Note: Descriptions are shown in the official language in which they were submitted.
``` 1047782
Specification
_ _
T~is invention relates to a method of warp knitting
and to a warp knit fabric produced therebyO
In the apparel lndustry, garments ex~ibiting both
hlgh moisture regain and high ~tretch are in great demand.
For instance, undergarment6 and leieure garments (such
as golf and tennis outfits) must provide the wearer with
suitable ela~ticlty 80 that the wsarer' 9 mobility will
not be unduly hampered. At the same time, however, the
garment must be hlghly absorbent 80 that the wearer will
not feel discomfort due to unabsorbed perspiration.
Heretofore, fabric producers have not been able to
inexpensively produce absorbent stretch fabrics. Woven
fabrics have alway~ been limited because of their slow
production rates. Also, the inherent elasticity of a
woven fabric cannot compare with that of knit goods. Weft knit
fabrics sometimes lack the dimensional stability needed
to withstand repeated launderings, and they are still not
as inexpenslve to produce as warp knit fabrics.
Accordingly, lt is an ob~ect of the present invention
to provide an ab~orbent ~tretch fabric and a method for
producing such fabricO
It is a apecific ob~ect to provlde such a method
that i8 characterized by relatlvely high production rates,
thus provlding a fairly inexpensive fabric.
Further, lt is an ob~ect to produce an improved
ab~orbent stretch fabric that provides great com~ort and
elasticity to the weaver.
- 2
'';`;-
. ..: .
104778Z
These and other obJects are met by the novel
method and fabric disclosed herein. Basically, the
method can be used in con~unction wlth any conventional
warp knlt machine as lo~g as the knittlng machine is
provlded wlth more than one yarn gulde barO The guide
bar olosest to the knittlng needles is threaded with
a stretch-type yarn. One of the other guide bars iB
then threaded wlth a yarn exhibltlng hlgh molature
regaln properties. During knltting, loops of the absorbent
yarn extend toward a first fabric side, while the
loops formed from the stretch yarn extend toward the
second side. Diagonally extending laps of absorbent yarn
are formed on the second fabric slde, whlle dlagonally
extending laps o~ the stretch yarn run along the first
fabric side.
Preferably, the fabric i9 produced on a two bar
warp knit machine.
The inventlon will be further understood by reference
to the accompanying drawings and detailed descrlptlon
of the preferred embodlments. In the drawings:
Figure l ls a stitch loop diagram on an enlarged
scale of one embodlment of the novel warp knit construction;
Fi~ure 2(A) 18 a polnt dlagram, lndlcating the
lapping movements of the guide bars needed to produce
the ~abric shown ln Figure l;
Fl~ure 2(B) is a polnt diagram of another embodi-
ment o~ the invention;
Flgure 3 is a perspective view showing the relation
between the gulde bars, guides, needles, and needle bar,
and also depicting the manner ln which the guides are
threaded;
~ 3 --
`- :1047782
Figure 4(A) i9 a perspective view of a knitting
needle with part of the needle cut away 90 as to show
the yarn lapped therearound;
Figure 4(B) 18 a cutaway top vlew of a needle wlth
yarns-lapped therearound, the entire beard portion of
the needle cut away for simpliflcation.
Wlth reference to the drawing~ and especially to
Figure 3, there 18 shown the knittln~ area of a conven-
tional two guide bar warp knitting machine. The inventlon
can be fully practiced on any standard warp knit machine
having at least two guide bars. For example, the Reading
BL~2 tricot machine, manufactured by the Textile
Machlnery Dlvi~lon o~ North American Rockwell Corp.,
Reading, PennsylYania, wlll pro~ide optional results.
Guide bar~ 2, 4, have vertically mounted elongated
6uides 2(a), 4(a), re~pecti~ely, depending therefrom.
The ends of the guides are provided with eyes, ao that
yarn ¢an be threaded therethrou~hO -
As ls ¢on~entional in the art, euide bar 2 will
be ~ub~equently referred to as the front bar, and guide
bar 4 wlll be subsequently referred to as the back bar.
As can be seen ln Figure ~, the back bar 18 closer to
the needle6 than is the front bar~
Xnltting needles 6 are reciprocally mounted ln
needle bar 8 80 that they may be raciprocated vertically
(upwardly and downwardly) during the knitting cycle
in a manner well known in the artO
The normal knitting cycle and other warp knitting
concepts such as point diagrams and chain arrangement~
for the guide bars, are explained in detail in "Warp
Knitting Technology", by D.F. Paling, Columbine Press,
second edition, reprinted 19700
- 4 -
. - . -. ~ .
1047782
Basically, a knltted loop 19 formed when yarn
lapped about the bearded portion of the needle moves
upwardly over yarn captured withln the needle beard.
This motlon is commonly referred to as "knock-over".
As 19 conventional ln the warp knltting art, the guide
bars may swlng backwardly (to backslde 3 of needle
bar 9) and forwardly (to frontslde lO of neelde bar 9).
