IMPROVEMENTS IN CAPSTANS
Year: 1857

page_text: LETTERS PATENT to Thomas Brown, of Fenchurch Street, in the City of
London, for the Invention of "IMPROVEMENTS IN CAPSTANS."
Sealed the 24th July 1857, and dated the 4th March 1857.
PROVISIONAL SPECIFICATION left by the said Thomas Brown at the
Office of the Commissioners of Patents, with his Petition, on the
4th March 1857.
I, THOMAS BROWN, of Fenchurch Streat, in the City of London, do hereby
declare the nature of the Invention for "IMPROVEMENTS IN CAPSTANS," to be as
follows:-
This Invention has for its object improvements in capstans. For these
purposes a central plate is applied below the body of a capstan and within
the pawl rim. The lower part of the capstan body is made with a ring of
internal teeth. The central plate carries the axes of pinions, the teeth of
which take into the ring of teeth at the lower part of the body of the capstan.
The central plate is made with indents or recesses in its periphery to receive
the end of a bolt when it is desired to fix the central plate to the pawl plate,
and at the same time to cause the barrel of the capstan to be revolved by a
toothed wheel, which is fixed on the axis of the capstan, the teeth of which
take into the teeth of the pinions carried by the axes on the central plate.
The head of the capstan is fixed to the axis, and the barrel may at any time
be fixed to the head by suitable bolts when it is, desired that the barrel of the
capstan should be revolved by the capstan bars, at which time the bolt to the
central plate is withdrawn.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Brown in the Great Seal Patent Office on the
1st September 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
BROWN, of Fenchurch Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fourth day of March, in the year of our Lord One
thousand eight hundred and fifty-seven, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said Thomas Brown, Her special-licence-that-I, the said Thomas Brown, my
executors, administrators, and assigns, or such others as I, the said Thomas
Brown, my 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 I, the said Thomas Brown, my
executors or administrators, by an instrument in writing under my, 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 I, the said Thomas Brown, do hereby declare the
nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say-
...
This Invention has for its object improvements in capstans. For these
purposes a central plate is applied below the body of a capstan and within
the pawl rim. The lower part of the capstan body is made with a ring of
internal teeth. The central plate carries the axes of pinions, the teeth of
which take into the ring of teeth at the lower part of the body of the capstan.
The central plate is made with indents or recesses in its periphery to receive
the end of a bolt when it is desired to fix the central plate to the pawl plate,
and at the same time to cause the barrel of the capstan to be revolved by a
toothed wheel, which is fixed on the axis of the capstan, the teeth of which
take into the teeth of the pinions carried by the axes on the central plate.
The head of the capstan is fixed to the axis, and -the barrel may at any time

page_text: be fixed to the head by suitable bolts when it is desired that the barrel of the
capstan should be revolved by the capstan bars, at which time the bolt to the
central plate is withdrawn.
Having thus stated the nature of my said Invention, I will proceed more
fully to describe the manner of performing the same :-
DESCRIPTION OF THE DRAWING.
Figure 1 shows a vertical section of a capstan constructed according to my
Invention; Figure 2 is a plan thereof. In each of these Figures the same
letters are used to indicate the same parts. a is the capstan head, which is
keyed or fixed to the axis c. The head is made fast to the barrel b of the
capstan when desired by means of bolts d, d. The lower part of the body of
the capstan is formed with an internal ring of teeth e, e, into which the teeth
of three pinions f. f, gear, and such pinions also gear into the teeth of the
cog wheel g fixed on the axis c of the capstan. h is a central plate, which is
carried by a projecting fixed ring i, which enters a groove formed on the
under side of the central plate h. The central plate is formed with or has
fixed to it the axes h', h', of the three pinions f, f. The central plate h is
made with recesses h2, h3, at its periphery, into which the end of the sliding
bolt j fits, and it is fixed or held by the bolt passing through it, as is shewn.
From the above description it will be understood that when the bolts d, d, are
removed and the bolt j is inserted, so as to fix the central plate h, the effect
of rotating the capstan head will be to increase the power of the barrel b of
the capstan, but at the same time to decrease its speed.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I make no claim to
the mechanical parts separately; but what I claim is the application of the
central plate h in combination with the pinions f, f, as herein described.
In witness whereof, I, the said Thomas Brown, have hereunto set my
hand and seal, this Twenty-ninth day of August, in the year of our
Lord One thousand eight hundred and fifty-seven.
Witness,
JNO. ALCOCK.
THOMAS BROWN. (L.S.)