A NEW OR IMPROVED SHEDDING MECHANISM FOR LOOMS
Year: 1876

page_text: LETTERS PATENT to William McIlwraith, of Glasgow, in the County of
Lanark, North Britain, for the Invention of "A NEW OR IMPROVED
SHEDDING MECHANISM FOR LOOMS."
PROVISIONAL SPECIFICATION left by the said William McIlwraith at the
Office of the Commissioners of Patents on the 10th November 1876.
WILLIAM MILWRAITH, of Glasgow, in the County of Lanark, North Britain.
"A NEW OR IMPROVED SHEDDING MECHANISM FOR LOOMS."
This Invention has reference to a new or improved construction or general
arrangement of mechanism susceptible of considerable or various modifications for
primarily producing the shedding action or motion of the warp in power or other
weaving looms in accordance with the desired pattern, preferably made portable
like most of the other or ordinary jacquard or dobbie mechanisms, and controlled
by any of the usual pattern barrels or cylinders and sets of cards or chains used in
these, and connected to heddles or other harness above and below direct or through
the ordinary jack or other arrangement of levers or cards and pulleys as to produce
the shed of the warp threads in a positive manner both up and down, and back to
their normal or even position in the same plane, thus giving a more regular and
certain action to the heddles or harness than by springs or weights with less strain
and wearing friction on these and the weft than has been heretofore obtained, and
particularly suitable for the better weaving of muslins and other fine fabrics at
higher speeds in power looms than heretofore.
And the essential nature and novelty of the Invention consist in ranging as
many short thin metal bars (say from six to twelve inches long, and from half an
inch to one inch thick) as there are levers or heddles or rows of harness to be
moved or shed as close together edgeways as convenient in slotted guides, in or on
two reciprocating cross or drawing bars, near their ends, so as to guide or recipro-
cate any number of the draw rods to and from each other to form the shed, or
place them all in their normal plane ready for making another change and shed;
all by the positive motion of the cross drawing bars, actuated by antifriction
pulleys on their ends projecting into double grooved cams outside of and through
[Price 6d1

page_text: their slide guides formed in two side frames secured together by cross stays to
carry the whole mechanism, when that is made portable as preferred. These cams
are secured close to the side frames on the opposite ends of a light shaft revolving
in stationary bushes in the centre of the frame between the reciprocating cross bars
(corresponding to that of the drawing knives or "branders" of other dobbies),
which have a row of lateral holes formed through them fitted with locking bolts, one
opposite each draw rod, formed with a check or notch at each end opposite these
bolts when the draw rods or bars are at their extreme furthest position from each
other, and throw off their cams, so that the bolts can enter the checks in this
position by the action of the shifting or pattern needles (and ordinary controlling
cylinders and cards or other pattern mechanism), and so lock each of the draw rods
to either their upper or lower drawing cross bars, as will herein-after be more
particularly described.
The cam shaft is driven by toothed wheels from one of the loom shafts at half
the speed of its crank shaft, as the cams are double and make two in or out move-
ments of the cross drawing bars and their locked draw rods, equivalent to two sheds
of the warp, which is moved by two sets of parallelly connected and acting beam
levers or segmental pulleys mounted on a fixed spindle for each set at the top and
bottom of the side frames, and corresponding in number to that of the levers of
the warp threads and the draw rods or bars, and over and under these, so that the
upper and lower ends of each are connected by a wire or link to the inner or shorter
arm of each corresponding lever of the upper and lower set of levers, which have
their outer or longer arms connected by wires or links, which are so connected to
the levers of the heddles or warp or their levers as to give them their full shed of
from three to five inches, as desired, through the proportional lengths of the con-
necting or primary levers to that of the throw of the cams and drawing cross bars,
and which is preferred to be about an inch or inch and quarter on each, giving the
combined motion inwards of two inches or two inches and a half on the drawing
rods and inner ends of the primary lever to produce the shed, their outward position
corresponding to the level or even position of the warp.
