oreum Vapour or Spray.
Year: 1885

page_text: or Petroleum Vapour or Spray.
I, GOTTLIEB DAIMLER, of Cannstadt, Wurtemburg in the German Empire,
Engineer, do hereby declare the nature of my invention for "IMPROVEMENTS IN
MOTOR ENGINES WORKED BY COMBUSTIBLE GASES OR PETROLEUM VAPOUR OR
SPRAY" to be as follows:-
My invention relates to an improved construction of that class of motor engines
worked by combustible gases or petroleum vapour or spray, wherein a combustible
charge is only introduced at the end of every alternate instroke and fired at the
end of every alternate outstroke of the piston, by which stroke the charge is
compressed.
According to my present invention there is introduced into the cylinder, before
the introduction of the main charge of explosive mixture, a preliminary charge of.
combustible mixture or air, which is caused to enter through the piston so as to
drive out the residual products of combustion from the cylinder, and after the
introduction of the main charge a further supplemental charge of either combustible
mixture or air, also admitted through the piston, which three charges are then
compressed and fired.
By this means combustible charges of greater volume and purity from products
of combustion are obtained, resulting in a more perfect combustion whereby greater
speed is attainable with decreased consumption of gas and less loss of heat,
enabling the cheaper carbonic oxide gases, as for instance the so called "Dowson"
gas to be employed with advantage.
For operating in the above described manner, I construct an enclosed chamber
communicating with the end of the working cylinder opposite to that in which the
combustion of the charge takes place, in which chamber is an inlet valve for
combustible gas and air, so that the working piston at each outstroke draws a
charge of combustible mixture, or it may be of air only, into the chamber, and
compresses that charge during the instroke.
The chamber is of cylindrical shape having one side closed by a circular cover
and has its space almost entirely occupied by a double crank plate to the pin of
which the connecting rod of the piston is attached, the crank plate being made

page_text: heavy so as to act at the same time as a fly wheel. The piston has a passage
formed right through it which on the side where the combustion of the charge
takes place is closed by a valve held down by a spring bearing upon a loose sleeve
on the valve stem. At the bottom of the cylinder is a forked projection, which,
as the piston nears the end of its instroke, bears against the said sleeve and thus
frees the valve from the pressure of the spring. Thus assuming the piston during
its outstroke to have drawn a charge of combustible mixture into the crank
chamber, and to have compressed that charge during the instroke, during which
it will have drawn a combustible charge into the cylinder on the other side thereof,
then as the piston valve will be freed from the action of its spring towards the end
of that stroke, it will be forced open by the compressed charge in the chamber,
which charge will 'consequently enter the cylinder until the pressure is equalised
on both sides of the piston. By the following outstroke of the piston this combined
charge will be compressed, and being then fired, will cause the piston to perform
its working instroke, during which it will also compress another charge in the
crank chamber, drawn in by the previous outstroke. Towards the end of the
working outstroke, the piston valve will again be freed from the spring, and being
forced open by the compressed charge in the chamber, this charge will enter the
cylinder, driving out the residual products of combustion therefrom during the
outstroke of the piston and thus forming the beforementioned preliminary charge,
to which the main charge is added during the following instroke, to be again
supplemented by a further charge from the chamber at the end of that stroke ns.
above described.
It will be evident that the above cycle of operations may be varied by dispensing
either with the preliminary charge or with the supplemental charge, this being
effected by suitable valve gear whereby the admission of gas and air into the
cylinder from the crank chamber during the one or the other stroke of the piston
is prevented.
The firing of the charge is effected by bringing it, when compressed in contact
with a heated part of the gas inlet passage, consisting by preference of a tubular
lateral extension thereof heated externally by a flame. In order to prevent the
ignition of the charge from taking place before the piston is at the end of its
compressing stroke, and the crauk is on the dead centre, the last portion of the
charge is rendered weaker than the main portion, by partially closing the gas inlet
valve so as to restrict the inflow of combustible gas, while the air supply remains
unrestricted. This is effected by forming an arm upon the rod that actuates the
discharge valve for the products of combustion, which arm is provided with an
adjustable screw that is caused to press upon the stem of the gas valve on the
downward motion of the rod.
This rod is actuated by the following mechanism for opening the discharge valve
for products of combustion at the end of the working stroke, and for preventing
such opening of the valve, so as to retain the products in the cylinder, when the
normal speed of the engine is exceeded. Upon one of the outer faces of the crank
plate are formed two cam grooves one of which is circular, its centre coinciding
with the axis of the crank plate, while the other starts from one point of the
circular groove and passing round the same at a certain distance therefrom enters
it again at another point. At this point is situated a switch which when the
engine is running at the normal speed, is held by a weighted arm acted upon by
a spring in such a position that a sliding block situated in the grooves will, on the
rotation of the crank plate, be made to pass from the outer groove into the inner
groove during one revolution and thence back into the outer groove, during the
next revolution by which means the before mentioned rod that acts upon the
discharge valve, and which is attached to the sliding block, is moved so as to force
the valve open against the action of a spring at every alternate rotation of the
crank plate. When the normal speed of the engine is exceeded, the centrifugal
action upon the weighted arm causes this to move the switch into such a position

