IMPROVEMENTS IN APPARATUS FOR USE IN THE MANUFACTURE OF ILLUMINATING GAS OR VAPOR
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by William Robert Lake at the Office
. of the Commissioners of Patents on the 16th May 1883. Communicated to
him from abroad by Edward, J, Frost of Philadelphia, Pennsylvania, United
States of America,
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, and Co. Patent Agents,
Southampton Buildings, London, "IMPROVEMENTS IN APPARATUS FOR USE IN
THE MANUFACTURE OF ILLUMINATING GAS OR VAPOR," [a communication to me
from abroad by Edward, J, Frost of Philadelphia, Pennsylvania, United States of
America,]
The said improvements belong to that class of carbureters in which the air
current is compelled to travel through a continuous and uniform passage, usually
of a spiral form, in which course it takes up a volatile hydro-carbon from the
surface of capillary material. According to a previous invention the communicator of
this invention has formed the walls of these spiral passages of capillary material, and
the arrangement was such as to isolate the air passage from the body of liquid which
directly supplied it. This feature is highly desirable and it is one of the objects
of the present Invention to still further ensure the isolation of the air current from
any free or unsuspended liquid and to reduce to a minimum the actual amount of
free liquid in the apparatus.
The present invention has for its further object the control of the density and
richness of the vapor, so that variations in its illuminating power and other effects
due to irregular evaporation can be avoided.
To these ends, this invention consists primarily in forming the carbureter with
a spiral air passage provided throughout at uniform short intervals with strands or
capillary material whose ends are immersed in the liquid to be evaporated, the air
passage being entirely isolated from the said liquid.
My invention also consists in providing the exit pipe of the apparatus with a
mixing jet, whereby air can be forced into the already charged current, so as to
dilute it to any desired extent.
My invention further consists in a device for automatically regulating the quality
of the illuminating vapor, and is to be used in connection with the carbureter
above described, or others.
•

page_text: According to the first part of the said invention I provide a reservoir for the
oil or volitile liquid to be evaporated, preferably the hydro-carbon known as
gasoline. This reservoir is air-tight and communicates by a pipe, controlled by a
cock, with a closed tank, the orifice of the pipe being preferably a very short
distance, say from 1/4 to 1/2 inch above the bottom of the tank. Within the tank 5
is an evaporating chamber consisting of top and bottom plates connected by a
spirally coiled sheet, the joint of this sheet with top and bottom plate being tight.
This spiral sheet may be made of wood veneering, or of any suitable rigid
material; the arrangement howeyer being such as to leave a practically continuous
and uniform air passage. At short intervals throughout the line of the spiral passage, 1
holes are formed in the top and bottom plates, and strands of capillary material,
preferable lamp wicking, are drawn through these holes and across the entire depth
of the chamber, the free ends of the strands extending into the space between the
bottom plate and the bottom of the outer tank. The holes in the bottom plate
are of such size as to be tightly closed by the wicking so that no liquid can enter
the evaporating chamber, except such as is drawn up by the capillary action.
The wicking is so passed through the holes as to form loops between two
adjacent holes at the top, while the lower ends are free.
At the centre of the tank is an air inlet pipe controlled by a cock and having a
nozzle which extends within the evaporating chamber, while near the periphery of
the tank, and adjacent to the open outer end of the spiral air passages, is the
exit pipe.
The exit pipe is provided with an enlarged chamber which communicates with
the air inlet pipe by a branch pipe having a regulating valve. Into this enlarged
chamber is inserted a discharge pipe, opposite the exit pipe referred to; this
discharge pipe is connected with the burner.
The operation of the apparatus is as follows; the liquid flows from the reservoir
into the bottom of the outer tank by means of a pipe extending nearly to the
bottom until the level reaches the bottom of this pipe, when, as the reservoir and
its pipe are air tight, no more can escape until the capillary action of the wicking.
takes up the liquid, thus tending to lower the level. The feed thus maintains
itself automatically until the wicking is all charged, and as the level of the liquid
is below the bottom plate of the spiral evaporating chamber no liquid can enter it.
Moreover the holes in the bottom plate of the spiral evaporating chamber are
closed by the tightly fitting strands, against any accidental entrance of liquid due
to agitation, or otherwise.
