Improvements in and relating to Motor Engines, for Vehicle and Launch Propulsion in particular.
Year: 1895

page_text: PROVISIONAL SPECIFICATION.
Improvements in and relating to Motor Engines, for Vehicle and
Launch Propulsion in particular.
WALTER ROWBOTHAM, 52, Wheeley's Road Edgbaston Birmingham in the
County of Warwick Electrical Engineer, do hereby declare the nature of this
invention to be as follows:-
In my improved engine I use one or more cylinders, open at both ends, with two
or more pistons suitably connected by connecting rods & cranks or gearing wheels
to the fly-wheel. I arrange the pistons at the end of the stroke to leave an
aperture at each end of the cylinder so that the exhausted air will escape from the
rear end & a fresh air supply enter the forward end, thus supplying fresh air &
cooling the cylinder. Sometimes to get a rapid current of air through the
cylinder, I connect an air pump, worked by the crank shaft, to the forward
aperture of the cylinder. To vapourise, I affix in the centre of the cylinder
between the two piston butts (where the full compression takes place) a coil of
wire or series of plates insulated from each other & also insulated from the body
of the engine; & to each end of the wire or series of plates, I connect a wire from
a suitable electric accumulator, primary battery or other electric generator; & in
a line, preferably above, I fix a rose or perforated nozzle to which is attached a
force-pump actuated by a governor or cams either on the fly-wheel or other suitable
wheel on the shaft. The oil or spirit is fed into the pump from a chamber by a
pipe to which is fixed a feed valve also actuated by a cam on the fly wheel or other
suitable wheel on the crank shaft. For ignition purposes, I affix in the compression
or combustion chamber a number of electric spark points which are connected up
through an induction coil to the electric generator. Sometimes I employ a
separate chamber for the coil of wire or series of plates which are used to
vapourise, & I connect it with the combustion chamber by a suitable valve.
I sometimes coat the compression or vapourising chamber with fire-clay or
indestructible porcelain, or other refractory material, to confine the heat, keep the
cylinder cool & avoid the use of a water circulation.
Dated this 27th day of November 1895.
Improvements in and relating to Motor Engines, for Vehicle and
Launch Propulsion in particular.
I, WALTER ROWBOTHAM, now of 27, Vittoria Street, Birmingham, but formerly
of 52 Wheeley's Road, Edgbaston, Birmingham in the County of Warwick,
Electrical 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 :-
This invention relates to that class of motor-engines that are worked by explosive
or combustible mixtures of air and gas or air and hydrocarbon or other oil and has

page_text: for one of its principal objects to so construct engines of this kind that they will
be specially suitable for the propulsion of road vehicles and boats and for other
propulsive purposes where extreme lightness and absence of vibration are of
importance.
Another important object of my invention is to effect the vaporization of the
oil charges by means of an electrically heated body, so arranged as to be heated
to a temperature less than that at which the combustible mixture ignites, which
is located within or forms part of the working cylinder or combustion chamber.
According to my invention the working cylinder is open at both ends and is
provided with two pistons that move in opposite directions, the explosion or
combustion chamber being situated between the two pistons and substantially at
the middle of the cylinder so that the shocks due to the explosions of the working
charges will be absorbed by the oppositely moving pistons instead of being
transinitted to the framing of the engine as is the case when the working cylinder
has only one piston. The rectilinear reciprocating movement of the two pistons
is converted into continuous rotary movement by any suitable means and an
appropriate valve is provided for admitting the charges of gas or oil to the
cylinder or combustion chamber. I also provide means whereby a current of cool
air can be caused to flow through the working cylinder to drive out the products
of combustion, to cool the cylinder and to supply the requisite charges of air for
supporting combustion. The ignition of the explosive mixture is effected preferably
by an electric sparking device or devices.
The parts of the engine that are exposed to high temperature may be provided
with refractory material such as fire-clay asbestos or indestructible porcelain so
that undue loss of heat by conduction and radiation will be avoided and the use of
a water-jacket and of water circulation may be dispensed with. The parts that
I find it most advantageous to provide with this refractory material are the
⚫ combustion chanrber and the inner ends of the pistons.
All the parts of the engine are where practicable, made tubular or hollow for
reducing the total weight of the engine as much as possible.
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 wherein I have illustrated an oil engine having one cylinder
and suitable for use with a road vehicle. It will be obvious that I may construct
the engine with two or more cylinders if found desirable.
Figure 1 is a side elevation."
Figure 2 is a plan;
Figure 3 is a transverse section on a larger scale and taken approximately
through the middle of the working cylinder.
Figure 4 is a longitudinal section of a portion of the working cylinder als
shewn on a larger scale.
Figure 5 is an elevation of one of the sparking devices 1 employ for igniting the
xplosive charges within the working cylinder.
Figures 6 to 11 illustrate various constructions of the electrically heated body.
Like letters of reference indicate similar parts in all the figures.
A is the working cylinder; A' the combustion chamber; B B are the pistons;
C the crank shafts; D is the fly wheel; and E the inlet valve for controlling the
admission of the oil charges to the combustion chamber.
The cylinder A is in the form of a comparatively long tube which is bolted or
otherwise firmly connected to angle-iron beams F affixed to the bottom of the
vehicle. To these beams are also connected plummer blocks F1 F1 in which the
two crank shafts C have their bearings. Each of the crank shafts has two
cranks CC to the former of which the pivoted piston rods B' are connected and
to the latter of which the connecting rods G are connected. The inner ends of
these connecting rods are coupled to a crank plate or disc H by a crank pin H¹.
This crank disc is mounted on a transverse shaft H2 carrying the fly wheel D.
The power may be transmitted from this shaft to the road-wheels of the vehicle by