The said locking of the cross moving bars to the draw rods sliding through them
is effected by the outer ends of the locking bolts, which have each an eye or other
equivalent, sliding freely on the new stem of their moving or locking and unlocking
needles during their motion in and out with the cross bars, and. so as to be moved
by one (preferably the upper) set of needles direct, which both work in stationary
guides fixed nearly in a line with the locking bolts when in their said outer
changing and locking position, where they are moved by the forward motion of the
ordinary cylinder of the pattern mechanism carried opposite the upper set of needles
in the free ends or arms of the rocking levers or frame carried on one side of the
frames and actuated preferably by an improved cam on the shaft of the other cams,
and which by two outer cam or segmental surfaces at the extreme inner throw of
the cylinder holds it there for a short time after it has forced in the needles of the
upper set to be locked against the power of the usual light spiral springs or other
equivalent on the needles, in this case preferably on the lower set, which in this
free changing position of the bolts lock the lower set all inwards and through a set
of light oscillating levers, each with its opposite end passing through an eye in the
back end of each upper and lower needle, and brings the ends of the upper pattern
needles all out to this their normal position, so as to have those of the upper set of
bolts to be locked to the draw rods and upper cross bar pressed in by the pattern
cards and held there, as stated, until the cams have moved both cross bars some
distance inwards, sufficient to free a light spring locking blade mounted on the
upper cross bar, so that it enters on one or other of the sides of short pins or
projections on one side of the upper lockers or other equivalent to hold them all
locked into the draw rods and cross drawing bars, they were set to and determined
by the pattern cards or barrel, and hold them thus while forming the shed and
bring the weft and drawing cross bars back to their pattern changing position, the
last part of which motion brings the spring locker of the bolts up against releasing

page_text: stops, so that the bolts and their moving needles are set free ready for the next
change and fresh shed, and so on successively.
This mechanism may be arranged to work at any angle and position desired to
suit the loom or its shedding heddles or harness or the actuating levers of these,
and when made portable it can be removed and another attached in a few minutes
when anything goes wrong with it or its pattern gear, with little stoppage of of the
loom.
This improved shedding mechanism is also very suitable for working the single
primary lever, and connecting the usual loose harness thereto for producing the
twisting or crossing of the warp sheds used in gauze or leno fabrics for the more
efficient binding of the work. The cross draw are reciprocated to and from each
other in slotted guides in the two side frames on each side of the cam shaft, and
directly opposite each other.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William McIlwraith in the Great Seal Patent Office on the 7th
May 1877.
WILLIAM M ILWRAITH, of Glasgow, in the County of Lanark, North Britain.
"A NEW OR IMPROVED SHEDDING MECHANISM FOR LOOMS."
My said Invention has reference to a new or improved construction or general
arrangement of mechanism susceptible of considerable or various modifications for
primarily producing the shedding action or motion of the warp in power or other
weaving looms in accordance with the desired pattern, determined by the pattern
cards, barrel, or other pattern mechanism, and preferably made portable, like most
other ordinary shedding jacquard or "dobbie" machines or mechanism, and con-
trolled by any of the usual pattern barrels, cylinders, or sets of cards or chains
used in connection with these machines, and connected to the ordinary heddle
leaves (or other harness) above and below through ordinary suitable arrangements
of intermediate levers or "jacks" (or it might be direct or by cords and pulleys), so
as to produce the shed of the warp threads both up and down simultaneously, and
back to their normal or even position in the same plane, all in a positive manner,
thus giving a more regular and certain action to the heddles or harness than by the
springs or weights usually acting in one direction, and with less strain and wearing
friction on the heddles and warp than has been heretofore obtained. This new or
improved combination of shedding mechanism is also particularly suitable for the
weaving of gauzes or lenos at a higher rate of speed, and with greater ease on the
heddles and warp than hitherto obtained.
And in order that the full nature, novelty, and mode of performing my said
Invention may be properly understood, I shall now proceed to describe the several
Figures on the Sheet of Drawings which I have hereunto appended for the purpose
of showing the best modes and means I am at present aware of for putting the
Invention into effect or practice, the same reference letters and numerals indicating
the same or like parts in all the Figures where shown.
