Improved Means and Apparatus for Regulating the Temperature of Steam Heated Stoves and the Pressure in Boilers Used for Heating by Low Pressure Steam.
Year: 1889

page_text: Date of Application, 2nd May, 1889-Accepted, 15th June, 1889
JUMIT LEIE
[Communicated from abroad by THE FIRM OF KORTING BROTHERS, of 62, Cellerstrasse,
Hanover, in the German Empire, Engineers.]
Improved Means and Apparatus for Regulating the Temperature of
Steam Heated Stoves and the Pressure in Boilers Used for Heating
by Low Pressure Steam.
I, ERNEST DE PASS, of 68 Fleet Street, in the City of London, Fellow of the
Institute of Patent Agents, do hereby declare the nature of this 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 accompanying drawings
and to the letters and figures marked thereon, that is to say :-
This Invention has for its object improved means and apparatus for regulating the
temperature of steam heated stoves and the pressure in boilers used for heating by
low pressure steam.
Heretofore considerable difficulty has been experienced in consequence of the
temperature rising too high in the heating stoves used for warming buildings, and in
boilers of steam heating apparatus, thus giving rise to serious inconvenience by “over-
boiling" of the boiler and excessive steam pressure in the heating stoves.
Both these evils are now overcome by means of the invention about to be
described.
In carrying out the Invention I regulate the temperature of the heating stoves by
allowing water to rise therein from a cistern placed at a higher level and connected
by means of pipes forming a "syphon," the rise of such water being controlled by
means of a cock or valve situated on the steam pipe leading from the boiler to the
heating stove. A pipe also connects the boiler with the cistern.
Fig. 1 of the annexed drawings illustrates this arrangement. a is the boiler, b the
cistern,, c, c, c, the heating stoves which are placed in the several rooms to be
warmed, d, d, d, d, are cocks or valves for regulating the steam that enters the stoves
from the conducting pipe e, connected to the boiler. f is a pipe connecting the boiler
with the cistern, this pipe always contains a column of water sufficient to withstand
the steam pressure in the boiler. g, and i are pipes connecting the stoves with
the cistern, and which pipes, as will be seen, form a "syphon," of which is the
longer leg, and g the shorter. When all the cocks d are closed, and steam so prevented
from entering the stoves, water from the cistern b will rise in them; but whenever
anyone or other of the cocks is opened, steam will enter that stove and act upon the
column of water in the pipe and cistern b, and will depress the surface of the water
in the stove according to the amount the cock has been opened. The stove thus
becomes more or less filled with steam and gives off more or less heat in proportion.
The length of the pipe 9 must be such that steam can never find its way from the
stoves into the pipe h. When several floors have to be heated, each floor has a separate
and distinct system of pipes and cistern similar to fig. 1. By means of a draw-off
cock k each system can be emptied of water without interfering with any of the
others.
To regulate the temperature of the boiler, I control the admission of air to the
furnace so that the generation of steam in the boiler may be more or less retarded.
Fig. 2 shews one method of doing this. a is the boiler, ba cylinder in which is a
floating piston c, d and e are chambers or vessels containing mercury, they are con-
nected to the cylinder b at the bottom by means of the pipes d and e¹. The chamber d
is connected at its top by the steam pipe f which leads to the boiler, and the chamber e
is connected at its top by means of the pipe g to the safety pipe G.
is the valve
controlling the air draught to the furnace; it is opened more or less by the rise or
fall of the floating piston c to which it is connected by means of the rod k¹, and the
DQ11

