Year: 1886

page_text: BLOG DOROT FULACUS.
I, PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane, in the County of
Middlesex Fellow of the Institute of Patent Agents do hereby declare the nature
of this invention (a communication to me from abroad by Nelson Curtis of Boston,
Massachusetts, United States of America) and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
The invention relates to that class of damper regulators in which steam from
the boiler, whose fires it is desired to regulate, is employed for moving the damper
in one direction, while a weight is employed for moving the damper in the other
direction, no steam from the boiler being required except when it is desired to
overcome the force of the weight. The object of the invention is to provide an
exceedingly sensitive apparatus.
.
The damper is so balanced or weighted as to normally stand open. Its lever is
connected by a chain passing over suitable pulleys with the piston of a steam
cylinder so that when steam is admitted to the piston it will overcome the tendency
of the damper to stand open and close it, but there is normally no steam pressure
upon the piston. Steam is admitted to the cylinder when required to operate the
piston through a port controlled by a piston valve that works in a steam chamber
always open to the boiler. Normally the steam pressure in this steam chamber
above and below the piston of the piston valve is equal, but above the piston is an
exhaust port which normally is closed by an auxiliary valve acting under the force
of a weight or spring equal to the desired boiler pressure. This auxiliary valve
is in effect a diaphragm valve whose diaphragm is always exposed to steam at
boiler pressure. When the steam pressure upon the diaphragm overcomes the force
of the said spring or weight the auxiliary valve opens, thereby relieving the pressure
above the main valve and causing the main valve to open and admit steam to the
piston that is connected to the damper lever.'
The invention consists in the combination with a steam boiler, a furnace, a flue,
an unbalanced damper in said flue, a steam cylinder provided with a piston
mechanically connected with said chamber, and a steam passage connecting said
boiler with said steam cylinder, of further steain connections and valve mechanism
therein, in a manner hereinafter fully set forth. It also consists in a detail of
construction.

page_text: To clearly explain the nature of the invention reference is made to the
accompanying drawings in which :-
Fig. 1 is an elevation of apparatus embodying my invention.
Fig. 2 is a partial sectional elevation of the same upon an enlarged scale.
A, is the furnace, B, is the boiler, C, is the flue, D, is the damper, E, is an upright
steam cylinder firmly fixed as shown to the wall of the boiler room. At its lower
end it has a cylinder head E¹ through which a piston rod F, works the said head.
being provided with a stuffing box and also with a circular projection a G is a
cup shaped piston having a minute adjustable port b, in its working surface, as
shown. E is the cylinder head at the upper end of the cylinder, containing &
port c. This cylinder head E' is hollow and contains a large portion of the main
valve mechanism of the apparatus. It is tightly closed at the upper end by a
flexible metallic cap or diaphragm d, which is held in place, as shown, by a casting H,
which is bored out to receive and hold apparatus, acting as a weight upon the
said diaphragm, consisting of a follower f, a screw-handle H and a spring 8.
J, is a piston valve for the port c. It is furnished with a spindle working through
the port c, as shown, in order that the said port may be sufficiently small when
open. The piston of the valve J, is cup-shaped and is provided with a spring 8¹
that finds a resistance against a block K, screwed into the casting H, below the
diaphragm d. The block K is bored out to contain the greater part of a second or
auxiliary valve mechanism; being the valve, m, being a passage way through the
block and n being the valve port, while p, is a recess in the said block carrying a
springs, which presses against a flange upon the top of the valve to cause the
valve to follow the movements of the diaphragm.
A chamber (marked P) in the casting H, below the piston of the piston valve J,
is connected with a chamber P¹, above the block K, and below the diaphragm d,
by a passage way t, bored in the casting H, as shown.
R, is a pipe or passage way connecting the chamber P, with the boiler. R¹ is a
drain pipe leading from the lower end of the cylinder E, and R' is an exhaust pipe
for the auxiliary valve connecting the passage way m, with the lower end of the
cylinder E.
T, is a double yoke, the crossbars c¹, c², of which are connected by two rods r, r,
passing through holes in flanges of the cylinder head as shown. The lower cross
bar ², of the yoke is secured to the piston rod F while the upper bar c¹ carries a
hook e¹, that is connected by a chain e, with the lever of the damper. W, is a
weight attached to the lever of the damper to operate it in one direction.
The operation is as follows:-
We will assume, as is the case, that normally there is no steam in the cylinder E,
above the piston G. Accordingly the weight W opens the damper and draws up
the yoke T, and with the yoke the piston G, to the upper limit of motion of the
latter, which is determined by the 'cross bar c³, striking the boss ring a, upon the
lower cylinder head. There is constantly full boiler pressure in the pipe R, and
consequently there is always full boiler pressure in the chamber P, and likewise in
the chamber P¹, which is connected with chamber P by the ever-open passage way t.
Moreover the piston of the valve J, fits somewhat loosely in the chamber P, or there
may be a pin-hole through it, and accordingly there is normally full boiler pressure
in the chamber P above as well as below the piston of the valve J. The valve J,
therefore under gravity, or assisted by spring s¹ falls and normally rests upon its
seat to close the port c.
It is obvious that the exact construction shown is not of the essence of my
invention broadly considered. For instance the cylinder E with its piston G and
yoke T might be located near the flue while the valve mechanism might be placed
near the boiler at a distance from the flue, a suitable pipe connecting the port c,
of the chamber P, with the cylinder.
Again the valve l, with spring s³, diaphragm d, and spring 8, so far as my
invention is concerned, is but the equivalent of a weighted valve working across
an exhaust passage way at the end of chamber P, above the piston of valve J.