Figures 1 and 2 are respectively a side and a front elevation of an ordinary
power loom frame 1, 1, shown as fitted with one modification or combination of
the parts of my said new or improved portable positive shedding mechanism
secured on a suitable frame 11, 1", over the middle of the heddles Z for giving these
and the warp 2 their primary shedding motion through an arrangement of the
secondary or intermediate connecting jack levers, also showing one
arrangement of intermedite gearing 3, 3, and 4, 41, for actuating the same from
the crank shafts 5 of the loom, with the heddles and their moving mechanism in
the position of having formed the open shed of the warp 2; 2¹ being the warp
beam; 21, 2111, the cloth beams; and 5 and 6, the crank and cam shafts
respectively.

page_text: Figures 3, 4, and 5 are respectively a side elevation, an end elevation, and a
plan, all partly in section, of my said new or improved portable, positive, shedding
mechanism for looms for weaving, the same as shown in Figures 1 and 2, but here
drawn detached to half the full size to show its construction and action more clearly,
the whole being carried on two side frames F, F, secured together by the upper and
lower cross stays F1, F", carrying its revolving shaft E in bush bearings Fill in the
middle of the side frames F so as to give motion to all the other moving parts in
their proper sequential time, as will be herein-after explained.
Figure 6 is a side and edge elevation and plan of one of the draw rods or
links a as removed from and corresponding to the positions in Figures 3 to 5
respectively.
Referring to these Figures 1 to 6, and particularly to Figures 3, 4, and 5, the
essential novelty of the Invention and mode of carrying the same into effect consist
in fitting as many, preferably short thin flat metal draw rods a (as, say, from six
to twelve inches long, and from a fourth of an inch to one inch thick,) as there are
leaves or heddles Z (or transverse rows of harness) to be moved or shed in the loom,
and as close together as will suit these, edgeways, in separate slots, or close side by
side as convenient, within slotted carrying guides with holding-in plates at A" in or on
the back of two reciprocating drawing crossheads or bars A, A¹, which reciprocate
on the round guides B secured in snugs at B¹ of the frame F so as to work and guide
the draw rods a near their upper and lower ends (as seen in Figures 3 and 5)
reciprocating any required number of the draw rods a and their heddle leaves Z to
or from each other to form the shed, as seen in Figures 1 and 2, or place them all
in their normal level plane, as also the warp 2, jack levers z, 2, 21, and heddles Z,
ready for making another change and shed, preferably when the bars A and A¹ are
at the widest or extreme throw of their cams D, D', as seen in Figure 3, all by the
positive motion of these cross drawing bars A, A¹, actuated by antifriction pulleys A²
on their extreme ends beyond their slide guides B, where they project through
slots F in the side frames F into the double-acting groove C formed in the inner
face of each of the two cams D, D¹, keyed on the shaft E, and working close outside
the two side frames F secured together by cross stays F¹, F", to carry the
whole mechanism when made portable as preferred, and shown in Figures 3 to 5.
These cams D, D¹, are secured close to the side frames on the opposite ends of the
light constantly revolving shaft E carried in stationary bearings F formed in the
centre of the frame F between the slots Fabove and below for the reciprocating
cross bars A, A¹, to work out through, corresponding in character to that of the
drawing knives or "branders" of other "dobbies" and shedding mechanism. These
reciprocating bars A, A¹, have each a row of lateral holes or slots b formed through
them, fitted with locking bolts b¹, one opposite a check or notch a¹ near each end
of the draw rod a, preferably when the cross draw bars A, A¹, are at their extreme
furthest position from each other, where their rollers A2 are making the slight
pause in passing through the extreme throw of the curved part C¹ of the grooves C
of the cams D, D', so that the bolts b¹ can then enter the checks a¹ of the draw
rods a in this position by the action of their shifting or pattern needles G, G¹, (and
ordinary controlling cylinder H and cards I or other pattern mechanism), and so
lock each of the draw rods a to either their upper or lower drawing cross bars A
or A¹, as will be herein-after more particularly described.
