AN Improved SafeguARD OR MEANS FOR PREVENTING THE EXPLOSION OF BOILERS IN RANGES AND HOT WATER APPARATUS
Year: 1871

page_text: LETTERS PATENT to Joseph Russell, of Dorset Street, in the City of
London, Engineer, for the Invention of "AN Improved SafeguARD OR
MEANS FOR PREVENTING THE EXPLOSION OF BOILERS IN RANGES AND HOT
WATER APPARATUS."
Sealed the 14th March 1871, and dated the 7th January 1871.
PROVISIONAL SPECIFICATION left by the said Joseph Russell at the
Office of the Commissioners of Patents, with his Petition, on the
7th January 1871.
· I, JOSEPH RUSSELL, of Dorset Street, in the City of London, Engineer,
do hereby declare the nature of the said Invention for.“ AN IMPROVED.
SAFEGUARD OR MEANS FOR PREVENTING THE EXPLOSION OF BOILERS IN RANGES AND
HOT WATER APPARATUS," to be as follows:-
•
"
My Invention relates to an improved means of preventing the ex-
plosion of the closed "boilers" of water heating apparatus such as
those employed in kitchen ranges and stoves. Hitherto such “boilers
have been liable to burst if unprovided with any independent means of
escape for the steam which may accumulate therein when the water

page_text: pipes communicating therewith become stopped by reason of the water
contained therein becoming frozen or from other cause, and the object
of my Invention is to provide a means of escape for the steam under
those circumstances. For this purpose I provide a hole in the upper
part of the "boiler" which I cover with a material (india-rubber or
thin sheet metal for example) of sufficient strength to withstand any
ordinary or reasonable pressure to which the boiler may be subjected,
but which will burst and allow of the escape of the steam generated
under excessive pressure. I clamp the india-rubber or other diaphragm
securely to the boiler by means of a flanged tube fastened by bolts so as
to make a water-tight closure, which tube serves to carry off the steam
when the rupture of the diaphragm takes place.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Joseph Russell in the Great Seal Patent Office on
the 7th July 1871.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPH
RUSSELL, of Dorset Street, in the City of London, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of January, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty-
fourth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Joseph Russell, Her special licence
that I, the said Joseph Russell, my executors, administrators, and assigns,
or such others as I, the said Joseph Russell, 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 AN IMPROVED SAFEGUARD OR MEANS FOR
PREVENTING THE EXPLOSION OF BOLLERS IN RANGES AND HOT WATER APPARATUS,”
upon the condition (amongst others) that I, the said Joseph Russell, 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
+

page_text: the same was to be performed, and cause the same to be filed in thê
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 Joseph Russell, 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
following statement, reference being had to the Sheet of Drawings
hereunto annexed, and to the letters and figures marked thereon (that
is to say):
My Invention relates to an improved means of preventing the ex-
plosion of the closed "boilers" of water heating apparatus such as
those employed in kitchen ranges, bath; and other stoves. Hitherto
such "boilers" have been liable to burst if unprovided with any means
of relieving the pressure caused by the expansion of the heated water;
or the accumulation of steam when the water circulation tubes com-
municating therewith become stopped by the freezing of the water
contained in the said tubes, or from other cause, and the object of my
Invention is to provide a means of escape under those circumstances
and so relieve the boiler of any undue pressure. For this purpose I
provide a hole in the upper part of the "boiler "which I cover with a
material (india-rubber or thin sheet metal for example) of sufficient
strength to withstand the ordinary or normal pressure due to the height
of the column of water from the supply cistern, but which will burst
under excessive pressure, and allow of the escape of any steam that may
be generated.

page_text: shell a suitable packing E being interposed as shown to make a water-.
tight closure. I employ an ordinary packing of hemp and red lead for
this purpose. The socket C is cast of the form shown with a raised
ridge C¹ on the under surface of the flange to prevent the packing E
squeezing out of place, and with an inner shoulder F against which the
bursting plate B is firmly clamped by a copper ring G secured by screws
received in corresponding holes tapped in the socket C. A packing
in the form of a ring or washer of vulcanized sheet india-rubber I is
interposed between the plate B and the shoulder F to make a water-
tight joint which may be luted with white lead, grooves F¹ being formed
in the shoulder F to prevent the packing being displaced; H is a pipe
screwed into the socket C or cast in one therewith and leading by means
of additional lengths to any convenient outlet (through the wall of the
house or down into a drain for instance) so as to carry off the steam
and water when the plate B is ruptured.
Figure 4 shows a vertical part sectional elevation, and Figure 5 an
under side plan with the diaphragm removed of a similar safeguard, in
which the diaphragm is of vulcanized sheet india-rubber. In this case
the shoulder F is cast with an annular groove or recess F" near its inner
edge in which the disc of india-rubber is securely clamped and held at
a distance from its edge by a corresponding raised ridge G₁, formed on
the ring G, whereby a water-tight joint is ensured. In either case the
thickness of the diaphragm must be regulated according to the strengthi
of the material employed and the area exposed to the pressure in
the boiler, so that it shall not fail to burst if the pressure exceeds
the ordinary and proper limit. The diaphragm may be clamped directly
to the boiler by the flange of the tube or socket C, as shown in Figure 6
a water-tight joint being made by a hemp and red lead ring or packing E,
I however prefer the method of securing the diaphragm shown in
Figures 1 and 2 especially if india-rubber be used as it is less liable to
be affected by the heat of the boiler when not placed in immediate
contact with the boiler shell.
Having described the nature of my Invention, and the manner of
performing the same, I declare that what I claim as my Invention to
be protected by the herein-before in part recited Letters Patent is,-
'
1st. The application of a diaphragm or "bursting plate" to an aperture
made in the closed boilers of ranges and hot water apparatus as and for
the purpose set forth.

page_text: 2ndly. I claim the combination with the diaphragm or bursting plate
of a flanged tube, or socket and tube, for carrying off the water and steam,
the whole arranged and applied substantially as herein-before described
and illustrated in the Drawings.
In witness whereof, I, the said Joseph Russell, have hereunto set
my hand and seal, this Sixth day of July One thousand eight
hundred and seventy-one.