An Improved Method of and Apparatus for Obtaining Motive Power by Means of Explosions.
Year: 1894

page_text: Date of Application, 23rd May, 1894-Accepted, 15th Sept., 1894
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Obtaining Motive Power
by Means of Explosions.
I HERBERT JOHN HADDAN of the Firm of Herbert Haddan and Co., of
18 Buckingham Street, Strand, W.C. London, Patent Agent, do hereby declare
the nature of this invention, a communication to me from abroad by the Firm of
Piguet and Company, of 25 Rue de St. Cyr Lyons, in the Republic of France,
Engineers, and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement:-
The thermodynamic utilization of a source of heat is the function of the fall of
temperature due to the work done.
The small output of steam engines worked by a piston or a jet of vis-viva tends
to the working body only effecting an insignificant fall of temperature against the
temperature of the furnace which is considerable.
A good steam generator gives a useful effect of 70 per cent. of the heat source.
A good condensing steam engine worked by piston or jet and acting at the initial
pressure of 17 lbs., absolute, gives a useful effect of 15 per cent. of the heat of the
steam. The final output or utilization of the potential work in the combustible is
therefore only 0-70 × 0-15 = 0.105.
As the generator appears to have attained its maximum of utilization, it has been
sought again and again to raise this final output by all possible means, such as by
condensation to effect the elevation of the initial pressure, by super-heating, the
reduction of the volume of space, and lastly the diminution of the short thermic
circuit of active surface, and especially of the dead surface by means of the steam
jacket by divided or multiplied expansion as regards the nature of such surfaces,
of the reduction of their area, and of the increase of their speed, but by the aid of
such processes, the final output in question has never passed 0.15.
Struck by the inefficiency of these results, many engineers for a long time past
have directed their investigations towards the increase of the fall of temperature
realized by means of the elevation of the initial temperature of the working body,
but this elevation presents with vapour the inconvenience of a too rapid increase of
pressure, they seek to make use of gases and especially for avoiding the use of feed
apparatus and the loss of time therein; they have endeavoured to use detonating
bodies or mixtures as working media.
Unfortunately up to the present in explosive machines with metallic pistons, one
has been compelled, for effecting the actuation of the piston in the cylinder and
overcoming the resistance of the apparatus, to materially lower the pressure and
the maximum temperature disposable, thus only utilizing the energy under slight
tension or temperature, that is to say employing a very slight portion of the total
work of the explosive.
Knowing these difficulties or impediments and the importance of overcoming the
same, I have first sought to do away with the metallic piston as a recipient of
work, then for working under the greatest possible fall of temperature disposable
due to the combustion of a body, I find that it is essentially convenient to effect
such combustion rapidly, which avoids the loss of heat and other actions of time,
but without seeking to intentionally decrease the inaximum pressure and temperature
of the explosion, and lastly to transmit the vis-viva or total work due to the
explosion by allowing the products of such explosion to pass over any recipient,
the float board of a turbine for instance, directly or by the medium of a projectile
or gaseous or liquid piston thus increasing the mass in movement and reducing
the speed of flow.
Under the influence of these ideas, I have tried to make use of explosives such

page_text: as powders or fulminants, petroleum, essences or hydrocarbons liquid or gaseous,
hydrogen, carbonic oxide, etc., also directly of carbon from which certain hydro-
carbons and gas are artificially formed, that is to say, that instead of making
previously a troublesome artificial extraction of those hydrocarbons and gas,
effect the spontaneous combustion of pit-coal or charcoal in small quantities by
blowing it in an extremely pulverized state into the necessary volume of air and
obtain its combustion by means of a flame or any spark on enclosure of said
volume. Where the carbon is too poor in hydrocarbons, I previously impregnate
such hydrocarbon by a process which is effected by adding previously carburetted
air made according to requirement by blowing air over volatile hydrocarbons,
mineral spirits for instance.
Lastly the apparatus for realizing this method of action is of such slight weight
and requires such restricted amount of combustible that these advantages have
suggested to me the idea of applying the same for the purpose of navigation,
aerostation and aviation apart from other uses for which very naturally the properties
of a light, simple, and economical motor renders it fitted.
