IMPROVEMENTS IN MARINE STEAM ENGINES
Year: 1865

page_text: LETTERS PATENT to John Dean, of Prospect Place, Bolton Street, Hands-
worth, near Birmingham, for the Invention of "IMPROVEMENTS IN MARINE
STEAM ENGINES."
Sealed the 28th April 1865, and dated the 8th March 1865.
COMPLETE SPECIFICATION filed by the said John Dean at the Office of
the Commissioners of Patents, with his Petition and Declaration, on the
8th March 1865, pursuant to the 9th Section of the Patent Law Amend-
ment Act, 1852.
TO ALL TO WHOM
THESE PRESENTS SHALL COME, JOHN
DEAN, of Prospect Place, Bolton Street, Handsworth, near Birmingham, send
greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN
MARINE STEAM ENGINES," 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 Declaration that I am the first and true Inventor
thereof.
NOW KNOW YE, that I, the said John Dean, do hereby declare that the
following Complete Specification under my hand and seal fully describes and

page_text: ascertains the nature of the said Invention, and in what manner the same
is to be performed, in and by the following statement :---
It frequently occurs in rough weather, when the vessel is pitching, that that
the paddles or screws are entirely out of the water, and when this takes place
the engines are liable to "race," or acquire an increased velocity, whereby
a considerable waste of steam takes place, besides serious and not unfre-
quently dangerous strains or breakages of the machinery occurs. In
order to remedy this evil, and to provide for a steady and uniform
working of the engines proportioned to the resistance to be overcome, I pro-
pose to fix a tube or cylinder on each side of the vessel for each engine and
paddle wheel, or at the stern, as may be necessary for the screw in steam
vessels. In this tube or cylinder an air ball or float of metal or other material
is to be placed. Through this tube or cylinder is passed a vertical rod or shaft
with guides; this shaft will act upon the throttle valve or equilibrium valve, as
the case may be, by means of rods and levers and gab handle, to attach to the
ordinary throttle valve handle.
The principle of my Invention consists in this:-When the paddle wheels
or screws are raised out of the water the air ball or float before described will
fall, and the levers and rod attached to and acting upon the valve will shut
the steam off in proportion to the depth of the paddles, and, on the other hand,
when the paddles are fully immersed, the air ball and levers are raised into
such a position as to allow the full quantity of steam to enter the cylinders.
The air float, vertical rod, and levers being acted upon directly by the water,
it will at once be apparent that the quantity of steam required will under
the circumstances be exactly equal to the power required and the resistance
to be overcome. The tube or cylinder may be placed inside or outside the
vessel vertically, or in any other more advantageous position, and the float
may be spherical, square, or oblong to suit outside adaptation, if position
inside will not admit, always acted upon directly and regulated by the greater
or lesser depth of water on the paddle wheels or screws.. In the case of paddle
wheel engines, there being an independent air float and shaft to each engine,
the action is equalised under all circumstances, that is to say, when the paddle
wheel on one side is immersed and the other out of the water, the. throttle
valve of the former shall be open to admit the full amount of steam required
and the throttle valve of the latter be nearly closed, only admitting a small
amount of steam to keep the engine in motion, so that the former has not to
drive the latter, which would be the case were the steam shut off close, by
which means the entire strain and power is effectually balanced throughout..

page_text: DESCRIPTION OF THE DRAWINGS.
A reference to the accompanying sketch will fully illustrate the principle of
the Invention, and the mode of its application.
Figure No. I represents the cross section of a steam vessel with paddles,
and the parts marked A, B, C, D, E, F, G, form part of the Invention.
A is the tube or cylinder, open at the bottom for the admission of the water,
within which it will stand at the same level as outside. B is an air ball or float
fixed to a vertical shaft, which it elevates or depresses according as the water
in the tube or cylinder may elevate or depress the ball or float. C, D, E, are
shafts through which the motion conveyed by the ball and shaft B is trans-
mitted to the valve G placed in the steam pipe F. When the paddles are
most immersed the ball B is at its greatest height, and the levers C, D, E,
acting upon the valve G opens it to its fullest extent, consequently the greatest
amount of steam is admitted to the cylinder just when it is required. Again,
when the paddles are out of the water the ball B is at the bottom of the
chamber A, and the action of the ball upon the levers C, D, E, will close the
valve G, so that the least amount of steam is admitted when least required.
This action does not only take place when the ball B is at either extremity of
the chamber A, but is continuous and in proportion to the position of the
ball, consequently the admission and power of steam is always in proportion
to the work to be done, which is of course regulated by the immersion of the
paddles. The chambers A, A, would be placed in advance of the paddles and
screws, so that the water within them would not be agitated by the action of
either, and moreover the steam would be admitted, and be ready to do its
work just as the sea or wave came against the paddle or screw.
Figure No. 2 shews the same principle adapted for a screw vessel.
Figure No. 3 illustrates how the action may be suspended when the vessel
is in comparatively smooth water, and its action considered unnecessary. The
parts A, B, C, D, E, F, G, are levers and shafts, as before described, for the
transmission of motion to the valve. The lever F is attached to G by a gab or
other fastening, and it is only necessary to disconnect F and G to suspend the
action of the apparatus.
TAHNT
זינד?
JOHN DEAN.
D.)