Improvements in and relating to Oil or Gas Engines,
Year: 1896

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Oil or Gas Engines,
I, HIRAM STEVENS MAXIM, of 18 Queens Gate Place, in the County of Middlesex,
Mechanical Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to oil or gas engines and is particularly applicable to engines
for horseless carriages and for other purposes where an exceedingly light and active
motor is required. Gas and oil engines are now very commonly constructed to
perform what is known as the "Otto cycle, that is to say, a cycle in which work is
done only at every alternate outward stroke of the piston. Therefore in such an
engine no less than four cylinders are required to perform the said number of working
strokes as an ordinary single cylinder steam engine and eight separate cylinders are
required to effect one revolution of the crank without a fly wheel, which can be done
with a two cylinder steam engine as for example a locomotive engine. Moreover a
gas engine performing the "Otto" cycle is capable of only very slight variation of
speed. It must work at a rather high speed or not at all and it is impracticable to
provide it with reversing gear. Therefore such engines are not advantageously
applicable for the purpose of a road carriage which must be able to run either fast or
slow, and must be capable of being reversed at will and of being started at any time
without manual assistance.
According to my invention I construct an engine with two or more working
cylinders each of which will perform work with every outward stroke of its piston.
In some instances I arrange in conjunction with one or both of the working cylinders
an air pump the piston of which is preferably attached to the piston rod of the
working cylinder; or in some instances the cylinder may be so constructed that one
of its ends serves as the air-pump while its other end is used as the working
cylinder. I find it best to arrange the air pump as far as possible from the hot
cylinder.
I am aware that engines have been constructed in which one end of the piston rod
has been provided with a piston working in a cylinder and propelled by the pressure
of hot air or gas while another piston on the rod has been employed for compressing
the air, but in such engines, the pressure in the working cylinder never exceeds the
maximum pressure in the air-reservoir, consequently these engines are not as
economical as those using the "Otto" cycle in which the pressure exceeds that of
the compressed air in the air-reservoir.
In my engine the connecting rod may be attached directly to the pump-piston so
that the cross-head pin or pivot will be situated in a cool place and consequently the
piston will work better than if the said pivot were at the other end. The crank pins
are set at angles of ninety degrees from each other and are arranged in such a
manner as to balance the engine as nearly as possible.
The said engine will work in the following manner, viz. :-Suppose the engine is
ready for starting, the compressed air tank having a pressure of about forty five lbs.
to the square inch, the valve in the air passage is opened the compressed air enters
the cylinder and the piston is pushed forward as in a steam engine. When the

page_text: piston has moved through about one-fourth of its stroke it uncovers the ignition
tube, or otherwise causes the ignition of the charge of gas or vapour that has been
admitted to the cylinder. At this instant a valve operates to close the communication
between the compressed air tank and the cylinder and the charge being ignited the
pressure suddenly rises to about one hundred (100) lbs. to the square inch. In some
instances I allow the cylinder to be very hot especially where heavy petroleum is
used. Its temperature may be sufficiently high to ignite the gas or oil without any
special igniter and in such cases I obtain the desired result by not injecting the gas
or vapour until after the piston has travelled through about one fourth of its stroke.
I thereby obtain the same results as I do by igniting the charge by means of a
special igniter. If very heavy oil is to be employed and the cylinder kept hot as
above specified I find it advantageous to use a long piston provided with packing
rings at its outer end and to keep cool only that part of the cylinder in which these
rings work while the inner end of the piston may be loosely fitted in the cylinder and
made of material which will endure a high temperature. For instance the piston.
may be covered with asbestos with or without an external covering of "platinoid,"
which is a mixture of wrought iron and nickel. The end of the cylinder may also
be made of the same or similar material and heated with a Bunsen burner to a
temperature sufficient to ignite the oil. But where a light petroleum is used the
cylinder need not be kept at a high temperature. It can be jacketted throughout its
entire length, and the charge may be ignited at about one quarter of the piston's
stroke either by an ignition tube or an electric spark. As the piston moves outward
it performs work on the crank and at the same time compresses the air, the two
pistons being brought to a state of rest at the end of the stroke by the compressed
air in the air-pump.
