IMPROVEMENTS IN MOTIVE-POWER ENGINES
Year: 1873

page_text: LETTERS PATENT to Johann Maximilian Plessner, of Golden Square,
in the County of Middlesex, late Captain in the Prussian Army,
for the Invention of "IMPROVEMENTS IN MOTIVE-POWER ENGINES"
PROVISIONAL SPECIFICATION left by the said Johann Maximilian
Plessner, at the Office of the Commissioners of Patents, with his
Petition, on the 3rd May 1873.
I, JOHANN MAXIMILIAN PLESSNER, of 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 MOTIVE-POWER ENGINES,"
to be as follows:-
This Invention relates to certain improvements in apparatus employed
for obtaining motive power from the pressure of the atmosphere.
I propose to apply one, two, or more cylinders open at one end to the
atmosphere, and provided at the other end with an aperture, which can
"

page_text: be closed by a slide, and serves for the admittance of a flash or flame
into the interior of the cylinder and below the piston.
To allow for the free escape of the air contained in the cylinder when
it is increased in volume through the action of heat I provide an orifice
generally in the wall of the cylinder (sometimes also in the piston) 5
which is closed by a slide. In the open end of the cylinder a piston is
fitted, which is connected with a crank of the driving shaft of the
engine. When the engine consists of two cylinders the shaft is doubly
cranked, the cranks standing in opposition to each other. If three
cylinders are used the shaft is three throwed, the cranks standing at 10
angles of one hundred and twenty degrees to each other.
The cylinders are made of cast metal, and are jacketed to receive
water from a supply tank to keep down the temperature.
The flashes or flames which are used to produce a partial vacuum
below the piston may be produced by lamps of various description, 15
deviating in their construction according to the nature and properties of
the fuel employed.
When burning hydrocarbons I generally use some sets of pipes for
the producing of a spray similar to the small apparatus known as the
perfume vaporiser. For this purpose I provide for each cylinder a small 20
air pump, the piston of which is in connection with a cam or other
mechanical contrivance attached to the crank shaft of the engine, and
for the ignition of the spray I generally use a small constant burning
flame in the immediate proximity of the pipes of the vaporiser.
When burning methylated spirit and such like liquid I use generally 2
a common spirit lamp, only on an enlarged scale, which is provided at
its upper surface with two slides moving towards and from each other,
an arrangement which allows the instantaneous producing of a very
large or a very small flame, according to the surface of the liquid or
saturated wick which the two slides cover or disengage.
For burning illuminating or other gas I generally use a common gas
burner provided with a cock, the handle of which is set in motion by a
cam attached to the crank shaft, an arrangement which also allows the
producing of flames or flashes of any desired dimension or duration.
The admission and escape valves of the cylinder are in connection 3
with each other, and will in general be moved by a cam on the driving
30

page_text: shaft of the engine; both valves will thus be opened and closed
simultaneously.
"
Besides the before mentioned two valves each cylinder is provided
with another small counterbalance valve serving for the escape of air
in case one cylinder is thrown out of gear or is worked with a very
small power, when the gaseous residue in the cylinder will become of
the same density as the outside atmosphere before the piston has accom-
plished its full working stroke, and the surplus volume of the gaseous
compound will be thus forced out by the motion of the piston.
From the above description it will be understood that the pistons will
act under atmospheric pressure only for half a stroke at the utmost,
corresponding to half a revolution of the crank shaft, which stroke may
be called the "working stroke," whilst the other half or return stroke.
must be accomplished by the power of the working stroke of another
piston or by the inertia of a fly wheel or its equivalent.
It is evident that in order to allow the return strokes to be accom-
plished without loss of power to the engine the slides of the cylinders
must be opened for the free access of the air, which is effected by the
motion of the same cam with which they are in connection.
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 3rd November 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHANN
MAXIMILIAN PLESSNER, of Golden Square, in the County of Middlesex,
late Captain in the Prussian Army, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Third day of May, in the year of our
Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Johann Maximilian Plessner, Her
special licence that I, the said Johann Maximilian Plessner, my exe-
cutors, administrators, and assigns, or such others as I, the said Johann
Maximilian Plessner, my executors, administrators, and assigns, should

page_text: 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 MOTIVE-POWER ENGINES," upon the con- 5
dition (amongst others) that I, the said Johann Maximilian Plessner,
my executors or administrators, by an instrument in writing under
my, or their, or one of their hands and seals, should particularly
describo 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 1
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 1
in and by the following statement, reference being had to the Drawing
hereunto annexed, and to the letters and figures marked thereon (that is
to say):
This Invention relates to certain improvements on the Invention for
which I obtained Letters Patent bearing date April Sixth One thousand 2
eight hundred and sixty-eight, No. 1156, consisting of apparatus for
obtaining motive power from the pressure of the atmosphere.
The defects of the various contrivances which I originally used
arose, first, from indirect application of the flames for rarefying the air
alternately on opposite sides of the piston; and secondly, from a faulty 2
construction of the cylinders and flame generating apparatus as well as
the mode of obtaining and applying the flame when used directly in a
cylinder on both sides of the piston, from which resulted an insufficient
vacuum, irregularity of action, waste of fuel, and occasional explosions.
I now propose to employ two or more cylinders open at one end to 3
the atmosphere, and provided at or near the other end with an aperture,
which can be closed by a slide, and serves for the admittance of a flash
or flame into the interior of the cylinder and below the piston.
To allow for the free escape of the air contained in the cylinder, when
it is increased in volume through the action of heat, I provide an orifice 3
in the wall of the cylinder, which is closed by a slide. In the open end
of the cylinder a piston is fitted, which is connected with a crank of the