page_text: suitable toothed gearing or by a belt passing around a belt pulley D'. During the
working of the engine the aforesaid cranks do not perform a continuous revolution
but oscillate and this oscillatory movement is converted into continuous rotary
movement by the connecting rods G and crank plate H. By these means I require
only one fly-wheel which is mounted on the shaft to which the crank plate His
keyed. I wish it to be understood however that I do not confine myself to this
manner of converting the reciprocating motion of the pistons into continuous
rotary motion as this may be effected in a variety of other ways that will be
obvious to persons of ordinary mechanical knowledge.
The inlet valve E is actuated, in the arrangement shewn in the drawings, by
means of a vertically reciprocating rod e pivotally connected at its upper end to a
rocking bar e which acts directly on the stem 3 of the valve. The lower end of
the rod e is provided with an anti-friction roller e³ which runs on the periphery of
the crank disc H. This disc is formed with a protrusion or cam piece H³ which
actuates the rod è once during each revolution of the said disc and thereby opens
the inlet valve and admits a charge of oil coming from a suitable source of supply
through the pipe E'.
Situated near the ends of the working cylinder are apertures a a which are so
disposed that they are kept covered by the pistons except at the time when the
pistons fully complete their outstroke; they are then uncovered and are put into
communication with the interior of the working cylinder. Connected with these
apertures are pipes a¹ whose lower ends terminate in trumpet mouths a² facing in
opposite directions as shown in Figure 4, so that in whichever direction the vehicle
travels a current of atmospheric air will be induced to flow through one of these
pipes and pass completely through the working cylinder and escape by the other
of the said pipes. This current of air is obtained each time the pistons complete
their outstroke and uncover the aforesaid apertures a. In this manner the
products of combustion are removed from the working cylinder and a fresh charge
of air supplied thereto and at the same time a cooling effect on the cylinder is
obtained.
Where it is desirable to obtain a more vigorous current of air through the
cylinder I employ an air pumn I (Figures 1 and 3) the piston of which is operated
from an eccentric mounted on the shaft H2. The aforesaid pump piston is
provided with air inlet valves 2 which open inwardly as the piston ascends and
allow the pump cylinder to become filled with air which is compressed during the
descent of the pump piston. This compressed air is forcibly driven through a
pipe a and injected into and through the working cylinder when the pistons B
complete their outward stroke and uncover the aforesaid apertures a.
A2 (Figures 3 and 4) is the internal coating of indestructible porcelain or other
suitable refractory material with which the combustion chamber is provided and
B' (Figure 4) is similar refractory material with which the inner ends of the pistons
are likewise provided. This material is moulded to the requisite cylindrical form
so as to tightly fit the cylinder, and that for the piston ends is made in the form
of plates
or dises which are affixed to the pistons by screws 6 or other appropriate
means. By providing the engine with the aforesaid refractory material arranged
as specified, I keep the working cylinder comparatively cool and as already stated
am able to dispense with a water-jacket. Consequently the efficiency of the engine
is greatly increased, because when a water-jacket is employed much power is
wasted in the heat absorbed by the water in keeping the cylinder cool.
JJ J are the electric ignitors which in Figures 1 to 5 consist of insulated screw
plugs, fitting into the wall of the cylinder A, and carrying at their inner ends a pair
of bent wires which project into the combustion chamber; these ignitors are
preferably arranged in circuit with the secondary winding of an induction coil,
suitable contact devices being provided and operated by some moving part of the
engine for closing the circuit of the primary winding of the induction coil to cause
sparks to simultaneously leap between the inner ends of the bent' wires of the

