The. APPLICATION OF A DOUBLE-ACTING MOVING BLADE TO COTTON GINS
Year: 1871

page_text: LETTERS PATENT to James Greaves, Senior Partner in the Firm of
Greaves, Cotton, and Company, of Bombay and Broach, in the East
Indies, and also Principal Partner in the Firm of James Greaves
and Company, Stockport, Cheshire, for the Invention of "The.
APPLICATION OF A DOUBLE-ACTING MOVING BLADE TO COTTON GINS."-A com-
munication from abroad by George Cotton, a Partner in the Firm of
Greaves, Cotton, and Company, Bombay and Broach, in the East
Indies.
5
COMPLETE SPECIFICATION filed by the said James Greaves at the
Office of the Commissioners of Patents, with his Petition and
Declaration, on the 30th. December 1871, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
GREAVES, Senior Partner in the Firm of Greaves, Cotton, and Company,
of Bombay and Broach, in the East Indies, and also Principal Partner in

page_text: the Firm of James Greaves and Company, of Stockport, Cheshire, send
greeting.
WHEREAS I am in possession of an Invention for "THE APPLICATION OF
A DOUBLE-ACTING MOVING BLADE TO COTTON GINS," and have petitioned Her
Majesty to grant unto me, my executors, administrators, and assigns,
Her Royal Letters Patent for the same, and have made solemn Decla-
ration that the same has been communícated to me from abroad by
George Cotton, a Partner in the Firm of Greaves, Cotton, and Company,
Bombay and Broach, in the East Indies.
NOW KNOW YE, that I, the said James Greaves, do hereby declare
that the following Complete Specification, under my hand and scal, fully
describes and ascertains the nature of the said Invention, and in what
manner the same is to be performed, in and by the following statement,
that is to say :-
Macarthy gins when first introduced to notice were distinguished by
performing two distinct classes of actions by two distinct sets of instru-
ments. By the first class the fibres were drawn from the seeds and
delivered; by the second the seeds were loosened from the fibres pre-
paratory thereto. The instruments by which the first was performed
were two; a leather covered roller and a fixed blade pressing thereon, by
the friction resulting from which pressure the fibres as far as possible
were pulled off the seeds and delivered. The latter act was effected by
an oscillating or reciprocating doffing knife or blade which struck the
seeds at each reciprocation, shook them, and so loosened their adhesion
to the fibres, and rendered the detaching of them from each other by the
roller and fixed knife or blade more casily effected. Two doffing knives
were subsequently applied to improve this last operation with con-
siderable effect.
George Cotton of the firm in India, in which I am partner with him,
has communicated to me the present Invention by which one blade
is made more efficient than two had been before, both because one blade
acted upon by one crank on one crank shaft is simpler and lighter to
drive than the duplex action required by two, but especially because one
blade can be more closely set and adjusted to the leather roller and fixed
blade than any two moving blades could possibly be, and hence will
perform better work in clearing cotton of adhering seeds.
And in order that the Invention communicated to me from India by

page_text: my said partner George Cotton may be more fully understood and more
readily carried into effect, I will now proceed to describe the same,
reference being had to the accompanying Drawings, in which Fig. 1 is a
sectional elevation of so much of a cotton gin as shows the improve-
ments communicated to me; Fig. 2 shows a corresponding view of the
same parts, Fig. 1, with the blade at the upper extremity, and Fig. 2
with the blade at the lower extremity of the stroke.
Fig. 3 represents a front and end sectional elevation of a blade or
knife of a single-acting gin altered to double-action in accordance with
the present Invention; Fig. 4 shows the same blade as made for a new
machine.
In Fig. 1 a represents a section of the leather covered roller; b, a
section of the fixed blade; c is a section of the cast-iron plate against
which the blade or knife b is fixed by the bolts and washers d; e is the
moving blade (in section); e¹ is the upper rib thereof; e², the corre-
sponding lower rib; e³, the space between the two ribs through which
the loosened cotton is drawn by the friction of the leather roller and
fixed knife. The upper edge of the lower rib of the moving blade and
the lower edge of the upper rib of the same (see Figs. 1 and 2) during
any given reciprocation give the cotton seed a double shake, and thereby
loosen the attachment between seed and fibre, and the latter is drawn
through the slotted space e³ by the friction aforesaid of the leather roller
and fixed knife, and delivered by the rotation of the former, to which it
adheres sufficiently for this purpose. On Fig. 3 is shown the form of
blade for an altered gin, the upper rib e¹ in which is fastened to the
lower rib e² by the cross plates f by means of rivets or otherwise. The
plates being made of such length as to separate the upper and lower
rib so far from each other as to leave the space e³ through which the
fibre is drawn by the friction of the roller a. An inspection of the
Drawing will show that at each oscillation the upper edge of the lower
rib and the lower edge of the upper rib each give the seed a distinct
shake (sec especially Figs. 1 and 2, where this is plainly brought out).
By this double shake the attachment of the seed to the fibre is loosened
and the latter are more easily detached from the former thereby.
Having now described the nature of the Invention communicated to
me by the said George Cotton resident in India, I, James Greaves,
hereby declare that there is secured to me thereby the double per-
formance of the doffing knife or moving blade of a cotton gin by which

page_text: the fibres are more thoroughly separated from the seed than is possible
by either one or two doffing knives as heretofore practised, and the
method of constructing the same as shown and described.
In witness whereof, I, the said James Greaves, have hereunto set
my hand and seal, this Twenty-second day of December 1871.