page_text: As before pointed out the spring 8, keeps the valve in contact with the
diaphragm d, whatever may be the position of the latter. In fact the valve and
diaphragm together are in effect a piston valve pressed down towards the valve
seat to close the port n, by whatever force may be given to spring 8, by turning
the screw handle H¹. The lower surface of the diaphragm d closes the top of the
chamber P¹, which as before stated is constantly full of steam at boiler pressure.
Accordingly the springs is adjusted to resist the exact boiler pressure which it is
desired to maintain. Any, (the least) excess of boiler pressure will overcome the
force of the spring 83, and open the valve port n. This will allow the steam which.
lies in chamber P, above the piston of the piston valve J, to escape through port n,
passage way m, and exhaust pipe R. Accordingly the valve J now rises, and
steam passes through port c into the cylinder above the piston G and forces that
piston down and with it the yoke T, to overcome the weight W, and close the
damper. When the fires are sufficiently reduced and the steam pressure falls below
the pressure to which the valve has been adjusted, the valve will close, when
the equilibrium of pressure above and below the piston of piston valve J being
restored the latter valve will also close, and the piston G, will rise under the force
of the weight W, and the damper will open the steam in the cylinder E, above the
piston G, leaking through the minute port b. So also without departing from my
invention the chamber P¹ might take its steam directly from the boiler instead of
through chamber P and passage way t.
In the construction shown however, the chamber P may be regarded as a con-
tinuation of the main steam passage, entering the cylinder head E' from pipe R,
continuing through port c, and controlled by valve J, while a branch exhaust
is shown consisting of the passage by the piston of the valve J, (owing to its loose
fit) a hole shown in dotted lines in block K, while port n, and passage m, are
controlled by valve l.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is :-
1. The combination with a steam boiler, a furnace, a flue, an unbalanced damper
in said flue, a steam cylinder provided with a piston mechanically connected with
said damper and a steam connection between said boiler and said steam cylinder,
of two steam chambers, one of which, being an enlargement of said passage way
leading to said cylinder, is provided with a piston valve normally closing said
passage way and has an independent escape or exhaust passage, while the second
chamber is provided with a weighted valve normally closing said independent
exhaust passage of the first chamber and has a steam communication opening into
it from the boiler to oppose the weight of said weighted valve, substantially as
described.
2. The combination with the cylinder E, provided with piston G, piston-rod F,
and perforated head E¹, of chambered cylinder head E', provided with port c,
valve J, auxiliary valve l, a main steam passage way leading to said port c, and a
branch steain exhaust passage leading from said main passage, the said valve J
being in the main passage and the said auxiliary valve being in the exhaust
passage, substantially as described.