IMPROVEMENTS IN OBTAINING MOTIVE POWER AND IN Apparatus to BE EMPLOYED FOR THIS PURPOSE
Year: 1871

page_text: LETTERS PATENT to Johann Maximilian Plessner, of Berlin, in the
Kingdom of Prussia, at present residing at 11, Golden Square, in
the County of Middlesex, late Captain in the Prussian Army, for
the Invention of " IMPROVEMENTS IN OBTAINING MOTIVE POWER AND IN
Apparatus to BE EMPLOYED FOR THIS PURPOSE."
Sealed the 26th March 1872, and dated the 30th September 1871.
PROVISIONAL SPECIFICATION left by the said Johann Maximilian
Plessner at the Office of the Commissioners of Patents, with his
Petition, on the 30th September 1871.
I, JOHANN MAXIMILIAN PLESSNER, of Berlin, in the Kingdom of
Prussia, at present residing at 11, Golden Square, in the County of
Middlesex, late Captain in the Prussian Army, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN OBTAINING MOTIVE

page_text: POWER AND IN APPARATUS TO BE EMPLOYED FOR THIS PURPOSE," to be as
follows:-
This Invention has for its object improvements in obtaining motive
power, and the improvements relate to obtaining motive power from the
explosion of gases.
In order to obtain a continuous motion from the explosion of gases
without subjecting the parts of the machinery to violent concussions as
heretofore I cause the gases to be exploded between two, pistons
working in a cylinder or cylinders; one piston is coupled to a crank on
the driving axis of the machine and the other piston has below it water
or other liquid. The diameter of the piston which has liquid below it
may be greater than of the piston which is coupled with the crank
shaft. When the gases are exploded the pistons are forced in opposite
directions, and the liquid forced back by the one piston is caused to
pass through a valve or valves into a chamber having at its upper
end an air space. As the water or liquid is forced into the chamber the
air in this space is highly compressed. After the piston which is
coupled with the crank axis has arrived at the end of its stroke an outlet
may be opened for the escape of the gases between the two pistons, or a
partial vacuum 'may be first formed by their condensation to allow of
the pressure of the atmosphere acting upon the piston for a portion of
the down stroke before the outlet for the gases is opened. The air
compressed as above described acting on the surface of the liquid then
forces it through a turbine or like engine and back through a valve or
valves into the space below the piston, to be again forced back by it on
the next explosion into the compressed air chamber. The axis of the
turbine is geared by suitable gearing with the driving axis, and thus
this axis is driven directly by the up stroke of the piston which is coupled
with it, and on the down stroke of this piston it is driven by means
of the turbine, and thus a continuous rotary motion is obtained without
shock. Two, three, or more of such engines may be arranged to work
with one crank or driving shaft to obtain a still greater uniformity of
motion. The supply of gases to be exploded is drawn into the space
between the two pistons at the time when the piston which is coupled
with the crank shaft commences its upward stroke, and when the desired
quantity of explosive gas has been drawn in and the communication
with the gas generator has been closed the gas is exploded by any
suitable means.

page_text: In some cases also in place of employing two pistons as above
described the piston resting on the water or liquid may be done away
with, and the gases be exploded between the surface of the water or
liquid and the piston which is coupled with the crank shaft, or the gases
may be exploded between the surface of water or liquid which acts
upon the piston coupled with the crank shaft and a piston having water
or liquid at the back, as before described:
I prefer to form the mixture of explosive gas by drawing up air
through liquid hydrocarbon, and for this purpose I employ a series of
pipes passing down through a stuffing box into a vessel in which the
explosive mixture is to be produced. The pipes are open at their upper
end and at their lower end dip into the liquid hydrocarbon at the bottom
of the vessel; when a quantity of explosive gas or vapour is drawn off
from the vessel air is drawn in through the pipes and it rises up through
the hydrocarbon liquid. The per-centage of hydrocarbon vapour taken
up by the air can be adjusted by causing the system of pipes to dip
more or less into the liquid hydrocarbon. Other known or ordinary
arrangements for obtaining a supply of explosive gas may however
be adopted.
d
Engines worked as above described by the explosion of a mixture of
air and hydrocarbon vapour may be employed either as fixed engines, or
locomotives, or for pumping water, and are especially applicable for ships.
on account of the great amount of space that will be saved not only by
the doing away with the ordinary steam boilers but also because the
liquid hydrocarbon will require a relatively smaller space for storing.
than is required for coal. The hydrocarbon may be stored in tanks.
forming part of the framework of the vessel, and may be drawn
off from the top of such tanks by allowing water to enter into them
at the bottom, so that such tanks will always be completely filled, and
there will be no vacant space at the top of the tanks in which vapour
might accumulate.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Johann Maximilian Plessner in the Great Seal
Patent Office on the 30th March 1872.
TO ALL TO WHOM THESE PRESENTS SHALL COME, JOHANN
MAXIMILIAN PLESSNER, of Berlin, in the Kingdom of Prussia, at present 5
residing at 11, Golden Square, in the County of Middlesex, late
Captain in the Prussian Army, send grecting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of September, in the year
of our Lord One thousand eight hundred and seventy-one, in the thirty- 1
fifth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto him, the said Johann Maximilian Plessner, Her special
licence, that I, the said Johann Maximilian Plessner, my executors,
administrators, and assigns, or such others as I, the said Johann
Maximilian Plèssner, my executors, administrators, and assigns, should 1
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 "IMPROVEMENTS IN OBTAINING MOTIVE POWER AND IN APPA- 2
RATUS TO BE EMPLOYED FOR THIS PURPOSE," upon the condition (amongst
others) that he, the said Johann Maximilian Plessner, his executors or
administrators, by an instrument in writing under his, 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 2
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 Johann Maximilian Plessner, 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 :-
This Invention has for its object obtaining motive power from the

