on the same needle bed and in longitudinal direction thereof.

Several different methods have been proposed and used in practice for such displacement of stitches.

The most primitive one is the method according to which by means of a narrowing finger the stitch to be displaced is seized, removed from its needle and transmitted to another for example to the adjacent needle. It is obvious that such manual narrowing cannot be used in automatic knitting.

Therefor automatic narrowing fingers have been in vented which mechanically copy the different movements and operations heretofore made by hand. The devices used to this end have the great disadvantage that they are very cumbersome, sensitive, expensive, slow and not reliable and moreover that they hinder the visibility and accessibility of important machine parts.

Another group of methods for narrowing makes use of particular intermediate transfer tools such as hooks, forks, pincers, levers, jacks etc. intended to seize the stitches to be narrowed, to displace them onto an adjacent needle and to release them. Such auxiliary elements are either placed immediately in the needle grooves preferably superposed to the needles for example in form of transfer jacks of the type which, during the transfer operation, is lifted by a boss on the needle back and then laterally deflected, such as is disclosed in Swiss Patent No. 217,204 to H. Stoll 8: Co.; or in form of stitch forks adapted to cooperate with special needles the shafts of which on both sides comprise means for spreading the stitches, such as is disclosed in Swiss Patent No. 160,152 to Schaifhauser Strickmaschinenfabrik. According to other proposals the auxiliary elements are placed above the usual needle beds either in a clamping rail in the case of resilient transfer jacks with seizing beaks, such as is disclosed in German Patent No. 687,091 to Walter & Co.; or on two parallel circular shafts in the case of pivot levers with seizing hooks, such as is disclosed in British Patent No. 910,885 to Battistini and Jahn; or else in a laterally displaceable housing in the case of vertically reciprocable transfer hooks, such as is disclosed in British Patent No. 846,636 to R. Stoll et al. and British Patent No. 448,795 to Imon; or still else in a support extending over the whole length of the needle bed in the case of sliding jacks with pivotable beak head or pivotable seizing beaks, such as is disclosed in French Patent No. 1,222,011 to Universal Maschinenfabrik G.m.b.H.; on slide pieces displaceable by cables, such as is disclosed in French Patent No. 847,282 to Parisot; of tiltable and displaceable narrowing fingers with recesses, such as is disclosed in Swiss Patent No. 257,993 to Rohr; of arc-shaped narrowing jacks displaceable in longitudinal direction and pivotable about a ball joint comprising a channel-shaped downwardly open seizing beak, such as is disclosed in French Patent No. 908,976 to Etablissements Henri Thibord, etc.

Finally the transfer tools may also be lodged in separate small auxiliary beds arranged above the needle beds for example in the case of slidable transfer jacks perpendicularly bent downwardly and having an inwardly bent beak, such as is disclosed in German Patent No. 716,768 to Seyfert & Donner, or of transfer hooks sliding in angular direction with respect to the longitudinal extension of the needle and having a beak open on one side, such as is disclosed in British Patent No. 409,243 to Lunke, or of other similar auxiliary elements of similar form and op eration, such as is disclosed in French Patent No. 1,256,- 807 to Bergamaschi and Goisis.

All these transfer tools may be associated either with each separate needle over the whole needle bed length or they may be associated with the marginal needles only. The stitch transfer in order to obtain a narrowing may further be effected by means of an appropriate displacement of the needle bed or of the tool support either immediately from the stitch transfer needle to the adjacent needle in the same bed or first onto a needle of the opposite bed and then back again to the adjacent needle of the first bed. Thus, US. Patent No. 2,374,758 to Korber discloses a method for narrowing by the transfer of the marginal stitches wherein the needle beds are racked before the end of each travel of the carriage.

As is easily understood all these known methods, while effecting the desired operation, are rather complicated and cumbersome and consequently reduce the efiiciency and the output of the machine. Further they contribute more or less to an additional wear of the transfer stitch owing to the repeated change of direction and tension to which the stitch or stitches are submitted. Finally it is known in the art that the transfer of the marginal stitches always presents increased difficulties in view of the inclined position of these stitches due to the transverse tension in the fabric.

It is a prime object of the present invention to remove all these disadvantages.

