A NEW OR IMPROVED SELF- ACTING DAMPER FOR THE FURNACES OF STEAM BOILERS
Year: 1854

page_text: LETTERS PATENT to John Burgum, of Birmingham, in the County of
Warwick, Engineer, for the Invention of "A NEW OR IMPROVED SELF-
ACTING DAMPER FOR THE FURNACES OF STEAM BOILERS."
Sealed the 9th June 1854, and dated the 1st February 1854
PROVISIONAL SPECIFICATION left by the said John Burgum at the Office
of the Commissioners of Patents, with his Petition, on the 1st February
1854.
I, JOHN BURGUM, of Birmingham, in the County of Warwick, Engineer, do
hereby declare the nature of the said Invention for "A NEW OR IMPROVED
SELF-ACTING DAMPER FOR THE FURNACES OF STEAM BOILERS " to be as follows:-
My Invention consists of a float connected with a damper in the chimney of
the boiler furnace, which said float is acted upon in the following manner :-
The said float is situated in a vertical tube, open at both ends; the lower end
enters a closed box partially filled with water, and dips into the said water; a
pipe conducts steam from the boiler through a valve which may be loaded
with any desired weight, and when the pressure of the steam exceeds the
weight with which the valve is loaded, the said steam raises the said valve, and
passing through it is conducted by another pipe into the top of the before-
mentioned box containing water; the said water is forced by the pressure of
the steam up the vertical pipe in which the float is situated, and raising the
said float shuts the damper. By weighting the valve with different weights it
may be determined that the damper shall be closed at any desired pressure of
steam.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Burgum in the Great Seal Patent Office on the
29th July 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BURGUM, of Birmingham, in the County of Warwick, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of February, in the year of our Lord One
thousand eight hundred and fifty-four, in the seventeenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
John Burgum, Her special licence that I, the said John Burgum, my execu-
tors, administrators, and assigns, or such others as I, the said John Burgum,
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 "A NEW OR IMPROVED SELF-ACTING DAMPER FOR
THE FURNACES OF STEAM BOILERS," upon the condition (amongst others) that I, the
said John Burgum, by an instrument in writing under my 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW. YE, that I, the said John Burgum, 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 (that is to say):-
Figure 1 represents my Invention in elevation, and Figure 2 represents
the same in vertical section. a is a hollow or solid float, suspended on the
chain in the tube or pipe c; the said float a may either be suspended on one
chain, Figure 2, or may be suspended from two chains b, d, Figure 1; e, f,
are counterpoises to the float a; the chains b, d, communicate with dampers
in the chimney or flue of the boiler or furnace. The tube or pipe c, in which
the float a is situated, is open at both ends; the upper end communicates
with the atmosphere, and the lower end communicates through the pipe g with
the box h, which said box is nearly filled with water; a pipe i connected with
the steam boiler conducts steam from the said boiler through a valve k. The
said valve may be loaded to any desired extent by means of the lever 7 and
weight m. When the pressure of the steam exceeds the weight with which

page_text: the valve k is loaded, the said steam raises the said valve, and escapes through
the pipe n.
The said pipe conducts the steam through the bottom to the
upper part of the box h, and the said steam, pressing upon the water in the
said box h, forces the said water up the pipe g into the pipe or tube c, in which
the float a is situated. As the water forced from the box h rises in the tube c,
the float a rises, and, through the chains b, d, closes more or less the damper
or dampers of the steam boiler furnace, and checks the generation of steam.
When the pressure of steam in the boiler diminishes so far that the said steam
is no longer able to raise the valve k, the said valve shuts off the steam.
There being no longer any pressure on the water in the box h, that portion of
the water which had been forced into the tube c descends into the box h, and
the float a, being no longer buoyed up, descends into the position represented
in Figure 2. As the steam is constantly condensing, the quantity of water in
the box h is constantly augmenting. When the water rises above the level of
the pipe n, it passes down the said pipe, and is blown out of the pipe n' by the
current of steam which is allowed to blow off at the said pipe n', or the said
pipe n may terminate with a stop-cock, by which the flow of steam may be
reduced to the minimum quantity. The end of the lever (see Figure 1)
passes through a long loop in the chain d. When the float has risen so high
as to have closed the dampers completely, the pin p, passing through the loop o,
presses upon the lever 1, and closes the valve k. The steam being thus shut off
from the pipe n, is prevented from forcing the whole of the water from the box h
into the tube or pipe c, and afterwards blowing through, and deranging the
apparatus. Any surplus steam accumulating in the boiler after the dampers
are closed must be permitted to escape by a safety valve, my said Invention
having for its object the regulating of the generation of steam by acting on
the dampers, as described, and not being intended as a safety valve. By
adjusting the weight m on the lever / the closing of the dampers may be made
to commence at any desired pressure of the steam. My Invention may either
be placed on or near or at a distance from the steam boiler, as it only requires
to be connected therewith by the pipe i.
Having now described the nature of my said Invention, and the manner of
carrying the same into effect, I wish it to be understood that I do not limit
myself to the precise method herein described, as the same may be varied
without departing from the nature of my said Invention; but I claim as my
Invention, constructing a self-acting damper for the furnaces of steam boilers
by connecting the said damper with a float, the said float being raised, and the
damper closed when the pressure of steam exceeds the pressure to which the

page_text: apparatus is adjusted, the raising of the float being effected by water forced by
the pressure of the steam into the tube containing the said float, as herein
described, and illustrated in the accompanying Drawing.
In witness whereof, I, the. said John Burgum, have hereunto set my
hand and seal, this Twenty-sixth day of July, in the year of our Lord
One thousand eight hundred and fifty-four.
Witness,
GEORGE SHAW.
JOHN BURGUM. (L.S.)