US2337102A - Apparatus for knitting mesh fabrics - Google Patents

Description

Dec.21, 1943. H. HARRIS APPARATUS FOR KNITTING MESH FABRICS Filed June 24, 1943 2 Sheets-Shegtl INVENTOR.

' H A RR IS HARRY X ATTORNEY.

Dec; 21, 1943. Q; 2,337,102

APPARATUS FOR KNITTING MESH FABRICS Filed June 24, 1943 2 Sheets-Sheet 2 Z7) v I 7 fipw 23 2 5 3/ a 20/9 2 066; mlslslzlslelelslslalslsmamslslslalimelimslilils' ms lsmsm umsmsmilemnsmmmmmm 25 IIIIHIIIHIIIIHHIIIHIHIIHJIIIHHHHIIIIIIIIIIHHI67 mm! mmm IIIHHHII[IHHHIIIIIIIIIHIllllllllll 68 000 0000 ooo oooc INVENTOR. 7 HARRY HARRIS ATTORNEY.

Patented Dec. 21, 1943 UNTED STATES PATENT OFFICE APPARATUS FOR KNITTING MESH FABRICS Harry Harris, Tuckerton, N. J.

Application June 24, 1943, Serial No. 492,039

3 Claims.

This invention relates to the art of flat knitting machines and more particularly to the type of fiat knitting machines known as Reading full fashioned machines employed in the simultaneous manufacture of a plurality of full fashioned stockings.

The main object of my invention is to provide for the production of open mesh or lace effects of one or more designs during the knitting of stocking blanks on full fashioned machines more rapidly and economically than possible with the special lace tackle mechanisms heretofore designed for this purpose and to knit the same at substantially the same speed used in knitting plain fabric. This object is attained through provision of simple and inexpensive means whereby the normal picot or ravel stop mechanism, with which modern full fashioned machines are ordinarily equipped, is converted into means suitable to the formation of open mesh or lace effects of various designs. The invention provides means whereby the cycle of operation of the picot bar in its loop transfer operation is changed in alternate transfer operations. The changing of the cycle of operations-of the picot bar is carried out by means placed on the main cam shaft of the machine and without any alteration of those parts of the machine at or above the needle bed. In other words the picot bar operates in the normal manner without any change of structure, the change being in the timing of the operation of the picot bar.

Normally in the loop transfer operation, the picot points dip to take and remove the loops from certain of the needles, rise, and move these loops outwardly, from the center of the machine, then dip and transfer the loops back to adjacent needles. In this invention, by special timing of the picot bar, the points move outwardly, from the center of the machine, dip to take and remove loops from the adjacent needles, rise and move these loops inwardly, toward the center of the machine, then dip and transfer the loops back to the certain needles. tion and the special operation of the picot bar take place in alternate transfer operations, or in any other desired sequence of transfer operations, so that the transferred loops may extend in one direction in certain courses and in the other direction in other courses in the stocking blank. A special cam on the main cam shaft which may be selectively brought into operation with the picot bar operating mechanism, under control of the pattern chain, provides for the change in timing operation of the picot bar.

The normal opera- Other objects and advantages of the invention will be apparent from the following detailed description taken in connection with the drawings in which:

Figure 1 shows a cross section of a full fashioned knitting machine embodying my invention;

Figure 2 is a front elevation of a portion of the upper part of the machine viewed as indicated by the arrows 2-2 in Figure 1;

Figure 3 is a detail view showing one position of the picot bar actuating means; and

Figure 4 is a front elevation of a portion of the lower part of the machine as indicated by the arrows 4-4 in Figure 1, and showing the pattern chain.

Referring now to Figures 1 and 2 of the drawings, the stitch transfer mechanism is indicated generally by the numeral I ll. As usual, the curved arms ll of this stitch transfer mechanism reach forwardly from a longitudinally extending horizontal rock shaft l2 supported in the rear of the machine, to which they are secured and about which they may turn, and the forward ends of the curved arms ll support the longitudinally extending rod 2|. The vertically extending links I3 are likewise secured at their upper ends to the rod 2 I, the links being pivotally secured at their lower ends to the arms [4 pivoted at l8 and having the rollers I! which are subject to certain of the rotary cams on the cam shaft l5, one of said cams being indicated at l6 in Figure 1. The means for shifting the cam shaft l 5 to the right, as viewed in Figure 4, is not illustrated inasmuch as it is well known in the art.