In an engine of this kind it is necessary that a definite quantity of inflammable
material shall be introduced into the cylinder at, each stroke and I provide apparatus
which so operates that the admission valve or valves when opened at any particular
part of the stroke will not remain open. I prefer to employ for this purpose a device
which first raises a weight, and then by means of a tappet releases it so that the
weight in falling strikes the valve, and by its impact opens the same but allows it to
close again immediately. In this case the oil, which should be under a pressure
greater than that of the compressed air, enters the cylinder in a fine spray; or it may
be volatilized and enter the cylinder in the condition of vapour. The quantity of
fluid admitted may be varied by varying the force of the blow, the length of the
stroke, the force of the spring, the action of the tappet, or the size or shape of the
valve. The pressure on the oil should be at least one hundred (100) lbs. to the square
inch so that it may enter with great force into the cylinder. The oil may be
contained in a strong tank subject to the pressure of compressed air; or a small
pump may be arranged to pump a larger quantity of liquid than is required, the
superfluous oil being blown through a bye-pass at a pressure in excess of the pressure
of the compressed air in the tank.
When four cylinders are employed upon the same crank shaft the engine may run
either at a high or a low speed. Suppose that the engine is required to run slowly
on a slight downward grade, the liquid may be shut off and then if the cylinder is
hot the apparatus will work as a hot-air engine the only power developed being due
to the increased volume of the air entering the hot cylinder, and whenever more
power is required a larger or smaller quantity of oil can be admitted as required.
The speed of the engine may be reduced by closing a valve in the compressed air
passage.
If an automatic regulator or governor is required I prefer to employ one
constructed in the following manner; that is to say, a diaphragm is. connected with
the compressed air tank and with the oil-supply in such a manner that if the pressure
in the air tank rises above the pre-determined pressure it diminishes the quantity of
oil or gas introduced into the chamber, whereas if the pressure shall fall below this
point an increased quantity of oil will be introduced and the heat will be
correspondingly increased. In this manner the quantity of oil burned can be

page_text: automatically regulated according to the amount of work being performed. If the
load is light the engine may work simply as a hot air engine, whereas if the load is
heavy it will work as a gas or oil engine.
According to my invention I provide for reversing the engine as follows that is to
say, I use two sets of cams on one shaft arranged to actuate the induction and
exhaust valves; and capable of the required adjustments, or I may employ two shafts
each one having its own special cams. When a single shaft is employed the shaft
may be arranged to be pushel inwards to reverse the engine, whereas if two
shafts are used they may be arranged to be turned about a common centre so that
one or the other will come into its operative position according as the engine is to
run forward or backward.
My improved engine will work at any desired speed, and under very different loads,
and will work as weil with a heavy load as with a light load. It therefore requires
very much less gearing than other forms of gas or oil engines and may in fact be
geared directly to the axle of the carriage or vehicle on which it is used. The engine
may be arranged to permit one or more cylinders to be used as may be required and
can be adapted to the various conditions which affect the working of a road carriage
which not only has to run on the level but also has to mount and descend steep
inclines.
In some instances I provide for employing the engine as an air pump and thereby
retarding the vehicle in descending an incline.
The air reservoir may be of any convenient shape or size, but I prefer to construct
it of strong tubing completely surrounding the engine and serving as its foundation
and in some cases as the framework of the carriage. The oil-reservoir may be located
at any convenient part of the carriage and the water tanks may be arranged in such
a manner that the water can be fed into the parts to be cooled and can only escape
as steam, the water being employed for cooling the cylinder or the exhaust valve or
both as may be required.
1000
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.
Improvements in and relating
Engmes.
I, HIRAM STEVENS MAXIM, of 18 Queen's Gate Place, in the County of Middlesex,
Mechanical Engineer, do hereby declare the nature of this invention and in what
manner the saine is to be performed, to be particularly described and ascertained in
and by the following statement:—
My invention relates to oil or gas engines and is particularly applicable to engines
for horseless carriages and other purposes where an exceedingly light and easily con-
trolled motor is required. Gas and oil engines are now very commonly constructed
to perform what is known as the "Otto" cycle, that is to say, a cycle in which work
is done only at every alternate outward stroke of the piston. Therefore in such an
engine no less than four cylinders are required to perform the same number of work-
ing strokes as an ordinary single cylinder double acting steam engine, and eight
separate cylinders are required to effect one revolution of the crank shaft without a fly
wheel, which can be done with a two cylinder double acting steam engine as for
example a locomotive engine. Moreover a gas engine performing the "Otto" cycle
is capable of only very slight variation of speed. It must work at a rather high speed
or not at all and it is impracticable to provide it with reversing gear. Therefore

page_text: such engines are not advantageously applicable to the propulsion of a road carriage
which must be able to run either fast or slow, and must be capable of reversal at will
and of starting to work at any time without manual assistance.