To this end the invention contemplates a method for narrowing knitted goods of plain or rib stitches on a flat knitting machine, by the transfer of determined stitches and fastening thereof to adjacent stitches, comprising the steps of displacing laterally in direction towards the middle of the fabric one of the two groups of sittches forming in the fabric a marginal zone with excessively inclined extension of the stitches owing to the transverse tension in the fabric, or both of such groups of stitches at both margins of the fabric simultaneously, and of hereafter fastening the innermost stitch of this group or of by displacing the said auxiliary bed parallel tothe main beds.

The present invention further contemplates an appara- I tus for carrying .out such method on a flat knitting machine having rnain needle beds in standard arrangement, which apparatus comprises small auxiliary needle beds arranged above the main needle beds the latter comprising particular needles adapted to receive the stitches of the groups to be displaced and further comprising means for fastening an outermost stitch on the auxiliary needle bed to a needle of the main bed.

The accompanying drawings illustrate partly diagrammatically the narrowing method to be described in more detail hereafter, as well as the apparatus for carrying out such method. Thereby the views are given by way of example only, since other types of, knitting and other simultaneous numbers or sequences of narrowing may be the main needle beds, whereby .each of such auxiliary beds may be pivoted about an axis 45 extending over the whole length of the machine. Reference numeral 46 designatesthe heel of a standard knitting needle of the auxiliary needle bed in working position and numeral 47 designates an identical needle but in rest position. Reference numeral 48designa'tes the fabric descending between the two needlebeds and reference numeral 49designates the knock over comb of the main needle bed 41.

The narrowing is effected as follows: At the beginning of the narrowed portion of a fabric knitted in plain stitches on one bed (FIGURES 1-5) all stitches are for example on the rear bed (FIGURE. 1). The needles carrying these stitches are, however, not. lodged allin the rear main bed 41'but a certain number thereof (in the represented example six of them on each side, i.e. the needle groups 9-14 and 17-22) are arranged in the small auxiliary beds 44.

Assuming that the machine carriage 3, 4 is at the right side at this'very moment and is movedover the needle beds in direction of the arrow in FIGURE 2 from the 7 right to .the left, the stitches of the needles 23 and 15 thought of without departingfrom the invention. Also constructive details of the auxiliary needle bed and of V the guiding thereof may be modified without departing from the invention. In the drawings;

FIGURES 1-5 illustrate diagrammatically a plain stitch fabric on one bed with the individual subsequent phases of symmetrical narrowings on both margins of the fabric.

FIGURES 6-10 illustrate in an analogous manner diagrams of stitches of 1 and 1 ribfabric on two beds also showing the subsequent stitch rows during a symmetrical narrowing of the fabric on both margins.

FIGURE 11 illustrates diagrammatically a knitted fabric having narrowings stepped symmetrically towards the middle.

FIGURE 12 shows, with one side broken away, a cross-section of the main and auxiliary needle beds with their respective needles in knitting position.

FIGURE 13 shows a section similar to that of FIG-' URE 12 but with the auxiliary needle beds in upwardly pivoted position for lateral displacement, and

FIGURE 14 illustrates a partial top view of a main needle bed and an auxiliary needle bed with the pivot axis thereof.

Referring now to the drawings, in FIGURES 1-5 reference numeral 1 designates a row of plain stitches on one bed for example on the rear needle bed, while in FIG- URES 6-10 reference numeral 2 designates l and 1 rib stitches on two beds. Reference numerals 3 and 4 designate the diagrammatically represented rear and forward cam plate respectively, of known construction; the supports for the transfer cam parts are designated by 5 and 6 respectively, for the left rearward and forward pant and by 7 and 8, respectively, for the right rear and forward parts. Finally references 9-16 and 17-24, respectively, designate groups of a certain width of marginal needles of the rear ward needle bed.

The corresponding needle groups of the forward bed are designated by reference numerals 25-32 and 33-40, respectively. Thesarne reference'numerals, viz: 9-16 and 17-24, respectively, exist in FIGURE 11 in which they designate the same needles for the stitch diagrams of FIGURES 6-10. main needle beds of the machine is designated by 41, whereby the opposite bed, arranged in known manner symmetrically with respect to thelongitudinal axis 'of the machine, is absolutely analogous. 42 designates the heel of a transfer needle in working In FIGURE 12 one of the two Reference numeralof the rear main bed will be transferred to the needles 39 and 31, respectively, of the forward main bed by the well known direct transverse transferringxfor which the machine is built. To this end the said needles 23 and 15. have been selected previous .to such operation by a well known selecting device which does not form subject of the present invention and therefor shall not be describedin detail here, in such'manner that they cooperate also inwell known manner with the transfer cam parts 7, 8. The method of transferring stitches referred to in this paragraph is more fully described in German Patent No. 692,981 to Edouard Dubied & Oie Socit Anonyme, U.S. Patent No. 2,575,365 to Sirrnay and my copending application Serial No. 285,323 which was filed on June 4, 1963.

