Improvements in or connected with Gas Engines.
Year: 1892

page_text: Date of Application, 18th Feb., 1892
Complete Specification Left, 5th Nov., 1892--Accepted, 21st Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in or connected with Gas Engines.
I CHARLES WILLIAM PINKNEY of 1 Raglan Road Smethwick in the County
of Stafford Engineer do hereby declare the nature of this inventien to be as
follows:-
:-
My invention relates more especially to large gas engines wherein it is desirable
to provide means for starting them by one explosion without the repetition of
explosions necessary when the gas and air forming the explosive charge is at or
about atmospheric pressure.
According to my invention I place a pump in connection with the combustion
chamber by which I can force a strong mixture of gas and air into the combustion
chamber until a predetermined pressure is obtained (say for instance 10 lbs. to the
square inch above atmospheric pressure) and I provide in communication with the
passage by which the mixture is delivered from the pump to the combustion chamber
a passage (controlled by a valve or cock) leading to an igniter. Just before the
explosion is to occur I reduce the strength of the mixture being pumped so that it
becomes explosive at the time the desired pressure is reached. The said igniter
then causes the explosion and starts the engine by causing an impulse sufficient
for the purpose and thereafter the ordinary supply and ignition arrangements for
normal working are brought into action.
A convenient arrangement according to my invention consists of a pump with
inlet and discharge valves for drawing in the gaseous mixture and passing it
through a passage to the combustion chamber with which passage the igniter com-
municates. The inlet for the gas is preferably made through a number of
perforations around the valve seat through which air is drawn so that the gas and
air are properly mixed. The pumping is continued until sufficient of the mixture
of gas and air is forced into the combustion chamber to give the requisite pressure
the quantity of gas being reduced towards the end of the pumping to make the
mixture in the passage with which the igniter communicates explosive. A relief
valve may be situated between the inlet and outlet valves of the pump "weighted'
to open when the necessary pressure decided upon is reached and give a signal that
such pressure is reached. The cock leading to the igniter being opened the
gaseous mixture will pass into the igniter and an explosion will occur of sufficient
force to start the engine. When the engine is started the passage from the pump
and to the igniter are closed. The closing of the passage from the pump can be
effected by holding the outlet valve to its seat or a special valve may be provided
for the purpose in the passage leading into the combustion chamber. The pump
may be either single or double acting.
Dated this 18th day of February 1892.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in or connected with Gas Engines.
I CHARLES WILLIAM PINKNEY of 1 Raglan Road, Smethwick, in the County
of Stafford, Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
This invention relates more especially to large gas engines wherein it is desirable
to provide means for starting them by one explosion without the repetition of

page_text: explosions necessary when the gas and air, forming the explosive charge, is at, or
about, atmospheric pressure; but it may be used with gas engines of any size.
According to this invention I place a pump, or equivalent forcing device, in
connection with the combustion chamber, by which pump, or like device, I can
force a mixture of gas and air into the combustion chamber until there is obtained
an explosive charge of a pressure sufficient to enable the explosion of the one
charge to effect the starting of the engine (say for instance 10 lbs. to the square
inch above atmospheric pressure) and I provide, in communication with the passage
by which the mixture is delivered from the pump to the combustion chamber, or in
other suitable place, a passage (which can be controlled by a valve or cock,)
leading to an igniter. As there is already air in the combustion chamber I may at
first force in a strong mixture of air and gas and just before the explosion is to
occur reduce the strength of the mixture being pumped so that it becomes explosive
at the time the desired pressure is reached. The explosion then takes place and
starts the engine by causing an impulse sufficient for the purpose and thereafter
the ordinary supply and ignition arrangements for normal working are brought
into action.
A convenient arrangement according to this invention consists of a pump with
inlet and discharge valves for drawing in the gaseous mixture and passing it
through a passage to the combustion chamber with which passage the igniter com-
municates. The inlet for the gas is preferably made through a number of
perforations around the seat of the gas and air inlet valve so that the gas and air
are properly mixed. The pumping is continued until sufficient of the mixture of
gas and air is forced into the combustion chamber to give the requisite pressure to
enable the explosion of the one charge to start the engine.