The rod 2| which is supported from the ends of the curved arms II, has secured thereto suspension bearing members 22 that afford sliding support to a pair of axially aligned rods 23 and 24, each extending over half of the needle sets of the machine. To these rods 23, 24 are respectively attached the picot bars or combs 25 and 26, each associated with one of the two needle sets 21, 28 in each knitting section of the machine. It will be understood that there is a picot comb for each needle set of the machine, although only two such sets ar shown in Figure 2. When not in use, the combs are swung upward about the rods 23, 24 so that their points rest against a flat horizontal bar 29 which overlies the rod 2| and which is secured in place by screws to upward extensions 39 of the bearing members 22. The usual wedge cam for shifting the rods 23, 24 concurrently in opposite directions against the action of springs I 9, I9 is shown at 3| in the drawings, it being secured to one end of the lever 32 fulcrumed for free rocking movement on the rod H. The springs I [9 on rods 23, 24, extend between stops 2%, 2t fastened in place on the rods and bearing members 22, so that the springs urge the rods toward each other and against the opposite faces of the wedge cam 3i.

Ordinarily in the formation of a picot edge or ravel stop course in the fabric, the wedge cam 3! is moved into action to separat the rod 23, 24 to effect shifting of all the picot combs of the machine, of which combs 25, 26 are shown, for transfer of fabric loops from alternate needles to adjacent needles of each needle group. Half the needle sets, of which one 28 is shown, have their loops transferred to the right and the other half, of which one 27 is shown, have their loops transferred to the left, viewing Figure 2. In the making of open or mesh work in the body of the stocking it is desirable that the loops, in recurrent transfer courses, be transferred in opposite directions in each stocking blank so that the blank will be knit straight and will not be twisted or knit on the bias as would result if the loops in each blank were always transferred in the same direction. To accomplish this result, I provide means for specially actuatin the wedge cam 35, which with the action of the stitch transfer mechanism provides means for selectively causing the loops to be transferred in each needle set in a direction opposite from the direction of the normal stitch transfer. Mounted with capacity for oscillatory movement on the shaft I2, is a motion translating element 38 whereto is pivotally connected at Stone end of ya curved thrust arm 50, the other end of which .ispivotally connected to an end of the aforementioned lever 32, the other end of which has thewedge cam 3i fastened thereto. Oscillatory movement takes place in the element 38 by means of therotary cams M, 42 on the cam shaft of the machine, which act selectively, as will be explained, upon a roller 53 fitted upon the lower extremity of a spring-pressed bell crank lever t5 fulcrumed on a fixed center 5'8, see Fig ure 1,the upper and generally horizontal arm of the bell crank lever 45 being coupled, by means of an adjustable link rod 41, with the motion transmitting. element'SS. A vertical rod-like stop member 48 is fastened to the back frame of the machine by any suitable mean and has the vertically adjustable head 59 underlying the horizontal portion of the bell crank 45 in order to limit the downward position of the same when influenced by the spring M. The adjustable head #19 is positioned sothat the roller it, when spring biased, just clears the normal circular idlelcam 53 on the cam shaft A5. The purpose of this is to reduce thefriction on the roller is when the same is shifted, by means to be explained, to a position in which cams 4? or 42 act on the same. The positioning of the roller is by the stop itfl does not interfere with the action of the cams ll and 42.

Secured by any suitable means to the lower front part of the machine frame is the clevis or U-shaped member bl having the rod 52 fastened in and extending across the open end of the arms of the clevis. A spring 53 on the rod 52 forces the bell crank lever fa l, which is journaled for rocking movement on the rod 52, to the right,

Figure .4, where the forked end .55 thereof, which engages in a reduced groove in the shoulder 55 of the roller 43, holds the roller 43 to the right on the stub shaft 51, the latter being secured to and extending from the end of the bell crank lever 65. Normally, when the machine is knitting plain fabric, the parts are in the position shown in Figure 4 and the picot mechanism is not actuated. When it is desired to actuate the picot bars in the normal fashion, the cam shaft it shifts to the right and causes the roller 3 to be actuated by the usual cam i, However, when it is desired to actuate the picot bars in the changed manner in accordance with my invention, I cause the roller 53 to be actuated by the cam 32 when the cam shaft i5 is shifted. This is done under the control of the rod 53, one end of which is journaled for rocking movement in and secured to the short end of the lever and the other end of which is fastened to the free end of lever 59, which is pivoted on a suitable machine upright. The rod 53 when moved to the left, Figure l, moves the lever 56 against the action of spring 53 and causes the forked end 55 thereof to move the roller @3 along the stub shaft 57 a distance sufficient to cause it to be engaged by the cam 42 when the cam shaft I 5 shifts. Th lever 59 has the raised nose portion 6b which may be engaged and moved by the buttons 62 on the usual chain El trained over the wheel 63 intermittently rotating on shaft fi l, the lever 59 thus drawin the rod 58 to the left, Figured, and actuating the lever Ed. The spring 53 returns the parts to the normal position of rest when. the buttons 62 are not active. The cam M is the normal picotloar actuating cam and the cam 432 is a duplicate of cam ti except that it is setsubstantially one hundred and eighty degrees (186) ahead of cam ll on the shaft H5.

