Improvements in Gas and like Engines.
Year: 1894

page_text: Date of Application, 12th Apr., 1894
Complete Specification Left, 7th Jan., 1895-Accepted. 16th Mar., 1895
Improvements in Gas and like Engines.
I, JOSEPH FARMER, of 3 Brackley Road, Beckenham, in the County of Kent,
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to gas and other internal combustion engines of the
compression type in which a power impulse is given for every revolution of the
crank shaft.
My object is to produce a gas engine of this type, in which the difficulties
common to previous impulse every revolution engines are effectually overcome.
One great difficulty in such engines has been found to arise from the liability of the
gaseous charge to pre-ignition during compression or during the introduction of the
inflammable charge into the cylinder, and this difficulty I am enabled to overcome
by the use of my invention.
Another difficulty common to high speed engines of this class is due to the
insufficient cushioning of the piston and consequent knocking produced when the
engine runs fast. Part of my invention has as its object to overcome this difficulty
by so arranging the parts that all reciprocating pistons are kept in constant com-
pression in one direction, thus securing the continual pressure of the connecting
rod brasses against the crank pin or the continual pressure of the eccentric sheave
upon the eccentric pulley.
In an engine constructed to carry out my invention according to one method, I
arrange open ended compression and explosion cylinders, tandem fashion, vertically
one above the other, and I make the compression cylinder larger in diameter than
the explosion cylinder. In these cylinders I place trunk pistons connected together,
operating and operated from a crank shaft by a connecting rod. The upper or
explosion piston I make of suitable length to carry the necessary piston rings, and
I connect it to the lower or compression piston by a trunk turned of smaller
diameter than the explosion cylinder in order to leave an annular space always
open to the compression cylinder. The difference in area between the compression
piston and the explosion piston gives the available area of the compression pump.
On the cylinder cover of the explosion cylinder I mount a small compression pump
for gas or combustible vapour, and I operate the piston of this pump by a rod
attached to the explosion piston, and I cause this rod to be of such diameter as to
leave an annular space between it and the gas pump cylinder, which space freely
opens into the explosion space. I thus arrange three cylinders in line, the lower
being a compression cylinder intended preferably for compressing air alone, the
intermediate cylinder being an explosion or power cylinder and the upper cylinder
a gas or gaseous fuel cylinder.
At the side of the power or explosion cylinder I arrange two ports both opening
into the said power cylinder, but with the upper port of the two at such
distance from the end of the cylinder that when the piston is full up, the upper
port is covered by the piston rings. The distance between the two ports is so
arranged that the explosion piston at the port having the piston rings is deeper
than the extreme measurement outside the said ports, and the position is further
arranged so that when the power or explosion piston is at the top of its stroke the
lower port opens into the annular space between the trunk and the explosion
cylinder. The two ports open into a convenient reservoir or chamber which may
or may not be an annular chamber.

