IMPROVEMENTS IN AUTOMATIC DRAFT REGULATORS FOR STEAM BOILERS
Year: 1877

page_text: LETTERS PATENT to Herbert John Haddan, of the Firm of Herbert and Com
pany, Patent Agents, of 67, Strand, in the City of Westminster, Civil Engineer,
for the Invention of "IMPROVEMENTS IN AUTOMATIC DRAFT REGULATORS
FOR STEAM BOILERS." A communication from abroad by Reginald Fairfax
Hyde, of Springfield, Massachusetts, in the United States of America.
PROVISIONAL SPECIFICATION left by the said Herbert John Haddan at the
Office of the Commissioners of Patents on the 27th December 1877.
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Patent Agents,
of 67, Strand, in the City of Westminster, Civil Engineer. "IMPROVEMENTS IN
AUTOMATIC DRAFT REGULATORS FOR STEAM BOILERS." A communication from
abroad by Reginald Fairfax Hyde, of Springfield, Massachusetts, in the United
States of America.
The Invention consists in operating a draft regulator by fluid forced from the
boiler into an air chamber, and returned by the expansive force of the compressed
air.
The improvement is to be performed by using a cylindrical casing of any suitable
dimensions which is to be made fast to the wall or otherwise conveniently sup-
ported; in said casing is placed a coil of piping which forms a flexible oscillating
conduit joint; this piping is connected with the boiler and with a curved pipe
passing to the bottom of an air chamber of any suitable size.
Fluid is forced from the boiler into the coil, and through the curved pipe into
the air chamber, compressing the air therein; as the pressure decreases, the fluid is
forced back into the boiler from the air chamber by the expansive force of the air
previously compressed; the regulator is thus worked by means of a beam or lever
attached to it, or by other equivalent mechanical device."

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Herbert John Haddan in the Great Seal Patent Office on the 6th
June 1878.
"
HERBERT JOHN HADDAN, of the Firm of Herbert and Company, Patent Agents,
of 67, Strand, in the City of Westminster, Civil Engineer. IMPROVEMENTS IN
AUTOMATIC DRAFT REGULATORS FOR STEAM BOILERS." A communication from
abroad by Reginald Fairfax Hyde, of Springfield, Massachusetts, in the United
States of America.
The Invention consists in operating a draft regulator by fluid forced from the
boiler into an air chamber, and returned by the expansive force of the compressed
air.
The improvements are to be performed by using a cylindrical casing of any
suitable dimensions which is to be made fast to the wall, or otherwise conveniently
supported; in said casing is placed a coil of piping which forms a flexible oscillating
conduit joint; this piping is connected with the boiler and with a curved pipe
passing to the bottom of an air chamber of any suitable size.
Fluid is forced from the boiler into the coil, and through the curved pipe into the
air chamber, compressing the air therein; as the pressure decreases, the fluid is
forced back into the boiler from the air chamber by the expansive force of the air
previously compressed; the regulator is thus worked by means of a beam or lever
attached to it, or by other equivalent mechanical device.
The accompanying Drawings will serve to illustrate the mode of performing the
Invention.
Figure 1 is a front view; Figure 2, a part longitudinal section; and Figures 3
and 4 are detached detailed views.
A represents a cylindrical case or jacket of any convenient size, which is to be
fixed on a wall or other support to which it may be adapted. From the centre of
this jacket projects a horizontal arm E, having a longitudinal grooving or collar in
its upper side, as shown.
On the front end of the jacket A is placed a flange C provided with an annular
flange corresponding with and moving freely against the edge of the said jacket in
order to allow of the lateral motion caused by the oscillation of the driving lever,
and to which is attached the cap D; this cap has a stem or arm B projecting
towards the inside of its centre forming the support or bearing of the beam and its
different parts.
On the lower side of the stem B are formed knife edges b, b, which rest in the
groove or bearing a on the stem B, and on which they may be turned from one
side or the other.
On the back part of the jacket A and in the cap D are formed projections in
segments d, which may be turned back over the arms or stems B, B', by which they
are maintained in position. From one of the sides of the flange c projects a beam E,
which may be graduated or not, as desired, and on the end of this beam is formed
or attached a weight E', preferably in form of a ball; E2 represents a counter-
poise on the beam E, which is to be placed at any desired point, according to the
pressure which has to be maintained, and attached to this point by a set screw e or
otherwise. From the opposite side of the flange cand in the opposite direction to
the beam extends a hollow arm G having an air chamber H attached to its outer
end and which balances nearly or entirely the weight on the other end of the
beam.
On the outer end of the arm G is fixed the end of a tube I which is coiled in the
inside of the jacket A, effecting in some degree the work of a reel spring, and
the other end of the said tube is attached by a connection J to the jacket A. This
connection J is to be put in communication by a convenient pipe with the water
space of the boiler. In the outer end of the hollow arm G is screwed or otherwise
fixed a curved pipe K passing inside the air chamber H, and extending to the end

page_text: of that chamber, as shown in Figure 4. The air chamber H is full of air and ought
to be rendered perfectly air-tight and water-tight. The moderator or govenor thus
constructed, being connected by the spiral tube and hollow arm G with the water
space in the boiler, as is described.
The operation is as follows:-When the pressure in the boiler increases, the water
is forced by the steam into the coil I, through this latter, and through the hollow
arm G and tube K in the air chamber H, compressing therein the air in the upper
chamber. In proportion as the pressure of steam in the boiler is diminished, the
water is driven back in the boiler and out of the air chamber by the expansive
force of the air previously compressed. This is the principle according to which
the regulator or govenor works.
The weight E on the beam E being submitted to a certain pressure, the air
chamber H will remain above until the pressure in the boiler overrules this pressure;
but at that moment a sufficient quantity of water has been forced out of the boiler
into the said chamber to exceed the weight on the opposite end of the beam, and
consequently the whole of the flange c pushed on its knife edges and the air
chambers H descends the necessary distance.
The air chamber H and weight E¹, being connected by the rods h, h, in com-
munication with the valves, works the said valves, diminishing the heat in the
furnace, and consequently the pressure in the boiler. Then in proportion as the
pressure diminishes, the air chamber becomes lighter by the expansive force of the
compressed air pushing back the water, and then the apparatus resumes its
former position, turning the valves back, opening or closing them, as the case may
be. This machinery may be applied in any convenient way to regulate the pressure
of steam, either in the boiler itself or in any apparatus connected with the boiler, by
putting one arm or both arms of the apparatus in communication with the neces-
sary cocks or valves.
In witness whereof, I, the said Herbert John Haddan, have hereunto set my
hand and seal, this Thirtieth day of May, in the year of our Lord 1878.