IMPROVEMENTS IN CAPSTANS
Year: 1868

page_text: LETTERS PATENT to William Clarke, of Gateshead, in the County of
Durham, and Edmund Walker, of Poplar, in the County of Mid-
dlesex for the Invention of "IMPROVEMENTS IN CAPSTANS."
Sealed the 18th September 1868, and dated the 18th March 1868.'
PROVISIONAL SPECIFICATION left by the said William Clarke and
Edmund Walker at the Office of the Commissioners of Patents,
with their Petition, on the 18th March 1868.
We, WILLIAM CLARKE, of Gateshead, in the County of Durham, and
EDMUND WALKER, of Poplar, in the County of Middlesex, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN CAPSTANS,"
to be as follows:--
Our Invention consists in constructing captans as follows:-On the
main shaft a pinion is keyed; this pinion gears into one or more
other pinions, which run loosely on spindles fixed in the béd plate;
these pinions gear into an internally toothed wheel, which runs loosely
on the main shaft. An ordinary capstan body with a chain lifter at the
bottom can be attached to this wheel by pins or bars inserted through
the bottom of the lifter into the wheel whereby great power is obtained.

page_text: When speed is required these pins are taken out and are inserted
through the capstan head into the body.
The main features of our Invention are the internally toothed wheel
<detached from the capstan body and running loosely on the main shaft;
also the means of attaching it to the capstan body when required.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Clarke and Edmund Walker in the Great
Seal Patent Office on the 18th September 1868.
"TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
CLARKE, of Gateshead, in the County of Durham, and EDMUND WALKER,
of Poplar, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of March, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said William Clarke and Edmund Walker,
Her special licence that we, the said William Clarke and Edmund
Walker, our executors, administrators, and assigns, or such, others as
we, the said William Clarke and Edmund Walker, 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 CAPSTANS," upon the condition (amongst others) that we, the said
William Clarke and Edmund Walker, or one of us, our executors or
administrators, by an instrument in writing under our, or one of
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 William Clarke and Edmund
Walker, do hereby declare the nature of our said Invention, and in

page_text: what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement thereof, reference
being had to the Drawings hereunto annexed, that is to say:-
Our Invention consists in constructing capstans as follows:-On the
main shaft a pinion is keyed; this pinion gears into one or more other
pinions, which run loosely on spindles fixed in the bed plate; these
pinions gear into an internally toothed wheel, which runs loosely on
the main shaft. An ordinary capstan body with a chain lifter at the
bottom can be attached to this wheel by pins or bars inserted through
the bottom of the lifter into the wheel, whereby great power is
obtained. When speed is required these pins are taken out and are
inserted through the capstan head into the body.
The accompanying Drawing is a vertical section of a capstan
constructed according to our Invention. A is the main shaft; B, the
capstan head; and C, the capstan body. The shaft A passes through
the bed plate G, which is fixed. D is a pinion, keyed on the shaft A,
and gearing into other pinions E, which run loosely on spindles H
fixed in the bed plate G. The pinions E gear into an internally
toothed wheel F, which turns loosely on the shaft A. I is a chain
lifter attached to the capstan body C. When great power is required
pins or bars a, a, are passed through the bottom of the lifter I into
the wheel F, as shewn, so that the rotation given to the capstan
head is transmitted to the capstan body through the intermediation of
the pinions D and E and the wheel F. When speed is required the
pins or bars a, a, are removed from the lifter, and inserted through
the capstan head into the body, as seen in dotted lines at b, b, so
that the rotation of the head is transmitted to the body direct.
And having now described the nature of our said Invention, and in
what manner the same is to be performed, we declare that we claim
as our improvements in capstans,-
First. The construction of capstans with an internally toothed
wheel F detached from the capstan body, and running loosely on the
main shaft, substantially as and for the purpose herein-before described
and represented in the accompanying Drawing.
Second. The means substantially as herein-before described of
attaching the said internally toothed wheel to the capstan body
when required.

page_text: Third. The general combination or arrangement of parts of capstans
herein-before described and represented in the accompanying Drawing.
In witness whereof, I, the said Edmund Walker, for myself and
on behalf of the said William Clarke, have hereunto set my
hand and seal, this Seventeenth day of September, One thousand
eight hundred and sixty-eight.