If the mixture first
"
pumped in has been a strong mixture the quantity of gas is reduced (by partly
closing a cock on the gas supply pipe) towards the end of the pumping to make the
mixture in the passage with which the igniter communicates explosive when the
necessary pressure is reached. A relief valve may be provided it being "weighted
so as to open when the necessary pressure is reached and give a signal that such
pressure is reached. The gaseous mixture will then be ignited and an explosion
will occur of sufficient force to start the engine. When the engine is started the
passages from the pump, and to the igniter if necessary, are closed. The closing
of the passage from the pump can be effected by holding the outlet valve to its
seat, or a special valve may be provided for the purpose in the passage leading into
the combustion chamber. The pump may be either single, or double, acting.
And in order that the said invention may be fully understood I shall now proceed
more particularly to describe the best means with which I am acquainted for
carrying it into effect and for that purpose shall refer to the several figures on the
anuexed drawings the same letters of reference indicating corresponding parts in
all the figures. I do not however limit myself to the precise details which I now
describe and illustrate.
Figure 1 is a sectional elevation of the pump. Figure 2 is a plan of the same.
Figure 3 is a sectional view of the gas and air inlet valve detached. Figure 4
shews the pump in elevation attached to the combustion chamber of the engine the
said combustion chamber being shewn in section and Figure 5 is a horizontal
section through the pump, combustion chamber and ignition tube.
A is the combustion chamber of the engine, B the pump cylinder and C the
pump piston, or plunger, connected by a rod D, to a lever E, by means of which
the piston is reciprocated in the cylinder B. is a valve through which gas and
air are admitted to the pump cylinder. G is a passage leading from the interior
of the pump cylinder B to a passage H communicating with the combustion
chamber A. I is a valve between the passages G and H to prevent the explosive
mixture forced into the combustion chamber by the pump from re-entering the
pump cylinder. K is an ignition tube preferably heated by means of a Bunsen
burner contained in a chamber or chimney L. The tube K is in communication
with the passage H and is provided with a screw valve M opened and closed by

page_text: means of a hand wheel M2 for admitting, when required, the explosive mixture
from the combustion chamber into the heated tube K to explode the charge to
start the engine. N is a relief valve in the pump cylinder B which valve remains
closed until the required pressure is pumped into the combustion chamber, but
which will open and allow air and gas to escape to relieve any additional pressure
and to notify to the attendant that the charge in the combustion chamber has been
pumped to the necessary pressure.
This valve may be weighted to open only at the required pressure by a spring O
compressed more or less as required by means of a screwed plug P. To start the
engine the piston and crank of the engine are placed in position most suitable for
starting, the combustion chamber A being then full of air at atmospheric pressure.
The lever E of the pump is then raised from the position shewn by full lines in
Figure into the position indicated by the dotted line E thereby raising the
piston C in the cylinder B. By the upward movement of the piston C a mixture
of gas and air is drawn into the cylinder B the air entering by the passage Q
Figure 3 and the gas entering by the smaller passage R and small orifices in the
valve seat the mixture passing by the valve F into the chamber S and thence by
the passages G2 and G into the pump cylinder B, the said gas and air becoming
thoroughly mixed in their passage to the said cylinder. The charge of gas and
air thus drawn into the cylinder B by the upstroke of the piston Cis, by the
descent of the said piston, forced through the passage G, and past the valve I, into
the passage H, leading to the combustion chamber A, the inlet valve F, resting
upon its seat and preventing the mixture of air and gas from passing back there-
through. Another charge of mixed air and gas is then similarly drawn into the
pump cylinder and forced into the combustion chamber, this being repeated unti!
the required pressure in the combustion chamber is reached which will be notified
by gas and air under any additional pressure escaping past the relief valve into the
atmosphere or into the exhaust pipe of the engine. The combustion chamber being
thus charged to the required pressure the pumping operation is stopped and the
valve M may then be opened by means of the hand wheel M² so as to permit of a
portion of the explosive mixture from the combustion chamber entering the ignition
tube K which has been previously heated by the Bunsen flaine in the chamber, or
chimney, L, and thereby cause an explosion of the charge in the combustion
chamber which will give sufficient impetus to the piston of the engine to start
it by imparting motion to the crank and fly wheel and bring into action the ordinary
gear for operating the engine.