According to my invention I construct an oil or gas engine with four or other
suitable number of working cylinders arranged in pairs, each of which cylinders will
perform work with every outward stroke of its piston, and I arrange in conjunction
with one or each of the working cylinders an air pump, the piston of which is prefer-
ably attached to the piston rod of the working cylinder; although in some instances
the working cylinder may be so constructed that one of its ends serves as the air-
pump and its other end as the working cylinder. I find it best to arrange the air
pump a considerable distance from the hot eylinder so that it will not become unduly
heated thereby.
I am aware that engines have been constructed in which one end of the piston rod
has been provided with a piston working in a cylinder and propelled by the pressure
of hot air or gas, while another piston on the same rod has been employed for com-
pressing the air, but in such engines, the pressure in the working cylinder never
exceeds the maximum pressure in the air reservoir consequently these engines are
not as economical as those using the "Otto" cycle in which the pressure exceeds that
of the compressed air in the compression chamber.
In my engine, I employ a pressure within the air rese voir at starting of about
forty five lbs. to the square inch, so that when the valves in the air passage leading to
the working cylinder is opened, the compressed air enters the cylinder and actuates
the piston as steam does in a steam engine. When the piston has performed a
portion of its stroke, say one-fourth, I allow the ignition of the charge of gas or
vapour that has been previously admitted to the cylinder and mixed with the com-
pressed air, to take place, the communication between the compressed air reservoir
and the cylinder being at this instant closed by a suitable valve. The periods at
which this ignition takes place may be regulated by varying the intervals between
the oil delivery into the cylinder, or by locating the ignition tube in such a position
in the cylinder that it will be uncovered by the piston as the latter performs its
stroke, or by mean of suitably arranged electric contacts that will cause sparking to
take place within the cylinder at the desired intervals to ignite the explosive charge.
Thus, in some instances I allow the cylinder to be very hot especially when charges
of heavy petroleum are used, so that its temperature may be sufficiently high to
ignite the charges without any special igniter and in such cases I obtain the desired
result by not injecting the charge until after the piston has performed about one-
fourth of its stroke as above stated. If very heavy oil charges are to be employed
and the cylinder is kept hot as above specified, I find it advantageous to use a long
piston provided with packing rings near its outer end and to keep cool only that part
of the cylinder in which these rings work, the inner end of the piston loosely fitting
the cylinder and being made of or provided with material which will endure a high
temperature. The end of the cylinder inay also be made of the same or similar
material and be heated with a suitable burner to a temperature sufficiently high to
cause ignition of the oil charge. But where charges of light petroleum are used the
cylinder need not be kept at a high temperature; it can be jacketted throughout its
entire length, and the explosive charge may be ignited either by an ignition tube or
an electric spark.
When ignition of the charge occurs the pressure within the working cylinder
suddenly rises to about sixty pounds to one hundred lbs. to the square inch. As the
piston moves outward it performs work on the crank and at the same time operates
the air pump piston to compress the air, the two pistons being brought to a state of
rest at the end of the stroke by the compressed air.
In my engine it is necessary that a definite quantity of oil or vapour shall be
introduced into the working cylinder at each stroke and for this purpose I provide
valve apparatus of the kind hereinafter specified, which is actuated by a tappet or
finger on the piston or some other appropriate noving part of the engine.
I provide the engine with a regulator or governor comprising a flexible diaphragm

page_text: which is connected on one side with the compressed air supply and on the other side
with the oil-supply valve mechanism in such a manner that the quantity of the oil or
gas admitted to the working cylinders will be automatically controlled by the pressure
of the air supply. This regulator also avoids excess of oil being delivered to the
cylinders and prevents consequent imperfect combustion.
