IMPROVEMENTS IN CAS ENGINES
Year: 1879

page_text: LETTERS PATENT to Charles Emmet and John James Cousins, both of Leeds,
in the County of York, for the Invention of "IMPROVEMENTS IN CAS
ENGINES."
Sealed the 19th December 1879, and dated the 10th October 1879.
PROVISIONAL SPECIFICATION left by the said Charles Emmet and John
James Cousins at the Office of the Commissioners of Patents on the 10th
October 1879.
CHARLES EMMET and JOHN JAMES COUSINS, both of Leeds, in the County of
York. "IMPROVEMENTS IN GAS ENGINES."
Firstly. Our improvements have reference and are applicable to gas engines of
small power.
We employ a sliding inlet valve for the purpose of controlling the admission of
gas and air. This slide valve is also provided with a chamber carrying a travelling
or moving light. When the valve is in its highest position air and gas are by the
motion of an ordinary piston drawn into a cylinder. The valve in falling simul-
taneously shuts off the supply of air and gas, and the travelling light coming
opposite the port leading into the cylinder fires the explosive mixture thereiu
contained, whereby the piston is caused to travel and movement therefrom trans-
mitted through crank and connecting rod to fly wheel shaft. The sliding valve is
actuated by a stepped cam fitted on to the fly wheel shaft, and traversed backwards
and forwards by the action of a governor for the purpose of regulating the cut off*
and admission of air and gas, which is necessary in accordance with the power
required to be obtained from the engine. By this arrangement a proper mixture
of air and gas is obtained regardless of the point of cut off; also the engine runs
with great regularity. The slide valve in its movement downwards dips into a
reservoir of oil. A film or coating of oil adheres to the valve in its upward move-
ment, lubricating its surface and that of its case or cover.
Secondly. We admit a regulated quantity of water into the cylinder previous to
or simultaneously with the explosion. The explosion forms this into steam and
lubricates the cylinder.

page_text: Thirdly. The steam and products of combustion leaving the cylinder at a high
temperature through an ordinary lifting exhaust valve actuated by a cam on the
crank shaft are condensed in a coil of pipes provided at the outlet with an ordinary
lifting or rubber valve. Advantage is thus taken of the partial vacuum formed in
the cylinder after the explosion, and when the crank is on or passing the top
centre; also of the vacuum formed in condenser by difference of temperature of the
cylinder and atmosphere. The exhaust valve being open and inlet closed a vacuum
is thus formed under piston, assisting it on its downward stroke.
Fourthly. In gas engines of greater power than the hereinbefore described we
by preference employ a double beat drop valve, and in combination with this is
provided a mixing apparatus, which also serves to regulate the supply of gas and
air; a supplementary lighting valve is also provided. The object of the double
beat valve being that it may not be lifted by the vacuum whilst the piston is on
the down stroke; also that the heat of the explosion may not reach the packing
surrounding the valve spindle.
In gas engines of this class we by preference employ a single acting pump to the
side of the main cylinder; this is actuated by a crank on the fly wheel shaft. The
pump is fitted with ordinary inlet and outlet valves. The port leading to the inlet
valve is fitted with regulating taps for the proper admission of air and gas. This
pump feeds a receiver placed under the main cylinder, which is sufficiently large to
contain a charge capable of driving the engine, say about five or six revolutions.
The receiver is fitted with a safety valve, so that if the pressure exceeds the set
pressure the overplus may flow back into the pump. From the receiver the
mixture is led to the double beat inlet valve, the valve being in this case without
the air and gas mixing passages. A small lighting valve is also provided. Both
the inlet and lighting valves are actuated by the hereinbefore described sliding
cam. By making the lift of the lighting valve greater than that of the inlet valve
ensures the inlet valve being closed before the lighting valve drops a sufficient
distance to fire the mixture.
33
"
Further, by this arrangement it is easy to construct large engines without any
difficulty in starting them as the receiver contains a charge of gas, and all that is
necessary in starting the gas engine is to "bar or pinch" it into the proper
position when the cylinder becomes full of the mixture, and the light being allowed
to fall fires the mixture and starts the engine.