IMPROVEMENTS IN LOOMS FOR WEAVING
Year: 1869

page_text: LETTERS PATENT to Matthew Andrew Muir and James McIlwham, of
Glasgow, in the County of Lanark, North Britain, Machinists, for
the Invention of "IMPROVEMENTS IN LOOMS FOR WEAVING."
Sealed the 31st August 1869, and dated the 9th July 1869.
PROVISIONAL SPECIFICATION left by the said Matthew Andrew Muir
and James McIlwham at the Office of the Commissioners of Patents,
with their Petition, on the 9th July 1869.
We, MATTHEW ANDREW MUIR and JAMES MILWHAM, of Glasgow,
in the County of Lanark, North Britain, Machinists, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN LOOMS FOR WEAVING,"
to be as follows, that is to say :-
This Invention relates to mechanism whereby the shuttle boxes of
looms when arranged for weaving with two or more shuttles are auto-
matically shifted. in accordance with predetermined patterns, and the
present improvements are intended to be used in concert with perforated.

page_text: pattern cylinders and accompanying details such as are described under
various modifications in the Specifications of five Patents having the
distinguishing numbers 2823 of the year 1853, 161 of 1854, 1437 of
1856, 2581 of 1858, and 87 of 1861, and granted the first two to Matthew
Andrew Muir, one of the present applicants, and the others jointly to
both of the present applicants. The said improvements may however also
be used with any suitable pattern mechanism capable of imparting to
certain comparatively small, light, and balanced details slight changes
of position corresponding to the required shifts of the shuttle box.
In applying the present improvements the spear or vertical rod which
is fixed at its upper end to the shifting shuttle box is at its lower end
jointed to the front end of a lever centred on a stud upon the outside
of the side frame of the loom. This lever is formed with an arc or bar
shaped concentrically with its fulcrum and fitted with two shifting catch
pieces, through which the lever receives the action of two pawls con-
stantly reciprocating towards and from each other by the action of a
cam on the low or second motion shaft of the loom. The catch picces
are centred on studs on the side of the lever or arc, and are each formed
with several notches corresponding to the number of cells in the shuttle
box, whilst they are connected together by a link jointed to bell-crank
arms formed on them, so that they balance cach other, and so that as
one rises the other falls. The pawls which shift the lever slide on the
edge of the arc, and engage with different notches of the catch pieces
according to the positions these pieces happen to be in when the pawls
move towards each other. Each pawl will in fact engage with that notch
of the corresponding catch piece which happens to be level with the
edge of the arc. In consequence of the catch pieces being connected
as herein-before described, it follows that when one piece is shifted into
a position to engage nearer the middle of the are the other one will
engage further from the middle, and the distance between the opposite
engaging notches will always be the same and equal to the distance
between the pawls when nearest together. Thus the pawls will always
hold the lever steadily and firmly between them when they approach
each other, and they will give a positive motion to the lever in either
direction, for when the back pawl encounters a catch before it reaches
the inner end of its stroke it will turn the lever so as to lower the
shuttle box, whilst if the front pawl encounters a catch when moving
inwards it will turn the lever so as to raise the shuttle box, and

page_text: The cam
whenever one catch piece is being thus acted on the other is necessarily
in a position to engage with the other pawl just as that other pawl
completes its inward stroke, and thus prevent the lever from being jerked
too far. The catch pieces are shifted by a link jointed to either of them
at one end and at the other to the end of a small lever which in its
middle position is in the axial line of the main lever, and this small lever
is actuated by the cylinder or other pattern mechanism. The pawls
which act on the main lever are jointed to vertical or pendent arms of
two bell cranks set on studs with horizontal arms extending towards
cach other, and these horizontal arms are actuated together by a cam on
the second motion shaft. The pendent and horizontal arms of each
bell-crank lever are in separate pieces connected by a strong spring (an
arrangement already applied to the lever for actuating the pattern
cylinder), and it allows the parts to yield so as to avoid breakage when
any accidental obstruction to the action of the parts occurs.
for acting on the bell-crank levers may be constructed to give a
maximum shift of two, three, or other number of shuttles at once
irrespective of the total number of shuttles employed, or a differential
cam may be used, such can being fitted to slide along the shaft to bring
differently proportioned parts into action on the levers as may be
required. In all cases, whatever may be the maximum shift the cam
can give, any less shift will be given by the mere action of the pattern
mechanism on the catch pieces. A spring is applied to the main lever
to counteract the weight of the shuttle boxes, being connected to a pin
situated on the lever in a position which reduces the leverage effect of
the spring as it is extended so as to make its action as nearly uniform as
possible. The main lever is prevented from shifting, whilst the pawls
are receding from each other for a fresh stroke by a lever friction brake
which is applied to the arc of the lever and pressed against it by a cam,
but this cam is shaped so as not to press the brake at the periods when
the lever may be shifted. A pad or block of wood, leather, or other
suitable material is fixed to the brake lever to bear on the arc, and the
lever is made to spring, or a spring is otherwise applied so as to com-
pensate for any slight wear of the pad or block and thus obviate the
necessity of frequent adjustments by the tenter.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Matthew Andrew Muir and James McIlwham in
the Great Seal Patent Office on the 7th January 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, MATTHEW
ANDREW MUIR and JAMES MILWHAм, 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 Ninth day of July, in the year of our
Lord One thousand eight hundred and sixty-nine, in the thirty-third
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.
McIlwham, our executors, administrators, and assigns, 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 "Im-
PROVEMENTS IN LOOMS FOR WEAVING," upon the condition (amongst others)
that we, the said Matthew Andrew Muir and James McIlwham, 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 sanie 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 mechanism whereby the shuttle boxes
of looms when arranged for weaving with two or more shuttles are
automatically shifted in accordance with predetermined patterns, and
our present improvements are intended to be used in concert with per-
.

