Improvements in Gas or Oil Motor Engines.
Year: 1889

page_text: Date of Application, 28th Aug., 1889
Complete Specification Lelt, 24th May, 1890-Accepted, 28th June, 1890.
PROVISIONAL SPECIFICATION.
Improvements in Gas or Oil Motor Engines.
I, CHARLES FRANCIS ADOLPHUS MCALLEN, of 121, Murdock Road Handsworth,
Staffordshire, Mechanical Engineer, do hereby declare the nature of this invention to
be as follows:-
This invention relates to gas or oil motor engines, and comprises the improvements
hereinafter described, the object being the construction of a gas or oil motor engine
with a single acting working cylinder in which an explosion of the combustible
mixture will be obtained at every revolution of the crank shaft and the expansion of
the charge continued in the cylinder to a greater volume than the original volume
before compression.
In carrying out this invention I provide an exhaust opening preferably in the body
of the cylinder situated somewhere about midway between the extreme forward and
extreme backward positions of the back of the piston, and this exhaust passage com-
municates with a pump operated by the engine so as to work in combination therewith,
so that the following cycle of operations will be performed in the working cylinder at
each revolution of the crank shaft, that is to say :- During about the first half, more
or less, of the back stroke of the piston the remaining products of the combustion of
the previous charge are by the pump withdrawn from the working cylinder the space
which they occupied being supplied with combustible mixture entering at the back
end of the cylinder following up the products of combustion towards the exhaust
passage as they are withdrawn therefrom; the explosive mixture is then compressed
by the piston completing its back stroke, the compressed charge is then ignited, and
the piston moved forward by the explosion through about the whole of its stroke, so
that the expansion of the charge is continued to a greater volume than the original
volume before compression; the said exhaust passage then opens and the products of
combustion escape therethrough and through a valve or slide, except what little remains
at about atmospheric pressure, which is withdrawn by the pump and the cycle of
operations continued as above described.
The said pump is by preference single acting and it may very conveniently be
arranged to work horizontally immediately beneath the working cylinder and operated
from the crank pin, on to which the connecting rod from the working piston is con-
nected, by employing a two armed or bell cranked lever underneath the crank shaft
to one arm of which the pump piston or plunger is connected by a connecting rod or
links, the other arm of the said lever being similarly connected to the crank pin, so
that, as the crank pin revolves, the said lever will oscillate and the pump plunger move
to and fro for the purpose above described. The said exhaust passage from the working
cylinder is by preference arranged to communicate directly with the pump cylinder
by a side opening which is closed by the pump plunger a little before and when it
reaches its extreme backward position; and the position of the lever fulcrum and the
lengths of the arms of the lever and their angular positions relatively to each other
and to the line of motion of the pump plunger are so arranged, that the pump plunger
will move forward very slowly at the commencement of its stroke so as to maintain
the exhaust passage closed whilst the working piston is moving forward and until the
working piston has almost completed its forward stroke. The pump plunger then
commences to uncover the exhaust passage when the products of combustion imme
diately pass therethrough and through the pump cylinder and escape through a suitable
self-opening or other valve in the back end of the pump cylinder which closes when
the pressure of the remaining products of combustion in the cylinder and pump fall
to about the atmospheric pressure.
As the forward motion of the pump plunger
continues it increases in velocity and draws the remaining products of combustion

page_text: from the working cylinder into the pump cylinder the said products of combustion
being followed up by the combustible mixture for the next explosion entering at the
back end of the working cylinder through a suitable valve or slide. At the same
time the working piston is making its backward stroke and when it has moved say
about half way it covers the exhaust outlet and the pump plunger will then have
reached its extreme forward position. The working cylinder now contains an uncom-
pressed charge equal to about half the contents of the cylinder plus the compression
space. The pump plunger now continues to move backwardly and drive the products
of combustion out of the pump and at the same time the working piston completes its
back stroke and compresses the charge ready for the next explosion.
By increasing or diminishing the capacity of the pump cylinder relatively to the
working cylinder the engine can be constructed so as to take in any required quantity
of the combustible mixture and so obtain any desired expansion of the charge in the
cylinder to a greater volume than the original volume before compression.
The means employed for igniting the charge may be similar to those used in other
gas or oil motor engines as they form no part of this invention.
Dated this 27th day of August 1889.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Gas or Oil Motor Engines.
1. CHARLES FRANCIS ADOLPHUS MCALLEN, of 121, Murdock Road, Handsworth,
Staffordshire, Mechanical Engineer, do hereby declare the nature of this invention
and in what manner the same is to he performed, to be particularly described and
ascertained in and by the following statement :-
This invention relates to gas or oil motor engines, and comprises the improvements
hereinafter described, the object being the construction of a gas or oil motor engine
with a single acting working cylinder in which (when the governor is not operating)
an ignition and combustion of the gaseous mixture will be obtained at every revolution
of the crank shaft and the expansion of the charge continued in the cylinder to a
greater volume than the original volume before compression.
On the accompanying drawings Fig. 1 represents in sectional side elevation a gas
motor engine constructed according to this invention; Fig. 2 is a plan and Fig. 3 is
a cross section of the same; Figs. 4, 5, 6 and 7 are diagrams illustrating the action of
the engine as hereinafter described.
The same letters of reference indicate the same parts in all the figures of the
drawings.
a is the working cylinder mounted upon a suitable base carrying the other
working parts of the engine. In the cylinder a there is the usual trunk piston a¹
connected by the connecting rod c to the crank pin d. This cylinder has two ports,
an inlet port e for the gaseous mixture provided with a spring valve opening
inwardly, and an exhaust port in the body of the cylinder situated about midway
between the extreme forward and backward positions of the back of the piston a.
The exhaust passage g communicates with the pump (arranged in this case below
the working cylinder) provided with a plunger h which receives motion from the
crank pin d through the connecting rod i, bell crank lever j, and connecting rod k.
The bell crank lever j oscillates about the fixed fulcrum j¹, its shorter arm is connected
to the crank pin d by the connecting rod i and its longer arm is connected to the
pump plunger by the connecting rod k. The position of the bell crank lever
fulcrum and the lengths of the lever arms and their angular positions relatively to
each other and to the line of motion of the pump plunger are by preference arranged
as shewn on the drawings so as to obtain different velocities of the pump plunger at
certain periods of one revolution of the crank shaft as hereinafter described. The
exhaust passage g communicates directly with the side of the pump a short distance

