IMPROVEMENTS IN LOOMS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by William Wilson Melville at the Office
of the Commissioners of Patents on the 20th October 1883.
WILLIAM WILSON MELVILLE, of Roebank, Beith, in the County of Ayr, Silk
Printer, "IMPROVEMENTS IN LOOMS,"
"
This Invention relates to improvements in looms for weaving two or more webs
of cloth simultaneously, the object being to render practicable the working of this.
class of looms, and to apply them in weaving various fabrics for which they have
not hitherto been adapted.
In carrying out the Invention, two or more separate horizontal lines of warp are
led, as usual, from the warp beam to a breast beam or beams in the front part of
the loom. The reed through which the warp passes is of extra depth and is
divided by horizontal bars which separate the lines of warp and form the races for
the shuttles which are used to carry the weft for each web. Instead of employing
the usual mails and connecting together two or more mails to act on the corre-
sponding threads of each line of warp, long mails of special form are used and are
attached to single jacquard harness and weighted. The mails are formed by long
thin strips of brass, copper, steel, or of glass or other suitable material, with two or
more eyes in them, through which the warp threads pass, the eyes being formed at
distances apart corresponding to the vertical space between the lines of warp. The
object of using the form of mails described is to enable a perfect shed to be formed
in each line of warp by the action of the jacquard apparatus, an object which is not
attainable, at least in weaving fine fabrics, by the use of separate mails for each
line of warp, owing to the knots of the threads by which the mails are tied coming
into contact with and partially raising or lowering occasional warp threads in the
adjacent line of warp. Instead of using long mails, loops or eyes may be formed at
the requisite distance apart in the ends of the jacquard harness. The loops or eyes
are formed by using a double thread and twining one round the other at the top
and bottom of each eye without forming knots, a long loop being left at the
extreme lower end to which the leads or weights are attached.
When leaves of heddles are employed to form the shed in the several lines of
warp, the beddles are fitted with long mails of the form above described, so that
they somewhat resemble deep reeds. The warp threads which pass through the
eyes of the long mails in one leaf of the heddles, pass between the mails in the
adjacent leaf, and a perfect shed is readily formed.

page_text: In weaving fine fabrics in a hand loom, the weaver will in general be able to
detect broken warp or weft in two or more webs, but in weaving heavier fabrics
more especially in power looms when the lower web or webs may not be easily
observed, it is preferred to employ an arrangement of stop motion in connection
with the lower lines of warp whereby the loom may be stopped on the breaking or
failing of any warp thread. For this purpose, light droppers or detectors, such as
doubled wires, are hung on the warp threads of the lower webs at a sufficient
distance from the heddles or harness to be unacted on by the shedding of the warp.
These droppers pass through a slotted bar, which serves to retain them in position,
and when any warp thread breaks or fails, the corresponding dropper, being no
longer suspended by the thread, falls through the slot or guide on to a rotating
ribbed roller or similar device whose motion is thereby stopped, and which is
caused to act on the belt or on the operating mechanism of the loom to throw it
out of action. For the upper line of warp, such a stop motion is not required, as
broken threads can readily be detected, but the arrangement described may be
applied with advantage to the lower line of warp, or to each of the lower lines
when there are more than two. Weft forks may also be fitted to each division of
the reed to stop the loom when a weft thread of any of the webs breaks or fails.
Instead of, or in addition to, applying a stop motion arrangement in connection
with the lower warp, mirrors or other reflecting surfaces may be fitted below or at
each side of the webs and in front of the harness; and such surfaces may be so
inclined or angled that the lower web, or both the upper and lower webs, or the
lines of warp may be reflected by them and be seen by the weaver. Broken
threads or imperfect weaving may thus be detected during the progress of the
weaving.
It will in general be advantageous to weave the separate webs of cloth of the
same pattern, but different patterns may be produced by connecting each line of
warp to separate shedding harness fitted with long mails having single eyes. The
shuttle boxes for each line of warp may also be operated by separate "motions," &
convenient arrangement, when several shuttles are used for each web, being to fit
the shuttle-boxes so that they slide and shift horizontally and longitudinally at
each end of the lathe.
The various arrangements herein described may also be employed in weaving a
number of narrow widths simultaneously from each line of warp. In weaving such
fabrics as handkerchiefs for example, each web may be woven with a double row
of gauze, at intervals or at the centre to form a partial selvedge, so that the webs
may be divided longitudinally into pieces of the desired breadth. The lines of
gauze weaving are conveniently formed in using the improved mails, by passing
the warp threads, which effect the twisting or twining action of gauze weaving,
through "doups" passed through the eyes of the long mails and acted on by the
jacquard harness. Or a short comb or reed for each line of warp, fitted imme-
diately behind the main reed and having the requisite lateral reciprocating motion
imparted to it, may be employed to produce the lines of gauze weaving. By
employing suitable combs or reeds, or "doups" of the kind referred to, in
connection with each line of warp, gauze weaving may be produced throughout
or entirely across the fabrics. Or by applying such arrangements to one line of
warp only, a gauze or leno fabric and a plain fabric may be woven simultaneously.
Narrow fabric, such as tapes or ribbons, may be woven in lines over each other,
by fitting in connection with each reed or horizontal division of the reed, the usual
shuttles or spools employed to form the selvedges of the fabrics. In weaving such
narrow fabrics in looms in which two or more lines of warp are carried horizontally
over each other, the warps of each piece of the fabric may be so spaced, that the
pieces of the lower line or lines may be woven below the spaces left between the
upper pieces for forming the selvedges. The harness mails in this case may have
Bingle eyes when the loom is arranged to weave two lines of warp, and two eyes
when four lines of. warp are used, as the harness may be arranged entirely across
the loom, and while one portion will manipulate the warp of the upper pieces or

page_text: lengths of fabric the adjacent or alternate portion will be used for the lower pieces.
A separate set of spools or shuttles may be used for each line of warp, but may be
carried by the same reciprocating frame
When the selvedges are formed or partly formed by the action of the harness,
the requisite harness ends are interposed between or arranged in front of the
alternate portions of the harness which are used to manipulate the upper and
lower lines of warp.
Seamless bags and other tubular or two-ply fabrics may also be produced by
employing two sets or plies of warp thread in each line of warp, and providing the
shedding harness or journals with the long mails herein described.