Improvements in and relating to Steam-generators, chiefly designed for Self-propelled Vehicles.
Year: 1896

page_text: Date of Application, 17th June, 1896
Complete Specification Left, 8th Mar., 1897-Accepted, 15th May, 1897
PROVISIONAL SPECIFICATION.
Improvements in and relating to Steam-generators, chiefly designed
for Self-propelled Vehicles.
I, EDOUARD EMPAIN, of No. 95 Rue de l'Enseignement, Brussels, in the Kingdom
of Belgium, Civil Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to steam-generators chiefly designed for self-propelled
vehicles.
In order that my said invention may be clearly understood, I have illustrated the
same, by way of example, in the accompanying drawings.
The improved steam-generator is composed of two distinct parts; the boiler
proper A, shewn on Figures 1, 2, 5, 6, 9, and a hot water and steam reservoir, B, B',
shewn on Figures 7 and 8; the reservoir B being tested to resist very high pressures.
Instead of a single reservoir B, B', several of these may be used, thus reducing the
thickness of the plates.
Water is brought from the reservoir B to the boiler A by means of a pipe C, and
being heated by the fire-box, rises successively through the tubes numbered 1 to 49,
which are all connected together; tube 1 to tube 2, tube 2 to tube 3, and so on up to
tube 49; these tubes are equally tested to resist very high pressures.
The water having circulated through the 49 tubes, becomes heated, and passes from
tube 49, through pipe D into the reservoir B. The deposited mud may be washed
out by opening the cock B, which is placed at the lower part of the reservoir B.
This reservoir now contains hot water and steam at a certain pressure. In order to
increase this pressure and in order to dry the steam, a pipe E and a cock H connect
the steam-chamber of the reservoir B with the tubes numbered 50 to 104 which I call
"revolver" tubes, and which are heated by the fire in the fire-box. These tubes are
shown in transverse section in Figure 11 and are connected with each other, as will be
seen from inspection of the drawings.
The steam passing through these superheated revolver-tubes, is dried and
superheated, and this dry and superheated steam is carried to the cylinders of the
engine, by means of the pipe F preferably provided with a regulating valve or
cock G.
If, when the vehicle is on a gradient and it is required to develope more power than
can be given by the steam in the reservoir B, which steam has been superheated and
dried by its passage through the revolver-tubes 50 to 104, then the cock H will be
shut, and after opening the cocks I' and K', hot water under pressure will be injected
from the reservoir B into the revolver-tubes 49 to 104, by means of the pump J,
which is worked by the engine or otherwise; this water, on entering the revolver-
tubes, increases the pressure on the steam, which may reach 367 lbs. per square inch
and upwards. Again if extra power is required only for a short time, after the
cock H has been shut, a small pump worked by hand may be used, taking water from
the reservoir B and forcing it into the revolver-tubes 50 to 104.
If the engine is stopped, as at the end of the line, or when the vehicle is going
down an incline, or if for any other reason no steam is required for working the
pistons, the revolver-tubes may be prevented from getting red-hot, and the heat of the
fire-box utilised by opening the cocks N' and Q', when the water from the reservoir B

page_text: will immediately flow into the revolver-tubes through the pipe N, will get heated, and
after rising through all the tubes from 50 to 104, it will return through the pipe O to
the reservoir B and increase the steam-pressure therein (see Figures 5 and 7).
The above mentioned revolver tubes may be manufactured of cast-steel, or they
may be made by drilling small holes in a bar of iron, steel or other metal, by the
process used in the manufacture of "Flobert" carabine barrels, or by any other
convenient process. The tubes as well as the holes, may be round, or have any other
shape. In order to lessen the section of the holes, and to roll the steam, so to say, an
iron rod of a smaller diameter may be introduced into each hole. This special
arrangement permits of the steam being dried to such a degree as to render it
invisible. The particular form of these tubes gives them great strength, prevents
them from being put out of shape, and even allows of water being injected into them
when red-hot, (see Figure 11).
