CERTAIN IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM BOILERS
Year: 1856

page_text: LETTERS PATENT to Sven Johan Agrell Burg, of No. 1, Serle Street,
Lincoln's Inn, in the County of Middlesex, for the-Invention of "CERTAIN
IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM BOILERS."
-
_ A communication from William Palmer, of the City of New York, in
the United States of America.
PROVISIONAL SPECIFICATION left by the said Sven Johan Agrell Burg
at the Office of the Commissioners of Patents, with his Petition, on
the 22nd July 1856.
I, SVEN JOHAN AGRELL BURG, of No. 1, Serle Street, Lincoln's Inn, in the
County of Middlesex, do hereby declare the nature of the said Invention for
"CERTAIN IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM BOILERS,"
(a communication) to be as follows:-
The nature of this Invention consists in making a double tubular case or
box, which is attached to the head of the boiler by an upper and lower.
connecting pipe, so that the upper pipe communicates with the boiler above
the range of the water line, and the lower pipe with the boiler below the range,
so as to admit the water as well as the steam into the case, where, consequently,
the water will rise and fall with the water in the boiler. Inside of this case at
the head, and about midway between the two tubes, is arranged a lever on a
pivot, to one end of which is attached a rod, having on the lower end of it a
float, to rest upon the water in one of the tubes, and rise and fall with it. To:
the opposite end of the lever is also attached a rod, having ou its lower end a

page_text: compensating plate, to sink into the water in the tube in which it works, so as
to compensate the sudden rise and fall of the float in the opposite tube, in
consequence of the ebullition of the water or of the rolling of the vessel, when
applied to sea-going steamers. When this float sinks below a certain mark
the lever opens a valve in the head of the case, and the escaping steam causes
a little paddle wheel outside and in front of the case to revolve, which, by
means of a cam and a hammer, rings the bell on top of the case. When
the water and consequently the float rises too high the lever opens another
valve, and the escaping steam sets the same paddle wheel in motion and rings
the same bell; but this time the steam escapes in a different direction from the
paddle wheel, and indicates to the engineer that the water is too high. The
great advantage of this apparatus is, that its external application to the boiler
renders it accessible to examination for repairs if out of order, a matter of
great importance where gauges are used.,
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Sven Johan Agrell Burg in the Great Seal Patent Office
on the 24th September 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SVEN
JOHAN AGRELL BURG, of No. 1, Serle Street, Lincoln's Inn, in the County
of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by 'Her Letters
Patent, bearing date the Twenty-second day of July, in the year of our Lord
One thousand eight hundred and fifty-six, in the twentieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Sven Johan Agrell Burg, Her special licence that I, the said Sven Johan'
Agrell Burg, my executors, administrators; and assigns, or such others as I;
the said Sven Johan Agrell Burg, 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 CERTAIN IMPROVED APPARATUS FOR PREVENTING THE EXPLOSION OF STEAM
BOILERS," a communication from William Palmer, of the City of New York;
in the United States of America, upon the condition (amongst others) that I,
the said Sven Johan Agrell Burg, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and seals,

page_text: 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.
うた
..NOW KNOW YE, that I, the said Sven Johan Agrell Burg, 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 in writing, reference being had to the Drawings hereunto
annexed, and to the letters and figures marked thereon, that is to say:-
This improved apparatus consists of a combined steam and water guage and
alarm bell, and is constructed as follows:-A double tubular case or box,
which is attached to the front end of the boiler by an upper and lower
connecting pipe, so that the upper pipe communicates with the boiler above
the level of the water line, and the lower pipe with the boiler below the said
level, so as to admit the water as well as the steam into the case, where,
consequently, the water will rise and fall with the water in the boiler. Inside
of this case at the upper part, and about midway between the two tubes, is
arranged a lever on a pivot, to one end of which is attached a rod, having on
the lower end of it a float to rest upon the water in one of the tubes, and rise
and fall with it. To the opposite end of the lever is also attached a rod, having
on its lower end a compensating plate, to sink into the water in the tube in
which it works, so as to compensate any sudden rise and fall of the float in the
opposite tube, in consequence of the ebullition of the water or of the rolling of
the vessel, when applied to sea-going steamers. When this float sinks below a
certain mark, the lever opens a valve at the upper part of the case, and the
escaping steam causes a small paddle wheel outside and in front of the case to
revolve, which, by means of a cam and a hammer, rings a bell on top of the
case, or at any other convenient place. When the water (and consequently
the float) rises too high, the lever opens another valve, and the escaping steam
sets the same paddle wheel in motion and rings the same bell; but this time
the steam escapes from the paddle wheel in a different direction, and indicates
to the engineer that the water is too bigh. The great advantage of this
apparatus is, that its external application to the boiler renders it accessible for
examination or repairs if out of order, a matter of great importance where
guages are used.
But in order to describe this Invention more particularly,. I will refer to the
accompanying Drawings, in which the same letters of reference, wherever they
occur in the several Figures, indicate corresponding parts of the apparatus.
Figure 1 is a front elevation of the apparatus; Figure 2 is a vertical section
:

