IMPROVEMENTS IN POWER LOOMS
Year: 1868

page_text: LETTERS PATENT to Matthew Andrew Muir and James McIlwham,
both of Glasgow, in the County of Lanark, North Britain,
Machinists, for the Invention of "IMPROVEMENTS IN POWER LOOMS."
Scaled the 3rd November 1868, and dated the 7th May 1868.
PROVISIONAL SPECIFICATION left by the said Matthew Andrew Muir
and James M'Ilwham at the Office of the Commissioners of Patents,
with their Petition, on the 7th May 1808.
We, MATTHEW ANDREW MUIR and JAMES MILWHAM, both of
Glasgow, in the County of Lanark, North Britain, Machinists, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN
POWER Looms," to be as follows, that is to say:-
This Invention relates to improvements in various parts of power
looms, and has generally for its object to improve the working, to
diminish concussions, and to render such looms better adapted than
heretofore for weaving light and delicate fabrics.
A first improvement is applicable to what is known as the "under"
picking motion, and consists in applying a parallel motion to the picking

page_text: stick, and in adapting a spring thereto in such a way as to gradually
resist the continuation of the stick's movement after throwing the
shuttle, and so as to act as a check upon the shuttle when coming home
into the box by holding the stick at a short distance in from the end
of the box. With this arrangement a comparatively light picking
stick may be used and is fixed in a metal holder at the bottom, which
holder is formed with a groove or slot so that it can slide up and
down on a pin projecting from a casting fixed on the lathe axle, whilst
at a point above the slot the holder has jointed to it the bottom end
of a short link, the upper end of which is jointed on a second pin on
the casting. These parts constitute a "parallel motion," and cause the
upper end of the picking stick where it acts on the driver to move in
a straight line, and there is in consequence much less liability to tilt
and throw out the shuttle than with the ordinary arrangement wherein
the end of the picking stick moves in an arc. A spiral spring having
its bottom end hooked on a pin on the casting on the lathe axle has
its upper end hooked on a pin on the stick holder. This spring is at
its shortest when the picking stick is standing a short distance inwards
from the end of the shuttle box, and it is slightly stretched by the
outward movement of the stick by which it checks the shuttle when
entering; then on the picking stroke taking place the spring assists it
at first, is next neutral, and afterwards resists it from being stretched
over to the other side, but the resistance begins very slight and then
increases more and more rapidly. Thus without taking anything from
the smartness of the picking stroke, the momentum of the picking stick
is afterwards gradually and speedily absorbed so as to diminish the
concussion as much as possible.
These improvements are applicable with various kinds of "under
picks," but it is preferred to use the kind in which steel strikers
carried by arms on the low shaft act on steel pieces in arms on short
shafts connected to the picking sticks by straps fixed to spiral bosses,
.and the steel pieces are made like bevil teeth which have always more
surface in contact when in action than the square pieces ordinarily
employed.
A second improvement consists in arranging parts in connection with
a loose reed and shuttle-box protectors, so that on the shuttle failing
to reach its box a locking detent is set free, and a spring either sets
the reed free or actually moves it back, so that when the shuttle stops

