DESIGNS ON PLAIN PURL STITCH MACHINES—AUTOMATIC JACQUARD TYPE—DETAILS OF
JACQUARD-DESIGNING ON JACQUARD MACHINE
FIGURES 64, 65 and 66 show some of the design effects which may be made
on the links and links system of knitting. Fig. 64 is a basket weave
design. To make this we will assume that the machine is set up, that is,
has work on it, with the carriage at the left end of the machine. Then
all the needles would be in the front plate. The back plate should be
racked to its last position to the right. The last working jack in the
back plate, left end, should be opposite the last needle in the front
plate, but in the right end of the back plate there should be 8 jacks
more than needles in the front plate. Now starting at the right, count
eight jacks, which leave in operating position; then draw five back out
of operating position; leave eleven in operation, and drawn five out.
Alternate in this way with eleven in work and five out for the length of
the work.
[Illustration: Fig. 64. Basket Weave Design Made on Purl Stitch Hand
Machine.]
After doing this the position of the jacks would be similar to those
shown in the back plate in Fig. 60, except that that illustration showed
three in and three out, while we would have eleven in work and five out
in the present instance. The three rules marked _m_, shown in Fig. 60,
are used for this purpose. They save the time of counting the jacks and
drawing them back one or two at a time. By the use of one of these
rules, properly cut, all of the jacks to be put out of operation may be
moved back in one sweep.
To go back to our design, set the pin shown in the arc _e_, Fig. 60, to
stop the racking handle at eight needles, put on six courses or three
rounds, stopping with the carriage on the left, which will leave all the
needles in the front plate, and rack the back plate to eight needles to
the left. Put on three more rounds and rack the eight needles to the
right, and continue doing this.
It should be understood that the back plate should never be racked over
more than two needles except when all the needles are in the front
plate. I have previously explained that when the cams are set for purl
stitch, if the jacks are in the operating position in both plates we
would make the purl stitch, but in any place where the jacks were drawn
back out of operating position in one plate, in that place the needles
would at all times stay in the opposite plate and knit the plain jersey
stitch.
Now in this basket design we have in the back plate, disregarding the
first eight jacks, five jacks that are not operating alternating with
eleven that are. Therefore, the first three rounds would make purl
stitch on eleven needles alternating with five making plain jersey
stitch.
When we rack the plate over eight needles we find that the five slots
with the non-working jacks of the back plate are just opposite the
middle five needles of the eleven that have been making purl stitch, and
are, of course, at the time of racking in the front plate. We also find
that the five needles that have been making the jersey stitch in
consequence of having been opposite the five non-working jacks in the
back plate, are now opposite the middle five of the eleven working jacks
of the back plate. Therefore it is plain that these five needles would
make purl stitch for the next three rounds, while the middle five
needles of the eleven that were making purl stitch would make jersey in
the next three rounds. There are always three needles on each side of
the five that are racked over that purl stitch all the time.
Two and Two Rib
Fig. 65 shows two designs the lower one being very simple. With the
carriage on the left end of the machine arrange the jacks in the back
plate two and two, or two in working position and two out. Then move the
carriage across to the right end of the machine and we will find that
the needles have arranged themselves to conform to the arrangement of
the back jacks, alternating two and two in both needle plates. Now move
the handle _b_, Fig. 61, to the left and this will raise cams _a_ and
_b_, Fig. 62, up into the cam plate out of operation, thus preventing
the jacks from moving to their innermost position. Therefore, they
cannot exchange needles and so would make a two and two rib fabric,
knitting this continuously without any further change.
[Illustration: Fig. 65. Diagonal Diamond Design and Two and Two Rib Made
on Hand Purl Stitch Machine.]
The upper half of Fig. 65 is made by arranging the jacks in the back
needle plate so that five will be in working position, alternating with
five out. With this arrangement of the jacks, and without any further
manipulation, the machine would knit a straight vertical stripe of five
needles purl stitch and five needles plain jersey stitch. If, however,
we rack the back needle over one needle every round when the carriage is
at the left end of the machine, and all the needles are in the front
plate, for five rounds we would have these stripes running diagonally
instead of vertically, and the distance they would run to the right or
left, depending on which way we racked, would depend on how many times
we racked in one direction. In this instance it would be for seven
rounds, or rather we would rack over in the one direction every round
for six rounds, and on the seventh we would rack the plate back the five
needles at once. Then start over racking the other way one needle each
round as before to make the second row of diagonal blocks. This racking
back of five needles at one time would of course bring the non-working
jacks to the position where the working jacks were, and the working
jacks to the position where the non-working jacks were. Therefore, the
needles that were knitting the purl stitch would begin making plain
jersey, while the needles that were making plain jersey would now make
purl stitch.