These revolver-tubes may also serve to constitute a boiler by themselves. If the
pipes 1 to 49, which constitute the casing of the fire-box and of the boiler, are left
out, and if the casing of the boiler be made with fire-bricks, themselves cased with
sheet-iron, there will no longer be a duplex boiler, but a simple boiler, which will be
altogether inexplosible. To make it work, water is injected with a hand-pump into
the revolver-tubes 50 to 104; the engine being once started the pump J will work,
, and go on
pumping cold water which it takes from a tank W and injects into the
revolver-tubes. This arrangement makes a boiler which is absolutely inexplosible,
because the regulator G, being useless, is dispensed with, consequently there is never
any steam in the boiler when the engine is not working. In order to stop, it is
sufficient to interrupt the working of the pump, and if the boiler is in use on a
self-propelled vehicle, to put on the brake at the same time.
These revolver-tubes are applicable to a great number of arrangements and
applications, both for producing steam, for drying it, or drying certain other
gases.
The hot water and steam reservoir B, which is an intrinsical part of the boiler,
is fed by means of an injector, which takes its cold water from the tank W, shewn
in Figures 3 and 4.
The dry steam after having done its work in the cylinders, is discharged into
an exhaust box, forming part of the fire-box, and from there into the fire-box
itself, where the exhaust steam may be decomposed into oxygen and hydrogen, so
as to utilize this latter gas for heating the boiler. The arrangement for this
purpose is as follows.
The steam, after having done its work in the cylinders, is carried through the
exhaust-pipes R into the exhaust-box S, S', S", S where it comes into contact
.with the red-hot plates of the fire-box, and where it is partly decomposed, to
escape into the fire-box and the boiler through the opening Z, Z, Z, Z,
In a further decomposition of the steam is desired in order to separate the
hydrogen, and burn this bydrogen in the fire-box, then a stream of hot air is
injected through a tuyere T, this hot air being taken from the box U, U₁, U", U
which encloses all the tube connctions. The blast of hot air from the tuyere T
on the incandescent coke of the fire-box, draws on to the coke the whole of the
exhaust-steam, the latter passing through the opening Z, Z, Z, Z; the steam is
decomposed, hydrogen is set free and is burnt in the furnace, thus serving as fuel
(Figures 1 and 9).
Figure 10 shews a more special arrangement for decomposing and burning the
exhaust steam. The exhaust-pipes are placed at R R', and open into the exhaust-
box S, S', S", S. The steam goes all around the inside of the exhaust-box, and
being in contact with the red-hot plates of the fire-box, is partly decomposed;
then entering the fire-box through the opening Y, Y, Y", "Y", it comes into
contact with the incandescent coke, the steam is more completely decomposed, and
the hydrogen is set free. In order to burn this hydrogen and keep up the
combustion of the coke, the tuyere T blows into the fire-box hot air, taken from
the box Ụ, U, U", U in which are the tube connexions (Figures 9 and 10),

page_text: The arrangement of the casing tubes, as well as that of the revolver-tubes is
liable to a great number of various arrangements. For instance, the tubes 1 to 8
(Figure 5), may be dispensed with, and the fire-box surrounded by fire-bricks or
other refractory materials, all other tubes being maintained. In this case the pipe C),
would be connection to tube 9.
In some cases, and considering the profiles of some lines, there would be no
harm in doing away altogether with the casing tubes, and using in their stead a
refractory or other casing, keeping only the pipes 10 to 20 in order to heat the
reservoir B permanently (see Figures 12, 13, 14); all the other arrangements of
pipes, cocks etc., being maintained and keeping the same functions.
tubes 1 to 9 and 21 to 49 may also be replaced by casings made each. out of a.
single piece of cast steel or other metal, and provided with sets of holes to allow
the circulation of the water, as shown on Figure 5.
The
These tube casings may also be replaced by casings made of sheet metal and
provided with cross-ties made of shaped bars. These shaped bars are each
interrupted at one end, so as to form a regular channel, through which the water can
circulate in the same way, as it does in the tubes (see Figures 15 and 16).
Dated this 17th day of June 1896.
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London; W.C., Agents for the Applicant.
Improvements in and relating to Steam-generators, chiefly designed
for Self-propelled Vehicles.
I, EDOUARD EMPAIN, of 95 Rue de l'Enseignement, Bruxelles, in the Kingdom of
Belgium, Civil Engineer, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained in
and by the following statement:-
This invention relates to steam-generators chiefly designed for self-propelled
vehicles.