page_text: in the shed the warps cannot be injured by any pressure such as that
to which in ordinary arrangements the shuttle is subjected in forcing
back the reed. The keeper bar which holds in place the bottom of the
reed is as usual carried by arms on a rocking spindle which is carried
beneath the lathe, but a spring is applied to the spindle to give it a
tendency to open back the keeper bar and release the reed, or the
keeper bar may be connected to the bottom of the reed so as to draw
it back. The spindle is prevented from yielding to the action of the
spring by a notched lever which is centred on a stud and acted on by
a spring so as to retain a catch arm fixed on the spindle as long as the
loom works properly. Each shuttle box is provided with the usual
swell lever and also with the jointed back, and the ordinary springs may
be applied to the backs of these, or such springs may be dispensed with.
A light horizontal rod or protector spindle is arranged behind the lathe
and has fixed on it levers with adjustable screw fingers which are
pressed against the swell levers by the action of a spring applied to
the spindle. A horizontal arm is fixed on the protector spindle, and
bears up a finger jointed to the notched lever and which projects
forward, and on the lathe beating up carries it over a catch piece fixed
to the loom framing when the loom is working properly; this it is
enabled to do because of the presence of the shuttle in the box pressing
back the swell lever, which bearing on one of the levers on the protector
spindle causes it to turn and raise up the arm projecting in front.
When, however, the shuttle does not get properly into the box, the
arm projecting in front is not raised, and the finger of the notched
lever encounters the catch piece and the notched lever is pushed back
and releases the spindle, whereupon the keeper bar is turned back by
the action of the spring, as herein-before described. The hinged part
of the back of the shuttle box may be linked to the lever or arm on
the protector spindle, so as to be drawn back when the reed is released
and so as to completely relieve the shuttle when caught partly in the
shuttle box and partly in the shed. In some cases the protector spindle
may have fixed on it at each side of the loom an arm and adjustable
finger to bear against the hinged back of the shuttle box instead of a
separate spring bearing thereon, and instead of connecting the hinged
back to an arm on the protector spindle or on the keeper-bar spindle
these two spindles may be connected so as to turn back together, which
will take the pressure off the hinged back of the shuttle box when the
shuttle does not enter properly.

page_text: In another modification of parts for effecting the same thing as those
herein-before described the keeper-bar spindle has fast on it an arm
carrying a catch which a spring tends to keep in the way of a rod
made to reciprocate by means of a cam on the low shaft. An arm fixed
on the protector spindle puts this catch out of the way of the recipro-
cating rod whenever the shuttle gets properly into its box, but when
this does not occur the reciprocating rod encounters the catch and
through it turns back the spindle and keeper bar and so releases the
reed. In this case the spring is applied to the keeper bar or its spindle
so as to tend to keep it closed.
A. third improvement relates to the manner of actuating the vibrating
rail used for relieving the strain on the warps which the shedding
action tends to produce, and consists in shaping the cams that act and
in arranging the levers and connections that communicate the action
to the rail in such a manner as to keep the tension on the warps as
uniform as possible. As the warps are drawn from the middle line by
the shedding action the lengths from the points of separation vary as
the joint pairs of secants of the successive angles assumed, and such
variation being measured from a diagram drawn from any particular
case the shape of a cam to impart to the rail a movement corresponding
thereto.is determined by well-known methods of delineation.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Matthew Andrew Muir and James M'Ilwham in
the Great Seal Patent Office on the 6th November 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, MATTHEW 2
ANDREW MUIR and JAMES MILWHAM, both of Glasgow, in the County
of Lanark, North Britain, Machinists, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of May, in the year
-of our Lord One thousand eight hundred and sixty-eight, in the s
thirty-first year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said Matthew Andrew Muir and James
McIlwham, Her special licence that we, the said Matthew Andrew
Muir and James M'Ilwham, our executors, administrators, and assigns,

page_text: or such others as we, the said Matthew Andrew Muir and James
McIlwham, our executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN POWER Looms," upon the condition (amongst
others) that we, the said Matthew Andrew Muir and James M.Ilwham,
our executors or administrators, by an instrument in writing under our,
or their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that we, the said Matthew Andrew Muir and
James McIlwham, do hereby declare the nature of our said Invention,
and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement in writing,
reference being had to the accompanying Drawings, that is to say :--
Our said Invention relates to improvements in various parts of power
looms, and has generally for its objects to improve the working, to
diminish concussions, and to render such looms better adapted than
heretofore for weaving light and delicate fabrics.
And in order that our said Invention and the manner of performing
the same. may be properly understood we have hercunto appended two.
Sheets of explanatory Drawings to be herein-after referred to, and
representing our improved mechanism, together with such known parts.
of the loom as are in immediate connection with it.
Figures 1 and 2, on Sheet 1 of the Drawings, are a sectional front
elevation and a. sectional side elevation of the loom, whilst the other
Figures represent detached parts, and will be herein-after specially
noticed. The same reference letters and numerals are used to mark the
same or like parts in all the Figures in which they occur.
Our first improvement is applicable to what is known as the "under"
picking motion, and consists in applying a parallel motion to the picking:
stick P, and in adapting a spring 1 thereto in such a way as to gradually.
resist the continuation of the stick's movement after throwing the
.

