AN IMPROVED STEAM GENERATOR
Year: 1868

page_text: LETTERS PATENT to Pierre Joseph Ravel, of Paris; in the Empire of
France, Civil Engineer, for the Invention of AN IMPROVED STEAM
GENERATOR."
Sealed the 4th May 1869, and dated the 16th November 1868.
PROVISIONAL SPECIFICATION left by the said Pierre Joseph Ravel
at the Office of the Commissioners of Patents, with his Petition,
on the 16th November 1868.
I, PIERRE JOSEPH RAVEL, of Paris, in the Empire of France, Civil
Engineer, do hereby declare the nature of the said Invention for "AN
IMPROVED STEAM GENERATOR' to be as follows:-
This Invention consists in a new arrangement of steam generator with
rapid water circulation heated by petroleum by the aid of particular
apparatus, and applicable to all industrial purposes, but more especially
to steam locomotion on ordinary roads.
The boiler is composed of a single serpentine coil (preferably of
copper) communicating by its lower extremity with a double metallic
envelope, and by its upper end with a steam reservoir, formed by an
Price 8d.]

page_text: outer envelope of iron, steel, or copper. The water is fed in at the
lower part of the double envelope, by means of a feed pipe fills the same,
and then enters the serpentine coil at its lower end in which it rises and
escapes from its upper end in the form of steam into the steam reservoir
which surrounds the whole apparatus. The furnace is placed below the
serpentine, the coils of which are closed in such a manner as to form a
wall all round. The gases of combustion are compelled to pass upwards
through the cylindrical envelope thus formed, and then descend between
the exterior of the spiral and the interior of the double envelope, and
pass by a circular chamber (which surrounds the steam reservoir) to the
chimney.
In order to regulate the feed I employ a cylindrical vessel communi-
cating at its upper part with the steam reservoir, and at its lower part
with the serpentine coil by means of a pipe. In this reservoir is a float
which rises and falls with the level of the water (which is the same in
the vessel as in the coil) and causes a lever to open or close a valve in
connection with the feed pipe. By these means if the boiler has too
much water, the float rises and opens the valve, and allows the water to
escape and to return to the tank. If there is not too much water this
valve remains closed; and the feed continues as usual.
The apparatus for burning the oil is composed of several concentric
annular envelopes placed in a cylindrical box constantly filled with
petroleum or other mineral oil. In these spaces are placed wicks of
amianth or asbestos which dip into the oil, and the air passes between
them and also through a central hole. The quantity of air supplied, and
consequently the rapidity of the combustion, is regulated by opening or
closing more or less a valve or damper which is worked automatically by
the pressure of the steam. The admission of the petroleum to the
burner is also regulated in a similar manner.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of November, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
second year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Pierre Joseph Ravel, Her special licence
that I, the said Pierre Joseph Ravel, my executors, administrators, and
assigns, or such others as I, the said Pierre Joseph Ravel, my executors,
administrators, and assigns, should at any time agree with, and no others,
from time to time and at all times thereafter during the term therein
expressed, should and lawfully might make, use, exercise, and vend,
within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "AN IMPROVED STEAM
GENERATOR," upon the condition (amongst others) that I, the said Pierre
Joseph Ravel, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to
be filed in the Great Seal Patent Office within six calendar months next
and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Pierre Joseph Ravel, do hereby
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and
by the following statement in writing, and on reference being had to
the accompanying Sheet of Drawings, that is to say:-
This Invention consists in a new arrangement of steam generator
with rapid water circulation heated by petroleum or mineral oil by the
aid of particular apparatus and applicable to all industrial purposes, but
more especially to steam locomotion on ordinary roads.
The boiler is composed of a single serpentine coil (preferably of
copper) communicating by its lower extremity with a double metallic
envelope, and by its upper end with a steam reservoir, formed by an
outer envelope of iron; steel, or copper. The water is fed in at the lower
part of the double envelope, by means of a feed pipe fills the same, and
then enters the serpentine coil at its lower end, in which it rises and
escapes from its upper end in the form of steam into the steam reservoir
which surrounds the whole apparatus. The furnace is placed below the
serpentine, the coils of which are closed in such a manner as to form a

page_text: wall all round. The gases of combustion are compelled to pass upwards
through the cylindrical envelope thus formed, and then descend between
the exterior of the spiral and the interior of the double envelope, and
pass by a circular chamber (which surrounds the steam reservoir) to the
chimney.
In order to regulate the feed I employ a cylindrical vessel communi-
cating at its upper part with the steam reservoir, and at its lower part
with the serpentine coil by means of a pipe. In this reservoir is a float
which rises and falls with the level of the water (which is the same in
the vessel as in the coil) and causes a lever to open or close a valve in
connection with the feed pipe. By these means if the boiler has too
much water the float rises and opens the valve, and allows the water to
escape and return to the tank; if there is not too much water, this
valve remains closed, and the feed continues as usual.
The apparatus for burning the oil is composed of several concentric
annular envelopes placed in a cylindrical box constantly filled with
petroleum or other mineral oil. In these spaces are placed wicks of
amianth or asbestos, which dip into the oil, and the air passes between
them and also through a central hole. The quantity of air supplied, and
consequently the rapidity of the combustion, is regulated by opening or
closing more or less a valve or damper which is worked automatically
by the pressure of the steam. The admission of the petroleum to the
burner is also regulated in a similar manner.
"An
Such being the nature and object of my said Invention for
Improved Steam Generator," I will now proceed to describe more in
detail the manner in which the same is to be or or may be performed or
carried into practical effect, and in order that the same may be distinctly
understood I have annexed hereunto a Sheet of Drawings illustrative
thereof, and have marked the same with figures and letters of reference
corresponding with those in the following explanation thereof, that is
to say:
Figure 1 in the annexed Drawing is a vertical section of the improved
steam generator taken through the line 1-2 in Figure 3; Figure 2 is a
vertical section taken through the line 3-4 of the same Figure;
Figure 3 is a transverse section through the line 5-6 of Figures 1
and 2; Figure 4 is a vertical section of the apparatus for burning
the oil, and Figure: 5 is a plan view of the same.