In the accompanying drawings
Figure 1 is a front view of the boiler with the door of the fire-box removed;
Figure 2 is a plan of the same;
Figures 3 and 4 shew the cold water-receptacle, respectively in plan and cross-
section;
Figure 5 is a horizontal section on the broken line A'-A', Figure 1;
Figure 6 is a horizontal section through the twyer T, Figure 1.
Figure 7 is a vertical section of the part A of the boiler, in which the steam is
produced, this section being taken in a plane parallel to the front view, Figure 1;
Figure 8 is a horizontal section on the line AA, Figure 7.
Figures 9 and 10 are respectively a vertical and a horizontal section through a
modified construction of the hot-water and steam reservoir, showing a single reservoir,
instead of two as in Figures 1 and 2;
Figure 11 is another vertical section of the steam producing part but in a plane
perpendicular to the one, in which Figure 7 is situated;
Figure 12 is a front view of the lower part of Figure 1, with alterations of some
details;
Figure 13 is a vertical section through the twyer T in Figure 12;
Figures 14 to 18 shew different constructions of some parts of the boiler, which
may be altered according to circumstances, without departing from the nature of
the said invention;

page_text: Figure 19 is a cross-section through one of the steam-drying and superheating
..tubes, numbered 50 to 104 in Eigura. 7...
Figures 20 to 31 are cross-sections and partial longitudinal sections through
modified constructions of these same tubes, the bores thereof having been narrowed
by different devices.
This boiler is composed of two distinct parts;
1. The boiler proper A, shewn in Figures 1, 2, 5, 7, 8 and 11, and composed of a
set of tubes, numbered from 1 to 49 in Figure 7, and tested to resist very high
pressure. All these tubes communicate together through connections, and their
arrangement will be easily understood by referring to the respective figures.
Above the tubes 10 to 20, and filling up the whole of the empty space above them,
is another set of tubes, numbered 50 to 104 in Figure 7, which I call "revolver
tubes" on account of their section, which resembles that of a revolver barrel (see
Figure 19); the construction and the use of these tubes will be more fully explained
hereafter. These tubes are also connected with each other by connections, which will
be seen in Figure 8.
2. A set of hot-water and steam-reservoirs B B¹, shewn in Figures 1 and 2, which,
are tested to resist very high pressures. Instead of a set of these reservoirs, a
single one may be used, as shewn in Figures 9, 10 and 16, but in that case the thick-
ness of the plates will have to be increased. A pipe connects the bottom of the
reservoirs or reservoir with the tube 1, and a pipe D connects it with the tube 49.
Another pipe N, having a cock N' connects these same reservoirs with the revolver
tube 50, while a pipe O, having a cock O', connects it with the revolver tube 104,
which is again connected through a pipe F, having the regulator G, with the cylinders
of the engine. The steam space of the reservoir or reservoirs is connected with the
revolver tube 50 by a pipe E having a cock H.
A pump J, placed underneath the reservoirs B, or beside them, is connected with
their bottom by a pipe I having a cock I', and it is also connected with the revolver
tube 50 by a pipe K having a cock K'.
The above mentioned revolver tubes, which serve to dry and superheat the steam,
may be manufactured of cast steel, or they may be made by drilling small holes in a
bar of iron, steel or any other metal, by the process used in the manufacture of
"Flobert" carabine barrels, or by any other convenient process. The tubes, as well as
the holes, may be round, or have any other convenient shape. In order to lessen the
section of the holes, and to better dry and superheat the steam, an iron rod, or a
piece of metallic cable, may be introduced into the holes, which are then less in number
and of a wider section; also a single hole may be bored in the centre of the bar, and
a single bar or cable be introduced into this hole. Several such modifications are
shewn in Figures 19 to 31 by way of example, but many other constructions may be
used. This special arrangement permits of the steam being dried to a degree
rendering it invisible. The particular shape of these tubes gives them great strength,
prevents their being put out of shape, and even allows of water being injected into
them when they are red-hot.
Having thus described the most essential parts of the new boiler, I shall now
explain how these different parts act together.