The blast being then turned on, the air current traverses the spiral passage
and is compelled to pass in close contact with each of the charged strands so that
it is saturated with the vapor, after which it is discharged at the exit pipe. If the
vapor is too rich, as is frequently the case, the cock on the pipe connecting the
mixing chamber with the air pipe is opened and the air blast rushes into the
mixing chamber, diluting the vapor by the admixture of air.
Whilst this regulation is valuable in connection with the described mode of
working the apparatus, it is specially so when another method of use is employed
for which the carbureter is, by reason of its peculiar construction, adapted. The
great length of the air passage and the capacity for very close and uniform
arrangement of the strands affords a mass of capillary material, which, in
proportion to the bulk of the apparatus, is comparatively very great, and thus a
large amount of liquid can be held in suspension. For example, I have arranged
in a chamber of two feet diameter, two thousand wicks, each composed of twelve
strands of ball wicking, nine and one half inches long, and by thoroughly saturating
these, have succeeded in supplying six three foot burners continuously for twenty
hours, after cutting off all feed. This capacity of the. apparatus for running so
long a time without any feed, is of great value, since it not only has the
advantages of a "dry carbureter due to the isolation of the air passage as
explained in the previous invention referred to, but dispenses with the necessity
»
.

page_text: of any reservoir of liquid either within the machine, or in its vicinity and thus
avoids the danger which always attends the pressure of these liquids in a free or
unsuspended form.
In railway carriages or upon ships, where the carbureter is exposed to agitation,
my improved apparatus can be used with entire safety, and moreover, the
irregularity in the light which would otherwise be occasioned by the splashing,
about of the liquid, is entirely obviated.
As before stated, it is in connection with this use of my improved evaporating
chamber that the diluting and mixing jet is of special value, for the vapor is most
highly charged, at the commencement of the operation, and diminishes in richness
as the saturation of the capillary material is reduced by evaporation so that but
for some means of regulating the richness of the vapor, the light would vary.
A little care in the adjustment of the cock, between the pipe in the air blast, con-
necting the air blast with the mixing chamber, will enable the operator to preserve
practical uniformity in the saturation of the vapor, but I also contemplate the use,
in this connection, of an automatic regulator, which will form the subject of a
separate application.
I am aware that it is not new to use a spiral chamber in connection with capillary
material suspended therein, but so far as I am aware in such cases the air passage
has not been isolated from the free liquid which supplied the capillary material.
It is obvious, moreover, that the exact form of the air passage above described
need not be used, and although I deem a regular and uniform spiral best adapted
to the desired result, I do not limit myself to any particular form, provided a
practically uniform and continuous air passage be formed of closely approximating
surfaces. Nor do I limit myself to the use of the regulating jet in connection
with an air evaporator of the type described, since it can be advantageously
employed with other forms of carbureters.
In the practical use of carburetting apparatus, it is. found that the degree of
saturation of the current varies from time to time, and thus produces irregularities
in the flame. thus for some time after the commencement of the operation of the
carbureter the current is apt to be too highly charged with vapor, and a dull flame,
of but little illuminating power is in consequence produced; even after the
apparatus has been running steadily for some time; accidental causes may occasion
a similar result, so that it has been found advantageous to provide a means for
diluting the charged current by admixture of air. For this purpose the blast pipe
of the apparatus has been connected by a branch pipe with the exit pipe leading
from the carbureter so that air could be forced into the vapor. So far as I am
aware, however, the admission of air for this purpose has not been automatically,
controlled, and the present invention is designed to accomplish that end. In the
use of such vapors as that of gasoline for instance, the variations in weight of the
vapor which correspond to these inequalities of illuminating power, are so
considerable that they may be used for effecting the movements of the regulating
valve.