page_text: that it prevents the sliding block from passing out of the inner circular cam groove,
so that the rod is prevented from acting upon the discharge-valve, and consequently
the cylinder remains charged with the products of combustion and no fresh
combustible charge will therefore be admitted until the speed of the engine has
again become reduced.
For starting the engine in the first instance, the driving pulley on the crank
shaft has a crank handle temporarily inserted into a hole therein, so as to rotate
the shaft by hand, and thus cause the piston to perform its strokes, the discharge
valve being temporarily kept open by a moveable strut to permit of this motion,
and the inlet valve to the crank chamber being also kept open by a screw for the
same purpose.
ABEL & IMRAY,
Agents for the Applicant,
28, Southampton Buildings,
London, W.C.

page_text: or Petroleum Vapour or Spray.
I, GOTTLIEB DAIMLER, of Cannstadt, Wurtemburg in the German Empire,
Engineer, 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:
My invention relates to an improved construction of that class of motor engines
worked by combustible gases or petroleum vapour or spray wherein a combustible
charge is only introduced at every alternate instroke of the piston, the improve-
ments being such that the gaseous charges employed are of greater volume and
are freer from products of combustion than those of engines heretofore constructed.
This is effected by introducing into the cylinder, both before and after the
admission of the main charge of gaseous mixture, additional charges of either
combustible mixture or of air introduced at every stroke by means of a pump,
formed in the working cylinder on the side of the piston opposite to that on which
the charge works. By one of these additional charges the products of combustion
are at the same time driven out of the cylinder.
•
For forming the pump and at the same time to avoid the use of a stuffing box
for the piston rod, and to render the construction of the engine more compact, the
crank is enclosed in a chamber provided with a suction valve for combustible
mixture or air, the piston being provided with a valve that opens automatically
when the piston is near the end of its instroke.
The ignition of the charge is prevented from taking place until the crank is at
the dead centre by causing an explosive mixture, poorer in gas than the cylinder
charge, to come in contact when compressed with a heated part of the adinission
passage, the moment of ignition being regulated by varying the proportion of gas
in the igniting mixture.
A further improvement relates to the mode of regulating the speed of the engine,
this being effected by bringing the valve gear to a standstill when the normal
speed is exceeded, the gaseous products of combustion being made to remain under
pressure in the cylinder, so that no fresh charge is admitted.
A further improvement relates to the regulator and starting device.
Fig. 1 of the accompanying drawings shews a vertical section of an engine
constructed according to my invention; Fig. 2 shews a part elevation and part
section at right angles to Fig. 1; Figs. 3 and 4 shew details.
A is the working cylinder with compression space A¹, at the upper end of which
is the inlet and discharge passage a; b is the inlet valve for the combustible
charge, c the discharge valve and d is the tubular extension on the inlet passage
heated externally. E is the piston with the inlet valve e, spring el and contact
plate e; F is a forked projection fixed to the framing with which fork the plate ell
comes in contact towards the end of each instroke of the piston, so as to force back

