Improvements in Gas and like Engines.
Year: 1898

page_text: Improvements in Gas and like Engines.
We, HEINRICH HILDEBRAND, of 2, Pesenbachstrasse, WILHELM HILDEBRAND,
of 1A, Frauenhoferstrasse, and ALPHONS BRUCKMANN, of 5, Schönfeldstrasse, all
of Munich, in the Empire of Germany, Merchant, Engineer, and Austro-Hun-
garian Consul, respectively, do hereby declare the nature of this invention
to be as follows:-
This invention has for its object an improved valve for gas engines and is
characterized by the valve being arranged vertical and easily movable in a cham-
her entirely closed to the outside, in such a way that it is raised and opened by
the excess pressure from below and closed by its own weight or the excess of
pressure from above, with the object of producing a sure opening and closing of
the valve without the use of special controlling mechanism or springs, whilst
by altering the movement and weight of the valve the charges of the working
cylinder may be modified within certain limits to influence the mean number
of the revolutions of the motor.
The igniting device is assumed to be an incandescent tube lighter. Of course
in its place however any other suitable igniting device, such for instance as
an electric one, or the like, may be employed, without altering in any way the
other procedure or working of this machine.
The mode of working is as follows:-
In the cylinder space the gas drawn in by a previous stroke is suitably com-
pressed. After the ignition has taken place the piston moves a little and the
expansion of the ignited gas takes place which produces the working stroke.
The several valves are closed at the moment of the explosion. In certain arrange-
ments the back pressure valve may be omitted.
The piston in its further course (working stroke) passes over the discharge
line and then the discharge gases commence to emerge from the cylinder. The
valves are at this moment still closed whilst the discharge valve is already lifted
during the expansion movement of the piston in consequence of the condensa-
tion of the gas drawn in the space at the other side of the piston and the mixture
of gas is divided between the said constantly diminishing space and a pipe which
forms a kind of reservoir.
When the piston has completed its working stroke, the waste gases will have
escaped through the discharge openings and from the moment at which the
pressure in the first space has become smaller than the now increased pressure
in the other space and in the said pipe the valve will have risen in order to
allow a fresh mixture of gas to flow into the working cylinder driving any
remains of the consumed gas before it. The other valve is closed.
When the piston has commenced its return course (suction and compression
stroke) and has passed over the discharge line, the discharge valve will close

page_text: itself at once on the commencement of the return movement of the piston because
the pressure in the cylinder space is smaller than that in the pipe. When the
piston has traversed the course opportunity is afforded to the mixture of gases
stored up in the pipe under a certain excess pressure to reach or to flow into the
working cylinder. By this means the discharge valve is closed and the inlet
valve opened.
When the pressure in the said space and pipe has become equal or in other
words the piston has passed over the discharge line, the inlet valve will close
and the mixture of gas contained in the cylinder space be compressed. During
the entire return movement of the piston the other valve is opened in cruer to
again draw the mixture of gas from the suction pipe into the other space (suction
stroke). After the suction stroke is completed the first position is again attained
and the second ignition takes place. The operation is repeated at each revolution
of the crank shaft once so that a sure-acting two-stroke machine is produced.
The closing and opening of the discharge pipes by means of the piston influ-
ences according to the foregoing description the function of the inlet vaiv in
such a way that the piston may be described to a certain extent as the regulating
means for the inlet valve. The valve can only lift when the piston uncovers the
discharge passages, and during the latter part of the forward movement of the
piston and the first part of its return movement, and gas can only flow through
the valve into the cylinder space when the pressure in the space of the pipe is
greater than that in the cylinder space, that is to say during the forward move-
ment of the piston but only after the discharge has taken place, and on the
return movement of the piston during the whole duration of the movement.
A correct selection of the compression in the other space and also the constant
remaining volume of the pipe (reservoir) is thus of the greatest importance
because when the proportions are incorrect the gas is either driven too quickly
into the cylinder and thereby forced through the cylinder or on the other hand
too little gas reaches the cylinder space. In the first case great resistance and
loss of gas is experienced, in the latter insufficient weak charges result. The
other space and pipe must therefore be so arranged that good charges are attained
in the cylinder space with the smallest possible resistance and without loss of
gas.
The action of the apparatus on the mean number of revolutions:
The weight and movement of the inlet valve has an influence on the rapid
and complete filling of the cylinder space and the movement and weight of the
valve must be brought into an entirely correct proportion to the volume of the
pipe and to the compression in the other space if the valve is to suitably admit
the mixture of gas and close rapidly enough at the right moment so that practi-
cally none of the gas already existing in the cylinder space can be forced back-
ward towards the pipe by the commencing compression in the working cylinder.
The movement and the weight of the automatic inlet valve also act in this
sense on the mean number of revolutions of the motor because in the case of
smaller charges (caused by a driving back of a portion of the gas already
admitted) it is naturally smaller than when the charges are of full quantity,
which latter are obtained by a correct closing of the valve. An alteration of
the mean number of rotations for this motor is attained by small differences
in weight and movement with an equal load and conditions otherwise unaltered.
For a changing load, or when the machine is running empty, it is necessary
in order to maintain a given number of revolutions to regulate the machine by
means of a suitable speed regulator (centrifugal governor or the like) which
here must act by diminishing the mixture of gas because no regulating discharge
or the like is here present.
The unregulated and springless valves employed in this motor are entirely
closed to the outside and therefore are exposed to no deleterious outer influences.
In order to render entirely unnecessary a frequent grinding down of the valve
seats, the free moving valves which are well guided above and below are made

