Improvements in or applicable to Gas and Oil Motor Engines.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in or applicable to Gas and Oil Motor Engines.
JOHN DOUGILL, 87, Choir Street, Broughton Lane, Manchester, do hereby
declare the nature of this invention to be as follows:-
The object of this invention is to describe a motor engine, which may be advan-
tageously employed in the propulsion, of vehicles upon common roads, also for
other purposes, where the smallest amount of oscillation and vibration is desired.
The manner in which I carry my invention into effect is as follows. I employ
prefferably an horizontal cylinder of sufficient length to contain two pistons, which
move in opposite directions at the same time. Each piston is provided with a
connecting rod, and attached to a crank shaft in the usual manner. The crank-
shafts are situated near each end of the cylinder and parallel with each other, and
revolve in the same direction. I couple each crankshaft by a chain and sprocket
wheel, or any other suitable device, for the purpose of keeping the cranks in their
relative position. Each crankshaft is provided with a fly wheel, in the usual
manner. One piston is coupled to its crank pin, when at the top centre. The
other piston is coupled to its crank pin, when at the bottom centre. Thus it will
be seen that the chain and sprocket wheel, cause each crankshaft to revolve at the
same speed, and in relative positions to each other. Thus the pistons will approach
and receed from each other, at every revolution of the crankshafts. My improved
engine works upon the well known Otto cycle, a charge of combustible gas or
vapour, is introduced in the usual manner, between the pistons, as they receed
each other, and compress as they approach, this mixture is ignited, and the
expansion proppels the pistons in opposite directions. The momentum of the
fly wheels, through the meidum of the chain, cause the pistons to approach
each other, at the same time expell the products after combustion, thus the cycle
is completed. By the above means, the expanding gases acting upon each piston,
become ballanced, and relieve the engine of much vibration and oscillation.
This 29th day of January 1898.

page_text: to be performed, to be particularly described and ascertained in and by the
following statement:-
The object of this specification is to describe a motor engine, which may be
advantageously employed in the propulsion of vehicles upon common roads, and
also for other purposes, where the smallest amount of oscillation or vibration is
desired. The manner in which I carry my invention into effect is as follows, I
construct the engine with a cylinder of sufficient length, to contain two pistons
each marked (A in the drawing) and the necessary compression space (marked M
in the drawings) between them, for the reception of the combustible gases,
together with the necessary movements of the pistons, to enable them to perform
their reciprocating movements. The piston's move simultaneously in opposite
directions, approaching, and receding from each other, within the same cylinder
at every revolution of their crank shafts; (each marked d) which are situated
opposite to each end of the cylinder, and are connected to each piston by rods,
in the usual manner, each crankshaft has a fly wheel (marked b) firmly keyed
thereon. The crank shafts are coupled to each other by any suitable means.
The object of coupleing them is to ensure that they revolve at one speed, and thus
cause the pistons to reciprocate uniformly, that is, continuously approaching and
receding from each other. I couple the crank shafts as follows: To each crank
shaft is fixed a chain wheel (marked h). The crank pin of one crank shaft is then
placed at its lowest position; the other crank pin is placed at its highest position,
as shown in the drawings (Fig. 1) a chain (c) is then placed round the chain
wheels and the ends joined together so that it may revolve similar to an endless
band. The chain wheels are of equal diameter and have an equal number of
teeth (or sprockets to engage with the chain.
Both crank-shafts will then revolve simultaneously in the same direction, and
also retain their relative positions with each other. The crank-shafts are weighted
for the purpose of balancing the crank pin and the connecting rod in their rotary
movement. When this invention is employed in connection with an engine work-
ing upon the Otto cycle, the combustible gases are admitted into the compression
space between the pistons during their outward or receding movements, and
compressed, during their approaching movements. The gases are then ignited and
the expansion thereof acts simultaneously and uniformly upon each piston,
causing each piston through its own connecting rod to transmit a uniform thrust
upon its crank-pin; and the fly wheels being equal in diameter and weight, receive
the power generated in the cylinder equally: removing much of the oscillation,
which otherwise occurs in engines wherein the impact of the expanding gases
impringes on a moving piston on the one hand, and a fixed cylinder-cover on the
other.
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:-
In combination in a motor engine, a cylinder a with oppositely moving
pistons, crank shafts d d, flywheels bb, chain wheels h h, and an endless chain c,
the combined parts acting in the manner for the purposes and substantially as
herein set forth and shown.
Dated this 974h dars of Ontokon 1908