page_text: shuttle, and so as to act as a check on the shuttle when coming home
into the box B by holding the stick Pat a short distance in from the
end of the box. With this arrangement a comparatively light picking
stick may be used, and is fixed in a metal holder 2 at the bottom,
which holder is formed with a groove or slot so that it can slide up
and down upon and be guided by a pin 3 projecting from a casting 4
fixed on the lathe axle 5, whilst at a point 6 above the slot the holder 2
is jointed to the bottom end of a short link 7, the upper end of which
is jointed on a second pin 8 fixed in the upper part of the casting 4.
This casting 4 with the link 7 is shown detached and in face view in
Figure 8. These parts constitute a "parallel motion," and are so pro-
portioned as to cause the upper end of the picking stick P where it
acts on the driver d to move in a straight line, and there is in con-
sequence much less liability to tilt and throw out the shuttle than with
the ordinary arrangement, wherein the acting end of the picking stick
moves in an arc. The spring 1, which is represented as a spiral one,
but which may be of any suitable kind, has its bottom end hooked on
an adjustable stud on the casting 4 on the lathe axle 5, whilst its upper
end is hooked on a stud formed on the upper part of the stick holder 2.
This spring 1 is at its shortest when the picking stick P is standing in
the position shown in Figure 1, namely, at a short distance inwards
from the outer end of the shuttle box B, and it is slightly stretched
by the outward movement of the stick P by which it checks the shuttle
when entering. Then on the picking stroke taking place the spring 1
assists it at first, is next neutral, and afterwards resists it from being
stretched over to the other side, but the resistance begins very slight
and then increases more and more rapidly. Thus without taking any-
thing from the smartness of the picking stroke the momentum of the
picking stick is afterwards gradually and speedily absorbed so as to
diminish the concussion as much as possible.
These improvements are applicable with various kinds of "under
picks," but we prefer to use the kind in which steel strikers 9 carried
by arms 10 on the low shaft L act on steel pieces 11 fixed in short
shafts 12 connected to the picking sticks P by straps 13 fixed to spiral
bosses 14 on the shafts 12. Figure 3 is a plan of these parts as inverted.
We shape the steel pieces 9, 11, like bevil teeth, as shown, and they
have in consequence always more surface in contact when in action than
the square pieces ordinarily employed.