page_text: forated pattern cylinders and accompanying details, such as are described
under various modifications in the Specifications of five Patents having
the distinguishing numbers 2823 of the year 1853, 161 of 1854, 1437
of 1856, 2581 of 1858, and 87 of 1861, and granted the first two to
Matthew Andrew Muir, one of us, and the others jointly to. both of us.
Our said present improvements may however also be used with any
suitable pattern mechanism capable of imparting to certain com-
paratively small, light, and balanced details slight changes of position
corresponding to the required shifts of the shuttle box.
And in order that our said Invention, and the manner of performing
the same, may be properly understood, we have hereunto appended a
Sheet of explanatory Drawings to be herein-after referred to and
representing a loom as constructed and fitted with our improvements.
Figure 1 is a plan of one side of the loom, and Figure 2 is a side
elevation.
Our present improvements may be used with shifting shuttle boxes
of various kinds, but in applying them in connection with boxes of the
vertically sliding class the spear or vertical rod 1, which is fixed at its
upper end to the shifting shuttle box 2 and serves to support and shift
it, is at its lower end jointed to the front end of a lever 3 centred on a
stud at 4 upon a frame or bracket a fixed on the outside of the side
frame 5 of the loom. This lever 3 is formed with an arc or bar 6 shaped
concentrically with its fulcrum and fitted with two shifting catch
pieces 7, 8, through which it receives the action of two pawls 9, 10,
constantly reciprocating towards and from each other by the action
of a cam 11 on the low or second motion shaft 12 of the loom.
The catch pieces 7, 8, which are in the form of levers, are centered
on studs 13 on the side of the lever 3 or are 6, and are each formed with
several notches arranged step-ways and corresponding to the number of
cells in the shuttle box, whilst they are connected together by a link 14
jointed to bell-crank arms formed on them, so that they balance or
partially balance each other, and so that as one rises the other falls.
The modification delineated is constructed for six shuttles, but it is
not necessary for the catch pieces 7, 8, to be formed with six notches, as
one notch for each extreme position may be formed on a projection 15
on the arc 6, the catch pieces thus requiring to have each only five
notches, or one less than the number of shuttles whatever that number
may be, it being understood that our improvements may be arranged