page_text: the spring e and thus cause the valve e to be free and automatic in its action
during a certain time before and after the dead centre of the instroke of the piston,
so as only to open when the pressure in the crank chamber exceeds that in the
cylinder; G is the gas-tight crank chamber with inlet valve gl for combustible
mixture and cover g¹¹, which latter is made sufficiently large to enable the crank
plate with its shaft to be taken out of the chamber. H¹H" are crank plates that
can be made heavy so as to serve at the same time as flywheels, and which occupy
the greater part of the chamber in order to make the pump chamber in the same
as small as possible and thus to obtain a compression in the same of from to
atmosphere overpressure. In order to simplify the machine, one of the crank
plates might be omitted.
o
The valve gear is actuated by a cam groove k formed in the crank plate H¹
and which passes twice round the crank shaft and returns into itself and in com-
bination with which is the sliding block o and the rod L which acts upon the rod c¹
of the escape valve c.
It will be seen that the cam groovek k is so formed, that at one revolution of the
crank, the sliding block o is moved from the groove into the groove ¹, whereby
the rod L is withdrawn from the rod c¹ of the escape valve c, which consequently
remains closed during the corresponding in and outstrokes of the piston; at the
next revolution of the crank the block o is moved back from the groove into the
groove whereby the rod Ľ in rising is made to open the escape valve, such
opening being effected after the piston has performed its working instroke.
The groove is circular and is connected by branches as shewn with the
groove by means of which the block o is made to pass from the one to the other.
The regulation of speed is effected by means of the governor arm m with spring
centrifugal action, and the switch n, which, on the normal speed being exceeded,
move out of the working position at Fig. 2 into the position at Fig. 3 whereby the
block o is caused to remain in the cam groove k¹ during the revolution of the
crank and the rod L is thus brought to a standstill causing the escape valve to
remain closed until, by the reduction of speed, the switch is again move back to
the position in Fig. 2. By thus retaining the gaseous products of combustion
under pressure in the cylinder, the supply valves b and c will remain closed and
consequently no fresh charges of combustible mixture will enter the cylinder during
that time. The governor m is suspended from the axis i and has a spring action
in the direction of rotation round this point. The switch n is formed with an
incline and is connected to the axis i by its extension which has a spring action at
right angles to the axis as shewn in Fig. 4, in order that in the event of the
edges n¹ o¹ meeting, they may escape one another, so as to allow o.to pass on the one or
the other side of n. The governor m is pressed inwards by a spring u in the contrary
direction to the centrifugal force due to the speed of rotation. The ignition of the
charge is effected by the compression of the charge by means of the working piston
whereby a certain part of the charge is brought in a compressed condition in
contact with the tubular extension d heated externally by a gas flame v.
In order to retard this ignition until the crank is on the dead centre at the com-
pressing outstroke, the last portion of the charge of combustible mixture is reduced
in strength from to that of the main charge, so that the passage a and tube d
will only contain such weak mixture during the compressing stroke. The weak
charge is produced by the action of the gas valve g which toward the end of the
suction stroke is pressed downwards by the arm of the valve rod and thus
restricts the passage of gas. By the adjustinent of the screws the strength of the
charge and consequently the in ment of ignition is accurately regulated. The
temperature of the cylinder can be kept tolerably high, and in the absence of
water sufficient cooling can be effected by a moderate current of air through the
surrounding jacket.
The engine is started by rotating the crank shaft by means of the crank handle
attached to the belt pulley w, the discharge valve c and suction valve g¹ being
opened, this being effected by placing the support p under the stop ou the valve

page_text: rod c¹ and by screwing inwards the screw t so as to open the valve g¹. The crank
handle is drawn out when the engine is started. The mode of operating is as
follows:
Just before the end of the working instroke the discharge valve is opened, the
pressure in the cylinder sinks below that in the pump chamber, the piston valve e
opens automatically in this position and admits a charge, of combustible mixture
under pressure, or of air, into the cylinder which drives the products of combustion
out in front of it. By the outstroke of the piston and by the charge of mixture or.
air forced in, the lighter products of combustion situated in the upper part of the
cylinder are.expelled through the discharge valve. The combustion space of the
cylinder is now charged with combustible mixture or air. To this preliminary
charge is now admitted during the instroke of the piston, the main charge entering
through the admission valve b such charge consisting of air mixed with either gas
or petroleum in the form of vapour or spray. During the first part of the instroke
the piston at the same time compresses a combustible charge drawn in beneath it
into the pump chamber until shortly before the end of the stroke, when the piston
valve e is rendered free in its action again, and the third portion of the charge
now passes from the pump chamber into the cylinder until the pressure in the two
is equalised. At the second outstroke of the piston the total charge is further
compressed and is ignited as above described when the end of the stroke is reached.
The above described mode of operating may be varied by omitting either the
preliminary charge or the supplemental charge of combustible mixture or air.
For this purpose, the admission valve g¹ to the crank chamber would be arranged
on the cover g beneath the rod L that actuates the discharge valve as in the above
described arrangement and for the first mentioned case where the preliminary
charge is to be omitted, the rod L would be made to hold the valve open by means of a
loop L' while it is rising during the working instroke of the piston, as shewn at Fig. 5,
so that the charge of combustible mixture or of air that had previously been drawn
in through the valve g¹ would be driven out again, and consequently there would
be no compressed charge in the crank chamber at the end of such working instroke,
whereas during the following instroke when the rod L would be in the lowered
position, the valve would remain closed, so that the before described supplemental
charge would then be formed. For the second above mentioned case, where the
supplemental charge is to be omitted, the valve g¹ would be arranged as shewn at
Fig. 6, it being held closed by a spring during the working instroke of the piston,
so that the preliminary compressed charge would be formed while, during the
following instroke, when the rod L would be moving downwards, this is caused to
press the valve open, so that the charge previously drawn into the crank chamber
would be forced out again.
When working with petroleum the gas passages must be modified in proportion
to the heating power thereof.
For cooling the cylinder a fan x may be provided on the engine shaft, propel-
ling air through the cylinder casing z.
The advantages resulting from this construction of motor engine are that by
means of the power combustible mixture and the large volume of the charge a more
effectual combustion takes place and that on account of the greater speed here
attainable, less loss of heat takes place, resulting in a decreased consumption of
gas, and lastly that with this arrangement the cheaper carbonic oxide gas, for
instance the so-called "Dowson" gas may be used with advantage.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I do not claim
generally a gas motor engine, every alternate instroke of which is a working stroke,
but I claim
1. In a gas or petroleum motor engine every alternate instroke of which is a
working stroke, the method of introducing into the cylinder firstly at the com-
mencement of the outstroke following the working instroke a preliminary charge of