According to the second part of this invention I combine with the exit pipe of
the carbureter, a barometric device, which moves in correspondence with changes
in density of the charged current, as a valve actuated by the movement of the
barometric device and an air inlet controlled by said valve. I also provide this
automatic regulator with a secondary barometric device so arranged as to com-
pensate for atmospheric effects which might injuriously affect the working of the
regulator. The only condition essential to the working of the apparatus is the
existence of a column of vapor of such height above the barometric devices as
that the changes in relative weight of the column shall occasion change of pressure
thereon sufficient to move the valve; and therefore the shorter the column the
greater must be the delicacy of the barometric regulator. As these carbureters,,
when used for domestic purposes, are generally placed below the level of the ground,
whilst the pipes extend to the upper part of the house, a column of vapor of more

page_text: than the necessary height is thus afforded, and the movements of the valve are
easily effected.
The second part of my device may be more particularly described as follows.
A pipe from the carbureters enters an air-tight box, on the opposite of which is
an exit pipe leading to the burners. A rigid diaphragm divides this box into two
compartments, one of which forms a continuous passage between the pipe leading
from the carbureter and the pipe leading to the burners.
The other compartment communicates, by means of a pipe, with the inlet or air
blast pipe of the carbureter, at a point before the entry into the evaporating tank.
• Communication between these two compartments is controlled by means of a
sliding valve, which. I prefer to construct of the form commonly known as grid-
iron so that a passage of large area may be uncovered by a slight movement.
-
Each compartment contains an aneroid box or plate constructed in the usual
manner; these I will call one and two.
One of these aneroid boxes is connected by means of intermediate levers with
the sliding valve, and the other is connected in a like manner to the valve seat
which is also movable.
As the aneroids face each other it will be seen that when both are depressed by
simultaneous increase of pressure in both compartments, the valve and seat will be
moved in the same direction; the movement of aneroid No 2 being reversed by a
suitable arrangement of levers.
One aneroid is capable of a minute adjustment, being mounted upon a stem
passing through the outer walls of the apparatus and provided with jam nuts; the
other aneroid need not be adjustable.
The operation of the device is as follows;-the adjustable aneroid is set, by
means of its adjusting screw, in its proper position.
This depends npon the amount of positive pressure excited by the blower of the
carbureter, and also upon the character of the vapor which is to be produced;
which conditions must be ascertained by actual test.
The adjustable aneroid is then so set that when in operation the valve shall just
cover the parts of the valve seat.
The air blast being then turned on through the carbureter the charged vapor
enters the gas compartment of the box and passes out at the pipe which leads
upwards to the burners.
So long as the density of the vapor of the blast remains normal, the valve does
not move, but should the gas become too highly charged the weight of the column
in the service pipe increases and the pressure upon the aneroid depresses its
diaphragm, thus moving the valve and uncovering more or less of the parts
according to this increase in density. The air pipe being in communication with
the inlet pipe of the carbureters, receives the full force of the blast undiminished in
velocity by the friction of the evaporating surfaces, and consequently when the
parts of the valve seat are uncovered by the movement of the valve, the air rushes
into the first or air compartment with a velocity slightly greater than that of the
charged current.
The direction of the two currents being; however, the same; they mingle freely
and without interference so that the charged current is diluted and its density
gradually decreased, when the pressure upon the aneroid in the gas compartment
being diminished, it moves outward and the valve again closes the parts.
Thus an automatic control of the degree of saturation is established more or less
minute according to the sensitiveness of the aneroid in the gas compartment. The
purpose of the second aneroid in the air compartment is as follows.
The actual atmospheric pressure being of course a factor in determining the
position of the aneroid in the gas compartment, variations due to the changes in the
condition of the atmosphere might disarrange the seat of the valve, and require
corresponding adjustments of the aneroid in the gas compartment, toward or away
from, the valve seat. The secondary aneroid in the air compartment acts to

page_text: compensate these variations and remove this element of inequality, as it moves
simultaneously with such movements of the aneroid in the gas or first compart-
ment, and as its motion is reversed by means of levers, the sliding valve seat is
moved by changes of atmospheric pressure to exactly the same extent and in the
same direction as is the valve, so that their relative positions remain unaltered.
It is to be observed, however, that the employment of the secondary aneroid is
not absolutely essential, since the same result could be effected by setting the first
aneroid, in the gas compartment from time so time to correspond with the changed
conditions, but I consider its use a valuable adjunct in that it renders the
regulation automatic in the highest degree.
It is obvious that the details of construction and arrangement can be varied
greatly without affecting the principle and mode of operation of the devices.