page_text: of the guage, taken through the line X, X's and Figure 3 is a vertical section,
taken through, the line Y
A is the case of the guage, which is composed of two halves, having a flange
around its edges, so as to admit of, being bolted together to make the case
steam-tight. The case consists of two hollow tubes B1, B2, the bores of which
unite at the top, where a lever C is mounted on a standard D within the case;
this lever is long enough to have its ends vertical over about the centres of
the hollow tubes. To one end of this lever is attached a rod E, having a float
Fon its lower end, and on the opposite end of the lever is another rod G,
having on its lower end a compensating plate H. The use of the float is to rest
on the water, which flows into the tubes of the case through the connecting
pipes I and J, and risc. and fall with it; but when it rises too high, it opens by
'means of the lever C the valve M, which is connected with the lever C by a
rod M; and when the water falls too low, it opens, by means of the same lever
C the valve N, connected with the lever C, by the rod N¹. In both cases
'steam escapes through the valves, passes through the pipes O or P in oblique
directions,into a circular case Q, and causes the paddle wheel R to revolve. This
paddlewheel is composed of two flanges, which form a groove between them to
ruceive six or more paddles S; these paddles may be set either square or obliquely,
as shewn in Figure 1 in dotted lines, and the bottom of the groove may be
worked straight between each pair of the paddles, as shewn plainly in the same
Figure in dotted lines, so as to secure the most favourable action of the steam
against the paddles. This wheel turns freely on a pin T, placed in the centre
of the case which case fits all round the wheel (so as to prevent the escape
of steam out of the wheel R) without touching anywhere. But in order
to give the steam an outlet from the wheel, the surrounding case Q is provided
with two openings for the escape of the steam; consequently, when steam
enters into the case Q through the tube O, in consequence of the water in the
boiler being too high, it turns the paddle wheel R in the direction of the arrow,
and the steam remains within the paddles S, until they reach the opening U,
where it will escape. When steam enters into the case Q through the tube P;
in consequence of the water being too low, it will also put the paddle wheel R
in motion, but the steam will escape through the opening U¹; consequently,
the direction in which the steam escapes will indicate to the engineer whether
the water in the boiler is too high or too low. The boss of the wheel R is
provided with a cam R', which when in motion raises the lever V each
revolution, and causes the hammer V₁ to strike the bell W. The use of the
compensating plate H is to prevent the sudden action of the float in con-
sequence of the ebullition of the water in the boiler, or in cousequence of the

page_text: rolling of the boiler in a sea-going vessel. This is done by sinking the plate
H in the water in the tube B', and as it nearly fits the orifice of the cylinder
or tube B', there will always be a weight of water on it requiring time to
escape, and consequently acting as a compensator to the tendency of the float
to follow the vibrations of the water, which would, without the compensator,
cause a constant ringing of the bell. Should one compensating plate not be
sufficient, two or more may be used, as the weight of the float may require.
X represents the end plate of the boiler, to which the connecting pipes are
attached. These connecting pipes have plugs Y, Y, in them, so that if any
accident should require the removal of the guage, it can be effected without
any trouble. Z is a blow-off pipe, communicating with the connecting pipe of
the guage, so as to blow off the water in the guage when required. I would
here remark, that in order that the level of the water may be at all times
visible, a strong piece of plate glass may be let in the front of one or both of
the tubular cases B', B³.
Having now described the nature and object of the said Invention, together
with the manner of carrying the same into practical effect, I would remark, in
conclusion, that I claim, as the Invention secured to me by the above-named
Letters Patent, the use or application of a lever, having a float at one end of it
and a compensating plate at the other, whether working in a double tubular
case or otherwise, in combination with an upper and lower valve, for sounding
a bell by means of the steam escaping through these valves, whether using the
paddle wheel or any equivalent device for that purpose, to indicate the
minimum or maximum height of the water in the boiler, substantially as set
forth.
In witness whereof, I, the said Sven Johan Agrell Burg, have hereunto
set my hand and seal, this Twenty-fourth day of September, in the year
Signed and sealed in the presence of
BRISTOW HUNT,
Solicitor & Patent Agent,
S. J. A. BURG. (L.S.)
1, Serle Street, Lincoln's Inn, London.