At the return of the .carriage. ,3, 4 (FIGURE 3) the stitch transferring is effected in opposite direction, i.e. the stitches on the needles 31 and 39 of the forward main bed are again transferred by the well known method of needle to needle transfer onto the needles 16 and 24, respectively, of the rear main bed.

In this manner the needles 15 and 23. of the rear main bed have been liberated from their respective stitch and to the right (FIGURE 3) the two auxiliary beds 44, ar-

a one needle gauge or cut.

position, reference numeral .43 the heel of an analogous ranged at the ends of the rear main bed 41 and above thereof, are displaced simultaneously to the middle of the machine each about an amount. corresponding to Thereby the needle groups in the said auxiliary beds, namely the needles 9-14 and 17-22, respectively, carrying the marginal stitches have approached each other about two gauges resulting in a correspondingreduction of the widthof the fabric without necessitating a handling of the outermost marginal stitches 9, 17 which are difficult to transfer in view of their inclined position. Simultaneously'the innermost needles 14 and 22 of the auxiliarybeds have taken the place of the liberated needles 15, 23 of the rear main bed which have been put into rest position (FIGURE 5) The plain stitch row 1 on one bed is thus restored but reduced on both sides about one needle and the knitting may be continued in this condition to the next narrowing which is effected in the same way as has just been described.

In the case of a 1 and 1 ribfabric on twobeds (FIG URES 6-10) the. narrowing operation is principally the same as describedwith respect to the preceding example, except for the modifications resulting fro-m the different type ofknitting. The sequence of the operation-is the following: Starting from one row of 1 and 1 rib knitting, in which. the stitches 2 alternately engage all needles of both main beds (FIGURE 6), as in the preceding example a group of standard knitting needles on both margins of the fabric are arranged as well on the rear as also on the front machine side in small auxiliary needle beds 44 instead of being lodged in the main beds 41. Upon the carriage stroke from the right to the left there is effected a transfer of stitches from the rear needles 23 and 15 onto the front needles 39 and 31, by means of the cam parts 7 and 8 (FIGURE 7). Upon return of the carriage from the left to the right there is effected a transfer of the stitches from needles 31 to needle 16 and from needle 39 to needle 24, respectively (FIGURE 8). The needles liberated from their stitches in this manner, namely the rear needles 15 and 23 and the front needles 31 and 39 are now put out of operation (FIG- URE 9). Upon termination of the carriage stroke from left to right the four small auxiliary beds 44 are simultaneously displaced each about one gauge in direction to the middle of the fabric, whereby the needles 14, 3t and 22, 38 take the place of the withdrawn needles 15, 31 and 23, 3? respectively (FIGURE The remaining unchanged row of l and 1 rib stitches is thus restored but reduced in its width at each margin about one front and one rear needle. Thereby again the actual inclined marginal stitches have remained untouched. A similar narrowing cycle may start again either immediately or after a certain number of complete 1 and 1 ribs rows.

From the foregoing description of the narrowing operation it appears that the narrowings are not limited to one simultaneous gauge but may include several needles of one row. Further the sequence of these narrowings may be modified at will and the method may also be applied to knitting types different from the two cited examples.

The operation of the apparatus for carrying out the described method is the following: The core of the machine, i.e. the totality of the stitch forming elements consists in accordance with standard construction of a pair of needle beds 41 in roof-like arrangement comprising independent knitting and transfer needles. In contradistinction, however, to the standard construction of these beds and needles in which the same needle type is equally distributed in analogous grooves over the whole length of the bed of the machine adapted to effectively perform the described narrowing method is preferably provided with special beds and needles having a strictly symmetrical arrangement with respect to the middle of the machine. In other words the total length of the active part of each of the two needle beds is divided into two clearly distinctive halves one of which being a mirror arrangement of the other. Such a special arrangement is described in more detail in my copending application Serial No. 285,323 which was filed on June 4, 1963.