[Illustration: Fig. 66. Two and Two Rib Racked, Made on Purl Stitch
Machine.]
Fig. 66 is simply a two and two rib stitch racked over two needles every
four rounds. This racking over two needles with needles in both plates
may be done successfully if the stitch is drawn fairly long.
Automatic Jacquard Power Purl Stitch Machine
The automatic links and links or purl stitch machine is what the name
would imply; that is, a machine which makes the changes in the stitch
and yarn carriers automatically. The word jacquard added to this would
convey to the mind of a person familiar with textile processes the fact
that the machine automatically makes designs or patterns in the process
of knitting.
Fig. 67 shows a Dubied machine of this type which in general appearance
resembles their automatic power flat machine. It has the same drum
device for counting the rounds, indicated at _d_, with a chain drive
somewhat similar to the flat machine, though with this difference: The
carriage is connected directly to the chain through a cross head which
slides on two rods, instead of through a connection rod. We have the
main chain, at _e_, on this machine as on the flat machine, but it is
placed on the right end instead of the left. The racking chains which
are on the flat machine are not needed on this machine, therefore are
dispensed with.
[Illustration: Fig. 67. Dubied Power Automatic Jacquard Purl Stitch or
Links and Links Machine.]
[Illustration: Fig. 68. Cross Section of Pair Purl Stitch Machine Plates
With Card Cylinder and Their Relative Positions.]
On the ordinary purl stitch machine a large part of the designing is
done by a combination of selected jacks in conjunction with the rack;
therefore it is desirable to have such a machine built to rack over
quite a number of needles. With this machine the designs are made on the
jacquard system, therefore this extreme racking is not required and the
machine is built to rack but two needles. At _a_ and _b_ in Fig. 67 will
be noted two cylinders with grooves cut on a long spiral. They are
mounted on a small shaft which acts as a bearing upon which they turn.
These operate the jacquard system and should be kept well in mind as
they will be referred to later. The letter _c_ indicates the carriage,
which is shown, top and bottom, in detail in Figs. 69 and 70.
Fig. 69, it will be noted, is the same in the general layout of the cam
system as shown for the hand machines in Fig. 62, in the last article.
The upper locks would operate on the front plate and the lower ones on
the back one. There are two main points of difference: The cam _x_,
which must be used in connection with the cards of the jacquard system
and which will be taken up in detail in due course, and the levers _s_
and _t_ which raise the stitch cams that are in the lead and lower the
ones that follow and form the stitch at the end of each course. This is
done to take all undue strain off the stitch.
It will be noted in the illustration that the left stitch cams are
raised and the right ones lowered preparatory to putting on a course by
moving the carriage from right to left. At the left end of the machine
the position of these cams is reversed for the return course. This is
done by a pin set at both ends of the two plates which act on the levers
_s_ and _t_. Then we have the extensions of the slides. Numbers 1 and 3
are for changing the length of the stitch. Slides 2 and 5 are for
raising and lowering cams _a_ and _b_ to change from purl to plain
jersey stitch, or vice versa. The manner of doing this and the action of
these cams on the needles and jacks have been explained.
Slide 4 puts the plunger _y_ into and out of operation. This plunger
operates the jacquard system by entering the spiral grooves of and
turning the cylinders _a_ and _b_, Fig. 67. The four slides marked 6,
Figs. 69 and 70, are for changing the yarn carriers, of which there are
four. The four small parts indicated by the letter _m_, Fig. 69, are
latch openers, which are essential as the machine cannot be operated
when the latches are closed. We would be unable to move the carriage
across the machine when there was no fabric on the needles to open the
latches, without these latch openers.
[Illustration: Fig. 69. Under Side of Carriage of Automatic Jacquard
Purl Stitch Machine.]
The small slide indicated at 7 is for changing the position of the cam
_x_, swinging on a pivot screw at _z_, which may be moved to any one of
three positions. These are the position shown, or horizontal with the
lower edge of, and on a line with the lower edge of cams _w_ and _r_, or
it may be swung down to a point where the end will be at the lower edge
of the cam plate at _v_. The three positions of this cam should be
firmly fixed in mind, as they have an important part to play in the
jacquard work.
[Illustration: Fig. 70. Top Side of Carriage of Automatic Jacquard Purl
Stitch Machine.]