page_text: driving shaft of the engine. When the engine consists of two cylinders
the shaft is doubly cranked, the cranks standing in opposition to each
other. If three cylinders are used the shaft is three-throwed, the
cranks standing at angles of one hundred and twenty degrees to each
other.
The cylinders are made of cast metal, and are jacketed to receive
water from a supply tank to keep down the temperature.
.
The flashes or flames which are used to produce a partial vacuum
below the piston may be produced by lamps of various descriptions,
deviating in their construction according to the nature and properties of
the fuel employed.
When burning methylated spirit and such like liquid I use generally
a common spirit lamp, only on an enlarged scale, which is provided at
its upper surface with a slide. This arrangement allows of the instan-
taneous production of a large flame.
For burning illuminating or other gas I may use a common gas
burner provided with a cock, the handle of which is set in motion by a
cam attached to the crank shaft, an arrangement which also allows the
producing of flames or flashes of any desired dimension or duration.
In the accompanying Drawing Fig. 1 shews. in sido elevation one of a
pair of engines intended to be connected together by a driving shaft,
and Fig. 2 is a sectional elevation of the same taken at right angles to
Fig. 1.
In the Figures A is the working cylinder open at top and partially
closed at bottom by a grid, fitted to and sliding under this grid is a
valve A³ with openings corresponding with those of the grid, and sur-
rounded by a water jacket A³. The cylinder is supported on pedestals,
and below it is fixed the lamp B. O is a piston connected by a link
rod C¹ to the crank D¹ of the driving shaft D. This piston is made cup
shaped for the reception of water, which will serve to keep down the
temperature of the piston. In the upper part of the cylinder A is a
_lateral opening E, which is covered by a slide valve E¹ similar in con-
struction to the slide valve A³ at the bottom of the cylinder. These
valves are connected together by means which I will now describe. F is
a rock shaft supported by brackets affixed to the top of the working
cylinder A. To this shaft is keyed a pair of arms F³, and jointed to

page_text: these arms by means of a rod F³ is a pair of links F³, to which the
slide E¹ is jointed. Pendent from the rod F is a link rod F, which is
jointed to a bell-crank lever Fs having its fulcrum at Fe on a bracket
projecting from the bottom of the working cylinder. A link F connects
the slide A² with the lower link of the crank lever F. By means there-
fore of this connection the two slides E' and A' will move simultaneously.
Motion is imparted to these slide valves through a compound counter-.
weighted lever F³, one end of which is furnished with a bowle to receive
the pressure of a cam G attached to the crank. plate D¹. The crank
plate D¹ also forms by an extension D³ on its periphery (see Fig. 2) a J
cam for giving a sudden action to a slide B³ of the lamp B, and thereby
opening the way for the exit of the flame. This motion is given the
slide B¹ by the cam D³ (in its rotation in the direction of the arrow)
striking the bowle of a bell-crank lever H, which lever is mounted on
the top of the working cylinder. Pendent from the lower limb of this
bell-crank lever is a rod H³, which is jointed to a second bell-crank
lever H* keyed to a rock shaft H³ mounted on the base plate of the
engine. A link H* connects this bell-crank lever with the lamp slide B¹,
and this slide is closed and held in a closed position (until the action of
the cam D on the bell-crank lever H is repeated) by means of a 1
counterweight lever Hs keyed to the rock shaft H³.
By reference to Fig. 2 it will be seen that the piston has just com-
pleted its up stroke and is about to descend, a partial vacuum having
been formed beneath it; the valves A¹ and E¹ are therefore closed to
maintain the exhaustion. As the piston descends, by reason of the
pressure of the atmosphere thereon, it will pull round the cam G, and
just before completing its downward stroke the cam G will come into
action on the lever Fs, and cause the depression of that lever to the
dotted position of Fig. 2. The effect of this movement of the lever F
will be to open the slides E¹ and A¹, the latter of which will admit air
to the cylinder A, and thus balance the atmospheric pressure on the
opposite sides of the piston; the rise of this piston will then take place
through its connection with the driving shaft, which is now being
actuated by the piston of the second cylinder assisted by the momentum
of the fly wheel I. So soon as the piston in rising reaches the port E
the cam D³ will begin to act, and the lamp slide being thereby opened
(the slides A¹ and B¹ being also open) a flame will rush into and fill the
cylinder A and immediately a vacuum is produced; all these slides will

page_text: be closed and the descending stroke of the piston will be repeated. To
enable the lamp to flash a flame into the cylinder A. immediately the
slide B¹ is opened I so construct the slide that in shutting off the lamp
it will leave a suitable number of wicks burning, which will serve to
ignite the adjacent wicks with the requisite rapidity.
Having now set forth the nature of my Invention of "Improvements
in Motive-power Engines," and explained the manner of carrying the
same into effect, I would remark that I do not claim the direct action
of the flame upon the air contained in the working cylinder however
that may be effected, but what I claim is, the peculiar arrangement of
parts above described constituting my improved engine, whereby a
vertical flame is flashed into the working cylinder and a vacuum or
partial vacuum is formed below the piston and maintained throughout
its working stroke.
In witness whereof, I, the said Johann Maximilian Plessner, have
hereunto set my hand and seal, the Third day of November,
in the woox of our Lord One thousand eight hundred and seventy.