IMPROVEMENTS IN REGULATING THE GENERATING OF STEAM IN STEAM BOILERS
Year: 1847

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
THARPE STEVENSON, of Upper Baker Street, Lloyd Square, in the County
of Middlesex, Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Eighth day of April,
One thousand eight hundred and forty-seven, in the tenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Tharpe Stevenson, my exors, adñors, and assigns, Her especial
licence, full power, sole privilege and authority, that I, the said William
Tharpe Stevenson, my exors, adiñors, and assigns, or such others as I, the
said William Tharpe Stevenson, my exors, admors, or assigns, should at any
time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, my Invention of "IMPROVEMENTS IN REGULATING THE GENERATING OF
STEAM IN STEAM BOILERS;" in which said Letters Patent is contained a proviso
that I, the said William Tharpe Stevenson, shall cause a particular descrip-
tion of the nature of my said Invention, and in what manner the same is to
be performed, by an instrument in writing under my hand and seal, to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited

page_text: Letters Patent, as in and by the same, reference being thereunto had, will
more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
William Tharpe Stevenson, do hereby declare that the nature of my Inven-
tion, and the manner in which the same is to be performed, are fully described
and ascertained in and by the following statement thereof, reference being
had to the Drawings hereunto annexed, and to the figures and letters marked
thereon, that is to say :-
My Invention consists, first, of applying apparatus to a steam boiler and
to the furnace or fire thereof, in such manner that the generation of steam
shall be regulated by the pressure of steam in the boiler. And, secondly, the
Invention consists of a mode of arranging the interior part of the boiler that
that portion of the boiler surface will have comparatively a small height of
water, and consequently the water will be more highly heated than other
parts of the water which are at a greater depth in the boiler; and according
as the water is caused more or less freely to flow from the greatest depth into
the shallower depth, so will the generation of steam be regulated. And in
order that my Invention may be most fully understood and readily carried
into effect, I will describe the means pursued by me.
Figure 1 shows a longitudinal section of a steam boiler and furnace;
Figure 2 a plan; and Figure 3 a transverse section thereof; the dampers
applied to the furnace, and the fire bars of the furnace being so arranged as to
move up and down according as the pressure of the steam rises or falls in the
boiler, whereby, when the steam is getting too high, the dampers will be placed
so as to intercept the heat passing to the boiler; the apparatus used acting
also as a safety valve. a, a, are two flaps or dampers moving on axes b, b, in
bearings c. c, such flaps or dampers being, when closed, capable for the most
part of preventing the heat of the fire passing to the boiler; d is a lever
pressing on the stem 6 of the valve f. The lever d moves on a fulcrum at 9,
as is shown; one end of the lever is weighted so as to counterbalance the
apparatus and offer to the piston a pressure just below that of the safety
valve n, so that the apparatus which regulates the intensity of the fire may
come into action, and thus, in most instances prevents the blowing off the
steam at the safety valve; the other end of the lever supports a cross head h,
from which descend connecting rods i, i, which are attached at their lower s
ends by pin joints to the parts of the frame j which carries the fire bars,
there being projections ³ from such frame ; which pass through openings h
in the brickwork of the furnace, as is shown, such projections being affixed
to the bars to which the connecting rods are attached; 1, 7, are standards

page_text: fixed to the frame j, which at their upper ends carry curved plates m, on
which the flaps a, a, rest; by this arrangement it will be evident that if the
valve be raised by reason of pressure of steam rising higher than it is desired,
the end of the lever will cause the fire bars to descend, and the flaps or
dampers.more or less to screen the fire from the boiler, which will quickly
reduce the heat of the furnace as respects its action on the boiler; n is a safety
valve. I would state that the means of applying heat to the boiler may be
7aried from those shown in the Drawing without departing from this part
of the Invention, the peculiarity of which is the so acting upon the appa-
ratus by which heat is applied to a steam boiler that the pressure of the
steam in the boiler shall be brought to act on the fire, and thus to govern
or control it when the steam rises too high in the boiler.
I will now describe the second part of my Invention. Figure 4 shews a
longitudinal, and Figure 5 a transverse section, of a boiler constructed accord-
ing to this part of my Invention. a, a, is the ordinary boiler; b, b, are
partitions which divide off the central portion of the water space of the boiler,
so that the water at the external portion c, c, of the water space may stand
higher than the central portion d, by which arrangement the water at
the sides c, c, will rise higher than the side flues e, e, and yet there will be
a comparatively small quantity of water in the boiler, for the main or central
portion & will contain little water, and the steam will be generated very
quickly immediately over the fire. The supply of water is to be into the side
compartment c of the water space, and it will flow over into the central
portion of the water space as required.
Having thus described the nature of my Invention, and the manner in which
the same is to be performed, I would remark that I do not confine myself
to the details shewn and described, so long as the peculiar character of my
Invention be retained. But what I claim is,-
First, the applying apparatus to steam boilers and fires so as to cause the
pressure of steam in the boilers to regulate or govern the state of the fire by
reducing the same as the steam rises too high.
And, secondly, I claim the mode of constructing boilers so as to regulate
the generation of steam as described in respect to Figures 4 and 5.
In witness whereof, I, the said William Tharpe Stevenson, have here-
unto set my hand and seal, this Eighth day of October, in the year
of our Lord One thousand eight hundred and forty-seven.
WILLIAM THARPE (Ls.) STEVENSON.

page_text: AND BE IT REMEMBERED, that on the Eighth day of October, in
the year of our Lord 1847, the aforesaid William Tharpe Stevenson came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.
Enrolled the Eighth day of October, in the year of our Lord One
thousand eight hundred and forty-seven.