IMPROVEMENTS IN STEAM-ENGINES
Year: 1885

page_text: I, WILHELM SCHMIDT of Brunswick in Germany, Engineer, do hereby declare
the nature of said invention for IMPROVEMENTS IN STEAM-ENGINES to be as
follows:-
In the suction-blast steam-engine shown in the accompanying drawing, Figs I
and II, high pressure steam is employed, which, on its way to the machine, acts
like an injector on gases of lower pressure, absorbs and compresses them, and the
mixture of the two then comes into action in the cylinder of the engine.
This method of combining and mixing two gases with each other and utilising
the mixture as a motive power is characterised by the action of a gas in a high
state of tension on a gas of lower tension by suction-blasts without condensation
of the bigh-pressure gas.
This method must by no means be confounded with the well-known employment
of injectors as a motor in which the blast gas is condensed and the principal part
is played by the differences of temperature, and not by the pressure of the gases.
The advantages of the present method are the following: In the steam-generator
but little water or steam is used, since a great number of active dynamical units
are added by high-pressure to the steam developed; this pressure is lessened by
the injector apparatus, and by mixing with low-pressure gas, so as to obtain a state
of tension suitable for use; the gas is increased in volume, and at the same time
superheated, and, thus, a large volume of gas is obtained with a small consumption
of water or steam in the boiler.
The suction-blast apparatus g. acts by the momentum of the high-pressure steam
leaving the tube , sucks up the gas from the tube ¹, and thus operates the
compression and partial superheating of the absorbed gas, without any condensation
of the high-pressure gas taking place; in fact, it only acts by its momentum.
A loss of force takes place in each steam-injector; this loss of force is transformed
into heat, which is communicated to the gaseous mixture, and superheating is the
result.
Fig. 1. shows the application of this improvement to a compound engine.
A. is the small cylinder; B. the large cylinder;. C. O is the receiver divided into
two parts, as a double employment of the momentum or mechanical energy is aimed
at by a double arrangement of injectors.

page_text: The high-pressure steam issuing from the tube r. absorbs in the injector
apparatus g. the steam of lower pressure from the part C₁ of the receiver, and, in
the steam-injector apparatus g¹ it compresses and superheats the steam from the
upper part of the receiver, pressing it into the receiver D, from which it reaches
the small cylinder.
When the steam in the small cylinder is spent, it enters the receiver, where it
partly returns into the suction-current or cycle, and is partly utilised in the large
cylinder B.
Of course, the steam issuing from B. can be condensed in the injector-apparatus
and again brought into circulation.
The arrangement of the suction-blast apparatus can, of course, be applied to
machines having several cylinders. In Fig. 2 is shown the application of this
method to an ordinary steam-engine.
By the dotted outline of the tube 11 is also shown that atmospheric air can be
sucked up direct by the suction-blast apparatus.
The machine then becomes a combined hot-air and steam engine.
Fig II shows also that the several injector-appliances or suction nozzles can be
separated by partitions and the suction-passages controlled by check-valves, so that
any desired number of suction-nozzles may be set in action.

page_text: COMPLETE SPECIFICATION,
I, WILHELM SCHMIDT of Brunswick in Germany, Engineer, do hereby declare
the nature of my invention for IMPROVEMENTS IN STEAM-ENGINES, and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :—
The improved steam engine illustrated by Figs I and II of the annexed drawings
(sheet 2) employs high-pressure vapours which on their way to the engine act by
suction on gases (which term is hereinafter intended to include vapours) of lower
but successively increasing pressure, so as to draw in and compress the same,
whereupon the gaseous mixture thus obtained is allowed to act in the cylinder
of the steam engine.
The characteristic feature of this method of combining and mixing gases with
each other for the purpose of utilising the mixture as a motive fluid, consists in
the repeated action of a gas at high pressure upon gases of lower, but increasing,
pressure by means of injectors or suction blast apparatus.
The result of every suction is a mixture of intermediate pressure, therefore a
reduction of the high pressure of the gas forming the blast.
I am aware, that suction blasts have been previously employed for drawing
in vapours of low pressure, and that a series of such blasts have been arranged in
succession.
Hitherto, however, this operation has always been performed by exposing the
gaseous mixture, produced by the first suction blast, to a fresh suction blast (of
high pressure), that is to say, by weakening the first suction blast which has for
its object to produce a gaseous mixture of intermediate pressure.
The only correct method, and that which has been adopted in the present case,
consists in causing the gaseous mixture resulting from the action of the first
suction blast, (which mixture has an intermediate pressure and is not adapted to
suck
gases of so low a pressure as that of the gas which has just been sucked) to
act in the form of a suction blast on fresh gases (which must have a pressure
higher than that of the gases sucked in by the first suction blast, but lower than
that of the gaseous mixture) thereby further reducing the average pressure of the
first gaseous mixture and utilizing the kinetic energy, still contained in the first
mixture, for sucking in fresh gases.
That is to say, whereas the methods hitherto adopted first employ a suction
blast to produce a gaseous mixture, and then use this mixture in the second blast
apparatus as the gas to be sucked, the principal feature of my present invention
consists in again utilizing this gaseous mixture as an active blast. The gaseous
mixture already in motion is not first allowed to come to rest, but the kinetic
energy contained in the mixture is utilised for a further suction of gas, until the
said energy is exhausted.
It is this arrangement of suction blast apparatus and the action of the gaseous
mixture as a suction blast on fresh gases of increasing pressures, which leads to
a complete utilization of the kinetic energy of the original blast, the greatest
reduction of the terminal pressure, and the greatest increase of volume, which is

