A NEW OR IMPROVED APPARATUS FOR PREVENTING EXPLOSIONS IN STEAM BOILERS
Year: 1853

page_text: LETTERS PATENT to John Rollinson, of Kingswinford, in the
County of Stafford, Engineer, and William Rollinson, of Brierley
Fill, in the County of Stafford, Engineer, for the Invention of
"A NEW OR IMPROVED APPARATUS FOR PREVENTING EXPLOSIONS IN
STEAM BOILERS."
Sealed the 2nd January 1854, and dated the 2nd July 1853.
PROVISIONAL SPECIFICATION left by the said John Rollinson
and William Rollinson at the Office of the Commissioners of
Patents, with their Petition, on the 2nd July 1853.
We, JOHN ROLLINSON, of Kingswinford, in the County of Stafford,
Engineer, and WILLIAM ROLLINSON, of Brierley Hill, in the County of
Stafford, Engineer, do hereby declare the nature of the said Invention
for "A NEW OR IMPROVED APPARATUS FOR PREVENTING EXPLOSIONS IN
STEAM BOLLERS" to be as follows:-
Our Invention consists of an arrangement to be applied to steam
boilers, whereby a safety valve is opened in case the pressure of the
steam become too great or the water in the boiler sink too low, the
communication between the said boiler and any other boiler with which

page_text: it may be connected is at the same time cut off. The Drawing
represents one modification of our Invention. The wire «, is con-
nected with a float in the boiler, and when the water and float
descend below a certain point the arm b, is raised, and the valve e,
closed, through which the boiler communicates with the adjoining
boiler. If the pressure of the steam becomes too great, then the
weighted piston f, is raised, and the rod of the said piston raises the
lever b, and, opens the valve. c,, so as to permit the steam to escape,
and also closes the valve e. Where thought desirable, many of the
working parts may be placed in the interior of the boiler; but we do
not confine ourselves to any details, the principle of our Invention being,
that when the water is too low or the pressure of the steam too high a
valve is opened to permit the escape of the steam, instead of merely
giving a signal, as is usual, the communication with the adjoining
boiler being at the same time cut off.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Rollinson and William Rollinson in the
Great Seal Patent Office, on the 2nd January 1854:
TO ALL TO WHOM THESE-PRESENTS SHALL COME, we,
JOHN ROLLINSON, of Kingswinford, in the County of Stafford, Engineer,
and WILLIAM ROLLINSON, of Brierly Hill, in the County of Stafford,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Second-day of July; in the year of
our Lord One thousand eight hundred and fifty-three, in the seventeenth
year of Her reign, did, for Herself, Her heirs and successors, give and.
grant unto us, the said John Rollinson and William Rollinson, Her.
special licence that we, the said John Rollinson and William Rollin-:
son, our executors, administrators, and assigns, or such others as we,
the said John Rollinson and William Rollinson, our executors, admi-
nistrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the. terni.therein.

page_text: 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
APPARATUS FOR PREVENTING EXPLOSIONS IN STEAM BOILERS," upon the
condition (amongst others) that we, the said John Rollinson and
William Rollinson, by an instrument in writing under our hands and
seals, or under the hand and seal of one of us, 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.
NOW KNOW YE, that I, the said John Rollinson; do hereby
declare the nature of the said Invention, and in what' nianiuer the same
is to be performed, to be particularly described "and' ascertained in"and"
by the following statement thereof, that is to say: "
Our Invention consists of an apparatus or arrangement of mecha-"
nism to be applied to a steam boiler for the purpose of preventing
explosion of the same either from a deficient supply of water or from
too great pressure of the steam in the said boiler; in either of which
cases our new or improved apparatus opens a safety valve, and at the
same time closes the communication (should there be any) between the
said boiler and any other boiler or boilers with which it may be con-
nected. The Drawing represents in vertical section a portion of a
steam boiler to which our Invention is applied. a, is a wire connected
in the ordinary manner with the float b, in the boiler; the said wire a,
is connected with one end of a chain c, which passes over the pulley d;
the other end of the said chain carries a counterpoise e. f, is a valve
pressed upon by the weighted lever g; the moveable end of the lever g,
is jointed to. another lever, as represented; the second lever his
jointed to the interior of the case i, in which the safety valve f, and its
appendages are enclosed. A wire k, connected with the bottom of the
counterpoise e, passes through the top of the case i, and also through
holes in the the levers g, h, as represented. A nut 1, is screwed on the
lower end of the wire k, the said nut being of such size that in rising it
passes readily through the lever g, but being too large to pass through

page_text: the lever h, raises the said lever h. m, is a cylinder fixed on the top
of the boiler. n, is a piston in the cylinder m; the rod o, of which said
piston is loaded by weights p; the said weights being varied according
to the maximum pressure which it is intended the steam in the boiler
shall have. The top of the piston rod o, is immediately under the
lever h; and when the piston n, is at the bottom of the cylinder m; the
top of the piston rod o, does not bear against the said lever h. q, is a
valve which opens or closes the communication between the boiler and
any other boiler or boilers which may be worked therewith. The
counterpoise, maintains the said valve open when it is not closed in
the manner herein-after described. The wire a, passes through the
end of the levers, of the valve q. The action of the several parts of
our new or improved apparatus is as follows: when the water in the
boiler and the float b, sink to the line t, the nut 1, bearing against the
under side of the lever h, raises the said lever, and through it the lever
g, and valve f, thereby permitting the steam in the boiler to escape, the
stop or nut u, on the top of the wire a, at the same time bears upon
the lever s, and closes the valve q, thereby preventing the ingress of
steam from the adjoining boiler. If the water in the boiler preserves
its proper level, but the pressure of the steam becomes too great, then
the piston n, is raised, and the top of the piston rod o, bears against the
under side of and raises the lever h, thereby opening the valve f, and
retaining the said valve open until the pressure of the steam has fallen
to the proper amount, when the weights p, cause the piston n, to
descend, and the valve f, closes.
Having nowdescribed the nature of our said Invention, and the-
manner in which the same is to be performed, we wish it to be under-
stood that we do not confine ourselves to the method of carrying our
Invention into effect herein described, as the same may be varied
without departing from the nature of our said Invention; for example,
in low pressure boilers the nut 1, may be made to raise the lever g,
directly, and the lever h, may be dispensed with; the piston rod o, may
also be made to lift the said lever g, directly; but the modification we
have described is equally applicable to high and low pressure boilers.
We claim as our Invention an apparatus to be attached to a steam

page_text: boiler, which by means of a float and weighted piston opens a safety
valve either when the water in the boiler is too low or the pressure of
steam too high; the said apparatus also closing the communication
with any other boiler or boilers when the water is too low.
In witness whereof, I, the said John Rollinson, have hereunto set
my hand and seal, this Twenty-eighth day of December, in
the year of our Lord One thousand eight hundred and fifty-
three.
JOHN ROLLINSON. (L.S.)
0 Witness, GEORGE SHAW.