We will now give our attention to Fig. 68, which represents a cross
section of the needle plates, showing a pair of jacks and a needle in
their respective slots or tricks. Letter _a_ indicates the back plate
and _b_ the front one. The back jack _c_ is shown in its outermost
position, therefore would be out of operation, while the dotted lines at
_h_ show its innermost position ready to receive the needle from the
opposite jack. Letters _e_ and _f_ indicate the gibs which cover and
hold down the heads of the jacks at all times except when they are at
their innermost position; when they are in this position they are under
and held down by the bridges or winkles _c_ and _d_, Fig. 69, and are
permitted to rise only at the concaves _e_ and _f_ where the exchange of
needles takes place. Letter _g_, Fig. 68, indicates the needle, and _i_
is a vertical projection, called teeth, which are between the needles
and act as sinkers for the needles to draw the loops over.
The Jacquard Mechanism
The jacquard system of designing is simply a method of providing means
to select and put into operation any desired needle or needles at any
predetermined place in the fabric. The mechanism to do this is shown in
Fig. 68. The letter _l_ indicates a four cornered star shaped bar called
the card cylinder, which is the length of the needle plate. The letter
_j_ indicates what are called cards and are also the same length as the
needle plate and as wide as one side of the card cylinder. These are
made from either thin sheets of steel or from stiff strong paper board,
and are attached to one another by rings or other means so as to form a
continuous band around the card cylinder. The illustration shows ten of
these cards, but the number used depends on the design being made, for
there is one card for each round in the design.
To return to the card cylinder _l_, this is mounted on a shaft which is
supported by two uprights or arms, one at each end, shown by the broken
lines at _n_, which in turn are attached securely to the rocker shaft
_m_. This arrangement permits the card cylinder to be swung forward to
the needle plate and back to the position shown at any predetermined
time or place. As noted before, the back jack _c_ is out of working
position, therefore as long as it stays in this position the needle
would operate in the front plate only and make a plain jersey fabric.
If, when the carriage is at the left end of the machine, we should swing
the card cylinder with the blank card _j_, No. 1 (which is a card
without any openings in it) up to the needle plate, it would push these
back jacks up into working position and on the next course the needles
would cross over into the back plate and make the purl stitch. Now bear
in mind that the basic principle of designing of this character is in
making the design of one stitch and the ground of the other. It is quite
obvious that if we provide means to sweep all the back jacks to their
outermost positions and out of operation every time the carriage is
moved from the right to the left end of the machine after having passed
the needles across to the front plate, then swing a card with holes cut
through at certain intervals up to the needle plate, those jacks that
come into contact with that part of the card that is intact would be
pushed into working position, while those that were in front of the
openings or holes would pass through and not be affected. Therefore, on
the next round the needles opposite these would make the jersey stitch,
while all the others would make purl stitch. On the last course of the
round from right to left the jacks would be swept back out of operation,
the card cylinder _l_ would be turned a quarter turn, bringing another
card opposite the needle plate, and another and perhaps different lot of
jacks selected for the next round.
The card cylinder is turned the quarter turn when the carriage is
approaching the right end of the machine by the plunger _y_, Fig. 70,
engaging the spiral in the cylinder _b_, Fig. 67, and the cards are
moved up to the needle plate when the carriage approaches the left end
of the machine by this same plunger engaging the spiral in cylinder _a_.
At _k_ in Fig. 68, is shown the face of a portion of a card as it might
be cut. Beginning at the opening at the left, the heels of three jacks
would pass through this. The space next to the right, being intact,
would push six jacks into operation; and so on throughout the length of
the fragment of the card shown as indicated by the figures. This drawing
was made to represent a card to be used on a needle plate cut eight
needles to one inch, and while the scale is cut down somewhat in the
reproduction the proportions would remain the same.
Now as to the means provided to make the changes shown as necessary we
will refer again to Fig. 69, and to the cam marked _x_. As stated
before, this cam may be swung on the pivot screw _z_, automatically, to
any one of three positions. When it is in alignment with cams _w_ and
_r_ it has no effect, as when the jacks are in their normal knitting
position the butts will pass just above and when they are out of working
position they will pass just under these three cams. Now it will be
noted that cam _x_ is placed at the extreme right end of this lock or
set of cams, in consequence of which it must always be put into
operation when the carriage is at the right end of the machine, and it
performs its functions as the carriage is moved to the left and after
the stitch formation of this course is completed.
The cam is moved into the desired position by the slide 7, which comes
in contact with movable stops at either end of the machine. When the
jacquard system is in operation this cam would be moved to the position
shown in the illustration while the carriage was on the right,
consequently as the carriage is moved to the left end of the machine the
needles in the back plate would be passed to the front plate and
immediately after this the back jacks would be swept out of the
operating position by this cam.