page_text: the final object, because a blast may be exhausted as regards its sucking effect
on a gas of low pressure, while it is still capable of sucking gases of relatively
higher pressure.
Fig 1 of the drawing supplied with the provisional specification shows the
application of this improvement to a compound engine. A is the small cylinder;
B the large cylinder; OC¹ is the intermediate receiver or exhaust chamber divided
into two compartments by a horizontal partition.
The high pressure steam issuing from the tuber absorbs in the injector
apparatus g steam of lower pressure from the part C¹ of the receiver, and in the
injector apparatus g' it draws steam from the upper part C of the receiver or
exhaust chamber, pressing it into the receiver or mixing chamber D, from which
it reaches the small cylinder A.
The steam, having performed work in the small cylinder, enters the receiver C, C³,
where it partly returns 'into the suction current or cycle, while another part is
utilised in the large cylinder B.
Fig 2 of the same drawing shows the application of this method to a single
cylinder steam engine, which discharges the steam from the cylinder A into an
exhaust-chamber E connected with the suction pipe r¹.
The dotted outline of the tube 111 indicates, that instead of exhaust steam
atmospheric air can be drawn in by the suction-blast apparatus g¹.
The machine then becomes a combined hot air and steam engine. The same
Fig 2 also shows that the several suction nozzles can be separated by partitions,
and the suction-passages leading from the tube to the different compartments or
nozzle chambers may be controlled by check-valves, which prevent a return flow, so
that any desired number of suction nozzles may be set in action.
Fig I of sheet 2 shows another example of the application of my invention to
compound engines. As in the previous example, the receiver (N N¹) is divided into
two compartments which contain steam of different pressures, because the two sides
of the small cylinder work with different rates of expansion, which difference of
pressure is employed for utilizing step by step the kinetic energy of the steam
blast.
The exhaust chamber or receiver (M M³) supplied from the low pressure cylinder
in Fig I, sheet 2, is likewise divided into two compartments containing steam of
different pressures, and the whole arrangement works as follows:
The injector apparatus r operated by high-pressure steam from the boiler, draws
steam from the receiver M which has the lowest pressure among the 4 receivers
employed in this engine.
The mixture consisting of the said blast and the gas sucked in by the same, is
now itself utilized as a blast in the injector-apparatus by causing it to act by
suction on the receiver M¹ which contains steam of higher pressure, than the
receiver M. Although the gaseous mixture produced in the first suction apparatus r
is exhausted as regards its capacity of sucking steam at the pressure existing in the
receiver M. The kinetic energy lost by the blast by the mixture during this
process is partly utilized for the compression of the vapour drawn.in.
This second gaseous mixture now acts in the injector-apparatus ³ on the steam
contained in the receiver N, which has a pressure higher than than in the
receiver M¹, so as to suck steam from the receiver N, the gaseous mixture thus
produced now acts by suction in the injector-apparatus on the steam contained
in the receiver N₁ which has a pressure still higher than that of the receiver N.
It is evident, that in this manner a part of the steam used in the engine is
reintroduced into the series of operations and is, so to say, regenerated.
Consequently, little water is consumed in the boiler, and this method of gradual
suction affords a means of using steam at a pressure of two atmospheres or higher,
and of reducing this pressure while simultaneously increasing the volume of the
steam.
This gradual suction may, of course be extended to any convenient degree, and
atmospheric air may be used as the gas to be sucked in the first instance.

page_text: With this modification two stages of suction may be obtained even in the case of
a compound-engine having a single receiver (without subdivision into compart-
ments) as illustrated by Fig II, when R represents the air inlet and R¹ the inlet for
steam from the receiver. In a similar manner. air may be sucked, where several
receivers are employed.
Fig III of sheet 2 represents again a single cylinder engine with injector-
apparatus adapted to suck exhaust steam from the exhaust-chamber o, or atmo-
spheric air through the pipe p.
The injector or suction-apparatus has three successive nozzles q³ q³ and q³ each of
which is placed in a separate chamber communicating with the main suction-pipe R
through a separate branch pipe 71, 72 or 3 and each branch pipe contains a check
valve s¹, 8ª or 8³ adapted to prevent a return flow from the injector apparatus into
the suction pipe. This arrangement of injector-apparatus has for its object to call
into action only as many of the steam nozzles as are necessary, to exhaust the
kinetic energy or suction power of the blast.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1) The method of utilizing the kinetic energy of flowing gases, which consists in
first causing such gases to act as a suction blast on a gas of low pressure and then
causing the mixed blast of intermediate pressure resulting from such suction to act
again by suction on gases having a pressure higher than that of the gas first drawn
in, thereby applying the gradually decreasing velocity of the original blast or gas-
current, for the compression of gases of lower but gradually increasing pressure.
2) The application of this method to compound-engines, by causing the blast to
act by suction on several receivers, or on one receiver after having sucked atmo-
spheric air.
3) A multiple suction-blast apparatus, divided by partitions into several suction
or nozzle-chain bers communicating with the suction pipe or conduit by means of
check valves adapted to be closed by a pressure on the back of the valve,
DAL! 10th — ST100K