Water is brought from the reservoir or reservoirs B to the boiler A by means of the
pipe C, and being heated by the fire, rises successively through the tubes numbered 1
to 49, which, as has been said, are all connected together, tube 1 to tube 2, tube 2 to
tube 3 and so on, up to tube 49.
The water having circulated through the 49 tubes, becomes heated, and passes
from tube 49, through pipe D back into the reservoir or reservoirs B.
The
deposited mud may be washed out by opening the cock B, placed at the lower part
of the reservoirs B.
These reservoirs now contain hot water and steam at a certain pressure. In order to
increase this pressure and dry the steam, the cock H is opened, and the steam entering
tube 50 through pipe E passes through the whole set of revolver tubes, which are
heated by the fire of the fire-box, until it comes out at tube 104 to be carried to the

page_text: cylinders of the engine through the pipe F and the regulator G. By its passage
through the superheated revolver tubes, the steam is dried and superheated and its
pressure considerably increased.
If, when the vehicle is on a gradient, it is required to use more power than can be
given by the steam in the reservoirs B, superheated and dried by its passage through
the revolver tubes 50 to 104, then the cock H will be shut, and after opening the
cocks I and K', hot water under pressure will be injected from the reservoirs B into
the whole set of revolver tubes, by means of the pump J, which is worked by the
engine or otherwise; this water on entering the revolver tubes increases the pressure
of the steam, which may reach 365 lbs. per square inch and upwards. Again if extra
power is required only for a short time, the cock H having been shut, a small pump
(not shewn in the drawings) worked by hand may be used, taking water from the
reservoir and forcing it into the revolver-tubes 50 to 104.
If the engine is stopped, as at the end of the line or when the vehicle is going
down an incline, or if for any other reason no steam is required for working the
pistons, the revolver tubes may be prevented from getting red-hot, and the heat
from the fire-box utilised by opening the cocks N and O when the water from
the reservoirs B will immediately flow into the revolver-tubes through the pipe N,
will get heated, and after rising through all the tubes from 50 to 104, it will return
through the pipe O to the reservoirs B, and increase the steam pressure therein (see
Figures 1, 2 and 7).
These revolver tubes may also serve to constitute a boiler by themselves. If the
tubes 1 to 49 which constitute the casing of the boiler and of the fire-box, be left
out, and if the casing of the boiler be made with fire-bricks, themselves cased with
sheet-iron, there will no longer be a duplex-boiler, but a simple boiler, which will be
altogether inexplosible. To make it work, water is injected with a hand pump into
the revolver tubes 50 to 104; the engine being once started the pump J will work,
and go on pumping cold water, which it takes from the tank W (Figures 3 and 4) and
injects into the revolver tubes. This arrangement, makes a boiler which is absolutely
inexplosible, because there is never any steam in the boiler when the engine is not
working, and the regulator G, being useless, may be dispensed with. In order to
stop, it is sufficient to interrupt the working of the pump, eventually putting on the
brakes.
These revolver tubes are fit for a great number of arrangements and applications,
as well for producing steam, as for drying it, or drying certain other gases.
The hot water and steam reservoirs B are fed by means of an injector, not shewn
in the drawings, which takes its cold water from the tank W.
The dry steam after having done its work in the cylinders is discharged into an
exhaust box, forming part of the fire-box, and from there into the fire-box itself,
where the exhaust steam may be decomposed into oxygen and hydrogen, so as to
utilise this latter gas for heating the boiler. The arrangement for this purpose is
as follows:
The steam after having done its work in the cylinders, is carried through the
exhaust pipes R (see Figures 1 and 11) into the exhaust-box S, S', S", S, where it
comes into contact with the red-hot plates of the fire-box, and where it is partly
decomposed to escape into the fire-box through the opening Z, Z, Z", Z.
If a further decomposition of the steam is desired in order to separate the
hydrogen and burn this hydrogen in the fire-box, then a current of hot air is
injected through the tuyère T, this hot air being taken from the box U, U, U, U,
which encloses all the tube connections. The blast of hot air from the tuyère T
on the incandescent coke of the fire-box draws on the coke the whole of the exhaust
steam, the latter passing through the opening Z, Z', Z, Z; the steam is decom-
posed, hydrogen is set free and is burnt in the furnace thus serving as fuel.