page_text: Our second improvement consists in arranging parts in connection with
a loose reed R and shuttle-box protectors, so that on the shuttle failing
to reach its box B a locking detent is set free, and a spring either
sets the reed free or actually moves it back, so that when the shuttle
stops in the shed the warps cannot be injured by any pressure such as
that to which in ordinary arrangements the shuttle is subjected in
forcing back the reed. The keeper bar 15, which holds in place the
bottom of the reed R, and which is best seen in the transverse vertical
sections, Figures 6 and 7, is as usual carried by arms on a horizontal
rocking spindle 16 which is carried beneath the lathe, but a spring 17
is applied to the spindle, being hooked to a short arm thereon to give
it a tendency to open back the keeper bar 15 and release the reed R;'
or the keeper bar 15 may be connected by a link to the bottom of the
reed R so as to draw it back. The reed is shown as moved back in
Figure 6, and as in its working position in Figure 7. The spindle 16
is prevented from yielding to the action of the spring 17 by a notched
lever 18 which is centred on a stud on the latho sword 19 and acted
on by a spring 20, which by turning it forwards makes it retain a catch
arm 21 fixed on the spindle 16 as long as the loom works properly.
Each shuttle box B is provided with the usual swell lever 22, and also
with the jointed back 23. These parts are shown complete at one side
only of the loom, but it will be understood that similar parts are to be
applied at the other side, so that the same actions may take place
towards whichever side the shuttle is being thrown.
Figure 4 is a top view of the shuttle box corresponding to Figure 5,
which is a back view, and which is drawn as projected at right angles
from Figure 2. The movable part 23 of the shuttle-box back is hinged
or jointed to the other part by steel plates 24, which serve also as
springs, and are so set as to give the back 23 a tendency to open back-
wards into the position indicated by dotted lines in Figure 4. A light
horizontal spindle or protector rod 25 is carried in the lathe swords 19
a little behind and below the keeper-bar spindle 16, and has fixed on
it at each side a lever 26 with an adjustable screw finger, which is
pressed against the swell lever 22 by the action of a spring 27 applied
to the rod 25. A horizontal arm 28 is fixed on the protector rod 25
so as to project forward alongside of the notched lever 18, which prevents
the release of the reed when the loom works properly, as herein-before
described. The protector rod arm 28 has its front end bent at a right

page_text: angle to enter under and bear up a finger 29 jointed to the notched
lever 18, whilst a blade spring applied above keeps the parts in contact.
The finger 29 jointed to the notched lever 18 projects forward, and on
the lathe beating up is carried over a catch or stop piece 30 fixed to
the loom framing when the loom is working properly; this it is
enabled to do because of the presence of the shuttle in the box pressing
back the swell lever 22, which bearing on one of the levers 26 on the
protector rod 25 causes that rod to turn and raise up the arm 28
projecting forward. When, however, the shuttle does not get properly
into the box, the arm 28 is not raised, and the finger 29 of the notched
lever 18 encounters the stop 30 when the lathe beats up, and the
notched lever is as it were pushed back; this sets free the catch of the
arm 21 from the notch, and the keeper-bar spindle 16 on which that
arm is fixed is thus released, and is instantly caused by the action of
the spring 17 to turn back the keeper bar 15, and thereby relieve the
reed R. The keeper-bar spindle 16 has fast on it near each end
a lever 31 fitted with an adjustable screw finger which bears against the
movable back 23 of the shuttle box, and keeps it closed when the loom
is working properly; but on the shuttle not getting properly home.the
same movement which, as herein-before described, releases the reed
also moves back the levers 21, and the backs 23 then open back by the
spring action of their hinge plates 24. In a somewhat similar manner
the pressure of the protector arms 26 on the swell levers is removed
when the keeper-bar, spindle 16 turns to release the reed, this being
done by the action of the parts best seen in Figures 6 and 7. Short
levers or arms 32, 33, are fixed on the spindles 16, 25, and are connected
by a link 34, whereby the spindle 16 on turning back causes the
protector rod or spindle 25, to turn back also, the superior strength of
the spring 17 overcoming the spring 27. The link 34 is slotted to
allow of the free action of the protector rod 25 which turns up the
lever 33 a short distance when the shuttle gets properly home, and
presses back the swell lever 22.

