IMPROVEMENTS IN LOOMS FOR WEAVING
Year: 1862

page_text: PROVISIONAL SPECIFICATION left by David Crichton, William Don-
.bavand, and Duncan Crichton at the Office of the Commissioners of
Patents, with their Petition, on the 11th June 1862.
We, DAVID CRICHTON, Machinist, WILLIAM DONBAVAND, Scale Beam and
Weighing Machine Manufacturer, and DUNCAN CRICHTON, Engineer, all of
the City of Manchester, in the County of Lancaster, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN LOOMS FOR WEAVING,"
to be as follows:-
Our Invention consists of improvements on and in Crichton and Cathcart's
Invention. for which Letters Patent were granted, dated the 17th day of
September 1856, No. 2174, which consisted in an improved, arrangement of
machinery or apparatus for producing intermittent rotary motions of different
velocities from a series of advancing and receding intermittent motions
working alternate motions intermittently. Our present Invention consists of
an improved arrangement of machinery or apparatus for producing the same
effects. The nature of our said Invention will be understood by reference, to
the Figures and letters on the accompanying Sheet of Drawings, in which Fig. 1
is a transverse section, and Fig. 2. a front elevation of part of a loom, having
our improvements attached, shewing their application to the cloth beam of a
loom. To one of the sword arms a is jointed the ratchet wheel propeller b,
which works the ratchet wheel c and the cam d, both being fixed together.
The cam d is in contact with the bowl or stationary block e, on one end of a
double right-angled lever f, g, h. The said lever works on the stud i fixed to
the framework, and has on the arm ga weight k to keep the block or bowl'
against the periphery of the cam. The top of the arm his jointed to one end

page_text: of the link 1, the other end of which is connected to the pin m fixed to the
lever n, and passing through the slot of the slotted lever o working loose on
the shaft p, which turns in the bracket q fixed to the framework. The top of
the lever n is jointed to a projecting end r of the lever s, which carries at one
end a roller or rod t in contact with the cloth beam u, and at the other end is
the weight v.
The said levers works on a stud fixed to the framework, and
as the cloth upon the beam increases in diameter the roller or rod descends
and causes the pin to descend in the slot of the slotted lever. On the shaft p
there is. a second lever, w working loose upon it, and fixed to it there are two
ratchet wheels x, y, having different numbers of teeth, and also at its extreme
end the pinion z communicates by the train of wheels with the cloth beam u.
To the tops of the levers v, w, are jointed ratchet wheel propellers 6', c',
working in the teeth of the ratchet wheels x, y. To the lever o is jointed one
end of the link d', and to the lever w one end of the link e', the other ends of
both links being jointed to the lever f³, so that when the lever o and its pro-
peller vibrates in one direction, the lever w and its propeller vibrates in an
opposite direction, both movements taking place at the same time. When
the loom is put in motion, the forward action of the propeller b will give
motion to the ratchet wheel c and cam d, which, acting on the arm f, gives an
advancing and receding intermittent motion to the arm h, and by means of the
links l, d', and e¹, an alternate vibrating motion to the levers o, w, which will
communicate, by means of the propellers b', c', rotary motion to the ratchet
wheels x, y, and then to the cloth beam by the action of the pinion z on the
pair of wheels, as seen in the Drawings. At the commencement of weaving a
piece of cloth, the pin m fixed to the lever is at its' highest position in the
slot of the lever o, and therefore gives the greatest amount of motion to the
levers o and w and propellers b', c¹, and consequently to the ratchet wheels,
gearing, and cloth beam. As the cloth beam increases in diameter in the
process of weaving, the roller or rod t will descend and lower the lever n and
pin m in the slot of the slotted lever o, and 'thus the alternate motions. of the
levers o, w, and their propellers will be constantly decreasing in length, and
produce in the same ratio a constantly decreasing speed in the ratchet wheels
x, y, which is communicated to the cloth beam of the loom by the train of
wheels as shewn in the Drawings.