Improvements in and relating to the Control of the Supply of Liquid or Vapour Fuel to Burners or Combustion Chambers of Steam Boilers or Pressure Generators using an Expansible Medium.
Year: 1899

page_text: Improvements in and relating to the Control of the Supply of Liquid
or Vapour Fuel to Burners or Combustion Chambers of Steam
Boilers or Pressure Generators using an Expansible Medium.
I, GEORGE ELI WHITNEY, of 32, New Street, Boston, State of Massachusetts,
United States of America, Inventor, do hereby declare the nature of this inven-
tion to be as follows:
The purpose of my invention is to control the supply of liquid or vapour fuel
to a burner or combustion chamber of a steam boiler or pressure generator
using an expansible medium.
To do this I make use of a diaphragm supported at its circumference or near
its outer edges in a closed casing in such a manner as to be perfectly tight and
to prevent any chance of leaking I place in the closed casing a spring holder
preferably in tubular form, which holder contains a spring, preferably a coiled
spring, one end of the spring holder is firmly attached to the diaphragm, while
the other end of the spring holder is substantially closed and so connected and
arranged as to receive and transmit to the diaphragm the strain caused by the
compression of the spring. The initial and practically permanent compression
of the spring is induced by a rod passing longitudinally through the spring and
having at the lower end thereof adjacent the diaphragm, a head or cap to take
the compression at that end of the spring, the other end of the rod passes first
through a hole in the closed end of the spring holder, and there being threaded
passes through a correspondingly threaded hole in the top end of the closed casing
above mentioned, by revolving the threaded rod it is obvious that I may place
a greater or less compression upon the spring within the spring holder, accord-
ing to the direction in which the rod is revolved, and this compression or strain
is transmitted through the spring holder to the diaphragm.
To the side of the diaphragm opposite the spring a rod is attached, said rod
carries a valve which governs the flow of the fuel to the burner, or if desired
such valve rod may be dispensed with and the valve attached directly to the
diaphragm, the valve seat or inlet for the fuel being brought correspondingly
near, or the diaphragm may itself form the valve and be pushed directly against
the fuel inlet or withdrawn from it, thus opening and closing the passage for
the fuel.
The side of the closed casing which contains the spring is connected with the
steam or pressure generator by a pipe or other suitable means, so that the pres-
sure of the pressure generator may be transmitted to the inside of the casing
and the diaphragm, the spring being set at a predetermined pressure by the
proper manipulation of the threaded rod as above described and so as to hold
the valve open then when the pressure of the expansible medium in the pres-
sure generator, and consequently on the diaphragm is sufficient to further com-
press the spring, the diaphragm is pushed downwardly against the force of the

page_text: through a hole in the closed end of the spring holder and there being threaded
passes through a correspondingly threaded hole in the top end of the closed casing
above mentioned, by revolving this threaded rod it is obvious that I may place
a greater or less compression upon the spring within the spring holder, accord-
ing to the direction in which the rod is revolved, and this compression or strain
is transmitted through the spring holder to the diaphragm.
To the side of the diaphragm opposite the spring a rod is attached, said rod
carries a valve which governs the flow of fuel to the burner or if desired
such valve rod may be dispensed with and the valve attached directly to the
diaphragm, the valve seat or inlet for the fuel being brought correspondingly
near, or the diaphragm may itself form the valve and be pushed directly against
the fuel inlet or withdrawn from it, thus opening and closing the passage for
the fuel.
The side of the closed casing which contains the spring is connected with the
steam or pressure generator by a pipe or other suitable means so that the pres-
sure of the pressure generator may be transmitted to the inside of the case
and the diaphragm, the spring being set at a predetermined pressure by the
proper manipulation of the threaded rod as above described and so as to hold
the valve open then when the pressure of the expansible medium in the pres-
sure generator and consequently on the diaphragm is sufficient to further com-
press the spring the diaphragm is pushed downwardly against the force of the
spring the valve above mentioned is closed and the supply of fuel shut off from
the burner.
A
When on the other hand, the pressure in the generator and consequently in
the connected closed casing, falls sufficiently, the strength of the spring exceeds
such pressure in the closed casing and consequently on the diaphragm, the dia-
phragm is drawn upwardly, the valve opened and the supply of fuel let on.
small flame from fuel coming through an independent pipe is kept constantly
burning on the combustion chamber or burner and this serves to light and re-
light the main burners as the supply of fuel is let on by the governing valve as
above described.
It has been found in practice that dirt or foreign particles are likely to lodge
between the valve and the valve seat of the fuel inlet rendering it impossible for
the action of the diaphragm as aforesaid to wholly close the valve. in order to
easily remove such particles I make the valve seat, the valve or a washer between
them preferably the valve seat, so that it may be readily oscillated manually
by means of a rod or handle for by this means any particles obstructing the
seating of the valve may be easily and quickly disposed of. In the manner
above described I provide an automatic regulator for the fuel of great reliability
and one that may be easily and readily kept in working order.
I also do away with all stuffing boxes which always create friction and gener-
ally leak, moreover if a stuffing box is used the valve actuating rod or any rod
passing through it is likely to become more or less stuck in the stuffing box.
I am also by the above described device enabled to keep the spring away from
the hot gas or liquid fuel which is likely to weaken or soften the spring.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a longitudinal section of the device for automatically regulating the
fuel feed to the burners which heat the boiler, the operation of the said device
being made dependent upon variations of pressure in the boiler.
Fig. 2 is a like section of the same device with which are combined; first,
means for cleansing the valve through which the fuel is supplied to the burners,
and, second, a mechanism for so regulating the device that it shall automatically
maintain, in the boiler, a predetermined pressure, variable at will.
Fig. 3 is a partial section of a like device, modified with reference to the
mechanism. shown in Fig. 2.