page_text: from the back end thereof so as to be closed by the pump plunger a little before and
when it reaches its extreme backward! position and for a short period after the pump
plunger has commenced to move forward again. At the back of the pump is the
exhaust outlet furnished with the outwardly opening valve m which is weighted by
a spring to slightly above atmospheric pressure. o is the air inlet to the usual
mixing chamber p at the back of the valve f and q is the passage for the gas which
enters the mixing chamber through numerous small openings in the wall of the
mixing chamber so as to impinge on the air and thoroughly mix therewith when the
working cylinder is taking in a charge. Similar micans may be employed for igniting
the charge as are used in other gas or oil motor engines; on the drawings I have
shewn the usual igniting tube a but this forms no part of this invention. Nor do the
means for governing the gas supply form any part of the invention and the same
being well understood require no description here. This being the arrangement of
the parts the cycle of operations during one revolution of the crank shaft is as
follows:-
Assuming an ignition to have taken place the increase of pressure and expansion
resulting from the combustion of the charge drives the piston a' forward the pump
plunger meanwhile moving backward until the piston a' has moved through about
half its stroke (see Fig. 5) when the pump plunger having completed its back
stroke commences to move forward again but at a much slower rate of speed than the
piston a¹. It will be seen by Fig. 6 that the pump plunger h¹ maintains the exhaust
passage g closed until the working piston has almost completed its forward stroke
when the pump plunger will commence to uncover the exhaust passage and the
products of combustion will immediately pass therethrough and through the pump
cylinder and its exhaust valve m which closes when the remaining products of
combustion in the cylinder and pump fall to about the atmospheric pressure. As the
forward motion of the pump plunger continues it increases in velocity and when it
has reached its extreme forward position (see Fig. 7) it has drawn nearly the whole
of the remaining products of combustion from the working cylinder into the pump.
At this point the piston a¹ in moving back has just closed the exhaust passage g.
The space at the back of the piston a¹ is now filled with an uncompressed charge of
gaseous mixture ready for the next ignition and which has entered by the port e and
followed up the products of combustion as they were being withdrawn by the pump.
This uncompressed charge is equal to about half the contents of the cylinder plus the
compression space. The pump plunger and the piston now continue to move back-
wardly, the former driving the products of combustion out of the pump through the
valve m and the latter compressing the charge (see Fig. 4) which, when the crank
has turned its back centre, is ignited as before and the piston moved forward through
about the whole of its stroke so that the expansion of the ignited compressed charge
is continued to a much greater volume than the volume before compression. In
practice I find that I obtain very good results when the charge is compressed to one
fourth its original volume and then expanded to twice its original volume, and the
engine illustrated by the accompanying drawings is thus proportioned.
It will be seen that the cycle of operations is performed in one revolution of the
crank shaft and a working stroke made every revolution.
By increasing or diminishing the capacity of the pump cylinder relatively to the
working cylinder, the engine can be constructed so as to take in any required quantity
of the combustible mixture and so obtain any desired expansion of the charge in the
cylinder to a greater volume than the original volume before compression.
Two or more cylinders and pumps may be arranged to work on to the same crank
shaft so as to form a coupled engine.
It will be evident that in the engine above described, as in other gas engines,
inflammable oil vapour can be used instead of gas.
The accompanying drawings illustrate what I consider to be the best way of
carrying my said invention into practice but it is to be understood that the invention
is not limited to the precise details herein before described and illustrated as the same
may be varied without departing from the nature of my invention; for instance

page_text: h
sliding or other valves operated by cams might be substituted for the spring valves e
and m, and the passage connecting the cylinder a to the pump might be controlled
by a valve instead of by the piston a' and plunger h¹.
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. In a gas or other inflammable vapour motor engine having a working cylinder
and a pump in connection therewith for exhausting the products of combustion,
moving the pump plunger relatively to the working cylinder piston and arranging the
passage from the working cylinder to the pump in the manner substantially as herein-
before described, so that the pump plunger during about the first half more or less of
the instroke of the piston exhausts from the working cylinder the products of
combustion which remain after the relief of pressure and simultaneously draws the
uncompressed charge into the working cylinder, and at every revolution of the crank
shaft there is in the working cylinder and at the same side of the piston ignition and
combustion of charge, then expansion of the ignited charge to considerably more than
its original volume before compression, then relief of pressure followed by exhaustion
of the remaining products of combustion and simultaneous indrawal of the fresh
charge, and finally compression of charge, substantially as hereinbefore described.
2. In a gas or other inflammable vapour motor engine of the kind denoted by the
first claim, the arrangement of the rods and hell crank for working the pump plunger
from the crank shaft in the manner substantially as hereinbefore described and
illustrated by the accompanying drawings.
3. Gas or other inflammable vapour motor engines substantially as hereinbefore
described and illustrated by the accompanying drawings.
Dated this 23rd day of May 1890.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.