page_text: Hitherto such combustion has generally been effected in a closed
cylinder on both sides of the piston, thus assigning to the explosive
gases the action of steam in spite of the great diversity of their
respective characters. This method must be considered imperfect
because, in the first place, a given quantity of a detonating substance
when exploded discharges its mechanical power suddenly and entirely,
while in the case of steam a constantly acting power is maintained either
by virtue of its elastic nature or in its connection with the boiler; and
because, in the second place, explosions of gases when thus executed on
a large scale would subject parts of the machinery to violent concussions
and ultimate destruction.
In order therefore to obtain the greatest possible amount of
mechanical labor from explosive combustion without injury to the
machinery it is necessary to resort to an intermediate and elastic agent,
which will permit, first, the storage of the greater part of the explosive
power, and then its conversion into mechanical labour as efficiently as is
the case with steam.
To realize this I prefer to cause the gases to explode between two
pistons working in a cylinder or cylinders; one of the pistons, called
the gas or vapour piston, being coupled to the crank of a revolving axis
whilst the other piston bears against a water surface. The force of the
explosion drives the two pistons in opposite directions, when one part of
the explosive power may be used for driving the gas piston from about
the middle to the end of its upward stroke, whilst the water with which
the water piston is in contact will be forced through a valve or valves
into a receiver provided at its upper end with an air chamber, wherein
the air will be compressed.
A partial vacuum being formed by condensation after the explosion
part of the down stroke of the gas piston will be effected under
atmospheric pressure, at the discontinuation of which an outlet must be
opened for the escape of the gaseous residua between the two pistons.
The return of the water from the receiver to its previous level in the
water cylinder generally takes place through the guides and buckets of
a turbine wheel, the axis of which I prefer to connect by suitable
gearing with the cranked axle to which the gas piston is attached.
The supply of gases to be exploded is drawn into the space between
the two pistons by the motion of the gas piston. As soon as the desired

page_text: quantity of explosive mixture or substance has been sucked up and the
communication with the gas supplier interrupted the explosion will be.
effected by the admittance of a light or by any other suitable means of
ignition.
The amount of power which each of the two pistons may receive from
the explosion can be divided to a nicety between both according to the
position of the crank to which the gas piston is attached at the moment
of ignition. The full power, for instance, of highly detonating sub-
stances may be directed exclusively towards the water piston when
exploding at the very moment the gas piston has reached the end of its
stroke, as this piston will then act like a fixed cover, the crank standing
at the dead point. In order to obtain a greater power as well as a
greater uniformity of motion two, three, or more sets of gas and water
cylinders may be applied for forcing water into a receiver and driving a
turbine or other water engine, in which case fly wheels may be dispensed
with.
"
From these general descriptions of an engine having for its prime
mover the explosive combustion of fulminating substances, and which in
accordance with its nature I denominate a "pyro-pneumatic engine,'
hereafter cited as "P. P.," it follows that in order to obtain a continuity
of the revolutions of its driving axis the water piston must arrive at the
end of its return stroke either earlier than the gas piston or at the same
time with it. To this end proper dimensions must be allowed as well
for the admission and escape water valves as also for the guides and
buckets of the turbine (if that hydraulic contrivance be used). Likewise,
suitable arrangements have to be devised for connecting the axis of the
turbine with the crank shaft of the engine should it be deemed desirable
to let the former revolve more quickly than the latter. Several
different methods for connecting the axis of the turbine (if used)
with the cranked axis of the engine will be seen hereafter from
illustrations of P. P. marine engines.
It is evident that the principle of pyro-pneumatics will hold good
quite independently of the nature of explosive substances as long as the
strength of the engine be sufficiently taken into account. Thus it
becomes possible to drive an engine by explosions of bydrocarbon vapours
mixed with atmospheric air, oxyhydrogen gas, gunpowder, or other
fulminating substances. And it is further obvious that those parts of
P. P. engines within which the explosion takes place must be modified

