IMPROVEMENTS IN CAPSTANS
Year: 1868

page_text: LETTERS PATENT to William Thomas Carrington, of No. 10, Park
Street, Westminster, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN CAPSTANS."
Sealed the 2nd March 1869, and dated the 7th September 1808.
PROVISIONAL SPECIFICATION left by the said William Thomas
Carrington at the Office of the Commissioners of Patents, with his
Petition, on the 7th September 1868.
I, WILLIAM THOMAS CARRINGTON, of No. 10, Park Street, West-
minster, in the County of Middlesex, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN CAPSTANS," to be as follows:-
My Invention has for its object an improved construction of capstans,
whereby the surging or shifting of the rope or chain as it is wound upon
the barrel, such as must necessarily occur with the present mode of
constructing capstans, is entirely prevented.
For this purpose I form upon the barrel of the capstan a series of two
or more circular grooves, and I combine with the capstan an auxilliary
barrel, drum, or pulley placed a short distance from the capstan, and
having one or more circular grooves corresponding with those on the

page_text: barrel, so that the rope or chain to be hauled in by the capstan is first
led over the first groove of the same, whence it passes over the first
groove of the auxilliary barrel or drum to the second groove of the
capstan, and so on, the slack end being drawn off in the ordinary
manner. From this it will be seen that the rope or chain will always
pass on to one and the same groove of the capstan, and that consequently
no surging or shifting will take place. If requisite the auxilliary barrel
or drum may be geared with the capstan in such a manner as to be made
to revolve in the same direction with it in order to obtain a greater hold
rope with a less number of grooves. In some cases where no very
great purchase is required I form only one single deep V groove of large
diameter upon the barrel of the capstan, so that the rope in being passed
nearly round the groove (the slack being then drawn off) will be held
with sufficient force in such groove to prevent slipping. Should the rope
be drawn so tightly into the groove as not readily to deliver from the
same at the slack end a fixed wedge may be held in such a position in
the groove as to plough out the rope at the point where it is to deliver.
If requisite a break or pressure roller can be applied to the rope at any
part of the circumference of the groove to prevent the rope from slipping
too quickly when slacking out. My improved construction of capstans
may be worked by manual, steam, or other motive power, and they may
be employed for docks, ships, wharves, and for any other purposes to
which ordinary capstans are applied.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Thomas Carrington in the Great Seal
Patent Office on the 6th March 1869.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
THOMAS CARRINGTON, of No. 10, Park Street, Westminster, in the
County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of September, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said William Thomas Carrington, Her
special licence that I, the said William Thomas Carrington, my exc-

page_text: cutors, administrators, and assigns, or such others as I, the said William
Thomas Carrington, 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 William Thomas Carrington, 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 Scal Patent
Office within six calendar months next and immediately after the date
of the said Letters Patent.
NOW KNOW YE, that I, the said William Thomas Carrington, do
hereby declare the nature of the said Invention, and in 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
accompanying Sheets of Drawings, and to the figures and letters marked
thereon, that is to say :-
My Invention has for its object an improved construction of capstan,
whereby the surging or shifting of the rope or chain as it is wound upon
the barrel, such as must necessarily occur with the present mode of
constructing capstans, is entirely prevented.
For this purpose I form upon the barrel of the capstan a series of two
or more circular grooves, and I combine with the capstan an auxilliary
barrel, drum, or pulley placed a short distance from the capstan, and
having one or more circular grooves corresponding with those on the
barrel, so that the rope or chain to be hauled in by the capstan is first
led over the first groove of the same, whence it passes over the first
groove of the auxilliary barrel or drum to the second groove of the
capstan, and so on, the slack end being drawn off in the ordinary
manner. From this it will be seen that the rope or chain will always
pass on to one and the same groove of the capstan or auxilliary barre!,
and that consequently no surging or shifting will take place. If requisite
the auxilliary barrel or drum may be geared with the capstan in such a
manner as to be made to revolve in the same direction with it in order
to obtain a greater hold on the rope with a less number of grooves. In