may
The cam shaft E is driven by the intermediate shafts 3 and 4 through the
wheels 3 and 4¹ on the adjacent ends of their shafts respectively, from the crank
shaft 5 by the bevel wheels 51 on the near ends of the shafts 4 and 5, one pair of a
the wheels, as 41, being as one to two, so that the shaft E and cams D, D¹,
revolve at half the speed of the crank shaft 5, and as the cams D, D¹, are double
they produce two in-and-out movements of the cross drawing bars A, A¹, and their
locked draw rods a every revolution, equivalent to two sheds of the warp and
heddle leaves Z, which are drawn down through the two sets of proportionally
acting connected drawing beam levers or "jacks" and 21, the former z erected
above and connected at all to the drawing links a and the latter ¹ directly

page_text: connected at Z¹ to the leaves Z below respectively for pulling them down; and
through the two sets of single-armed levers 2 connected at a² to the lower ends of
the draw rods a above them, and at their extreme ends Z" direct to the top of the
heddle leaves Z below them, all by wires or cords. These levers or jacks 2,2', and 11,
are mounted on fixed standards ³, 111, and spindles zx, on the rails 111 (or other
frame parts 11, 2111, of the loom) carrying the frame F of the shedding mechanism
above (or below) the heddles Z, which they move, the number of levers in each
set 2,2,2, corresponding to that of the leaves Z of the warp threads and of the
locking draw links a which primarily move them through their several connecting
wires or cords a¹¹, a², z, Z, Z", The upper and lower ends of each draw link
or rod a are connected direct or by a hook through the wire, cord, or other
equivalent a, a, to the inner arm of each corresponding lever of the upper set of
levers or jacks, and to the middle of each lever of the lower set 211 respectively.
The free ends of the outer arms of the levers are so connected by wires ³ (or
other equivalent) to the lower levers 2¹ of the heddles Z connected by wires Z' below,
while the free end of each lever z¹¹ is directly connected by a wire Z¹¹ to the top of
its corresponding heddle leaf Z, all so as to give the heddles their full shed of from
three to five inches, as desired, through the proportional lengths of the connecting
arms of these levers z, z¹, and z¹¹, to that of the "throw" of the grooves C, C, of the
cams D, D¹, and drawing cross bars A, A¹, moved by these, and which is preferred
to be about an inch or inch and quarter on each bar a, giving the combined motion
inwards of two inches or two inches and a half on the drawing rods a and inner
connected parts or arms of the primary levers z, 21, to produce the full stroke of the
ends of the levers ¹ and ¹ directly connected to the heddles Z to give them their
full shed. The outward position of the draw bars A, A³, correspond to the level or
even position of the levers and warp, as before stated.
The said locking of the moving cross bars A, A¹, to the draw rods a sliding through
the slots in them is effected by the outer ends of the locking bolts b¹, which have
each an eye in them at 611 (or other equivalent attachment) sliding freely on the
kneed stem g of their moving or locking and unlocking needles G and G¹ during
their motion in and out with the cross bars A, A¹, and so as to be moved by one
(preferably the upper) set of needles G direct. Each set of needles G, G', is carried
and guided in the two stationary plates f secured to the inner front part of the
frames F nearly in front of the locking bolts b¹ and bars A, A¹, when in their said
outer changing and locking position, the front horizontal stems of the needles G, G¹,
working through two horizontal rows of holes equally divided transversely, the one
row above the other, preferably alternately, or in the centre between each other, and
through which they are moved by the forward motion of the ordinary jacquard
barrel H and pattern chain of cards I revolving in the upper free ends or arms J of
the rocking lever frame J, J, carried in adjustable pivots J" in the lower part of
the two side frames F, F, in front of and with the centre of the barrel H and
acting cards I held opposite the forward projecting ends of the upper set of needles G
by the kneed lever Hand spring H², or other equivalent; but other pattern or
pegged pattern barrels or endless chains may be used to actuate these needles.