Referring to the drawing which is in the form of diagrams, Fig. 1 shows a vessel
of small capacity d into which is introduced at certain intervals a certain regulated
quantity of any suitable explosive, the gaseous mass resulting from the deflagration
of this explosive will have an enormous speed of flow through the nozzle e, the
vis-viva of the jet of this mass during its flow through the nozzle e can well be
utilized by passing the same directly onto any recipient for instance the bucket of
a turbine, but in order that the output of this recipient of the vis-viva be as
large as possible, it is necessary that the impacts of the jet be as feeble as possible,
that is to say that the movement of the recipient be near enough to that of the jet.
In using a rotary recipient such as the turbine I cannot attain an equal speed
without forcing it to mollecular deflagration. I therefore have to restrict the
speed of the recipient for its organic preservation and thus to sacrifice its output.
Instead of allowing the jet of the motor to arrive directly on the recipient I
compel the same as in Fig. 2 to communicate, under a sufficiently high output, its
vis-viva to any fluid gaseous or liquid; this mass acting as a kind of projectile or
fluid piston, will arrive on the recipient as a secondary jet, with a speed, the square
of which will be reduced in proportion as the mass of the secondary jet is
increased.
By this second means, I have therefore not only as in the first one, increased the
thermodynamic output due to temperature, and the considerable rapidity of the
explosion, but have reduced the speed of the secondary jet by carrying to
the recipient perceptibly the same amount of work. I can therefore without fear
of the impact of loss, give to the recipient a speed which is compatible with its
mollecular preservation and also a considerable and sufficient output.
By the two means illustrated in Figs. 1 and 2 I can transmit the work of the
explosion in two different ways; first, directly. by fixing the detonator or simply its
jet nozzle and leaving the recipient, which may be of any kind, movable and
secondly, inversely by fixing the recipient and leaving the detonator or simply the
nozzle of the jet motor movable.
This is the principle of working by a detonator with direct jet and secondary
jet with a gaseous or liquid mass.
As a mass for secondary jet I use any gaseous or liquid fluid for instance air or
water, regulated at will, which I introduce mechanically in any suitable way for
instance as shown in Fig. 3 by the aid of an injector with appropriate nozzle, so as
to laterally communicate to the secondary body the vis-viva of the exploded
products. This mass having its initial temperature much lower than that of the
explosion, averts not only the aforementioned increases of speed, which are hurtful
for the output, but also to a certain degree those increases of the temperature
burtful to the organic resistance of the detonator and to the play of its distributor,
capable of causing premature explosions.
The explosive body may likewise be of any kind, solid, liquid, or gaseous.

page_text: Certain kinds of these explosives are either dangerous in use or offer troublesome
difficulties in their natural or artificial production and although I may work with
anything suitable in this motive process, I make use especially of a natural
combustible which is most common and consequently to be had for a certain limited
price and which possesses the greatest possible accumulated energy, namely coal, or
more generally pit coal and even charcoal which, introduced in a pulverized state of
sufficient tenuity are capable of producing a spontaneous or explosive combustion.
If, in gas motors, it is desired to explode the gaseous products of coal, it is
necessary to previously distill the hydrocarbons or to produce hydrogen, carbonic
monoxide or other explosive gases. This process is obtained by the aid of a gas
producer and at the expense of the consumption of a certain quantity of fuel, which
inaterially decreases the final output of the thermodynamic process.
Instead of having recourse to this previous process, and of suffering the thermic
loss in the gas producer, as well as the costs of preparation, maintenance, manage-
ment &c., I reduce mechanically the pit coal or charcoal into an extremely fine
powder and in this state of tenuity blow it by a current of air, which at the same
time presents the corresponding volume for combustion into the detonator d or any
inflamatory chamber, for instance an electric one, which effects its explosion after
such detonator or chamber is closed. If the powdered carbon is found to be too
poor in hydrocarbons for producing a certain degree of explosion I previously
impregnate such powder with richer hydrocarbons such as petroleum, mineral
spirit etc. and then blow it into the detonator by the aid of a volume of air which,
if required, has previously been carburetted by passing over these hydrocarbons.
This particular method of employing the combustible not only avoids the use of
gas producers and steam generators as actually in use but also enables me to use
any combustible dust or powder gathered in mines, coal cellars, etc.
The powdered state of the carbon may be the object of special treatment before
its consumption but the motor itself can, as diagrammatically shown in Fig. 4
actuate the powderer or disintegrator d of the coal charged through the hopper t,
the bolting mill b and the ventilator v which passes the explosive mixture to the
detonator d actuating the receiving turbine r.