The goperationof the machine will now be described. In the mesh work itis preferred that the machine knit two courses of plain fabric and then a third course knitted somewhat looser than thepreceding two courses, the third course having specified stitches transferred to adjacent needles. It is obvious that the number of plain courses between transferred courses may be varied asdesired and it is also obvious that the particular stitches to be transferred be varied, by omitting more or less of the picot points, to provide different mesh designs. When the third course has been knitted in the usual way, the cam shaft i5 is shifted endwise in the known manner so that the cams l6 and 4! thereon are moved into the planes of the rollers l1 and 63 respectively. The cam I6 is the first to become active and causes clipping of the stitch transferring or narrowing mechanism Hi so that the points of the combs 25 and 25 are brought into engagement with aligned needles of the groups 2'! and 28 to take the fabric loops therefrom. Then as the narrowing mechanism I8 is lifted, through continued rotation of the cam it and shaft l5, with the loops on the comb points, the cam A! becomes active in causing forward movementof the thrust arm to, through the interposed bell crank lever t5, the link 41, and the motion transmitting member 38, to swing the lever 32 counterclockwise about the rodZl, and the wedge cam Si is thereby caused to move downward from the position of Figure 3, to that of Figure 2, to spread the rods 23, 2t and the combs supported by them against the action of springs l9, l9 compressing and storing energy in them. The points of the combs are brought into alignment with individual needles of the groups 21, 28 adjacent those needles from which the loops were previously taken. This is followed by a seconddip of the narrowing mechanism If! under the influence of cam l6, so that the loop suspended on the points of the combs are placed on the above referred to adjacent needles of the groups El, 28. Then as the cam shaft continues to rotate, the lever 32 swings clockwise to the position of Figure 3 under the influence of the spring 24 through the interposed link 41, the members 38 and ill, the wedge cam 3i rising out of spreading contact with the rods 23, 24 which are then moved inwardly to normal position by the springs l9, l3, and the narrowing mechanism is raised to normal position. Following the course of transferred work, the cam shaft I5 is shifted back to normal position in the known manner and regular plain knitting proceeds for the required number of courses.

In the sixth course of knitting transferred loops are again desired and the cam shaft I5 is again shifted endwise, but this time, however, a button E2 on the 6! becomes active to move the rod 53 which in turn causes the lever i l to shift the roller 43 to the left, Figure 4, a short distance, so that the cams l5 and 62 are moved into the planes of the rollers I1 and 43 respectively. The cam 2 2 is the first to became active and causes forward movement of the thrust arm it, through the interposed bell crank lever 4-5, the link ll, and the motion transmitting member 38, to swing the lever 32 counterclockwise about the rod 2!, and the wedge cam 3! is thereby caused to move downward from the position of Figure 3, to that of Figure 2, to spread the rods 23, 24 and the empty combs supported by them against the action of springs i9, i9 compressing and storing energy in them. The points of the combs are thus brought into alignment with the individual needles of the groups 21, 23 to which the transfer was made during the first described operation. The cam It then becomes active and causes dipping of the narrowing mechanism It so that the points of the combs 25 and 26 are brought into engagement with aligned needles of the groups 21 and 28 to take the fabric loops therefrom. Then as the narrowing mechanism if! is lifted, through continued rotation of the cam l5 and shaft l5, with the loops on the comb points, the lever 32 swings clockwise to the position of Figure 3 under the influence of the spring 44 through the interposed link ll, the members 33 and it, the wedge cam 3i rising out of spreading contact with the rods 23, 2 3 which are then moved inwardly to normal position by the springs l9, E9, the points of the combs are thus brought into alignment with the individual needles of the groups 2?, 28

from which the transfer was made during the first described operation. This is followed by a second clip of the narrowing mechanism It under the influence of cam IS, so that the loops suspended on the points of the combs are placed on the above referred to needles of the groups 27, 28, and then the narrowing mechanism is raised to normal position. Following this course of transferred work, the cam shaft is again shifted back to normal position in the known manner and regular plain knitting again takes place for the reqin'red number of courses. Thus, by intermittent actuation of the narrowing mechanism and the picot bar mechanism, the latter alternately actuated by the cams ll and A2 in the manner explained, as the knitting proceeds, fabric loops are transferred first in one direction and then in the other direction, between selected adjacent needles of the needle groups. It will be understood that, by appropriate spacing of control buttons on the pattern chains controlling the shifting of the cam shaft l5 and the roller 43, the direction of the loop transfer may be selectively controlled to follow any desired pattern, for instance two courses of mesh stitches may be transferred first in one direction and then the following two courses of mesh stitches may be transferred in the opposite direction, all in a manner which will be understood by skilled knitters.