Each needle G is connected to its corresponding needle G¹ placed vertically below it
of the lower set G¹ by one of a set of light two-armed vertical levers g oscillating
on the fixed centre spindle g¹, and having their ends passed through eyes in their
respective needles G, G¹, at g³, these levers g being each fitted with a light spiral
spring g and regulating pressure screw pin g" carried in the cross rail g³, which
thus bring both sets of needles G, G¹, out to their normal vertical plane and position
as well as their locking bolts b', which they actuate, with the inner ends of the
bolts quite into the checks a² and clear of the upper checks a¹ of each link a,
when left free to do so at the time the drawing cross bars A, A¹, are at their
outward position through the screw pins f¹ secured in the top F1 of the frame F
pressing down the spring locking plate c carried and sliding on the two stems c¹
secured to and pendent from the front side of the upper bar A, and fitted with the
springs c¹ below the plate and adjusting pressure nuts c³ at their lower ends which

page_text: press up the plate c between the retaining pins 63 on the under side of each of the
locking bolts 61 as they have been set by their needles G, and the usual oscillation
of the cylinder H and pattern card I present for the time being the first movement
or lowering of the bar A, releasing the fixing blade or plate c from the action of the
pins f, so that it locks all the top bolts as set into or out of the bar A and
upper notches a¹ of the links a, and vice versa all those of the lower bar A¹ set out
or into the notches a¹ of the same links a by the action of the levers g and
springs g, which latter besides pressing in all the lower locking bolts b¹ not drawn
out by the pattern card and upper needles G draws and keeps out their corres-
ponding bolts of the upper set not pushed in; all so that each draw link a is
either linked to its upper or lower drawing bar A or A', and thus, as before stated,
pulls down and draws up their corresponding heddle leaves Z and forms the shed of
the warp, as shown in Figure 1, all by the positive motion of the cam grooves C in
the cams D, D¹.
To give the said motion or pressing in action to any number of the upper set of
needles G (to suit the desired pattern shed of the heddles) the pattern barrel H has
each of its four sides pierced with a set of holes h corresponding to that of the
needles G, and each pattern card I of the chain or set, made of thin sheet metal or
strong cardboard is pierced with a hole through it opposite each needle not re-
quired to be pushed forward by it, but allow them to pass into the holes in the
barrel when it is brought forward to push back the needles where the card is not
pierced so as to produce the particular shed of the heddles Z, as herein-before
described, due to and regulated by the particular card I brought into action,
essentially by the ordinary reciprocation of the carrying frame J, J¹, of the barrel
H actuated as will herein-after be particularly described.
The frame J, J, is preferably actuated by an improved construction of cam K, K¹,
formed on the outer perimeter of one of the cams D, D¹, (or it might be a separate
cam on their shaft E) and which by its cam surface K'acts on the antifriction
pulley carried on the stud arm 7 secured to one arm J of the frame J, J, and
presses out this frame so as to turn the barrel H and bring up a new pattern card I
on the outward stroke by the usual turning pawl H" hinged to the regulating
screw joint bracket H (while the cams C, D, C, D, are drawing the bars A, A¹,
and making the shed) against the power of the spring secured at its inner end to
a hook at j¹¹ in the top F¹ of the frame F, and at the other end to the eye js
secured to the upper part of one arm J of the rocking frame J, J, and which keeps
the pulley j always up against the cam K; and at the inner part of the motion of
the cam K and frame J, J, causes the pattern barrel H and card I on it to press in
all the needles G where there are no holes pierced in the card; and their locking
bolts require to be locked into the upper notches a¹ of their draw links a direct
to the upper drawing bar A by the power of the spring j" assisted by the improved
outer segmental cam rims K', which draw in and retain the pulley ; against the
power of the springs gl acting through their levers g which keep out all the other
needles G not so pushed in, at the same time locking all the lower ends of the links
a to the lower drawing bar A¹ not locked to the upper bar A. And while this
locking of the links a to either of the draw bars A or A¹ is taking place, at each
half revolution of the cams D, D¹, and K, K', and outer throw of the former and
inner throw of the latter, one or other of the segmental groove parts K¹ of the
latter holds the card barrel H, which made the change, quite up until the cam
grooves C¹ bring down the upper bar A sufficient to allow the locking plate c to
enter between the shifted row of pins 62, 62, to lock and hold the bolts in while the
draw bars A, A', and link a are making the shed of the whole of the heddle leaves
or warp threads either up or down, all in a positive manner, as herein-before
described, ready for each pick of the shuttle, and back again to the normal straight
or level position for the beating up of the weft, and making the next change of
needles G, G¹, and heddles Z.