The piston C, of the pump B, when in its lowest position covers the passage G
by which the explosive mixture enters the said cylinder and it also presses on the
relief valve N so as to force the said valve from its seat in which position it may
be retained by means of a pin U inserted in the upper hole or holes provided in
lugs V on the pump cylinder B the said pin being over the top of the lever E so
as to prevent the said lever and consequently the piston C from being raised. By
thus keeping the relief valve open when the engine is ready to be started or while
the engine is at work, any of the explosive mixture that may leak past the valve I
into the passage G will not act on the underside of the piston, C, but will fill the
said passage G. Should any of the pressure leak past the piston C into the pump
cylinder it will escape through the relief valve N into the atmosphere, or into the
exhaust pipe of the engine. When the pump is in use for charging the combustion
chamber the piston C may be prevented from coming into contact with the relief
valve N by removing the pin U from the upper hole in the lugs V and inserting it
in the lower hole or holes W so that the underside or edge of the lever, when the
piston C is making its down stroke, will come against this pin and prevent the
piston from moving to its full extent as to drive the valve N from its seat.
Instead of using the igniter tube K for starting the engine as described the
igniter used for the ordinary working of the engine may be employed for the
purpose, in which case before the explosive mixture is pumped into the combustion
chamber the passage to the igniter is closed which may be done by forcing a

page_text: wedge X between the upper end of the lever Y and the valve Z of the ordinary
igniter so as to force the valve tightly onto its seat as shewn in Figure 4.
When sufficient pressure has been forced by the pump into the combustion
chamber A the wedge X is withdrawn whereupon the valve Z, by the pressure in
the combustion chamber and the spring a, will be removed from its seat and admit
of communication between the charge in the combustion chamber and the ordinary
ignition tube in the holder to effect the explosion of the compressed charge and
start the engine. The engine will then continue to work in the ordinary manner,
c being the cam for operating the valve Z through the lever Y.
As the ignition tube and passages leading to it may be filled with inert gas,
which would interfere with the contact of the explosive mixture with the igniter,
there may be a small passage from the outer end of the igniter tube which passage
may be opened, when the valve Z is released, so as to allow the inert gas to pass
out into a chamber, or into the outer air.
In small engines, when the crank of the engine has been placed in the most
advantageous position for starting, it is important that means should be provided
to prevent it from being moved out of this position by the pressure of the mixture
being forced into the combustion chamber and a simple arrangement for this
purpose is shewn in Figure 6 in which g is an arm or lever centred at to the
frame, or bed-plate, of the engine. To the outer, or free, end of the arm g is hinged
another lever i the front end of which lever is curved, or of hooked form, to
engage a stud (projecting from the check of the crank m) when the said crank
is in the most advantageous position for starting. The rear end of the lever i has
a recess n containing a spring o which bears on the arm, or lever, g, the said spring
being of sufficient strength to keep the end k of the lever i engaged with the
stud, on the crank until the explosion takes place. When the charge is exploded
the spring o yields by the force of the explosion acting on the crank, so as to
release the said crank, the arm g then falling to the position shewn by dotted lines.
It may be held by a spring clamp p by which it is prevented from rising.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1st. The combination, with a gas engine, of a pump, or forcing device, by which
a mixture of gas and air to form an explosive charge can be forced into the com-
bustion chamber of the engine to such a pressure that on its being ignited it will
start the engine by one explosion substantially as hereinbefore described.
2nd. In connection with a gas engine, the combination of a pump, or forcing
device, by means of which a mixture of gas and air can be forced into the combus-
tion chamber of the engine to such a pressure that on its being ignited it will start
the engine by one explosion, a relief valve which will allow pressure above that
required for the charge to escape and denote when a sufficient pressure of the
charge is attained in the combustion chamber, and means for effecting the explosion
of the charge substantially as herein before described.
3rd. The combination of parts constituting means for starting a gas engine by a
single explosion substantially as hereinbefore described and illustrated by the
accompanying drawings.
Dated this 5th day of November 1900
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.