Also the gulde bars can be moved in an endwise or lateral
manner (parallel to the nzedle~). Lateral movemsnt of
a guide bar in front of the needles is referred to as
underlap, whereas lateral movement of the guide bar~
behind the needles (on the beard side) is referred to
as overlap. The lateral movement of the guide bars
controls the knltted stltch pattern. Ina~much as all
of the guides on any one guide bar move as a unit, the
lateral movements of any single guide can be recordsd
as the stltch pattern. Pattern wheels or chain l~nks
cause the guide bar to traverse the desired number of
needle6. me pattern wheel or chaln link engages a
pattern whe~l roller or chain link follow~r that are
connscted to a gulde lever or gulde rocker arm, thu~
transmlttlng rotation of the pattern wheel or chaln to the
de~ired lateral movement of the guide bar a~ 18 well
known ln the warp knltting art.
As can be ~esn in Flgure 3, stretch~type yarn Ll
18 tled lnto the back guide bar, and absorbent yarn L2
i~ tied lnto the front bar. As the yarns are placed
around the needles after overlapping, lt will be apparent
that yarn Ll will more closely implnge the needle shaft
than doe~ yarn L2.
-- 5 --
- ~ .
- 104778Z
It will be apparent that slnce aach guide i8 threaded,
each needle will be provlded with two yarns after the
overlapping movements of the guide bars. Thus, due to
the novel ~ethod of tying an absorbent yarn into the
front bar and tying a stretch yarn into the back bar,
a fabric will be produced where loops composed of the
- absorbent yarn wlll extend toward a first fabric side,
while loops of the stretch yarn will extend toward the
second fabrlc side.
Figure 4(A) illustrates the manner in which the
yarns are lapped about the needle. In this Figure, part
of the needle beard has been cut away. It can be seen
that if the yarns are captured in the needle beard,
yarns passing along the needle shaft that slide over
the bear will form knitted loops. ~gain, see the Paling
textbook for a full explanation of the conventional
knitting cycle.
Figure 4(B) is a top cutaway view illustrating the
fact that stretch-type yarn ~ more closely impinges
the needle shaft than does absorbent yarn L2.
Figure 2(A) i8 a point diaEram illustrative of the
lapping paterns of the front and back gulde bar that
are necessary to produce the fabric shown in Figure 1.
To produce the lapplng movements shown in Figure 2(A),
the chain or pattern whael controlling the ~uide bar must
con3i~t of links or steps arranged in a certain manner
so as to properly engage the guide bar push-rod or lever.
The chaln arrangement for the front bar iB determined
by viewlng the dotted line, while the solid line represents
~0 the back bar, Thus, the chain arrangement of the front bar
is 1-0/1-2, and repeat. The chain arrangement for the
back bar 18 1-2/l~0, and repeat~
- 6 -
A
~C)47782
Flgure 2(B) shows another point diagram illustrating
yet another guide bar lapplng pattern that wlll produce
an lmproved ab~orbent ~tretch fabric. The chain arrange-
ment of the front bar again is determined by viewing the
dotted line, and the back bar arrangement i~ determined
by viewing the solid line. Here the chain arrangement
of the front bar is 1-0/1~2, and repeat. The chaln
arrangement of the back bar is 2-3/1-0, and repeat.
Figure 1 i8 an enlarged stitch loop diagram of the
fabric produced when: absorbent yarn L2 i8 threaded
into the front ~uide bar, stretch yarn ~ i8 threaded
into the back guide bar, and the chain arrangements
shown in Figure 2(A) are used. It is apparent that loops
12 of absorbent yarn L2 axtend toward a first fabrlc side,
while loop~ 14 of stretch yarn ~ extend toward the æecond
f~abr~c side. Note also that the lapping motion produces
diagonally extending laps that run from wale to wale.
Lap~ 16 of absorbent yarn L2 run along the second fabric
side. In combination, the loops and laps of absorbent
yarn substantially envelop the stretch yarn ln the fabric.
Laps 18 of stretch yarn ~ run along the ~irst fabric
side.
I have found that when yarns spun on the woolen,
worsted, or cotton systems are used a~ absorbent yarns
in accordance with the invention, enhanced results are
created~ For instance, cotton, wool, and hi~h wet modulus
rayon yarns ha~e been optimally knitted with ~tretch
yarns to form stretchable yet hlghly comfortable absorbent
fabricsO
~0 ~uitable 8tretch yarns to be e~ployed may include
~ynthetlc yarna formed from polyesters, polyamides,
acryllcs, etcetera.
~ 7 ~
' ~
~4778Z
Also, the corespun type of elastomerlc yarn, characterlzed
by havlng an elastomerlc filament core surrounded by
staple fibers that have been twlsted about the fllament's
axls, can also be advantageously employed as stretch yarn8 - -
ln accordan¢e with the lnventlon.
It wlll become apparent that a myrlad of possible
combinatlons of yarn selectlon and lapping sequences can
be employed in practicing the inventlon, all falling within
the scope and spirit of the appended claims.
~ 8
,~y'`'