Whatever may be the nature of the combustible or explosive used, I make the
detonator sufficiently small, in order not to run the risk of a mollecular deflagration
under the maximum pressure and temperature of the explosion, multiplying the
number of detonations and the number of detonators for producing a given amount
of work in a certain time. Having not to fear, as in gas engines with metallic
piston the heating of the walling, which hinders the play of a moving part, or
injuring the mollecular resistance of the apparatus, I can therefore, just as in
fire-arms, approach the high pressures and temperatures and nevertheless
considerably increase the total fall of temperature of the working explosive body,
that is to say the economic output.
The distribution of the explosive body in the detonator is effected by the aid of
any suitable mechanism with continual or alternative movement, as for instance
that which is used in gas motors, which allows the quantity of explosive to
penetrate automatically by means of a regulator according to the resistance of the
charge. This regulation may be as well applied to the explosive matter as to
that of the injected gaseous or liquid projectile and to their sectional area of flow.
The ignition is effected by a flame or electric spark, as in the volta-pistol and in
gas-motors.
On the same receiver as the vis-viva, for instance the float board of a turbine, I
can make to act either one jet or a battery of jets (primary or secondary). On the
other hand each primary jet may be the issue of a single or of a battery of
detonators, and each secondary jet from a single or a battery of primary jets may
pass through a single or a battery of injectors of the fluid projectile matter.
The detonators of a battery may fire simultaneously, but it is preferable in order
to reduce the speed of the flow and to obtain a better output, to fire successively
and as rapidly as possible from one detonator to the other of the battery.

page_text: With the majority of explosives the detonator empties itself naturally of the
solid or fouling residuum and this residuum is carried off in solution by the body
of the primary jet and the secondary jet. But the detonators may be arranged on
a revolving barrel as in fire-arms (such as revolvers), whereby it is possible to use
only one distributor and where the combustible or explosive employed gives rise to
fouling, to have only one fire-chamber in action and a series of open ones into which
a strong liquid or gaseous jet for cooling and cleaning may be passed.
When the receiver of the vis-viva from the exploded products is a turbine of any
construction with axial centrifugal centripetal or lateral propulsion, the rotation of
its float-board takes place under the propulsive influence of the pyro-pneumatic field
of one or more jets, which makes of this motor a true dynamo pyro-pneumatic one,
just as the inductive influence of the magnetic field makes an electric-dynamo by
the rotation of the coils.
A number of turbines may be placed on the same shaft with float-boards and
jets rotating in the same direction but they may also be arranged in the contrary
sense toward each other if it is desired to effect a change in rotary direction.
When the receiver of the vis viva originating from the exploded products, which
then flow in the form of one or more primary or secondary jets, is the water in
which floats a boat or the air, in which flies any aerostatic or aeroptetic apparatus
carrying my light but powerful motor, I produce by the reaction upon the water
(in the former case) or upon the air (in the latter case) a method of propulsion and
direction with change in the course, which latter is very advantageous for the
navigation, aerostation and aviation, without making use of any intermediary
receiver and propeller in movement, thus relieving considerably the vehicle of
weight and diminishing the work of propulsion.
But this method of propulsion and direction, in the use of this sort of motion,
may also be obtained by the aid of the same motor with intermediary receiver, such
as a turbine acting as propeller.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The improved method and means for producing work by the aid of an explosive
motor, its characteristic feature being the transmission of the vis viva of the
elementary explosive products passed onto the float-board of a turbine or any
other receiver through a direct or secondary jet by the intermission of a projectile
or fluid piston (gaseous or liquid) added to and transmitted by the explosive jet so
as to first increase the output or useful effect of the receiver by reduction of speed
of the jet motor and also to avert increase of temperature, hurtful to the resistance
of the detonator and capable of causing premature explosions.
2. The said motor constructed in connection with any receiver especially with a
receiving turbine; with or without change in running direction; having any number
of float-boards or buckets on the same rotary shaft, with a single or a battery of
detonators or jets for maintaining a practically constant output by varying,
according to the charge, the amount of explosive and that of the injected gas or
liquid and their sectional area of flow.
3. In the said motor the employment as an initial explosive of pit-coal or
charcoal in pulverized condition, blown into the detonator by the volume of air-
natural or carburetted-which is necessary for its explosive combustion.
4. The transmission of the work of the detonator or of the jet by use of a fixed
nozzle acting on any movable receiver, or inversely by use of a moving detonator
reacting on any fixed receiver.
All substantially as and for the purpose set forth.