Figures 12 and 13 shew a more special arrangement for decomposing the exhaust
steam. The exhaust pipes are placed at R R and open into the exhaust box S, S¹,
S", S. The steam goes all around inside of the exhaust box, and being in contact

page_text: with the red-hot plates of the fire-box is partly decomposed; then entering the
fire-box through the opening Y, Y, Y", Y, it comes into contact with the
incandescent coke, the steam is more completely decomposed and the hydrogen is
set free. In order to burn this hydrogen and keep up the combustion of the coke,
the tuyère T blows into the fire-box hot air, taken from the box U, U', U", U, in
which are the tube connections.
The arrangement of the casing tubes as well as that of the revolver tubes is liable
to a great number of various combinations. For instance the tubes 1 to 8 (see
Figure 7) may be dispensed with and the fire-box surrounded with fire-bricks or
other refractory materials, all other tubes being retained. In this case the pipe C
would be connected to tube 9.
In some cases and considering the profiles of some lines there would be no harm
in doing away altogether with the casing tubes, and using in their stead a refractory
or other casing, retaining only the tubes 10 to 20 in order to heat the reservoirs B
permanently (see Figures 14, 15 and 16), all other combinations of pipes, cocks, etc.
being retained and keeping the same functions. The tubes 1 to 9 and 21 to 49 may
also be replaced by casings made each out of a single piece of cast steel or other metal
and provided with sets of holes to allow the circulation of the water.
These tube casings may also be replaced by casings made of sheet metal, and
provided with cross-ties made of channel-shaped bars (see Figures 17 and 18).
These channel-shaped bars are each interrupted at one end, so as to form regular
channels, through which the water can circulate in the same way as it does in the
tubes.
my
Having now particularly described and ascertained the nature of said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A steam generator comprising a series of tubes or chambers forming both a
casing to the fire-box and to other parts of the boiler and a perforated screen
over the fire-box, a hot water and steam reservoir, pipe connections between said
tubes and said reservoir, and a series of rods or bars of comparatively large cross-
sectional area, each having several passages of small cross-sectional area, said rods or
bars being arranged above said perforated screen within the said casing, substantially
as herein before described and for the purpose specified.
a
2. A steam generator comprising a series of tubes forming perforated screen
across the combustion chamber of the boiler and a series of rods or bars of compara-
tively large cross-sectional area, each having several passages of small cross-sectional
area and arranged in the combustion chamber of the boiler, a steam and hot-water
reservoir and pipe connections between the several parts, substantially as, and for the
purpose, hereinbefore described.
3. In a steam generator, a series of rods or bars of comparatively large cross-
sectional area, each having either several passages of comparatively small cross-
sectional area directly bored into it, or having larger passages which are afterwards
narrowed by rods, metallic cables or the like being introduced into them, substantially
as, and for the purposes, herein before described.
4. The combination, in a steam generator, of metallic rods or bars of comparatively
large cross-sectional area each having longitudinal passages of comparatively small
cross-sectional area, with a pump or the like for forcing water through the passages of
said rods or bars, substantially as, and for the purposes, hereinbefore described.
5. The different arrangements of pipes and cocks E H, N N', O O', K K', II
enabling the driver at will to increase the pressure of steam in the tubes 50 to 104
either by opening the cocks and K' and using the pump J or a hand pump, or by
working with the pressure of the reservoirs B, or again in some cases to use all the
104 tubes for producing steam, substantially as, and for the purposes, herein before
described and shown in the drawings.
6. The combination, in a steam generator of a fire-box having a chamber around

page_text: the same to receive the exhaust-steam from a steam-engine, from which chamber the
said steam passes into the fire-box to mingle with the combustible matter therein,
substantially as, and for the purposes, hereinbefore described.
7. The combination, in a steam generator, of a fire-box having a chamber around the
same to receive the exhaust-steam from a steam-engine, from which chamber the said
steam passes into the fire-box to mingle with the combustible matter therein, and a
tuyère for injecting a supply of hot air into such fire-box, substantially as, and for
the purpose, herein before described.
Dated the 8th day of March 1807
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.