Improvements in connection with the Propulsion of Road or other Vehicles.
Year: 1895

page_text: Date of Application, 27th Aug.. 1895
Complete Specification Left, 27th May, 186-Accepted, 22nd Aug., 1896
Improvements in connection with the Propulsion of Road or other
Vehicles.
I, MICHAEL HOLROYD SMITH, of 161 Trinity Road, Upper Tooting, in the
County of Surrey, Engineer, do hereby declare the nature of this invention to be
as follows:-
The object of this invention is to produce an arrangement of apparatus whereby
oil gas or like engines may be satisfactorily employed for driving vehicles on the
public roads or in other places.
The power of what may be called an explosive engine whether using oil or gas
depends upon the strength of the explosion, which is immediate and of short
duration, and may be regarded as impact, the regulation of the speed depends upon
the frequency and force of such impact.
In a steam engine the acting pressure can be graduated in strength and duration
and can be kept on the full length of the stroke if required.
cannot be started against its load and cannot be reversed.
points in traction work.
An explosive engine
These are important
An explosive engine generally speaking has to be kept constantly running and
engaging and reversing clutches are usually employed in order to communicate its
power to the wheels of the vehicle. The power required to drive road carriages
varies through wide extremes being nothing down an incline, little on the level and
much when climbing a hill. The explosive impulse of the engine must therefore
be sufficient to force the carriage up hill though only occasionally required
to do so.
.1
14
An explosive engine generates so much heat that it has been usually necessary
to employ large volumes of water circulating round the cylinder to keep it cool,
this is easily done when they are employed to drive boats but the weight of water.
tanks is objectionable for carriages.
Explosive engines, however, possess many advantages over steam engines and one
of the objects of the present invention is to make them applicable for road
carriages while recognizing and endeavouring to overcome the difficulties above;
enumerated.
1 ..
According to this invention it is proposed to employ a small explosive engine
driving direct an air pump or compressor charging a receiver the receiver supplying
compressed air to a small air engine running at a high velocity and communicating
its power to the axle or wheels of the vehicle by means of worm or other
gearing.
The explosive engine and air pump are preferably so arranged that by fixing a
detachable handle in the fly wheel (when one is employed or a lever when one is
not) the air pump can be worked initially charging the receiver and the pressure
used to produce the explosive mixture, in the gas cylinder, thus securing if desired
an explosion, every revolution. When the gas engine is running charging the
receiver the pressure of air in the receiver may be made to operate a valve
controlling the admission of gas to the. engine and thus regulate the speed and
impulses of the engine alone or in conjunction with the governors.
As the gas engines duty is to keep the receiver charged maintaining a pressure
and volume of air to work the air engine it follows that if the air engine is doing
:
:

page_text: light work, the pressure in the receiver will rise and the load upon the gas engine
increase and unless some provision were made the receiver would burst or the gas
engine be pulled up, and therefore it is proposed to provide a relief valve in the air
pump chamber to be opened by the pressure of air in the receiver when it reaches
a determined point so that the gas engine would then be running light, until the air
engine again uses the air from the receiver and reduces the pressure when the relief
valve would close, and the gas engine still running would commence pumping fresh
air into the receiver.
When compressed air escapes from the exhaust pipe of an air engine intense cold
is usually produced the outlets becoming choked it is therefore proposed to 80
arrange the hot exhaust from the gas engine that it shall warm, the exhaust
valves etc. of the air engine and the cold exhaust from the air engine that it shall
cool the cylinder etc. of the gas engine.
In order to secure lightness the air receiver may be made to serve as foundation
or bed plate of the gas and air engines both of them running as before stated at a
high velocity, and the oil tank may be placed either below the air receiver or in
any convenient part of the vehicle. The stopping starting and speed of the air
engine may be controlled by valves and levers placed so as to be easily operated by
the occupant or driver.
The compressed air in the receiver may be used not only for the initial explosion
of the gas, but for all explosions. the gas, engine not having to produce a rotary
motion but only a reciprocating one may operate after the manner of some steam
pumps the air and gas admission valves being operated partly by a tappet motion
and partly by the pressure of air from the receiver.
For tricycles and light carriages where simplicity is of more importance than
economy the gas engine may be made to pump water into a receiver from whence
it passes to actuate a turbine or impact wheel.
D
improvements in connection with the Propulsion of Road or other
Vehicles:
I, MICHAEL HOLROYD SMITH, of 161 Trinity Road, Upper Tooting, in the
County of Surrey, 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:-
The object of this invention is to produce an arrangement of apparatus whereby
oil gas or like engines may be satisfactorily employed for driving vehicles on the
public roads or in other places.
The power of what may be called an explosive engine whether using oil or gas
depends upon the strength of the explosion, which is immediate and of short
duration, and may be regarded as impact, the regulation of the speed depends upon
the frequency and force of such impact.
In a steam engine the acting pressure can be graduated in strength and duration
and can be kept on the full length of the stroke if required. An explosive engine
as ordinarily constructed cannot be started against its load and cannot be reversed.
These are important points in traction work.
An explosive engine generally speaking has to be kept constantly running and
engaging and reversing clutches are usually employed in order to communicate its