page_text: the tension thereof to be varied at will, instead of the arrangement shown in
Fig. 1, wherein the adjustment is effected by a nut 18. The said mechanism
comprises a lever 15 jointed at 15b to a link 15°, and connected to the rod 15*
jointed at 15b to a link 15°, and connected to the rod 15, the joint being, in this
instance secured by a stuffing box 15. The lever 15 is provided with a
handle 15 carrying a spring finger 15 cooperating with notches formed in a
sector 15 which may for instance, be graduated into atmospheres.
The operation is as follows. Assuming the lever 15 to be placed, for instance,
in position 7, the apparatus will be set for regulating the fuel feed so as to main-
tain in the boiler, a constant pressure of 7 kilogrammes per square centimetre,
say atmospheres or about 100 pounds to the square inch.
Figure 3 shows a modification of the mechanism shown in Fig. 2.
Here the mechanism is likewise composed of a handle 15° applied to an arm 15ª
fastened to an axis 15 carrying an eccentric 15' which actuates the rod 15; the
sector 15 is likewise graduated, as in the first instance.
I wish it to be understood that I do not limit myself to either of these mech-
anisms which have only been illustrated as instances.
Finally, from the fuel pipe c' leads a pipe 22 for supplying a pet burner which
is constantly burning with a small flame in the close vicinity of the boiler burners
proper, and which serves to light the latter, if needed, in the event of their
becoming extinguished in consequence of the gaseous fuel being abruptly cut
off.
From the boiler, not shown, a pipe leads to and opens into the case 1 on
the same side of the diaphragm as the spring and cylinder are located, the
boiler pressure thus acting on the diaphragm in opposition to the action of the
spring.
By moving the rod 15 in or out of the case 1 the tension of the spring is
varied, to adjust it to the desired degree of boiler pressure, and when such pres-
sure passes beyond that point the tension of the spring is overcome, and the
valve 12 is more or less closed, to decrease the supply of fuel to the injectors,
and thereby decrease the heat of the burner.
When the boiler pressure is reduced below the desired point the spring
operates to open the valve 12 and admit more fuel to the injectors, to thereby
increase the heating effect of the burner.
Whether the valve 12 is open or closed, however, the passage of the fuel to
the torch in the burner through the independent pipe 22 is not interfered with
or varied in the least, so that when the supply of fuel is cut off entirely from
the burner the torch is still operative.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:-
1. In an apparatus of the class described, a fuel vapor inlet, a controlling
valve for said inlet, and means to operate the valve, said means comprising a
case, having a flexible diaphragm therein and to which the valve stem or the
valve itself is connected, a spring in the casing having a fixed, adjustable sup-
port for its inner end, adjacent the diaphragm, a rigid connection between its
outer end and the valve or valve stem, the spring normally tending to maintain
the valve open, and a fluid pressure inlet for the casing, on the spring side of
the diaphragm, to move the latter in opposition to the spring and tending to
close the valve.
2. In an apparatus of the class described, a distributing chamber, a fuel vapor
inlet, a controlling valve for said inlet, and means to operate the valve, said
means comprising a case having a flexible diaphragm therein and to which the
valve stem is connected, a spring in the casing having a fixed, adjustable support
for its inner end, adjacent the diaphragm, a rigid connection between its outer
end and the valve stem, the spring normally tending to maintain the valve open,