For reversing the engine I may use any well known device, but when poppet
valves are used I prefer to employ two sets of cams on a shaft arranged to actuate
the induction and exhaust valves, and capable of the required adjustments; or I may
employ two shafts each having its own special cams. When a single shaft is
employed it may be arranged to be pushed longitudinally to reverse the engine,
whereas if two shafts are used they may be arranged to be turned about a common
axis so that one or the other will come into its operative position according as the
engine is to run forward or backward. Or if slide valves be employed I may
provide means for altering the position of the eccentrics working such valves.
In order that my said invention may be clearly understood and readily carried
into effect, I will proceed to describe the same more fully with reference to the
accompanying drawings in which :-
Figure 1 is a sectional plan of my engine adapted to be worked by charges of oil
and air.
Figure 2 is a side elevation thereof,
Figure 3 is a longitudinal section taken through one of the working cylinders and
air-pumps.
Figure 4 is a transverse section taken approximately on the line 1-1 of
Figure 1.
Figure 5 is a longitudinal section of one of the oil inlet valves employed in this
engine.
Figures 6, 7 and 8 are detail views of one of the eccentrics hereinafter referred to;
Figure 6 being a sectional elevation; and Figure 7 a longitudinal section thereof,
while Figure 8 is a plan of one of the parts detached.
Figure 9 is a longitudinal section and Figure 10 an end elevation of a pump for
supplying the oil charges under pressure to the engine.
Figure 11 is a longitudinal section taken through one of the working cylinders of
a slightly modified construction of my engine, and
Figure 12 is an end elevation thereof shewing the mechanism employed for
reversing the engine.
Figure 13 is a sectional plan of the aforesaid mechanism.
Figure 14 is a longitudinal section and Figure 15 a sectional end view of the
valve employed in Figure 11.
Figure 16 is a plan of the end portions of the working cylinders showing
another device for actuating the valves to reverse the engine or vary its speed, and
Figure 17 is a local section taken through one of the air inlet valves illustrated in
Figure 16 and shewing adjustable means for regulating the extent to which the said
air inlet valves are opened during the working of the engine.
Referring more particularly to Figures 1 to 5, A A are the working cylinders
and B B are the air pumps. C is the air-reservoir connected with the air pumps by
the pipes CC2 C2. D is the crank shaft and D¹ D' are the cranks thereon. È is a
sprocket wheel mounted on the crank shaft and adapted to transmit motion by means
of a driving chain to the axle F which may be the driving wheel axle of the vehicle.
GG are horizontal standards by which the working cylinders and air pumps are
rigidly connected together. These standards are provided with bearings GG¹ in
which the crank shaft D revolves and with other bearings G2 G2 in which the driving
wheel axle F revolves.
The working cylinders are connected together in pairs side by side, each pair being
provided with a slide valve a that works transversely with respect to the cylinders
and alternately opens the inlet ports al al to the compressed air supply and to the
exhaust passage a2. The slide valves are similar in construction to ordinary steam
slide valves and work in valve boxes or chests A* which communicate with the air

page_text: reservoir or air pumps by branch pipes C. At the junction of these branch pipes a
throttle valve C is provided for the purpose of regulating the amount of compressed
air passing to the cylinders. This valve is furnished with a stem C' to which
suitable lever mechanism is connected for enabling the driver of the vehicle to con-
veniently adjust said valve. The said slide valves are actuated by rocking shafts a³
having arms a a' the latter of which are connected to the slide valves by links a
and rods a' passing through suitable stuffing boxes. The arms a' are connected by
rods a to eccentrics a worked from the crank shaft of the engine.
For reversing the engine I construct the sheave of each eccentric in the manner
shewn in Figures 67 and 8, so that it is capable of sliding transversely on the crank
For this purpose I form the sheave with a transverse slot a having diagonal
teeth formed on one of its edges, and gearing with these teeth are corresponding
diagonal teeth formed on a sliding rod a working longitudinally in the crank shaft.
By sliding this rod to or fro through the intervention of a hand lever acting on the
arms a, the position of the eccentrics can be varied by the driver of the engine and
the slide valves correspondingly altered in accordance with the direction in which the
vehicle is to travel.
a13 as are non-return valves which are situated between the slide valves a and the
pipes leading to the air valve C, these valves serving to shut off the connection
between the valve box or chest Ax and the air pumps when the pressure within the
said chest A* exceeds that of the air pressure.