page_text: and adapted to the aggregate condition of the explosive fuel as, for
instance, by doing away with the gas cylinders and closing the water
cylinders with the exception of an opening through which the source
of power may act on the water piston.
Now, in order that my new P. P. apparatus and engines may be
clearly understood, I will proceed to explain them with reference to the
Figures in the accompanying Drawings.
Fig. 1 serves to illustrate the method for transforming the power of a
blow or falling weight into a rotary motion without injury to the
apparatus, and for measuring the mechanical labour contained in this
power.
(A) represents a wooden rammer inserted in a piston fitted in the
cylinder (B); (C) and (D) are two valves opening in opposite directions;
(E) is an air chamber; (F), a turbine; (G), a fly wheel, and (H) a weight.
A blow on the head of the rammer (A) will displace a certain quantity
of water by forcing it through the valve (C) into the air chamber (E),
thereby compressing the air within the latter. In reacting the air will
force back an equal quantity of water through the valve (D), whereby
this water must pass through the guides and buckets of the turbine (F),
thus causing the latter to revolve and to raise the weight (H), the fly
wheel (G) rather serving to embody the initial power of the air when at
its highest compression.
Fig. 2 shews a simple apparatus for measuring the mechanical.
equivalents contained in different detonating substances respectively for
transforming their violent power into a rotary motion, thus showing the
possibility of applying such substances as fuel for driving machinery.
Supposing a small quantity of fulminating substance be exploded in
the mortar (K) the explosion will drive the piston (A) upwards, and thus
force a quantity of the water contained in cylinder (B) through the
valve (C) into the air chamber (E), whence it will immediately return
by passing through the turbine (F) and the valve (D), causing the
turbine to revolve and consequently the weight (H) to be raised. It is
obvious that in order to permit the piston (A) fully to return an outlet
must be opened for the gaseous residua.

page_text: In Figs. 1 and 2 arrangements of winding on and off drums or pulleys
and appliances are shewn in order to obtain the required mechanical
effect.
Figs. 3 and 4 represent the section (3) and plan (4) of a P. P. stationary
engine with two sets of gas (V, V₁,) and water (W, W',) cylinders, and
one turbine (F) placed between the two sets, the axis of the turbine F
passing through the air chamber E, and being connected by means of
bevel wheel gear with a double cranked horizontal axis J, the extremities
thereof being provided with a fly wheel L and pulley M. The pistons
attached to the cranks moving in cylinders open at both extremities and 1
bolted at the top of the two water cylinders, the pistons of which, when
the engine is at rest are constantly kept at the upper extremity of the
cylinder by virtue of the tension of the air contained in the air chamber
before named. The gas cylinders are provided with three openings of
which N, O, and also N', O', are seen in the Drawing, Fig. 3, all of which 1
open and close by means of slide valves (not seen in the Drawings) driven
by cams attached to the crank axle. The first opening N (and N')
serves as entrance for the vapours or other gaseous substances; the
Becond O (and O') for the escape of the gaseous residua after the
explosive combustion; the third (which is not shown) for igniting a
purposes. The two water cylinders W and W' and the air chamber E
are bolted to a basin Bª filled with water, containing four valves C, D,
and C', D', and the turbine F, as shown on the Drawing.
The engine is set in motion by turning by hand the fly wheel, when
one of the gas pistons will draw up the explosive compound, and having
reached about half its upward stroke the first explosion will take place.
Part of the explosive power will drive the gas piston to the end of its
upstroke, whilst at the same time the water piston will be forced down-
wards, thereby forcing a certain quantity of water into the air chamber
E, thus compressing the air therein. (This position of the two pistons is a
represented in cylinders V, W³, of Fig. 3.) The crank axis J, J, will
now continue its revolution, firstly, in consequence of the downward
motion of the gas piston executed under pressure of the atmosphere, and,
secondly, in consequence of the rotation of the turbine F (caused by tho
return of the water from the air chamber E). The cranks standing in
opposition to one another the first explosion in the cylinder V will take
place, when the piston in the cylinder V has accomplished about half
its downward stroke, and thus a practically uniform rotary motion of the

page_text: turbine and cranked axis will be obtained. An eventual loss of water or
air may be restored by means of a small force pump. For the purpose
of keeping the metal of the gas cylinders V and Vat a moderate
temperature they should be enveloped by water, which can be done by
surrounding them with an outer case so as to provide space for the water
to be pumped in. This arrangement however, as also the position of
the cams and slide valves, is not shewn in the Drawings as not offering
any novelty.
As in the case of marine engines fly wheels cannot be applied, such
engines will be generally constructed with three sets of gas and water
cylinders besides the receiver and the turbine, and the respective
positions of these parts permits such a great variety of arrangement that
I shall confine myself to the description of a few typical constructions of
P.P. marine screw enginos.
Fig. (5 (section) and (Fig. 6 (plan) represent such a pyro-pneumatic
or gas marine screw engine; (V), (V'), (V³), are the three gas cylinders;
J, the three-throwed axis; E, the receiver; and F, the turbine.
Each of the three water cylinders, (one of which only (W¹) is to be
seen), communicates with the receiver E by means of large tubes Tu,
Tu', Tu', provided with valves C, C¹, C³, for permitting the water to
enter the receiver E but not to return the same way. In Fig. (5) these
water admission valves (C¹) of the centre system can be seen, as also the
valves (C) of the stern system. The receiver (E) is connected with the
turbine (F) by means of a large water tube (Wt) provided with a sluice
valve (Sv). The turbine wheel (F) is placed horizontally, and its axis
if prolonged falls in the same line with the axis of the screw propeller.
The water from the receiver after passing the sluice valve Sv, and the
turbine F, returns through the large tube (Rt) which communicates
with the admission tubes (Tu, Tu³, Tu³) by means of the balanced valves
(D), (D'), (D³). The axis of the turbine passes through stuffing boxes on
both sides of the tube (Rt) and is there coupled by connecting rods to
the three-throwed axis (J) through cranks standing at 90 degrees. It
follows from these arrangements that the screw, the turbine, and the
cranked axis make the same number of revolutions, and that for cach
revolution of the propeller three explosions will take place.
Figs. 7 and 8 show a somewhat different plan of arrangement, in
which the three gas and water cylinders and the three-throwed axis

page_text: are placed in the centre line of the vessel and consequently above the
turbine axes. The connection between the turbine axis and the three-
throwed axis is effected by gearing X, X, X', which arrangement
permits a greater number of revolutions of the turbine and the propeller
than of the crank axis J.
"
In Figs. 9 and 10 three sets of gas and water cylinders are placed
horizontally in order to diminish the height of the engine and to protect
it from shot and shell in war vessels. In this case the connection
between the cranked axis J and the screw Sa is effected by means
of cog and bevel gearing, as shewn in the Drawing at Figs. 9 and 10.
The other parts are similar to those shewn at Figs. 5 and 6, and are
marked with the same letters of reference. Each of the gas cylinders
is provided with four slide valves; the first serves for the admission of
the gaseous fuel, the second for the escape of the residua of combustion,
the third for the ignition, and the fourth for setting the engine in 1
motion. The former three are driven by cams attached to the crank
axis while the fourth can be moved only by hand.
For putting a marine engine in motion the gas cylinders must first
be filled with explosive vapours, and since these vapours will be
produced by the motion of the gas pistons themselves it is obvious
that a source of power must be held in reserve by means of which the
gas pistons can be put in motion independently of the explosive fuel.
To this end I provide a receptacle as part of every marine engine
wherein a source of power in form of compressed air is stowed. It is
fitted with a safety valve, pressure gauge, and starting valve, and a
large pipe, the lower end of which divides into three branches, each
leading to one of the gas cylinders. The compressed air may thus
be conducted between the gas and the water piston of one of the three
cylinder sets. An air pump which serves to fill the starting vessel
with air can be brought into connection with an excentric fixed to the
cranked axis, and thus this vessel may be replenished after having been
exhausted by starting the engine. The pump at the same time is
arranged so as to permit its being worked by a certain number of hands
in case of a ship lying at anchor and the starting vessel not being filled
with compressed air. In manoeuvring the ship it is however not required
to resort to the starting vessel, as the engine can work independently
of the propeller, which can be, disconnected and set in reverse motion