page_text: The boiler is composed of a single serpentine coil A, A, (preferably of
copper tubing,) communicating by its lower extremity with a double
envelope B, B, and by its upper end with a steam reservoir C, C, formed
by the casing D, D. The water enters at the lower part of the double
envelope B, B, by the feed pipe E, E, and after filling it flows into the
lower end of the coil A, A, by the tube F, F, in which it rises, and
whence it passes in the form of steam by the tube G, G, into the steam
reservoir C, C, which surrounds the whole. The furnace H, H, is placed
beneath the serpentine tube, the coils of which are brought close
together, so that it forms as it were a wall. The gases evolved are
compelled to ascend through the cylindrical space thus formed, and then
to redescend between the exterior of the coils and the interior of the
double envelope B, B, to pass by the circular chamber I, I, which
surrounds the steam reservoir C, C, and escape by the chimney J, J.
The red arrows indicate the direction taken by the gases of combustion.
There results from this arrangement, firstly, that the water circulates
against the metallic surfaces in direct contact with the flames of the
furnace, and is converted into steam almost instantaneously; secondly,
that the steam passing into a space the walls of which are heated by the
hot water in the double envelope B, B, and by the gases of combustion
which surround it, before passing to the chimney becomes superheated
without the expenditure of any more fuel.
In order to regulate the feed I have designed the apparatus represented
in section at Figure 2, which consists of a cylindrical vessel K, K, com-
municating at its upper part with the steam reservoir G, G, and at its
lower part with the coiled pipe A, A, by means of the tube a, a. In this
vessel is a float L, L, which rises and falls with the level of the water
(which is the same in the coil as in the vessel K, K,) and raises or
lowers by means of the rod b, b, a lever c, c, which opens or closes a
valve M, M, communicating by a tube d, d, with the feed pipe F, F.
Thus if there is too much water in the boiler the float rises and opens
the valve M, giving passage to the feed water, which escapes and returns
to the tank. If on the other hand there is not sufficient water the
valve M remains closed, and the water flows into the boiler.
The oil burner H, H, shown in section at Figures 4 and 5 is composed
of several concentric annular envelopes e, e, placed. in a cylindrical
box f, f, constantly filled with petroleum or other mineral oil. In these

page_text: spaces e, e, are wicks of amianth or asbestos which dip into the oil,
and between these spaces the air can pass as well as through the
central hole g, g. The quantity of air supplied, and consequently the
intensity of the combustion of the oil, is regulated by opening (more or
less) the damper h, h, which is actuated automatically by the increasing
or decreasing pressure of the steam, by means of an apparatus N
(Figure 2) consisting of a cylindrical piston k, a second piston 1, and a
system of levers m, n, o, p, acting on the hinged damper h, h. The
under side of the piston k is in communication with the steam
reservoir G. The piston works in a box from the side of which branches
the oil supply pipe. When the pressure in the boiler is normal the
piston k is lowered, and the piston allows the petroleum to flow, but
if the pressure increases the piston k rises and lowers the piston / by
means of the lever m, and prevents the oil from flowing into the burner,
at the same time the levers n, o, p, move the damper h, h, against the
under side of the burner H, H, intercepting the air and extinguishing
the flame, so that the lowering of the pressure in the boiler becomes
facilitated.
This boiler gives a great quantity of steam for a very small volume,
it is very light and not liable to explosion, and may readily be applied
to a carriage for common roads, as shown in elevation at Figure 6, and
plan view Figure 7. M is the boiler, N the seat, which also serves as a
water tank, and contains the petroleum vessel O. P and P' are two
small oscillating or other steam engines driving the cranked axle Q, Q,
of the hind wheels R, R. S, S₁, are the front wheels mounted on a
turntable for guiding the carriage, and T, T', are the feed pumps.
Having now described the nature and object of my said Invention
for "An Improved Steam Generator," together with the manner in
which the same is to be or may be performed or carried into
practical effect, I would remark in conclusion that I claim as my
Invention,-
Firstly. The peculiar and novel arrangements of the boiler as shown
and herein-before described with its feed regulating apparatus.
Secondly. The special mode of heating by means of petroleum or
mineral oil together with the automatic means of regulating the com-
bustion.

page_text: And, thirdly. The special application thereof to steam locomotion on
ordinary roads, or to other similar purposes.
In witness whereof, I, the said Pierre Joseph Ravel, have here-
unto set my hand and seal, this Eighth day of May, in the
year of our Lord One thousand eight hundred and sixty-
nine.
P. J. RAVEL. (L.S.)