page_text: At the top of the gas pump cylinder I arrange a similar chamber or reservoir
with similar ports arranged in the same manner with regard to the gas pump piston,
and also with regard to the annular space formed by the gas piston rod.
At one side of the engine 1 arrange a valve cylinder or series of cylinders
in line with each other, and I carry in the said cylinder or cylinders a piston
valve or piston valves which I operate from an eccentric or other contrivance on
the crank shaft. I prefer to operate my piston valves, however, by a special gear
to be hereinafter described.
I arrange a port opening into the lower compression cylinder in conjunction
with a piston valve or part of my piston valve, and I cause the piston valve to
open the said port to atmosphere at the proper time to control the admission of air
to the said cylinder and also to cut off connection with the atmosphere to permit of
compression.
I likewise arrange an exhaust port opening into the explosion cylinder and
control it similarly by means of my piston valve so as to permit of exhausting at the
proper time.
I also control the admission of gas to the gas pump cylinder by means of a like
piston valve.
I arrange an air buffer cylinder as part of my piston valve so as to keep the
piston valve operating gear always in compression.
usual construction,
In the explosion cylinder I place an ignition tube of any
or I may fire my charge by any known means such as the electric spark. I
may use an open ignition tube without timing valve or I may use a timing valve.
The operation of the engine is as follows:-On the down stroke a charge of air
is drawn into the lower or air pump cylinder and a charge of gas into the upper or
gas pump cylinder. On the up stroke air is compressed into the compression
space of the air pump and into the annular space round the trunk connecting the
explosion and pump pistons. The gas piston likewise compresses its gas charge and
forces it into the side chamber or reservoir before described.
When the pistons reach the top or nearly the top of their stroke, the explosion
piston overruns the lower port leading into the chamber or reservoir on the side
of the explosion cylinder, while the said piston covers up the upper port. The
compressed air then rushes in from the annular space and fills up the said air
chamber.
Meantime gas under pressure has passed from the gas chamber under the gas
piston into the explosion cylinder, and the exhaust valve is closed. The explosion
cylinder is thus charged at first with gas alone. When the pistons move down the
lower port is first covered by the explosion piston and then the upper port is
opened to the cylinder; air then rushes into the cylinder from the air pressure
chamber and mixes with the gas already in the cylinder to form an explosive
mixture. The mixture is then ignited by the ignition tube or other means and the
piston is propelled downwards.
The power impulse is thus given at every downward stroke, and the engine
receives an impulse at every revolution. During the downward stroke the operation
of charging the gas and air pumps proceeds, and on the upward stroke the operation
of compressing and exhausting takes place.
By this invention the gas and air are not mixed together till the moment when
explosion is required, and so I entirely avoid the irregular explosion so troublesome
in ordinary gas engines.
I so arrange my piston valves that when the explosive gases or the flame come
into contact there is a free space round the piston which permits the pressure to get
quite round the valve and act on the rings in the same manner as the pressure acts
on an ordinary piston.
By my arrangement of power and pump pistons I always preserve the crank
pin brasses in a state of thrust against the crank pin, so that I entirely avoid
knocking.
Instead of operating my piston valve or valves by eccentric or other device

page_text: attached to the crank shaft I may operate from the connecting rod by means of
a bell crank and link connected at a suitable position, somewhat after the manner
of Joys valve gear.
The piston valve may also be operated from the connecting rod by a wire or
chain passed over a pulley and the piston valve in this case is kept in tension
against the wire or chain by air pressure, springs or other like device.
I may also modify my piston valve in various ways without departing from my
invention.
I sometimes arrange to compound my engine by adding a suitable low pressure
cylinder also controlled by piston valve.
Instead of admitting my air and gas as herein before described, I sometimes admit
air and gas separately on the return or up stroke, and compress the mixture into
a space at the end of the explosion cylinder. In all cases, however, I retain my
new features of, impulse every revolution; thrust in one direction; and pistou
valves so arranged as to take the full explosion pressure.
In some
cylinders.
cases reverse the functions of the compression and explosion
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents for the Applicant.
I, JOSEPH FARMER, of 3 Brackley Road, Beckenham, in the County of Kent,
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 :-
My invention relates to gas and other internal combustion engines of the com-
pression type in which a power impulse is given for every revolution of the crank
shaft.
My object is to produce a gas engine of this type, in which the difficulties
common to previous impulse every revolution engines are effectually overcome.
One great difficulty in such engines has been found to arise from the liability of the
gaseous charge to pre-ignition during compression or during the introduction of the
inflammable charge into the cylinder, and this difficulty I am enabled to overcome
by the use of my invention.
Another difficulty common to high speed engines of this class is due to the
insufficient cushioning of the piston and consequent knocking produced when the
engine runs fast. Part of my invention has as its object to overcome this difficulty
by so arranging the parts that all reciprocating pistons are kept in constant con-
pression in one direction, thus securing the continual pressure of the connecting
rod brasses against the crank pin or the continual pressure of the eccentric sheave
upon the eccentric pulley.
And in order that my invention may be thoroughly understood, I now proceed
to describe the accompanying drawings thereof, reference being had to letters and
figures marked thereon.
Fig. 1, is a vertical section of the gas engine.
Fig. 2, is a vertical section of the exhaust extension.
Fig. 3, is a plan of line A B of Fig. 1.
In an engine constructed to carry out my invention according to one method, I
arrange an open ended compression cylinder and an explosion cylinder g, tandem

