Improvements in and relating to Steam Engines and Steam Generators.
Year: 1889

page_text: Date of Application, 24th Dec., 1889-Accepted, 1st Feb., 1890
COMPLETE SPECIFICATION.
Improvements in and relating to Steam Engines and Steam
Generators.
I, LÉON BÉNIER, of 39 Boulevard des Capucines, Paris, in the Republic of France,
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 a novel construction of steam engine and comprises the
improvements hereinafter described.
In the accompanying drawing
Figure 1 is a vertical section through the centre of the engine.
Figure 2.is a horizontal section.
Figure 3 is a vertical section of one of the parts of the boiler.
Figure 4 is an end view partly in section of the engine.
Figure 5 shews a vertical section and a horizontal section of a simple modification
of my construction of boiler.
Figure 6 is a vertical section of another modification of my construction of
boiler.
My improved engine has been designed with the object of obtaining with the aid
of steam a simple motor capable of working as easily as a gas or a hot air motor and
offering like the latter a practically absolute security. For this purpose it is
necessary to effect the vaporization under conditions such that the bursting of the
evaporating apparatus (and which it is impossible to absolutely prevent) will not cause
accidents.
When water is vaporized under pressure accidents arising from the vessel bursting
are the more serious the greater the quantity of water in ebullition. Thus it has been
computed that there are about 150 litres of water per square mètre of heated surface
in an ordinary boiler, while the volume is reduced to about 15 litres in a tubular
boiler. The latter volume is still much too great for it is sufficient to maintain a
very thin layer of water on a metal plate to absorb the heat transmitted by this
plate, the heat being given by the contact of gas and removed by a liquid. By
keeping on a surface of a square metre, only a millimetre of water, there would
not be more than a volume of one litre of water per square metre of heated surface.
and if, without extending the surface in contact with the water, the extent of heated
surface were quadrupled by the employment of ribs or projections there would only be
a quarter of a litre of water per square metre of heated surface. This result is obtained
in the apparatus hereinafter described.
The evaporating apparatus forming part of my improved motor is based on the
following combination; 1. Making the boiler of cast iron. 2. Causing the water to
arrive at the upper part of the boiler. 3. Making this water run in thin steams over
all or a part of the inside walls of the boiler, the water in excess passing to the lower
part of the boiler, whence it is removed. 4. Furnishing the surface of the boiler
exposed to the heated gases with ribs or projections similar to those employed in
heating apparatus. I would remark that in order that a boiler constructed on the
lines above described may work under favorable conditions it is not necessary for the
steam to be "sandwiched" between adjacent surfaces.
Figure 5 represents a type of boiler constructed according to this principle. It is
formed of a vertical cylinder a closed at each end the outer surface of which is
provided with ribs or projections. Water enters through the pipe b at the upper part
of the apparatus and runs in a small channel d arranged spirally on the inner side of
the cylinder. The steam which escapes in proportion as the water descends passes

page_text: freely into the cylinder a. The steam can be made to pass off through the pipe c,
placed at the lower part of the cylinder it then carries along with it the water which
has not been vaporised. If the steam is caused to pass off through the upper part of
the apparatus at s it is necessary to remove through the pipe c, by means of any
suitable mechanism, the water in excess which has not been vaporized. It is obvious
that the form or the arrangement of this type of boiler can be modified in various
ways. Figure 6 illustrates one of these modifications. The boiler is formed of several
small horizontal tubes f,f provided with ribs and communicating at one end with the
upper tube and at the other end with the lower tube so that water introduced through
the upper tube successively traverses all the tubes of the same vertical row, the exit
of the steam and of the water in excess taking place through the lower tube; the
small boss g limits the thickness more or less great of the stream of water which flows
in each tube.
Although slightly modified the boiler of my improved motor which I am about to
describe is constructed on this principle as shown in Figures 1, 2 and 3. This boiler
is placed within a cast iron frame H isolated from the hot gases and from the furnace
by a lining of refractory earth. The boiler is formed of four similar parts M, but
the number may be varied. Each part M is formed of cast iron provided on its
exterior with vertical ribs between which pass the heated gases from the furnace.
The parts M are provided with internal horizontal passages n, n, each passage com-
municating at one end with the passage immediately above it and at the other end
with the passage immediately below it so that on water passing into the upper part
through the pipe m, it traverses successively all the passages n and passes out through
the pipe t in the form of steam which pipe conveys it to a collector N.
fixed by bolts to each end of each part M allows of the conduits being inspected and
removed.
•
A door F
The small feed pump P continuously forces water into the boiler during the
working of the motor; its discharge is calculated so as to introduce the necessary
quantity of water to enable the required quantity of steam to be produced for keeping
the engine working at the normal speed, otherwise there would remain water in excess.
Further the supply of water introduced can in this case be decreased by any suitable
means. The water forced in by the pump passes through the pipe to a
collector o whence the small pipes m conduct it into the series of passages M, the
total section of the small pipes m being smaller than that of the pipe r; each series M
receives the same quantity of water.
Two safety valves can be provided as in ordinary boilers and a manometer can
also be supplied but is not indispensable as the level of the water is naturally
controlled.
The motor I am about to describe and which is specially constructed to be combined
with the boiler just described is arranged to receive in the cylinder a mixture of
water and steam and even salts carried along therewith. The cylinder is vertical and
open at its upper part. The piston is very long and forms a slide and is connected
directly by a connecting rod to the driving shaft which is carried in brackets cast
on the frame H. The distributing valves, that is to say, the inlet and outlet valves
are represented by two slide valves not enclosed in a box. The inlet openings and
especially the outlet opening should be placed at the lower part of the cylinder to
allow of the water introduced escaping easily. In some cases the two slide valves
may be replaced by two other valves. The speed can be regulated as in an
ordinary steam engine by a governor which operates a valve or other suitable regulating
device.
Having now particularly describod and ascertained the nature of my said
invention and in what manner the same is to be performed 1 declare that what
I claim is:
.
(1.) A boiler in which the water introduced at the upper part flows in thin
streams over the whole or a now of the L
1
1

page_text: provided with ribs the boiler being constructed of one or more series of tubes such
as M substantially as herein before described.
(2.) The combination of the boiler referred to in Claim 1 with the motor hereinbefore
described.
Dated the 24th day of December 1889.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.