page_text: The
without stopping the engine, as will be herein-after shewn.
starting vessel only comes into use when the engine is entirely at rest.
The mode of starting the engine is as follows:-All the slide valves of
that gas cylinder the piston of which stands lowest whilst the inclination
of the crank is in the right direction are detached from their cams. The
slides of the admission and escape valves of the gas cylinder just named
have to be closed, when the valve of the starting vessel will be opened,
thus permitting the compressed' air to pass to the main pipe up to the
starting valve of the same cylinder. The slide of this valve will now
be opened, admitting the compressed air between the gas and water
pistons, whereby the former will move upwards the latter downwards
(as for instance in Figs. 5 and 7). In consequence of the descent of
the water piston the air in the receiver will to a certain degree be
compressed, and in order to utilize this compression the starting valve
must be closed when the gas piston reaches the highest point of its
stroke; at this moment the escape valve must be opened, thus per-
mitting the compressed air to escape from between the two pistons.
Then the compressed air in the receiver will expand itself, forcing the
quantity of water which previously entered by the descent of the water
piston back again through the turbine wheel, and thus causing the
latter to revolve. By this operation nearly one full revolution of the
cranked axis will be effected, and thus the two other gas pistons of the
two other gas cylinders will be set in motion and explosions obtained
which will cause the engine to work without further aid. The rods of the
admission and escape valves of the cylinder used for starting the engine
will then be connected again with their cams. The valve of the 'starting.
vessel will be closed and the air pump connected with its excentric until
the gauge indicates the refilling of the starting vessel with the proper
volume of compressed air. The axis of the propeller, which during the
progress of starting may have been disconnected from the engine, will
at this stage have to be joined again to it, and thus the ship will
commence its motion.
The connection between the axis of the turbine and the screw shaft
for the purpose of manoeuvring may be seen from Fig. (11). The end
of the turbine axis is provided with a friction cone (Co) behind which
a clutched disc (Di) revolving with the axis may be moved forwards
or backwards by the lever (Le). The end of the screw shaft is provided
with the disc (Sd) which can be moved by the lever (S Le) and

page_text: wherein the cone (Co) fits when the disc (Sd) is moved by the
lever (SL). The connection between the turbine and propeller may
thus be effected gradually by moving the clutched disc (Sd) towards
the cone (Co). When the pressure of the lever (SL) is sufficient to
make the screw revolve with the turbine a permanent connection can
be affected by joining both discs by means of the lever (Le).
For the purpose of reversing the turbine axis is provided, firstly,
with a cog wheel (Wh) having a friction cono attached to it and,
secondly, with a reversion friction cone (Co) revolving with the turbine
axis, and moveable by means of the reversing lever (RL). The screw
shaft is provided with a chain disc (Ch D). Above both is a short
reversing axis (RA), at one end of which is attached a cog wheel (Wh¹)
geared to the cog wheel (Wh). At the other extremity is a chain disc
(Ohd') connected to the chain disc (Chª) by means of an endless
chain (Ch).
In order to reverse the motion of the propeller the latter is first of
all disconnected from the turbine axis by means of the two levers (Le)
and (SL). Then the friction cone (R Co) is gradually brought into
contact with the cone of the cog wheel (Wh) by means of the reversing
lever (RL), when the screw will begin to revolve in an opposite direction
to the turbine axis.
The three levers (Le), (SL), and (RL) are set in motion by means
of powerful screws (S), (S'), (S³).
As not being part of my Invention I have not shewn how the method
of igniting the explosive vapours can be effected, which as is known
may be done either by means of an electric spark introduced into the
gas cylinder in the same way as the Lenoir engine, or by a light
introduced in the same way as in the Hugon gas engine.
In case hydrocarbon liquids aro used as fuel for P. P. engines, the
vaporisation of the liquid will not be effected by heat but by
mechanical means, the fuel being either used indirectly for wetting
canvas, cotton, or other like material through which the air will pass
and saturate itself before entering the cylinder, or it will be used
directly in the form of spray, in which case the air will pass through a
series of small pipes, to the upper end of which are attached other pipes a
dipping with their lower ends into the liquid fuel. The stream of air
passing through the former pipes causes the liquid in the other pipes to

page_text: engine, whereby rotary motion will be obtained and mechanical labour
effected.
In witness whereof, I, the said Johann Maximilian Plessner, have
hereunto set my hand and seal, this Twenty-eighth day of March,
in the year of our Lord One thousand eight hundred and seventy-
two.
Witness,
J. M. PLESSNER. (L.s.)
THOMAS MORGAN,
Secretary,
Inventors' Patent Right Association, Limited,
21, Cockspur Street.