In accordance with the heretofore given explanation of the narrowing method the small'auxiliary needle beds are adapted on the one hand to receive a certain number of needles at both margins of the fabric and on the other hand to be laterally slidable so as to be able to bring their innermost needle or needles to the position of that needle or these needles of the main beds which has or have just been liberated from its stitch or their stitches. In order to make possible such lateral displacement in longitudinal direction of the main beds 41, the auxiliary beds 44 must be guided and arranged independently and above of the main beds in such position and direction that the crossing of their needle hooks in forward position takes place at the same point of intersection as that of the main bed needles. Since the bearing, guiding and displacing of the auxiliary beds as mentioned does not present any particular difficulty or require special features but may, on the contrary, be realized mechanically by anybody skilled in the art, a more detailed description and representation of such means is dispensed with. Only the axis 45 is shown which serves as well as suspending and guiding member as also as pivot point for the auxiliary bed 44.

This possibility of pivoting the auxiliary bed 44 is necessary in order to make possible lateral displacement thereof without having its needles which shall take the place of the liberated needles of the main bed put in rest position abutting during this operation against the teeth 49 of the knock over comb.

The complete cycle of lateral displacement consists of the following three phases: pivotment of the auxiliary needle bed 44 about the axle 45 into an upper position affording free passage of the auxiliary needles above the knock over comb 49. Then actual lateral displacement about one or several gauges and finally lowering of the auxiliary bed by pivotal movement in opposite direction. These mentioned pivotal and translatory movements may be effected either independently from each other or in combination, whereby of course both movements are automatically controlled and initiated at the desired moment by the central control mechanism for the automatic machine operation.

I claim:

1. A method for narrowing a fabric on a flat knitting machine by the transfer of determined stitches carried by the outermost needles of at least one side of a predetermined middle zone of the fabric, comprising the steps of arranging said needles at a determined distance from the margins of the fabric, transferring stitches from one needle bed to another,thereby releasing the stitches from said outermost needles, each transfer of stitches being followed by a lateral displacement toward said middle zone of at least one group of marginal stitches outside said middle zone which are not transferred, said lateral displacement causing the innermost needle of said group of marginal stitches to approach the needle from which the outermost stitch is released, and thereafter putting the latter needle is a rest position with said innermost needle of said group of marginal stitches taking its place in the middle zone of the fabric.

2. A method as claimed in claim 1 further characterized by suspending each of the groups of marginal stitches to be displaced from needles lodged in an auxiliary needle bed arranged above the main needle beds; and wherein said causing of the innermost needle to approach the needle from which the outermost stitch is released is effected by laterally displacing said auxiliary bed parallel to the main needle beds.

3. A method as claimed in claim 1 wherein the transfer of the stitches from one needle bed to the other is effected in both directions directly from needle to needle without racking the needle beds.

References Cited by the Examiner UNITED STATES PATENTS 2,374,758 5/45 Korbar 6670 RUSSELL C. MADER, Primary Examiner.

DONALD W. PARKER, Examiner.

Claims (1)

1. A METHOD OF NARROWING A FABRIC ON A FLAT KNITTING MACHINE BY THE TRANSFER OF DETERMINED STICHES CARRIED BY THE OUTERMOST NEEDLES OF AT LEAST ONE SIDE OF A PREDETERMINED MIDDLE ZONE OF THE FABRIC, COMPRISING THE STEPS OF ARRANGING SAID NEEDLES AT A PREDTERMINED DISTANCE FROM THE MARGINS OF THE FABRIC, TRANSFERRING STICTCHES FROM ONE NEEDLE BED TO ANOTHER, THEREBY RELEASING THE STITCHES FROM SAID OUTERMOST NEEDLES, EACH TRANSFER STITCHES BEING FOLLOWED BY A LATERAL DISPLACEMENT TOWARD SAID MIDDLE ZONE OF AT LEAST ONE GROUP OF MARGINAL STITCHES OUTSIDE SAID MIDDLE ZONE WHICH ARE NOT TRANSFERRED, SAID LATERAL DISPLACEMENT CAUSING THE INNERMOST NEEDLE OF SAID GROUP OF MARGINAL STITCHES TO APPROACH THE NEEDLE FROM WHICH THE OUTERMOST STITCHES IS RELEASED, AND THEREAFTER PUTTING THE LATTER NEEDLE IS A REST POSITION WITH SAID INNERMOST NEEDLE OF SAID GROUP OF MARGINAL STITCHES TAKING ITS PLACE IN THE MIDDLE ZONE OF THE FABRIC.

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