When the carriage reached the left end of the machine this cam would be
moved down in alignment with cams _w_ and _r_, so would be in the
position that would not make any change in the position of the jacks.
In making some kinds of work it is desirable to put all the back jacks
in and out of operation at certain times. We have just explained about
putting them out of operation. To put all of them in the working
position without using the jacquard the before mentioned movable stop
comes in contact with another slide just under slide 7, when the
carriage is moved to the right end of the machine, and this slide will
swing the point of cam _x_ to its lowest position at _v_, and in this
position, as the carriage is moved to the left, it will sweep all the
back jacks into working position ready for the next course. As the
carriage finishes its travel to the left, the stop at that end would of
course move this cam to its neutral point.
I assume that the reader understands that the stops and levers that
cause all these automatic changes are controlled by studs attached in
their proper places on the chain _e_, Fig. 67, which in turn is
controlled by the drum _d_.
We will now take up in more detail the action of the cards and the
mechanism provided to actuate them. As stated before, when making a
design by this system the card cylinder, together with the cards, is
moved up to the edge of the needle plate each round. Referring to Fig.
67, at _a_-1 there is an eccentric attached to the movable cylinder _a_,
and there is a connection rod from this eccentric to the small shaft
_o_, Fig. 68. Therefore, when the plunger _y_, Fig. 70, enters the
spiral groove and moves the length of the cylinder _a_, Fig. 67, the
cylinder turns about half way round, which of course turns the eccentric
_a_-1, and this moves the card _j_, No. 1, Fig. 68, up to the needle
plate. As noted before, any part of this card that has holes in it could
not push those, jacks opposite into working position, while that part of
the card which remained intact would put the jacks opposed to it in
work. Upon the return of the carriage it turns the cylinder _a_, Fig.
67, back to its first position, which movement would of course move the
cards away from the needle plate again. The cylinder _b_ is actuated in
the same manner as cylinder _a_ as the carriage reaches the right end of
the machine, but its function is to turn the card cylinder a quarter
turn each time in order to bring a new card into position for the next
round and make that part of the design.
How Designing Is Done
Having explained the theory of making designs on the jacquard system we
will now show in detail how it is done in actual practice. With the
jacquard system there is no limit or end to the designs that may be
made, as there is with the other systems used on knitting machines.
Fig. 71 is a photographic reproduction of a design made on this machine.
The reader who has studied well and thoroughly digested what has gone
before will realize that this design could not be made in any other way,
on a machine of this type, without an expenditure of time and labor
which would be far beyond the bounds of practicability.
The designer will first sketch out his design on a piece of plain paper,
then take a piece of cross section paper and lay it down as illustrated
in Fig. 72. This is the layout of the design shown in Fig. 71. Each of
the crosswise rows of squares represents one round or two courses, and
each of the vertical rows represents a wale or needle. In other words
each one of the squares in a crosswise row represents a needle or the
loops in one round, and each one of the succeeding squares represents
that same needle in the succeeding rounds.
[Illustration: Fig. 71. Design Made on Automatic Jacquard Purl Stitch
Machine.]
[Illustration: Fig. 72. Layout of Design Shown in Fig. 71.]
Now to cut the cards we would start with No. 1 and cut them
consecutively. Referring to Fig. 72, the blank squares, or the spaces in
the cards these represent, should be cut out, and the squares marked
with an _x_ would remain intact. Starting at the right side, one needle
space is not cut out; then sufficient space to cover three needles or
jacks is cut out; then the space of eleven jacks is left intact, then
three cut out. This is the full width of the first round of the design,
therefore this cutting would be repeated until it covers the desired
width of fabric. Card No. 2 would be cut as follows: One space cut, one
left intact, three cut out, nine left intact, three cut out, and one
left intact. This should be repeated as with No. 1 card. Each card
thereafter should be cut according to the marking of the cross section
paper, and numbered as cut, so as to avoid trouble in assembling them in
their proper order when finished.
It should be understood that the part of this layout from the right side
to the dotted line is the complete design, and all to the left as well
as above and below, would be a duplicate of this.
After these cards are put on the card cylinder, attached like an endless
belt, and the machine is in operation, when card No. 18 has finished the
last part of the design, card No. 1 will start immediately in the next
round on its part of the design. When it comes to card No. 6, that
square will have been completed, and a new square in the center section
will have been started.
The two-tone color effect is made by using two different colored yarns
and using a plating yarn carrier. This throws one color on the face in
the jersey stitch and the other color on the face in the purl stitch.
[Illustration: Fig. 73. Claes and Flentje Automatic Narrowing Machine.]
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