page_text: for any convenient number of shuttles. The pawls 9, 10, which shift
the lever 3 slide on the edge of the arc 6, and engage with different
notches of the catch pieces 7, 8, according to the positions these pieces
happen to be in when the pawls move towards each other. In con-
sequence of the form of the notches and of the pawls being guided and
supported on the are 6 the pawls 9, 10, cannot turn the catch pieces 7, 8,
on their studs 13, and the catch pieces act as though for the time rigidly
fixed to the arc 6. Each pawl engages with that notch of the corre-
sponding catch piece which happens to be level with the edge of the
arc 6, and in consequence of the catch pieces 7, 8, being connected by
the link 14, as herein-before described, it follows that when one piece is
shifted into a position to engage nearer the middle of the are the other
one will engage further from the middle, and the distance betwecu.the
opposite engaging notches will always be the same and equal to the
distance between the pawls 9, 10, when nearest together. Thus these
pawls will always hold the lever 3 steadily and firmly between them
when they approach each other, and they will give a positive motion to the
lever in either direction whenever a change of shuttle has to take place,
for when the back pawl 10 encounters a notch before it reaches the
inner end of its stroke it will turn the lever 3 so as to lower the shuttle
box 2, whilst if the front pawl 9 encounters a notch when moving
inwards it will turn the lever so as to raise the shuttle box, and when-
ever one catch piece is being thus acted upon the other is necessarily
in a position to engage with the other pawl just as that other pawl
completes its inward stroke and thus prevent the lever 3 from being
jerked too far. The catch pieces 7, 8, are shifted by a link 16 jointed to
one of them at one end and at the other to the end of a small lever 17
which in its middle position is in the axial line of the main lever 3.
This lever 17 is carried on a bracket 18 fixed on the outer end of the
stud carrying the main lever 3, and it is formed with three arms, the
one to which the link 16 is jointed, a second 19 fitted with a screw pin
to limit its movement by encountering a stop on the bracket 18, and a
third 20 to which is connected by an adjustable joint a rod 21 that
transmits the movement from the pattern mechanism. The pawls 9, 10,
which act on the main lever 3 are jointed to the vertical arms 22 of two
bell cranks 22, 23, set on studs fixed on the frame a, with horizontal
arms 23 extending towards each other, and these horizontal arms are
actuated together by a cam 11 on the second motion shaft 12, one arm
being fitted with a pin 24 which rests on the cam, whilst the other arm

page_text: is formed with a flange which rests on the pin 24. The pendent and
horizontal arms 22, 23, of each bell-crank lever are in separate pieces,
connected by a strong spring 25 (an arrangement already applied by us
to the lever 26, 27, for actuating the pattern cylinder 28), and it allows
the parts to yield so as to avoid breakage when any accidental obstruc-
tion to the action of the parts occurs. Each spring 25 is arranged
obliquely as regards the arms 22, 23, in consequence of which it allows
of a greater separation of the arms with a given elongation of itself than
it otherwise would, and thereby facilitates and improves its intended
action. The cam 11 for acting on the bell-crank levers 23 may be
constructed to give a maximum shift of two, three, or other number of
shuttles at once irrespective of the total number of shuttles employed,
and it is represented as capable of giving a maximum shift of three
shuttles; or a differential cam may be used, such cam being fitted to
slide along the shaft 12 to bring differently proportioned parts into action
on the levers as may be required. In all cases, whatever may be the
maximum shift the cam 11 can give, any less shift will be given by the
mere action of the pattern mechanism on the catch pieces 7, 8. A
spring 29 is applied to the main lever 3 to counteract the weight of the
shuttle boxes 2, being connected to a pin on a horn 30 formed on the
lever in such a position that the leverage effect of the spring is reduced
as the spring is extended so as to make its action or tension as nearly
uniform as possible. The main lever 3 is prevented from shifting whilst
the pawls 9, 10, are receding from each other for a fresh stroke by a
lever friction brake 31, which is applied to the arc 6 of the lever and
pressed against it by a cam 32, but this cam is shaped so as not to press
the brake at the periods when the lever 3 may be shifted. A pad or
block of wood, leather, or other suitable material is fixed to the brake
lever 31, as indicated by dotted lines, at 33 to bear on the arc 6, and
the lever 31 is made to consist partly of a spring plate 34 (or a spring
may be otherwise applied) so as to compensate for any slight wear of
the pad or block, and thus obviate the necessity of frequent adjustments
by the tenter. The upper end 34 of the brake lever carries an anti-
friction pulley which the cam 32 acts upon. The positions of the
various parts as shown in the Drawing are those at the moment after
the pawls 9, 10, have completed their inward movement, and when the
shuttle is about to be thrown from the box next above the lowest one.
The pattern mechanism consisting of the perforated pattern cylinder 28
and accompanying details is represented as similar to the modification

page_text: described in our earlier Specification herein-before referred to and
numbered 1437 of 1856, but as already stated any other convenient
pattern mechanism may be substituted therefor.
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 and
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 shifting of the shuttle box by means of a lever carrying catch
pieces adjusted by pattern mechanism and acted upon by oppositely
reciprocating pawls, the several parts being combined and arranged
substantially as herein-before described.
2. The making of the levers which actuate the reciprocating pawls or
other equivalent appliances each in two parts connected by a strong
spring to avoid breakage from accidental obstructions, substantially as
herein-before described.
3. The steadying and holding of the main shifting lever (3) by means
of a frictional brake put into action at proper intervals by a cam, sub-
stantially as herein-before described.
In witness whereof, we, the said Matthew Andrew Muir and James
Mollwham, have hereunto set our hands and seals, this Sixth day
of January, in the year of our Lord One thousand eight hundred
and seventy.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
MATTHEW A. MUIR. (L.S.)
JAMES MILWHAM.
(L.S.)