page_text: lever turning on a fulcrum at 3. Should the combustion going on in the furnace
become too fierce and the pressure in the boiler rise above the desired limit, the
mercury contained in the chamber d will be forced through into the cylinder b, and
raise the floating piston c, by which means the valve h will be closed and the air
draught shut off from the furnace. The fire then gets low and is kept down until the
steam pressure in the boiler has returned to its normal state. Should the pressure rise
so high as to overcome the column of water in the safety pipe G, the lower end of
which dips slightly under the surface of the water in the boiler, the water will be forced
out of this pipe until the lower end becomes exposed, and the steam having then a
free outlet through this pipe to the atmosphere the pressure will immediately fall. In
so doing, the valve would, by means of the arrangement just described, again open
and the air be once more admitted to the furnace and the steam having now a free
communication with the atmosphere through the pipe G, the whole of the water in
the boiler might be evaporated and the boiler rendered useless through over heating of
the boiler plates. In order to prevent such an occurrence the following arrangement
is employed whereby the valve is kept closed until released by the attendant, in case
overboiling" through the safety pipe has occurred. An additional mercury chamber e
is provided, and is so connected to the safety pipe G, that when through excessive
pressure the water rises in the pipe G to the point of "overboiling" part of the water
runs over into g and there remains even after the steam pressure in the boiler has
again fallen. The column of water in g acts upon the mercury in e and so keeps the
floating piston up and the valve h closed until the drain cock g is opened and the
water in the pipe g allowed to flow out.
"
Figure 3 shews a modification of the apparatus described above. The valves for
regulating the supply of air are shewn connected direct to the floating piston c by
means of a spindle g,-b is the cylinder containing the floating piston which, in this
case, is hollow. d'is the pipe connecting the cylinder 6 with the mercury chamber d.
hand i are two valves fixed to the spindle g and moving with it; they are so formed
that they can enter and close the passages and ¹ and yet permit of the spindle still
continuing to rise until flanges and 2, on the valves, come against the metal
surrounding the passages h¹ and i¹. The valves and i are contained in a chamber Q
and control the air inlet q to the ashpit of the furnace. There is another chamber Q¹
containing a disc valve which, when lifted from its seat allows cold air to enter the
flue through the passage q'. This disc valve is not secured to the spindle g, but allows
the spindle to pass easily through it; it is lifted by a collar g' coming beneath it as
the spindle continues to rise. The valves h and are balanced so that they prevent
the draught of the chimney interfering with the proper regulation of air to the ashpit.
When the passages h¹ and are fully closed, the valve j is fully open, and so no air
enters the ashpit, and cold air enters the chimney, thus completely diminishing the
combustion in the furnace.
Having now described the Invention and in what manner the same may be carried
into effect I claim.
1. Regulating the temperature of stoves used for heating by steam, by means of
syphons capable of being periodically emptied, such syphons conducting water from an
elevated cistern to the stoves so that as the steam pressure is increased or diminished
in said stoves, by opening and closing cocks, the water from the cistern will rise and
fall therein; the overflow from the cistern being led to the boiler by means of an over-
flow pipe, substantially as described and shewn with reference to figure 1 of the
drawings annexed.
2. Regulating the temperature of boilers used for heating by low pressure steam,
by means of apparatus consisting of a valve which controls the air draught to the
furnace; a floating piston actuating such valve and working in a cylinder; a chamber
containing mercury which is connected with said cylinder and with the boiler, so that
as the pressure in the boiler rises the mercury is forced into the cylinder and the
floating piston caused to rise and control the air draught valve, all substantially as
described and shewn with reference to fig. 2 of the annexed drawings.

page_text: 3. Regulating the temperature of boilers used for heating by low pressure steam, by
means of apparatus consisting of a valve controlling the air draught to the furnace; a
floating piston actuating such valve and working in a cylinder; a chamber containing
mercury which is connected to said cylinder and to the safety pipe of the boiler by
means of a pipe furnished with a drain cock to enable said pipe being emptied, all
substantially as described and shewn with reference to fig. 2 of the drawings
annexed.
4. Regulating the temperature of boilers used for heating by low pressure steam, by
means of apparatus consisting of valves secured to a spindle which, as the spindle rises,
close the air entrance to the ash pit, and, by a further movement of the spindle open
the chimney to the cool air, so diminishing the combustion in the furnace, sub-
stantially as described and shewn with reference to fig. 3 of the drawings annexed.
Dated this 2nd day of May 1889.
ERNEST DE PASS,
68, Fleet Street, London.