IMPROVEMENTS. IN CAPSTANS
Year: 1865

page_text: LETTERS PATENT to William Dakin Grimshaw, of Birmingham, in the
County of Warwick, Engineer, for the. Invention of "IMPROVEMENTS.
IN CAPSTANS."
Sealed the 3rd April 1866, and dated the 6th October 1865.
PROVISIONAL SPECIFICATION left by the said William Dakin Grimshaw
at the Office of the Commissioners of Patents, with his Petition, on the
6th October 1865.
I; WILLIAM DAKIN GRIMSHAW, of Birmingham, in the County of Warwick,
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN CAPSTANS," to be as follows, that is to say :-
My Invention consists in forming a capstan with a bevil wheel fixed
within the under side of the barrel, which bevil wheel is driven by bevilled
pinions hung in brackets cast upon the bed plate. The spindles upon which
these bevil pinions are hung pass through the vertical flange of the bed plate,
and carry each a ratchet and pawl fixed in the ends of the sockets which
receive the levers for working the capstan. A mast comes through the barrel,
and is continued downwards through one deck or more, according to the rate
of the ship. Any number of pairs of levers may be employed, and by reversing

page_text: the pawls the motion of the barrel is reversed also. When the pawls are
lodged centrally the capstan works as an ordinary capstan by means of levers
in the cap.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Dakin Grimshaw in the Great Seal Patent Office
on the 6th April 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
DAKIN GRIMSHAW, of Birmingham, in the County of Warwick, Engineer, send
greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of October, One thousand eight hundred
and sixty-five, in the twenty-ninth year of Her reign, did, for Herself,
Her heirs and successors, give and grant unto me, the said William Dakin
Grimshaw, Her special license that I, the said William Dakin Grimshaw, my
executors, administrators, and assigns, or such others as "I, the said Williani
Dakin Grimshaw, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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
Dakin Grimshaw, by an instrument in writing under ny hand and seal
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 William Dakin Grimshaw, do hereby
declare the nature of my said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the fol-
lowing statement, reference being had to the Drawings hereunto annexed,
and to the letters and figures marked thereon, that is to say:-
In capstans of the ordinary construction it has been usual to employ pawls
on the capstan, taking a circular ratchet or pawl bed.
My Invention has for its object dispensing with the pawl bed and pawls,
and making use of the lever or bandspike sockets as pawls when the capstan
is rotated by levers or bandspikes set in the head of the capstan ; and it con-

page_text: Figure 1 is a vertical section of the capstan through the actuating shafts or
mast, and Figure 2 is a section through one of the lever or handspike sockets.
Similar marks of reference denote the same parts.
In the Drawing (a) is the base of the capstan carrying and supporting the
shaft or mast (b), upon which is the capstan barrel (c) retained by the nut (d)
on the end of (b); (e) are the sockets in the head of the capstan for receiving
the lever or handspikes when the capstan is to be moved by power applied
directly to the said capstan; (f.f.) are short shafts or spindles supported in
the base (a) with a bearing or journal box on each side of the pinions (g, g)
that gear into the wheel (h) on the under side of the capstan barrel (c); (ii)
are ratchet wheels secured to the shafts (f, f) outside the bed (a), and each
ratchet wheel is between the forks of the lever or handspike sockets (k) on the
shafts (f) respectively; (7) is a double-acting spring pawl, having its fulcrum
in the socket (k) and fitted to take the teeth of (i), as seen in Figure 2, so
that the ratchet can be made to operate either way. Both of the sockets (k)
are fitted in the same manner, and it will be evident that when the lever or
bandspike sockets are thrown over upon the deck, the pawls of the said sockets
will act as ratchets to prevent the capstan running back while the said capstan
is being worked by levers or handspikes in the sockets (e), and when it is
desired to move the capstan with a slower speed and increased power the levers
or handspikes are to be inserted in the sockets (k), and the said sockets and
handspikes worked simultaneously, the one moving the capstan as the ratchet
on the other runs back over the teeth.
Having thus described the nature of the said Invention, and in what manner
the same is to be performed, I claim, without limiting myself to these precise
details, the sockets (k) and spring pawls (1), in combination with the gearing

page_text: wheels (and h.), and the capstan (c), substantially as described, whereby.a
separate pawl bed and pawls are dispensed with, as herein more fully set forth
and specified.
In witness whereof, I; the said William Dakin Grimshaw have here*
unto set my hand and seal, this Fourth day of April, in the year of our
Lord One thousand eight hundred and sixty-six.
WILLIAM DAKIN GRIMSHAW. (L.B.)