The working cylinders are arranged in alignment with the air pumps, their pistons
being coupled together by connecting rods A', A'; B B the former of which drive
the crank shaft. The rods A¹ B₁ are connected together by a transverse pin a¹ and
the head of the rod B is formed with a curved slot B2 for the crank pin to work in
during the revolution of the cranks and the oscillation of the rods A B as they
alternately assume a straight and oblique position.
By arranging the connecting rods in this manner, I am able to bring the pump
cylinders and the working cylinders closer together than would be possible if a simple
rod connecting the two pistons together were employed, and yet I am still able to
keep the air pumps a sufficient distance from the working cylinders to ensure the
former being kept cool.
The connecting rod A¹ is preferably made hollow as shewn, so as to contain
lubricant which can flow through a perforated tube A and the passages A and
thereby reach the crank pin, the transverse pin a, and the pivot pin by which the
rod is coupled to the piston. At every outward stroke of each of the air pump
pistons air enters the pump from the atmosphere through the openings bbb in the
piston. During the inward stroke of the pump piston the openings are kept closed
by a flexible disc valve 63 and the air within the pump is forced into the air reservoir
through the openings 6 which are kept closed against the return of the air by a
flexible disc valve b.
Each piston of the working cylinders is provided with packing rings A and the
inner portion A' of said piston is prolonged and made of less diameter than that of
the interior of the cylinder so as to be out of contact therewith. As this prolonged
portion of the cylinder is subjected to a high temperature I prefer to cover it with
asbestos in a coating of enclosed "platinoid," which is a mixture of wrought iron
and nickel, in order that it may withstand the high temperature and also prevent
conduction of heat.
The end of the working cylinder is closed by a cap or cover A which constitutes
the explosion or combustion chamber. This portion of the cylinder is unprovided
with the water jacket A' and if desired its end may be furnished with a lining of the
aforesaid platinoid or may be made entirely of platinoid. The explosive mixture of
oil and air enters the said chamber A' through the ports A8. A A10 are electric
ignitors which at the required portion of the stroke of the piston are caused to
spark" by any suitable contact device which is actuated to close an electric circuit
by the revolution of some revolving part of the engine as is well understood.
Although in the drawings I have shewn an electric ignition device I, in many cases

page_text: prefer to employ an externally arranged lamp for heating an ignition tube to effect
the explosions. This lamp may also be used in addition to the electric ignition
device so as to raise the temperature of the cylinders sufficiently to cause the
vaporization of the oil charges prior to ignition thereof.
II are the oil inlet valves each of which is arranged to be actuated by a finger or
tappet A" on the pistons of the working cylinders as the said pistons reciprocate.
These valves may be constructed to open directly by the movement of a valve rod or
indirectly by the pressure of the oil forced against the valve by a plunger, the said
valve rod or the plunger being actuated by the aforesaid finger or tappet A" as
hereinafter explained.
The oil inlet valve illustrated in Figure 5 is of the plunger type and comprises
an outer casing formed with a central passage i to which the oil gains access
from the inlet by transverse holes i¹. Within the passage i are two valves i³
the former being the outlet valve and the latter a non return-valve. The said valve i²
is normally kept closed by a spring which is connected at one end to the valve
and at the other end to a cross bar i. is the plunger the stem of which works in
a stuffing box and terminates at its outer end in a slotted head 7. This plunger
is kept in its outward position by a spring ; is another spring for keeping the
gland of the stuffing box in place.
Extending transversely across the engine is a rocking shaft , having arms "to
whose outer ends are pivotally connected levers 12. The free ends of these pivoted
levers engage with the aforesaid slotted heads 7. Situated about midway of the
length of the said transverse rocking shaft 10 is another arm is acted upon by a
spring 14 which keeps the said arm 13 constantly pressed against a plunger 15
forming part of the regulator I. This regulator consists of a box or casing within
which is a flexible diaphragm upon one side of which the inner end of the aforesaid
plunger is located. The other side of the said diaphragm communicates, by
means of a pipe 20, with the aforesaid compressed air pipe C3 so as to be acted upon
by the pressure of the air supplied to the engine as such air passes the aforesaid
throttle valve C. The free ends of the pivoted levers 12 are formed with lateral
inclines 7 against which the aforesaid fingers A" on the pistons act to open the oil
inlet valves.