page_text: power to the wheels of the vehicle. The power required to drive road carriages
varies through wide extremes being nothing down an incline, little on the level and
much when climbing a hill. The explosive impulse of the engine must therefore
be sufficient to force the carriage up hill though only occasionally required
to do so.
An explosive engine generates so much heat that it has been usually necessary
to employ large volumes of water circulating round the cylinder to keep it cool,
this is easily done when they are employed to drive boats but the weight of water
tanks is objectionable for carriages.
Explosive engines, however, possess many advantages over steam engines and
one of the objects of the present invention is to make them applicable for road
carriages while recognizing and endeavouring to overcome the difficulties above
enumerated..
According to my invention which I will describe by reference to the
accompanying drawings it is proposed to employ a small explosive engine such as
indicated at a Fig. 1 which drives directly or otherwise an air pump or compressor
such as which serves to charge a receiver c which supplies the compressed air to
a small air engine d running at a high velocity and communicating its power to the
shaft it is required to drive or to the axle or wheels of the vehicle either directly
or by means of worm or other gearing.
In order to secure lightness which is especially desirable in the case where the
above arrangement is employed to operate a motor car the air receiver c may be
made to serve as the foundation or bed plate for the explosive and air engines as
shewn in Fig. 2 and the oil tank may be placed either below the receiver or in 'any
convenient part of the vehicle, the stopping starting and speed of the air engine d
being controlled by valves and operating handles placed so as to be easily
operated.
When compressed air escapes from the exhaust pipe of an air engine intense
cold is usually produced, which may cause the outlets to become choked and it is
therefore proposed to employ an arrangement such as that shown in Fig. 3 in
which the water in the jacket round the explosive engine cylinder a circulates by
means of a pipe tank 2 and pipe 3 round the exhaust port and cylinder if desired
of the air engine d and thus imparts the heat the water has derived from contact
with the explosive cylinder to the ports etc. of the air engine, the water which has
then fallen considerably in temperature being returned by pipe 4 to the cylinder a
which it thus tends to keep cool.
The explosive engine and air pump are preferably so arranged that by fixing a
detachable handle on the fly wheel (when one is employed or a lever when one is
not) the air pump 6 can be worked for the purpose of initially charging the
receiver c.
The compressed air in the receiver may be used not only for the initial explosion
of the gas but for all explosions as the gas engine not having to produce a rotary
motion but only a reciprocating one may operate after the manner of some steam
pumps the air and gas admission valves being operated partly by a tappet motion
and partly by the pressure of air from the receiver.
A valve arrangement for supplying the compressed air to the explosive cylinder
for producing the compression charge (and thus saving the engine the work of
compressing on its return stroke) is indicated in Figs. 6, 7 and 8 in which a piston
valve 16 reciprocated by some moving part and having a regulated stroke works in
a casing 17 preferably cylindrical situated beneath or near to the cylinder a. The
rod of the piston valve 16 also carries a loose sleeve or muff 18 and said rod is
provided with a head 19 adapted to engage with the muff.
A gas supply passage 20 and, air supply passage 21 communicates with this
casing 17. When the piston valves 16 and 18 are in the position shown in Fig. 6
both of these passages are.closed but upon the valve 16 being drawn to the left the
gas passage 20 is first opened the muff 17 not being moved so that a charge of gas
is drawn in to the space between the piston valve and muff the position being that