Due to the employment of the picot combs 25, 26, it is impracticable to fashion the fabric with the usual narrowing combs 65, 6B, which are shown in Figure 2 as being shifted to inactive position beyond opposite ends of the needle banks. 1, therefore, accomplish the fashioning of the mesh stockings solely by gradually decreasing and increasing the throw of the carriers (5?, 58, which feeds the yarns to the needles 21, 23. To do this, I disconnect the pawls that cooperate with the ratchet wheels of the narrowing screws and provide two oppositely cut pawl driven ratchet wheels for turning the screws controlling the yarn stops so that the stops may be moved inwardly or outwardly depending upon which wheel is being driven, their pawls being selectively controlled. In those portions of the stocking where mesh work is not desired, as in the Welt and a short distance below the same and in the toe, it is discontinued by the appropriate spacing of the control buttons on the pattern chains and if in these plain knit areas it is desired to do fashioning by transferring stitches in the usual manner, this may be done by lifting the picot bars to inactive position and connecting up the pawls which operate the ratchet wheels of the narrowing screws, the narrowing proceeding in the usual manner.

What is claimed as new and useful is:

1. In a knitting machine having a straight series of needles, narrowing mechanism, a picot point comb supported by the narrowing mechanism with capacity for endwise shifting along the series of needles to transfer fabric loops between certain spaced needles and adjacent needles incident to the dipping, lifting and clipping of the narrowing mechanism in the transfer operation, a cam shaft, a cam on the shaft for operating the narrowing mechanism, two cams on the shaft for shifting the picot point combs, means for shifting said cam shaft to bring said narrowing mechanism operating cam into operating position and to bring one or the other of said two point comb shifting cams into operating position, and means for selecting which of said two cams is brought into operating position, one of said two cams shifting the picot comb after the first but before the second dipping of the narrowing mechanism in the transfer of loops from the certain needles to the adjacent needles and the other of said two cams shifting the picot comb before the first dipping of the narrowing mechanism in the transfer of loops from the adjacent needles to the certain needles.

2. In a knitting machine having a straight series of needles, narrowing mechanism, a picot point comb supported by the narrowing mechanism with capacity for endwise shifting along the series of needles to transfer fabric loops between certain spaced needles and adjacent needles incident to the clipping, lifting and clipping of the narrowing mechanism, a cam shift, a cam on the shaft for operating the narrowing mechanism, two like cams on the cam shaft for shifting the picot point comb, said two cams being substantially 180 out of phase, means for shifting said cam shaft to bring said narrowing mechanism operating cam into operating position and to bring one or the other of said two point comb shifting cams into operating position, and means for selecting which of said two cams is brought into operating position, one of said two cams shifting the point comb to transfer fabric loops from the certain needles to the adjacent needles and the other of said two cams shifting the point comb to transfer fabric loops from the adjacent needles to the certain needles.

3. In a knitting machine having a straight series of needles, narrowing mechanism, a picot point comb supported by the narrowing mechanism with capacity for endwise shifting along the series of needles to transfer fabric loops between certain spaced needles and adjacent needles incident to the dipping, fting and dipping of the narrowing mechanism, a cam shaft, a cam on the shaft for operating the narrowing mechanism, two like cams on the cam shaft for shifting the picot point comb, said cams being substantially 180 ut of phase, a roller cam follower slidable on a stub shaft and interposed between said last mentioned cams and the picot point comb operating means, means for shifting said cam shaft to bring said narrowing mechanism operating cam into operating position and to bring one or the other of said two comb shifting cams into operating position, and pattern chain operated means for controlling the position of said roller cam follower on said stub shaft for selecting which of said two cams is brought into operating position, one of said two cams shifting the point comb to transfer fabric loops from the certain needles to the adjacent needles and the other of said two cams shifting the point comb to transfer fabric loops from the adjacent needles to the certain needles.

HARRY HARRIS.

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