It will be obvious that the aforesaid arm 13 is subjected to two opposed pressures
that is to say, a pressure due to the spring i and a pressure due to the compressed
air within the regulator 1'. Thus the rocking shaft will be shifted angularly in a
direction depending on which of the aforesaid pressures predominates. By such
angular movement the outer ends of the arms " will be moved up or down, and by
correspondingly shifting the pivoted levers 12, will thereby vary the extent to which
the inclines on the said pivoted levers protrude into the path of the fingers A", so
regulating the extent and the duration of the opening of the oil inlet valves. Thus
the amount of the oil charges supplied to the cylinders by the oil inlet valves will he
automatically regulated or varied by the amount or pressure of the compressed air
passing the valve C* from the compressed air reservoir or pumps. Therefore by means
of this governor or regulator the driver of the vehicle can, by altering the said air
valve C, very conveniently regulate the speed of the engine.
In some cases I supply the oil to the engine by a pump such as that shewn in
Figures 9 and 10 each stroke of the pump plunger supplying the oil to the inlet
valves. J is the pump barrel provided with branches J J2, to one of which the oil
inlet J is connected and to the other of which is connected the oil outlet J. jis
the pump plunger which works through stuffing boxes, whose glands are kept
in place by a spiral spring interposed between them. The space within which
this spring is located is prefembly filled with castor oil, glycerine or other fluid not.
soluble in the petroleum or other oil used, to reduce the liability of leakage of the
oil supply at the aforesaid stuffing boxes. The branches J J of the pump are
constructed in sections, with a valve j between contiguous sections; the various
sections being held together by means of long bolts passing through lugs on the
end pieces of the branches J J and the pump barrel J. The valves in the branch Ji

page_text: open at each instroke of the pump plunger while those in the branch J remain
closed; at each outstroke of the pump plunger the valves in the branch J2 open
while those in the branch J1 remain closed. I prefer to locate between the various
valves perforated partitions which serve as stops to limit the opening of the
valves. For ensuring that sedimentary matter and like impurities that the oil may
contain shall not pass into the working cylinders I employ the strainer. J' is a
relief valve past which the oil can escape back to the reservoir through the bye-pass J'
in the event of the oil pressure becoming too great.
In Figures 11 to 17 I have shown a modification of my engine in which one end
of the working cylinder serves as the explosion chamber and the other end as the air
pump. In this case also I have shewn the engine provided with poppet valves
instead of slide valves for controlling the air inlet to and the exhaust from
the cylinders.
As in the previously described engine there may be any desired number of
pairs of cylinders A arranged side by side; in the drawing I have shewn only
one pair leaving it to be understood that this number may be increased according
to circumstances. Where possible I have employed the same letters of reference to
indicate in these figures parts similar to those already referred to in the preceding
figures.
A12 is the piston which in addition to the prolonged portion A5 is provided with a
prolongation or trunk A working through a stuffing box A". The annular space B
of the cylinder surrounding the said trunk constitutes the air pump which is connected
by the pipe C to the air reservoir, a non-return valve Ce being provided in the said
pipe. is a branch pipe connecting the pipe C with the air inlet valves C, and C
is the throttle valve by which the air inlet to the cylinders is controlled by the
engine driver as already explained with reference to Figures 1 and 4. CC are the
exhaust valves. Both these sets of valves C7 and C8 are operated by cam pieces or
tappets on a rotary shaft. In Figures 11, 12 and 13 I have provided two rotary
shafts K K each provided with two sets of cam pieces or tappets kk' the former of
which, viz k act upon the air inlet valves C7 and the latter on the exhaust valves C³.
The shafts K K¹ are mounted in bearings K2 formed on a sleeve K³ carried by a
central shaft K, motion being transmitted to the said shafts K K¹ from the crank shaft
of the engine, by means of helicoidal gearing K and toothed wheels K K K'. The
said cam pieces or tappets k k¹ on one shaft K are arranged in reverse order to those
on the other shaft K₁ so that by turning the said sleeve K³ a half revolution about
its shaft K by a handle K8 the reverse set of cam pieces can be brought into action
and the engine be thus reversed. K is a spring catch to retain the handle K
in either of its extreme positions.