page_text: combustible mixture or air through the piston, whereby the residual products of
combustion are expelled, secondly during the following instroke, the main charge
of combustible mixture and thirdly at the end of the said instroke a supplemental
charge of combustible mixture or air admitted through the piston, the said combined
charges being then compressed by the following outstroke and ignited substantially
as herein described.
2. In a gas or petroleum motor engine every alternate instroke of which is a
working stroke, the method of introducing into the cylinder, after the main charge
a supplemental charge of combustible mixture or of air admitted through the
piston at the end of the suction instroke, the combined charges being then com-
pressed by the following outstroke and fired, substantially as herein described with
reference to Fig. 5 of the drawings.
3. In a gas or petroleum motor engine, every alternate instroke of which is a
working stroke, the method of introducing into the cylinder before the main charge
a preliminary charge of combustible mixture or air admitted through the piston,
whereby the residual products of combustion are expelled from the cylinder before
the admission of the main charge, substantially as herein described with reference
to Fig. 6 of the drawings.
4. The combination, in a gas or petroleum motor engine, of the method of intro-
ducing a preliminary charge and a supplemental charge in addition to the main
charge of the cylinders, and the method of firing such combined charge by com-
pressing it while in contact with a heated surface substantially as herein described.
5. In gas or petroleum motor engines, wherein the ignition of the charge is
effected by its compression in contact with a heated surface, the method of retarding
the ignition till the crank is at or about the dead centre by introducing into the
admission passage a charge of combustible mixture weaker than that contained in
the cylinder substantially as herein described.
6. For producing a weaker combustible mixture for the list part of the cylinder
charge of a gas or petroleum motor engine, the use of a gas admission valve q
operating in combination with the arm and screws on the rod L so that the
valve is partly closed and the supply of gas consequently restricted during the
latter part of the suction stroke.
7. The circular cam groove k¹ connected with the outer cam groove k by means
of connecting grooves and a switch n so that when the switch is in one position,
the block o passes consecutively through both the grooves k and while when it is
in another position, the block o is caused to remain in the circular goove kl
substantially as and for the purposes set forth.
1
S. The governor arm m operating in combination with the spring u and the
spring switch n with incline and with the cam grooves and k¹ whereby, when the
normal speed of the engine is exceeded, the block o is caused to remain in the
groove k¹.
9. The method of regulating the speed of a gas or petroleum motor engine by
causing the discharge valve for the products of combustion to remain closed when
the normal speed is exceeded so that the products of combustion are retained under
pressure in the cylinder whereby the admission valves b and e for combustible
mixture are also kept closed and no fresh charge is consequently admitted either
above the piston or from the pump below until the speed is again reduced and the
discharge valve opened substantially as herein described.
10. In a gas motor engine, the use of a closed crank chamber acting as a pump
chamber, in which the crank is formed as a disc or discs in order more or less
completely to fill out the chamber, substantially as herein set forth.
11. The arrangement of the piston E, with valve e, kept closed by the
spring el, which is acted upon by the fork F so as to free the valve when the
piston arrives at the end of its instroke, substantially as and for the purpose
described.
12. In gas or petroleum motor engines, the enclosed crank chamber G, operating
in combination with the inlet valve g, cylinder A or piston E with valve C, so as

page_text: to constitute a compressing pump by which combustible mixture or air is com-
pressed and introduced into the cylinder through the piston, substantially as herein
described.
'
13. In gas or petroleum motor engines, the removeable crank handler operating
in combination with the pivotted strutt p for keeping the discharge valve open and
the screw for keeping open the suction valve g for starting the engine substan-
tially as set forth.