page_text: some cases where no very great purchase is required I form only.one
single deep V groove of large diameter upon the barrel of the capstan, so
that the rope in being passed nearly round the groove (the slack being
then drawn off) will be held with sufficient force in such groove to
prevent slipping. Should the rope be drawn so tightly into the groove
as not readily to deliver from the same at the slack end a fixed wedge
or a roller may be held in such a position in the groove as to plough out
the rope at the point where it is to deliver. If requisite a break or
pressure roller can be applied to the rope at any part of the circum-
ference of the groove to prevent the rope from slipping too quickly when
slacking out. My improved construction of capstans may be worked by
manual, steam, or other motive power, and they may be employed for
docks, ships, wharves, and for any other purposes to which ordinary
capstans are applied.
Having thus set forth the nature of my Invention I will now proceed
more particularly to describe some of the arrangements by which it may
be carried into effect.
Figures 1 to 3 on Sheet I. of the accompanying Drawings show one
arrangement of my improved capstan. Figure 1 shows a side elevation
of the same partly in section; Figure 2 shows an end elevation; and
Figure 3 shows a plan. Similar letters of reference indicate similar parts
in each of the Figures.
The capstan A is provided with a number of circular grooves a¹, a³, a³,
a', as, and in close proximity to it is placed an auxilliary barrel or drum B
having a series of similar grooves b', b², ³, b', situated in intermediate
positions relative to the grooves of the capstan. The barrel B is carried
by a vertical shaft C running in bearings in the bed plate D and in the
step E in a similar manner to the capstan itself; it has rotary motion
imparted to it in the same direction and at the same speed as that of the
capstan by means of a spur wheel F on the shaft G of the latter in gear
with an intermediate wheel H on the shaft I which is in gear with a
wheel J on the shaft C. From the above described arrangement it will
be seen that the rope or chain to be hauled in will be passed first partly
round the groove a' of the capstan, thence round the groove 6¹ of the barrel
and on to the groove a³ of the capstan, and so on, over as many grooves
as may be required to afford the requisite purchase, the loose end being
hauled away by hand from the last such groove in the usual manner; or
in place of leading the rope or chain first on to the capstan it will be

page_text: evident that it may be first led on to the groove of the barrel B. In
place of arranging the grooves of the barrel B horizontal and inter-
mediate between the grooves of the capstan, as shown, the axis of the
barrel may be slightly inclined, so that each groove thereof shall on the
one side be level with the one groove of the capstan, while on the other
side it shall be level with the next groove above. The capstan may be
worked either by means of capstan bars in the usual manner, or it may
be driven by the shaft K receiving motion from a steam engine or other
suitable source of motive power; the bevil pinion L on which shaft is
for this purpose in gear with the bevil wheel M on the intermediate
shaft I. The putting in and out of gear of the capstan with the engine
may be conveniently effected by means of the treadle N actuating a
clutch apparatus in any well-known manner.
Figures 4 and 5 on Sheet II. of the Drawings show respectively an
elevation and a plan of another arrangement of my improved capstan in
which in place of a number of grooves being formed on the capstan A,
as in the previous arrangement, it is provided with one single deep
V groove a, so that the rope to be hauled in being passed round such
groove will be sufficiently gripped thereby to prevent slipping. The
angle of the groove may be varied from that shown on the Drawing
according to the size and nature of the rope employed. At the point
where the loose end of the rope is drawn off a roller B is provided cither
for keeping the rope well in the groove up to that point or for leading it
out of the groove, according as the rope from its size would be liable
either to slip or to stick in the groove. The position of this roller may
be varied according to circumstances by shifting it to the one or other of
the sockets b', ', into which the pin b of the roller fits. In place of the
roller B a wedge or plough may be fitted on the pin b which passing
into the V groove a will plough out the rope if required. The other
parts of the capstan are constructed in the usual manner, and therefore
require no further description.
Having thus described the nature of my Invention, and in what
manner the same is to be performed, I wish it to be understood that I
am aware that two multiple grooved barrels or pulleys have before been
employed for hauling ropes or chains, and I therefore in no way claim
their application generally; but what I claim is,-
First. Constructing capstans with two or more annular grooves acting
in combination with one or more other annular grooves on an auxilliary

page_text: barrel, drum, or pulley, either geared or not with the capstan, substantially
in manner and for the purposes set forth.
Second. Constructing capstans with a single V groove acting either
with or without a brake or pressing roller, or with or without a plough
or roller to lead the tail of the rope out, substantially in manner and for
the purposes set forth.
In witness whereof, I, the said William Thomas Carrington, have
hereunto set my hand and seal, this Fifth day of March, in the
year of our Lord One thousand eight hundred and sixty-nine.