page_text: loosely and be linked to the lever 31 on the keeper-bar spindle 16 so
as to be drawn back thereby when the reed is released. After the shuttle
has been caught and the reed released by the herein-before described
mechanism the parts can all be replaced by the simple action of
depressing the catch lever 21 or another conveniently situated lever 35
fixed on the keeper-bar spindle 16.
In another modification of parts for effecting the same thing as those.
last herein-before described the keeper-bar spindle 16 has fixed on it.
an arm carrying a catch which a spring tends to keep in the way of
a rod made to reciprocate by means of a cam on the low shaft L. An
arm fixed on the protector rod or spindle 25 puts this catch out of the
way of the reciprocating rod whenever the shuttle gets properly into.
its box, but when this does not occur the reciprocating rod encounters
the catch, and through it turns back the spindle 16 and. keeper bar 15,
and so releases the reed R. In this case the spring 17 is applied to the
keeper bar or its spindle so as to tend to keep it closed.
Our third improvement relates to the manner of actuating the
vibrating rail V used for relieving the strain on the warps which the
shedding action tends to produce; and it consists in shaping the cams 36
that act and in arranging the levers 37 and connections 38 that com-
municate the action to the rail V in such a manner as to keep the
tension on the warps as uniform as possible.
Figure 9, on Sheet 2 of the Drawings, is a full-size diagram showing
the various positions of the warps during the shedding action in an
assumed example in which the heddles rise or fall at a uniform rate.
If the warp threads were divided at the heddles their ends would
obviously describe the circle arcs 39, 39, and 40, 40, on being drawn
from the horizontal centre line W, W, into the various angular positions;
but being undivided the lengths from the points of separation vary as
the joint pairs of secants of the successive angles assumed; in other
words, each warp thread requires in each position an increase of free
length equal to the sum of the two angular lines which lying between
the two circle arcs 39, 39, and 40, 40, meet at the middle. vertical.
line 41, 41. The increases of length being obtained by the diagram,
Figure 9, a cam 36, such as is shown in Figure 10, may have its shapo
determined therefrom by well understood methods of delineation, so as

page_text: to impart to the rail V a movement which will let forward and draw
back the warps in close accordance with the shedding movements so
as to maintain them at as uniform a tension as possible. Thus the
ratio that the movement of the point of the lever 37 acted on by the
cam 36 bears to that of the top of the rail V having been ascertained
one of the four symmetrical sets of the angular lines of the diagram,
Figure 9, are extended, as shown by the red lines, in a corresponding
proportion and a corresponding circle arc 42, 42, and vertical line 43, 43,
are drawn. Then the lengths of the angular lines between the arc and
vertical line will measure the respective heights to which the lever 37
has to be lifted by the cam 36, and at the same time the positions 44
on the radial lines of the cam diagram, Figure 10, of the centre of the
pulley on the lever 37. From these positions the contour of the cam
is determined in the ordinary way, the cam being of course divided by
the radial lines, so that its action keeps time with the shedding action.
There are two of the cams 36 on the low shaft L, and these act on
two levers 37 which are centred on brackets fixed to a horizontal frame
bar at the back of the loom, springs 45 being applied to keep the lever
rollers in contact with the cams. The levers 37 are connected by
adjustable links 88 to arms 46 fixed to the vibrating rail V.
Having thus particularly described our said Invention, and the
manner in which the same is to be performed, we have to state that
we do not restrict ourselves. to the precise details herein described or
delineated; but that what we believe to be novel and original, and claim
as the Invention secured to us by the herein-before in part recited
Letters Patent is,--
1. The arranging of the picking stick so that its acting end moves
in a straight line; the applying of a spring so as to be neutral when
the picking stick is at a short distance within its outermost position,
and so as to act with increasing resistance as the picking stick completes
its stroke; and the bevilling of the steel strikers of the picking motion,
all substantially in the improved modes herein-before described.
2. The arranging and combining together of the parts in connection
with a loose reed substantially in the improved manner herein-before
described, and more particularly the setting of the reed free without
straining the warps when the shuttle is caught, whilst at all other times
it is rigidly locked.

page_text: 3. The actuating of the vibrating rail for accomodating the warps
to the shedding action by means of cams shaped from diagrams of that
action, subtantially as herein-before described.
In witness whereof, we, the said Matthew Andrew Muir and
James McIlwham, have hereunto set our hands and scals, this
Fourth day of November, in the year of our Lord One thousand
eight hundred and sixty-eight.
10 Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
MATTHEW A. MUIR. (L.S.)
JAMES MILWHAM.
(L.S.)