Instead of carrying the locking blade or plate c on the reciprocating draw bar A,
and locking the bolts b' by the pins 62 on their under side, this may be done, as

page_text: shown dotted in in Figure 3, by a locking blade or plate c* carried on the front
ends of a two armed light lever frame c¹¹¹ oscillating on fixed studs at the back c³ of
the upper frame FI above the upper bar A, so that the lower edge of the locking
plate ex by its own weight would always fall in between the upper ends of the
coupling and reacting levers g of the needles G and G', and lock them as soon as
they had been shifted and set, as before stated, by the springs gland the pattern
cards and barrel I, H, and always lifted out of the space between the ends of the
lever g in time to be shifted by the barrel and cards at the inner part of their
stroke by a stud et projecting up from the cross bar A, which at the upper part of
its motion would act on one or both of the levers c¹11 so as to lift the locker c* out
of action and let it down again as soon as the needles G, G³, were shifted at the
first part of the descent of the bar A.
This new or improved positive shedding mechanism when made portable as shown
on the frame F may be arranged to work in other positions than that shown over
the heddles either below or at the side of the loom, and so acting at other angles as
may be desired to suit particular looms, and have a set of primary levers carried on
brackets at the upper and lower parts of the frame F directly connected at their
inner ends to the upper and lower ends of the draw links a and having the free
ends of these levers connected by wires or cords to other levers, or led over pulleys
so as to work the shedding heddles or harness, or the actuating "jacks or levers
of these, all otherwise substantially in the positive manner herein described in
reference to the arrangement shown in the Drawings.
This improved positive shedding mechanism (as shown in Figures 3, 4, and 5) is
also most suitable for working the usual shedding heddles for weaving gauzes and
lenos by retaining the present fore parts of the heddles used for weaving these
fabrics, and converting what is usually termed the back parts of the heddles into fore
parts by the introduction of "doups" or half heddles into them by bringing these
two sets of fore parts close together instead of working them at a certain distance
apart as heretofore practised, and attaching them to the draw rods of the machine
as before described, the "doups" or half heddles being attached to the upper or
under end only of their respective rods, as may be required for constantly raising or
sinking each "doup" or half heddle, and by the positive action of the mechanism
bringing the "doups" or half heddles to their original plane and retaining them there
without the intervention of weights or other appliances as heretofore practised. And
by alternately opening and closing the "doup" or half heddle in each set in oppo-
sition to each other the cross on the threads in a gauze or leno is formed and the
warp springs clear behind and before the heddles as in a common jaconette. The
portable nature of this shedding mechanism also renders it most suitable for easy
removal and attaching another in a few minutes when anything goes wrong with it
or its pattern gear with very little stoppage of the loom.
Having now described the nature of my said Invention and the manner of per-
forming the same, I have to state that I do not confine myself to the precise details
herein described or delineated, but what I consider novel and original and therefore
claim as the Invention secured to me by the herein-before in part recited Letters
Patent is,-
First. The general construction and arrangement or combination of mechanism
carried on the portable frame F, F1, F", and its driving gear and arrangement of
levers or "jacks" (or other equivalent) for the actuating of the heddles and shedding
of the warp by a positive motion in both directions in looms for weaving, all sub-
stantially as herein described in reference to and shown in the accompanying
Drawings or any mere modification thereof.
Second. The construction and use of a shedding mechanism-for- looms for
weaving having two reciprocating or drawing cross bars A, A', with drawing links a
locked to one or other of these for producing a positive shedding action in both
directions, preferably by a duplex cam on each side directly connected to the bars,
all substantially as herein described in reference to and shown in the accompanying
Drawings, or any mere modification thereof.

page_text: Third. The construction and use of a shedding mechanism controlled by a single
pattern barrel for each change or shed with a double set of connected needles G, G¹,
actuating the locking bolts b' for fixing the drawing bars A, A¹, thereof to their
draw links a for giving a positive shedding action in both directions to the heddles
or warp in looms for weaving, all substantially as herein described in reference to
and shown in the accompanying Drawings, or any mere modification thereof.
Fourth. The locking of the two sets of pattern needles G, G₁, or their locking
bolts b¹ after each shift or change by one automatic acting cross blade, plate, or
bar cx or c of a duplex positive shedding mechanism for looms for weaving, sub-
stantially as herein described in reference, to and shown in the accompanying
Drawings or any mere modification thereof.
In witness whereof, I, the said William McIlwraith, have hereunto set my
hand and seal, this Fourth day of May, in the year of our Lord One
thousand eight hundred and seventy-seven.
Witness,
W. R. M. THOMSON,
Patent Agent,
Glasgow.
WILLIAM MILWRAITH. (L.S.)