page_text: ignitors and explode the charge within the combustion chamber, each time the
pistons complete their inward stroke and fully compress the said charge. I do not
confine myself to the use of these ignitors, as others of different construction may
be employed. For instance the inner ends of the pistons B may have hinged
fingers (Figure 11) which are in electric connection with a battery or other source
of electric supply through the frame of the engine. These fingers are so arranged
that as the pistons complete their inward stroke they come in sliding contact with
an insulated terminal 62 which projects into the combustion chamber A¹.
K is the electrically heated body which I use to vaporise the oil, it consists of
porcelain asbestos or other refractory body in which is imbedded a wire or strip or
wires or strips of iron or other suitable metal; it may take many forms such as
I have shown and illustrated in the drawings and numbered 6 to 11-it is heated
by the passage of the electric current through the wires or metal strips the heat
being transferred by contact from the wire to the refractory material and thus
offering a larger surface to operate upon the oil-and making it possible to vaporise
a sufficient quantity of oil without having resort to high temperatures which might
explode the gases simultaneously with their generation. The electrically heated
body may be made of increased dimensions so as to fit the interior of the working
cylinder as shewn at Figure 11, and as a further variation I have here shewn the
cylinder E as it would be formed if made of metal, that is to say it is in the form
of a bobbin provided with end flanges K¹ between which, convolutions of conducting
wire K² are wound. The said wire is insulated by asbestos or other material that
will withstand the heat of the combustion chamber. The exterior of the bobbin is
surrounded by a coating or jacket K³ of asbestos or other refractory material to
retard the transmission of heat to the cylinder A. The bobbin is adapted to
tightly fit inside the cylinder A, the said coating or jacket K³ projecting somewhat
beyond the periphery of the end flanges K¹ so that they do not come into contact
with the cylinder. The conduction of heat by these flanges to the cylinder is thus
prevented. This bobbin may if preferred be made of refractory material instead
of metal.
It is preferable to so arrange the aforesaid electrically heated body that the
oil charges can be injected or showered directly onto it as shewn at Figures 3
and 4.
Instead of locating the said electrically heated body within the combustion
chamber as above set forth it may be situated within a separate vapourising
chamber connected with the working cylinder.
It is to be understood that the temperature of the electrically heated body is to
be kept below incandescence as I find that if the body be too hot the oil ignites
and partial and imperfect explosion takes place before the oil is completely
vaporised. The temperature must therefore he kept below the igniting point.
In the engine shewn in the drawings the explosion of the charge admitted to
the working cylinder takes place at the completion of each inward stroke of the
pistons.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
•
1. The combination with the combustion or other chamber or space wherein the
vapourization is effected, of an electrically heated body of metal, refractory
material or other suitable substance, heated to a temperature below the igniting
point of the oil for the purpose of vaporising, substantially as described.
2. A body capable of being electrically heated, as claimed in the preceding
claim, and consisting of one or more wires or metal strips imbedded in porcelain
or other refractory material which material is when heated by its contact with the
wire or metal strip used to vapourise the oil for the purpose and in the manner
herein before described and illustrated.

page_text: 3. An explosion engine constructed and arranged to operate substantially as
described with reference to the accompanying drawings and for the purposes-
specified.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.