Instead of reversing the engine by a rotary movement of the shafts carrying the
cam pieces or tappets I may employ a longitudinally sliding shaft as in Figure 16,
this shaft being actuated by a hand lever . In order to regulate or vary the
admission of air to the engine I provide the air inlet valves with vertically sliding
wedge pieces K¹ (see Figure 17) which are adapted to be shifted by links K12 and
crank arms K. By adjusting the position of these wedge pieces K" the stems of
the poppet valves will be acted upon sooner or later in accordance with the
position of the wedge pieces and the said valves will be kept open for a longer or
shorter time.
The automatic regulator I employed in this engine is similar to that employed in
the engine previously described, one side of the flexible diaphragm of such regulator
being acted on by the compressed air entering through the pipe and the other
side being acted on by the plunger 15. In this case however the said plunger
is connected to a pivoted or swinging bracket L instead of to the valve mechanism
before described. The air pressure within the regulator tends to keep the
said bracket L raised while a spring L' tends to keep it depressed, the said
bracket therefore varies its position in accordance as the pressure of the compressed
air or that of the spring predominates. This bracket has an arm L which
normally occupies a position slightly below the horizontal, that is to say out of

page_text: parallelism with the longitudinal axis or line of travel of the piston A. This arm
carries a rod which is capable of slight longitudinal movement and on which is
mounted a sliding weight or block l' that is normally kept in the position in which
it is represented in Figure 11 by a spring . There is a shoulder on the said
rod against which the weight bears but said weight is normally prevented from
shifting the rod by the resistance of another spring . The piston A¹s has a spring
tappet A" which, each time the piston moves outwardly, acts on the weight and
pushes it along the rod thereby compressing the spring 12. By reason of the said
arm L not being parallel with the line of travel of the piston as above stated, the
said spring tappet releases the weight after performing a portion of its stroke and as
a consequence the said weight flies back under the action of the spring (2 and strikes
a blow upon the shoulder of the rod 1, whereby the latter is suddenly shifted
longitudinally. This movement of the said rod is transmitted to the valve
(Figures 14 and 15) within the valve casing I by links connected to a spindle 7
carrying a dog 18 which acts on a collar on the said valve rod 15 to actuate the
latter. Thus the oil valve is momentarily opened for a time depending upon the
force of the blow delivered by the weight l, or in other words upon the extent to
which the said spring has been compressed before the release of the weight, and the extent
to which such spring is compressed depends on the position into which the arm L' is
placed by the aforesaid regulator I which as already stated is actuated by the pressure
of the air admitted to the engine.
The quantity of the fluid admitted by the valve can be adjusted by varying the
force of the blow struck by the weight, the length of its stroke, the force of its spring,
the action of the tappet, or the size or shape of the valve. I supply the oil to the
aforesaid valve from an oil reservoir containing the oil under pressure produced by
compressed air admitted to the said reservoir; such pressure should not be less than
one hundred pounds to the square inch.
In my engine when four cylinders are employed as described with reference to
Figures 1 to 4, the engine can be run either at a high or a low speed. For instance
if the engine be required to run slowly on a slight downward grade, the oil charges
may be shut off by operating a suitable valve interposed between the oil reservoir and
the oil inlet valves, then if the cylinders be hot and only the air be admitted to the
cylinders the engine will work as a hot-air engine, the only power developed being due
to the increase in the volume of the air entering the hot cylinders, and if more power
be required the requisite quantity of oil can be admitted by regulating the aforesaid
oil valve as required. The speed of the engine can be reduced by more or less closing
the throttle valve C' in the compressed air passage.
By completely cutting off the compressed air supply and the oil supply to the
working cylinders, when the vehicle is descending inclines the engine will act as an
air compressor and thereby retard the travel of the vehicle and store up in the air-
reservoir the compressed air.
The air reservoir may be, as shewn in the drawings, in the form of a wrought iron
vessel, or it may be constructed of strong tubing surrounding the engine and serving
as its foundation or as the framework of the carriage.