page_text: fashion, vertically one above the other, and I make the compression cylinder ƒ
larger in diameter than the explosion cylinder g. In these cylinders I place trunk
pistous connected together, operating and operated from a crank shaft i by a
connecting rod j. The difference in area between the compression piston and the
explosion piston gives the available area of the compression pump.
I thus arrange
two cylinders in line, the lower being a compression cylinder intended for com-
pressing air and gas, the upper cylinder a being an explosion or power cylinder and
the lower cylinder a gas or gaseous fuel cylinder.
At one side of the engine I arrange a valve cylinder k or series of cylinders in
line with each other, and I carry in the said cylinder a piston or piston valves a,
and b, which I operate from a rocking lever attached to the connecting rod j or
other contrivance on the crank shaft i. I prefer to operate my piston valves a,
and b, however, by a special gear to be hereinafter described.
I arrange a port d opening into the lower compression cylinder fin conjunction
with a piston valve a, and I cause the piston valve a to open the said port d to air
and gas at the proper time to control the admission of air and gas to the said
cylinder and also to cut off connection with the atmosphere and gas supply to
permit of compression.
I likewise arrange an exhaust porte opening into the explosion cylinder g and
control it similarly by means of my piston valve b so as to permit of exhausting at
the proper time and of admitting the fresh charge compressed between a and b.
I arrange an air buffer piston p as part of my piston valve so as to keep the
piston valve operating gear always in compression as in Fig. 2. And I likewise
arrange a scavenger pump e below the valve cylinder k, or the functions of the air
buffer and the scavenger pump may be reversed.
In the explosion cylinder g I place an ignition tube of any usual construction,
or I may fire my charge by any known means such as the electric spark. I may
use an open ignition tube without timing valve or I may use a timing valve.
The operation of the engine is as follows:-On the down stroke a charge of air
and gas is drawn into the lower or air pump cylinder f. On the up stroke air and
gas is compressed into the compression space between the pistou valves a, and b,
into the receiver n. When the trunk pistons reach the top or nearly the top of
their stroke, the piston valves b and a overrun the ports c and d leading respec-
tively into the explosion cylinder and the compression cylinder f and allowing
the charge compressed between the pistous a and b to enter the explosion cylinder g
and firing tube; and cutting off the communication between the compression
cylinder and receiver space between the pistons a and b.
The power impulse is thus given at every downward stroke, and the engine
receives an impulse at every revolution. During the downward or explosion stroke
the operation of charging the compression cylinder f with gas and air through the
inlet g and the port d proceeds and the scavenger pump e delivers fresh air through
the piper in which is a non-return valve opening into the receiver space n, into n
and through the port c into the explosion cylinder g. The scavenger pump e thus
discharges fresh air through the receiver space between the valves a and b, thus
clearing out the products of combustion, and by this means I entirely avoid the
irregular explosion so troublesome in ordinary gas engines.
On the up stroke the products of combustion in the cylinder g pass out through
the port to the exhaust pipe at s and the mixture of air and gas is compressed by
the lower part of the trunk piston h into the receiver space n; and at the same
time the piston valve 6 opens communication between the cylinder g and the exhaust
pipe ats, while the piston valve a opens communication between fand n.and
shuts off communication between f and g; and the scavenger pump e draws a
charge of air from the atmosphere.
By my arrangement of power and pump pistons I always preserve the crank pin
brasses in a state of thrust against the crank pin, so that I entirely. avoid
knocking.
The piston valve may also be operated from the connecting rod. by a wire or

page_text: chain passed over a pulley and the piston valve in this case is kept in tension
against the wire or chain by air pressure, springs or other like device.
I may also modify my piston valve in various ways without departing from my
invention.
I sometimes arrange to compound my engine by adding a suitable low pressure
cylinder also controlled by piston valve.
In some cases I reverse the functions of the compression and explosion
cylinders.
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 1
claim is :-
1. In gas engines, the combination of the various parts of the mechanism.
substantially as herein described in the foregoing Specification and illustrated in
the accompanying drawings.
2. In gas engines, the combination of the compression cylinder f, explosion
cylinder g, crank shaft i, connecting rod j, trunk pistons h, ports c and d, with
valve cylinder k, receiver n valve rod o, piston valves a and b, scavenger pump e
and rocking lever 1, substantially as herein described and according to the
accompanying drawing.
Dated this 7th day of January 1895.
J. P. BAYLY,
18, Fulham Place, W., Agent for the Applicant.