page_text: shown in Fig. 7. Upon the valve 16 being drawn further to the left the muff is
moved by the head 19 of the valve rod and the gas passage is closed while the
valve 16 opens the compressed air passage 21 leading from the receiver as shown
in Fig. 8 the rush of compressed air taking the charge of gas out from the space
between the valve and muff (which may be regulated to contain a specified
quantity) and carrying it into the cylinder a the return stroke of the piston
valve 16 closing the gas and air passages 20 and 21. These passages would be
provided with check valves.
When an explosive engine operating in the ordinary manner is running and
charging the receiver c the pressure of air in the receiver may be made to operate
a valve controlling the engine and the arrangement may be used alone or in
conjunction with a centrifugal governor.
Such an arrangement is illustrated in Fig. 4 in which represents a pipe leading
from the receiver, g a diaphragm operating the pivoted lever / which is held against
the pressure of the diaphragm by an adjustable spring w, and i is the exhaust
valve of the explosive engine operated in the usual manner by a lever; and cam k.
When the pressure from the receiver passes a predetermined limit the lever h is
adapted to be forced out under the spindle of the exhaust valve i when said spindle
has been lifted by the end of the pivoted lever j. When the lever his thus
brought under the end of the spindle the exhaust valve i will be unable to return
and the explosive engine at the next stroke will draw in air through the exhaust
valve instead of drawing gas and air through the gas valve and air valve
respectively and thus no explosive mixture will be made in the cylinder and no
firing take place and the engine be moderated in its speed.
When the pressure of air on the diaphragm decreases the spring we will draw back
the lever h releasing the exhaust valve and the ordinary cycle of the engine will
again take place.
It is obvious that the lever h may be made to retain the gas valve and prevent it
from lifting with the suction stroke of the engine and as air only then passes
through the air valve the speed will be controlled.
The arrangement described may also be used without a receiver c. The engine
operating a small air pump in lieu of centrifugal or inertia governors and in some
cases I prefer so to employ it.
As the duty of the explosive engine is to keep the receiver charged thus
maintaining a pressure and volume of air to work the air engine it follows that if
the air engine is doing light work the pressure in the receiver will rise and the load
upon the gas engine increase and unless some provision were made the receiver
would burst or the gas engine be pulled up and therefore it is proposed to employ
a relief arrangement which may be a separate valve or made in conjunction with
the valves of the air compressor 6 as illustrated in Fig. 5 in which the inlet valve 5
of the air pump chamber is controlled by a diaphragm 6 in the passage 7 leading
from the exit valve 8 to the receiver c. When the pressure in the passage 7 rises
above a predetermined limit the diaphragm 6 forces down the pivoted lever 9 which
pressing on the pin 10 of the trip lever 11 forces it down against the pull of the
spring 12 which is provided with a roller working along the length of the arm 13 of
the lever 11 thus bringing the parts into the position shown in Fig. 54 in which it
will be seen that the roller and spring have moved from the outer end of the arın 13
to the inner end of same and the arm 14 of the lever 11 has been brought under
the end of the spindle of the inlet valve 5 at one of the moments when it is raised
by the upward stroke of the piston thus preventing it from falling with the result
that the air drawn into the cylinder b is forced out again by the inlet passage and
no pumping takes place the explosive engine running light until the pressure in the
receiver falls and the arm 14 is removed from the spindle of the valve 5. The
object of altering the position of the pull of the spring on the arm 13 is to prevent
the lever 14 being withdrawn directly the pressure in the receiver falls to the point
at which it first operates the relief arrangement, as the position the spring occupies
will require a greater pull on the lever arm 13 to withdraw it and the pressure in

page_text: the receiver will thus have an opportunity of falling several pounds before the
relief arrangement is released, and the gas engine still running through the pump
causes fresh air to be supplied to the receiver. The receiver c would be provided
with the ordinary safety valve.
Figs. 9 and 9 represent diagrammatically the arrangement of parts where the
above described means are employed in a vehicle and where the air engine dis
caused to drive directly onto the axle of the vehicle.
Figs. 10 and 10^ represent a suitable arrangement where the axle is driven by
means of worm gearing contained in a casing such as 22 the receiver c being
arranged in the form of tubular chambers placed above and below the main axle
so that a low centre of gravity is obtained, or said receiver may be in the form of
a coil or in other suitable forms. It should be also understood this applies also to.
the other parts and features of my invention which I have illustrated only for the
purpose of enabling my invention to be fully understood but which particular
constructions I do not desire to limit myself to.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is :-
1. In the propulsion of road or other vehicles an arrangement of parts whereby
an explosive power engine is caused to operate an air compressor charging a
receiver supplying compressed air to an engine which communicates its power to
the apparatus to be driven.
2. In the propulsion of road or other vehicles or apparatus an arrangement of
parts whereby a pressure of air is made to operate a valve controlling the explosive
engine and so to regulate its speed.
3. In the propulsion of road or other vehicles or apparatus an arrangement of
parts including a relief device in the air pump or compression chamber or between
it and the receiver which is operated by the pressure of air in the receiver when it
reaches a determined point so that the explosive engine runs light until the
consumption of air by the air engine reduces the pressure when the relief device.
ceases to be operated and fresh air is pumped into the receiver.
4. In the propulsion of road or other vehicles or apparatus an arrangement of
parts whereby the heat of the explosive engine is utilized to warm the exhaust
valves and surrounding parts of the air engine and the cold produced by the air-
engine is caused to cool the cylinder and heated parts of the explosive engine.
5. In the propulsion of road or other vehicles or apparatus an arrangement of
parts whereby the compressed air in the receiver can be employed to obtain the
pressure in the explosive engine of the explosive charge of gas and air such
arrangement being adapted not only for the initial explosion but for successive.
explosions during the working of the engine.
Dated this 27th day of May 1896.