The oil reservoir may be located at any convenient part of the carriage and the
water tanks for supplying cool water to the jackets of the cylinders and other parts
to be cooled may be arranged in such a manner that the water can be fed to those
parts to cool them and escape only as steam. It is particularly desirable to keep the
slide valves cool and this can be effected by arranging the water jacket in close
proximity to the valve box or chest or by completely surrounding the said valve chest
with the water jacket. The said valves are also provided with a lining a composed
of a material that is a non-conductor or bad conductor of heat such as asbestos or
platinoid.
My improved engine will work at any desired speed and under very different loads,
and will work as well with a heavy load as with a light load. It therefore requires
very much less gearing than other forms of gas or oil engines and may in fact be
geared directly to the axle of the carriage or vehicle on which it is used. The engine
B

page_text: may be arranged to permit one or more cylinders to be used as may be required,
and can be adapted to the various conditions affecting the working of a road
carriage which not only has to run on the level but also has to mount and descend
steep inclines.
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. An engine in which the first portion of the piston's stroke is effected by the
pressure of air compressed before admission to the cylinder and the remainder by
pressure due to the combustion of oil or gas in such compressed air.
2. A gas or oil engine adapted to work, either as a hot air and explosion engine or
as a hot air or explosion engine.
3. The working cylinders arranged side by side in pairs to which cylinders
compressed air is admitted by means of transversely sliding valves substantially as
described.
4. The combination substantially as described with the air supply passages leading
to the working cylinders, of valves that close the said passages when the pressure in
the valve chest exceeds that of the air supply.
5. In a gas or oil engine the combination with the aforesaid transversely moving
slide valves of mechanism whereby their position can be varied by sliding their
eccentrics transversely on the crank shaft substantially as described.
6. The arrangement of the slide valves in such a manner that they will be
prevented from becoming unduly heated by the exhaust gases substantially as
described.
7. The slide valve lined with a material that is a non conductor or bad conductor
of heat for the purpose specified.
8. The combination with the working cylinder of an air pump arranged in alignment
with the said cylinder and having its piston coupled to the working cylinder piston
by rods connected to the crank substantially as described.
9. An oil or gas inlet valve constructed substantially as described to permit the
oil or gas to be forced into the working cylinder against the pressure existing therein
and in definite quantities at or immediately before the instant the explosion is to
take place.
10. An oil or gas engine provided with means for regulating the quantity of oil or
gas admitted to the cylinders, by the pressure of the compressed air after the latter
has passed the throttle valve in the air passage.
11. The combination with the oil inlet valve of mechanism whereby the duration
or extent of opening of the said valve by the finger or tappet on the piston is
automatically regulated in accordance with the pressure of the air admitted to the
cylinders.
12. The combination with the oil inlet valve of a block or weight which is displaced
by a finger on the piston and when released operates the said valve by impact
substantially as described.
13. The combination with the oil inlet valve of a pivoted or swinging frame carrying
the aforesaid valve operating block or weight, the position of the eaid frame being
regulated by the pressure of the air supplied to the engine substantially as described
and for the purpose specified.
14. The modification of the valve operating and regulating mechanism wherein,
instead of a block or weight and swinging frame, an incline is arranged to be acted
upon by the aforesaid finger or tappet on the piston substantially as described.
15. An oil inlet valve constructed and adapted to operate substantially as described
with reference to Figure 5, or Figures 11, 14 and 15 of the accompanying
drawings.
16. An oil pump for supplying the charges of oil to the working cylinders
substantially as described with reference to Figures 9 and 10 of the accompanying
drawings.

page_text: 17. The combination with the induction and exhaust valves of a device provided
with two sets of cam pieces or tappets either of which can be brought into an
operative position by the engine driver substantially as described and for the purpose
specified.
18. The means for reversing and controlling the engine substantially as described
with reference to Figures 16 and 17 of the accompanying drawings.
19. In the said engine the working piston formed with a prolongation which is of
less diameter than the interior of the cylinder and which is constructed to endure a
high temperature substantially as described and for the purpose specified.
20. The use of platinoid for the protection of the parts of the working cylinder and
the piston that are subjected to a high temperature, substantially as described.
21. The construction of the working piston with an intermediate portion for carrying
the packing rings and with a prolongation at each end substantially as described with
reference to Figure 11 of the drawings.
22. A gas or oil engine having its parts constructed arranged and combined to
operate substantially as described with reference to Figures 1 to 4 or Figures 11 to 13
of the accompanying drawings.
Dated thin the dan
1007
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.