page_text: to play not only up and down but also constantly to rotate on their vertical
axes. An automatic and constant grinding down of the valve seats is thus
attained to a certain extent so that they are entirely prevented from becoming
untight.
This rotary movement of the valves may be attained in several simple ways of
which only two arrangements will be mentioned. First, the feed passage may
be arranged to one side so that the inflowing gas acts on the vanes or ribs of the
valve as on a paddle wheel. Second, the guide bars or vanes may be spiral.
Dated this 16th day of May 1898.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicants.
Improvements in Gas and like Engines.
We, HEINRICH HILDEBRAND, of 2, Pesenbachstrasse, WILHELM HILDEBRAND,
of 1a, Frauenhoferstrasse, and ALPHONS BRUCKMANN, of 5, Schönfeldstrasse, all
of Munich, in the Empire of Germany, Merchant, Engineer, and Austro-Hun-
garian Consul, respectively, 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 has for its object a valve for two-stroke-cycle gas engines for
which valve all governors and regulating appliances are dispensed with. The
engine is regulated entirely automatically and the valve is also operated auto-
matically. By this means a very even running and the highest economy is
obtained.
In the accompanying drawings:-
Figures 13 are longitudinal sections of the engine showing various posi-
tions of working. C is the cylinder connected with the gas pressure pipe D, an
ungoverned inlet valve V being arranged between cylinder and gas pipe. P is
a discharge port the closing slide valve of which is constituted by the piston K
of the engine. Z is the igniting device which may be of any suitable kind,
such as an incandescent tube lighter.
The mode of working is very simple and is as follows:-
Figure 1 shows the engine at the moment of the explosion. The piston is
driven forward in the direction of the arrow and expansion of the ignited gases
takes place producing the working stroke. The valve V is closed at the moment
of the explosion and remains closed until the piston in its forward movement
uncovers the discharge port P. At this moment the exhaust gases escape through
said port to the outside, causing the inlet valve V to open, in consequence of the
diminution of pressure produced in the cylinder and the excess pressure in the
gas pipe D, so that gas enters the cylinder expelling before it the escaping gases
of combustion. The piston has in the meantime attained its front dead point
Figure 2 and commences the return stroke. At the moment when the piston
again covers or closes the discharge opening and the compression again com-
mences in the cylinder the inlet valve is closed by the compression pressure,
Figure 3. The compression continues until the piston has reached its rear dead
point whereupon the ignition and explosion takes place and the movements
hereinbefore described commence afresh.

page_text: As may be gathered from the foregoing the opening and closing of the inlet
valve is effected without any governing mechanism by the variation of the excess
pressure in the supply pipe and the cylinder on the piston opening and closing
the discharge port. it will be easily seen that a greater or lesser speed of the
piston produces a shorter or longer opening of the discharge port and conse-
quently also of the inlet valve. Thereby as the movement of the latter is
limited, more or less gas will enter the cylinder producing smaller or greater
charges. In other words an excellent automatic regulation of the running of
the machine is thus afforded.
The pressure in the gas pressure pipe D may of course be obtained in any
suitable manner it may for instance be supplied from a gasometer. In the form
of construction of the apparatus shown in the drawings, the working piston is
used for bringing gas into the pressure pipe D and to keep the gas in the latter
under suitable pressure.
For this purpose the piston acts also as the plunger of a pump the body of
which is formed by the rear part of the cylinder, the suction pipe of which is
the pipe S and the pressure pipe of which is the pipe D.
On the return of the working piston gas is thus drawn in through the pipe S,
the suction valve V₁ opening and on the forward movement of the piston said
gas is forced into the pipe D whilst the said valve Vis closed, causing a com-
pression of the quantity of gas introduced in this manner until the opening of
the inlet valve caused by the uncovering of the discharge port P takes place.
By the above described pump arrangement which serves both for introducing
gas into the pipe D and producing a suitable pressure therein, the highest
economy in gas consumption is attained as it is at once evident that the pump
piston always draws in the same quantity of gas as flowed previously into the engine
from the pressure pipe for the purpose of charging the engine. If therefore
much gas is consumed in the engine, much gas will be drawn in by the pump
but if little gas be used only little gas is drawn in by the pump. The introduc-
tion of gas is thus always regulated by the consumption and in this manner an
automatic gas regulation and thereby the greatest economy is effected.
In hydrocarbon engines in which the hydrocarbon is introduced in liquid form,
the arrangement hereinbefore described for drawing in and compressing gas is
of course utilized for drawing in and compressing atmospheric air which opens
the ungoverned inlet valve V when the outlet or discharge port is uncovered in
order to allow said air to enter the cylinder and so be mixed there with the
hydrocarbon, which in the meantime has become vaporized. The functions of
the machine are otherwise in no way altered.
Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed, we declare that what
we claim is;-
1. In two stroke cycle explosion engines having pistons forming the slide for
closing the outlet or discharge port, the arrangement of an ungoverned inlet
valve adapted to be opened, on the uncovering of the discharge port, by the pres-
sure in the pressure pipe and adapted to be closed by the compression on the clos-
ing of the discharge port, the actual speed of the piston producing a longer or
shorter opening of the discharge port, and consequently a longer or shorter admis-
sion of gas into the cylinder and thereby a greater or lesser charge, substantially
as herein before set forth.
2. In a two stroke cycle explosion engine such as described, the arrangement
whereby the gas is drawn in by the piston on its return stroke and forced by its
forward movement into the gas pressure pipe, the gas being thereby at the
same time compressed, the quantity of gas introduced in this way corresponding
to the quantity of the gas consumed in the engine, substantially as herein before
described.

page_text: 3. A modification of the two stroke cycle explosion engine hereinbefore des-
cribed consisting in a hydrocarbon in a liquid form being introduced and the
ungoverned valve being opened by air, the introduction of the latter and also its
compression in the manner described being effected by the working piston, sub-
stantially as hereinbefore described.
Doted this 2nd dor of Wahmuany 1800
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicants.