A NEW OR IMPROVED METHOD OF AND APPARATUS FOR PREVENTING THE EXPLOSION OF OR INJURY TO STEAM BOILERS THROUGH DEFICIENCY OF WATER
Year: 1858

page_text: LETTERS PATENT to Edwin Thomas Wright, of Wolverhampton, in the
County of Stafford, Engineer, for the Invention of "A NEW OR IMPROVED
METHOD OF AND APPARATUS FOR PREVENTING THE EXPLOSION OF OR INJURY TO
STEAM BOILERS THROUGH DEFICIENCY OF WATER."
Sealed the 3rd December 1858, and dated the 24th September 1858.
PROVISIONAL SPECIFICATION left by the said Edwin Thomas Wright
at the Office of the Commissioners of Patents, with his Petition,
on the 24th September 1858.
I, EDWIN THOMAS WRIGHT, of Wolverhampton, in the County of Stafford,
Engineer, do hereby declare the nature of the said Invention for "A NEW OR
IMPROVED METHOD OF AND APPARATUS FOR PREVENTING THE EXPLOSION OF OR INJURY
TO STEAM BOILERS THROUGH DEFICIENCY OF WATER," to be as follows:-
My said Invention consists in connecting a water buoy or float in the steam
boiler with the door of the furnace, as herein-after explained, so that when the
water falls below a given level in the boiler, the said furnace door is opened,
and by this means cold air is admitted into the furnace, the overheating or
explosion of the boiler is prevented, and the attendant on proceeding to fire is
warned of the state of the water by the open door.

page_text: In carrying my said Invention into effect I employ any ordinary float in the
boiler, and connect it, by means of a chain and pulley, or by levers, or other-
wise, with the furnace door, so that when the float descends by the sinking
of the water in the boiler below the proper level, the furnace door is opened
and cold air admitted.
Instead of connecting the float to the ordinary furnace door, I sometimes
attach it to a separate air door, but I prefer generally to connect the float to
the fire door, because the apparatus is thus put in motion, and its perfect
condition ascertained whenever the door is opened for firing.
I sometimes also connect a whistle, bell, or other alarum with the apparatus
described, so that attention is immediately called to the opening of the door.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edwin Thomas Wright in the Great Seal Patent Office
on the 22nd March 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWIN
THOMAS WRIGHT, of Wolverhampton, in the County of Stafford, Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fourth day of September, in the year of our
Lord One thousand eight hundred and fifty-eight, in the twenty-second year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Edwin Thomas Wright, Her special licence that I, the said
Edwin Thomas Wright, my executors, administrators, and assigns, or such
others as I, the said Edwin Thomas Wright, 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 King-
dom of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "A NEW OR IMPROVED METHOD OF AND APPARATUS FOR PRE-
VENTING THE EXPLOSION OF OR INJURY TO STEAM BOILERS THROUGH DEFICIENCY OF
WATER, upon the condition (amongst others) that I, the said Edwin Thomas
Wright, 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

page_text: 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 Edwin Thomas Wright, 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 :-
My said Invention consists in connecting a water buoy or float in the steam
boiler with the furnace door, or with a door opening into the furnace, as
herein-after particularly explained, and illustrated in the accompanying Draw-
ing, so that when the water in the boiler falls below a given level, the said
door is opened. By the opening of the said door cold air is admitted into the
furnace, whereby the boiler is cooled, and the draught through the fire to a.
great extent suspended. The overheating and consequent danger of explosion
of the boiler is thereby prevented, and the attendant on proceeding to fire is
warned of the state of the water in the boiler by the open door.
I have represented in the accompanying Drawing several modifications of
my Invention.
Figure 1 represents in vertical longitudinal section an egg-ended boiler to
which my Invention is applied, and Figure 2 is an end elevation of the same.
As
a is a float, connected by means of the lever b6 with the furnace door c.
the float a descends by the sinking of the water in the boiler below the proper
level, the furnace door c is raised, the draught through the burning fuel at d
is thereby checked, and the boiler is cooled by the current of cold air entering
at the door c. I sometimes connect the float in the boiler with the furnace
door by means of a chain and pulley, as illustrated in Figures 3 and 4,
Figure 3 being a vertical longitudinal section of a steam boiler with an interior
furnace to which my Invention is applied, and Figure 4 being a transverse
vertical section of the same. e is the float hung to the lever f in the boiler.
The said leverf turns upon a fulcrum at 9; a chain h passing over the pulley i
connects the float e with the furnace door k. By the descent of the float e
the furnace door k is raised. In boilers of the kind represented in Figures 3
and 4 the distance between the water level and the furnace flue is sometimes
insufficient to allow of the descent of the float through the requisite distance
when the said float is immediately over the said flue. On this account the
float is placed on one side, as shown in Figure 4.
Figures 5 and 6 represent another method of carrying my Invention into
effect; Figure 5 representing a vertical longitudinal section, and Figure 6 an
end elevation of a boiler to which my Invention is applied. In this modifica-

page_text: tion of my Invention the furnace door opens in the ordinary manner, that is
to say, turns upon a hinge or axis at m instead of rising by the vertical sliding
motion described with reference to Figures 1, 2, 3, and 4. n is the float, a
chain from which passes over the pulley o, and is terminated by the counter-
poise p. On the axis of the pulley o is a bevilled toothed wheel q, which takes
into the bevilled toothed wheel r on the vertical shaft or spindle s. The
furnace door is fixed on the lower end of the shaft or spindle s. As the
float n descends, a rotatory motion is communicated to the pulley o, the said
motion being transmitted through the axis of the pulley o, the bevil gear q, r,
and the shaft or spindle s, to the furnace door 1; the said furnace door being
thereby opened, cold air is admitted, the draught through the fire is checked,
and explosion of or injury to the boiler prevented. I sometimes also connect
a whistle, bell, or other alarum with the apparatus described and represented,
so that attention is immediately called to the opening of the door. As the
sounding of a whistle, ringing of a bell, or the actuating of any other alarum
by the descent of a float, or by the opening of a boiler door, may be effected
by a great variety of well-known contrivances, and as the sounding of a whistle-
or the actuating of any other alarum constitute only a useful adjunct to, but
no essential part of my Invention, I do not think it necessary to describe or
represent the methods whereby an alarum may be sounded by the descent of a
float or the opening of the furnace door. Instead of connecting the float to
the ordinary furnace door, that is to say, to the door by which fuel is supplied
to the furnace, I sometimes connect the float to a separate air door, but
I prefer generally to connect the float with the fire door, because in this case
the apparatus is put in motion and its perfect condition ascertained whenever
the door is opened for firing. The manner in which I carry my Invention
into effect when I use a separate air door will be understood by assuming the
several doors c, k, and l, in the Drawing to be the said separate doors, and
that additional and ordinary furnace doors are employed for the purpose of
supplying fuel to the furnace.
Having now described the nature of my 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 details herein described and represented, as the same may
be varied without departing from the nature of my Invention; but I claim as
my Invention the method of, and apparatus herein-before described and
represented in the accompanying Drawing for, preventing the explosion of and
injury to steam boilers through deficiency of water, that is to say, connecting a
float in the interior of the boiler with the furnace door or with a separate air.

page_text: door, in such a manner that when the water in the boiler descends below its
proper level, the said furnace or air door is opened and a current of cold air
admitted, the said current of cold air suspending the draught through the fire,
and also cooling the boiler.
In witness whereof, I, the said Edwin Thomas Wright, have hereunto
set my hand and seal, this Twenty-first day of March, in the year of
our Lord One thousand eight hundred and fifty-nine.
Witness,
GEORGE SHAW.
EDWIN THOMAS WRIGHT. (L.B.)