IMPROVEMENTS IN GAS MOTOR ENGINES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by the said Charles Grantley Beechey
at the Office of the Commissioners of Patents on the 18th March 1882.
CHARLES GRANTLEY BEECHEY of Liverpool in the County of Lancaster Engineer,
"IMPROVEMENTS IN GAS MOTOR ENGINES "
The primary object of my Invention is to remove the whole of the products of
combustion from the cylinder of a gas motor engine after each explosion and at
the same time provide a sufficient space or clearance behind the piston when at the
end of its instroke to contain the charge of compressed combustible mixture for
the next explosion; and my Invention for this purpose essentially consists in
displacing by a small charge of combustible mixture the products of combustion
which the working piston is unable to drive out of the cylinder.
My Invention further consists in equalizing the rotary motion of the crank shaft
of the engine by forming a partial vacuum behind the working piston and the com-
pression piston during the outstrokes so as to aid the momentum of the fly wheel
during the instrokes.
One manner in which my improvements may be carried into effect is as follows:-
At any convenient position relatively to the working cylinder, but for economy in
construction by preference in front of it, I place a compression cylinder the piston
of which reciprocates with the working piston. The combustible mixture is
supplied to the compression cylinder by means of a suitable port and valve, and a
long port or passage conducts the mixture in manner hereinafter described from
the compression cylinder to the working cylinder. At the rear end of the working
cylinder is a chamber into which a cylindrical extension of the working piston
enters towards the end of the instroke and a tube or snout projects into the said
chamber from the back. Behind the chamber is a slide valve containing the ports
for the supply of the combustible mixture to the working cylinder and this valve
may also carry the burner or burners for exploding the charge or the combustible
mixture may be admitted by a separate valve.
n •

page_text: Supposing the pistons to be at the end of their instroke just before an explosion,
the chamber will contain its charge of compressed combustible mixture and a small
quantity of combustible mixture in a highly compressed state will be contained in
a clearance space of the compression cylinder. When the explosion takes place in
the working cylinder the two pistons are driven forward. During the first part of
this outstroke the compressed mixture in the compression cylinder re-expands but
the remainder of the stroke in this cylinder is in partial vacuum. When the out-
stroke is completed the exhaust valve opens and the fly wheel aided by the partial
vacuum in the compression cylinder brings back the pistons. The products of
combustion are for the main part expelled in this instroke by the working piston
through the exhaust. When during this instroke the partial vacuum in the com-
pression cylinder is spent which will be the case when the piston is within (say)
about 10th of completing the stroke the combustible mixture in this cylinder will
pass down the long port or passage before referred to and enter the explosion
chamber through the tube or snout and drive out the remaining products of com-
bustion through the exhaust the process being facilitated by the tortuous narrow
passage formed by the tube and the cylindrical extension of the piston. The
exhaust valve then closes. The momentum of the fly wheel then causes the pistons
to make an outstroke the working piston doing so in partial vacuum while the
compression piston draws into the compression cylinder a fresh charge of com-
bustible mixture. The strength of this mixture may be made to vary by the
governor. Upon the next instroke of the pistons caused by the momentuin of the
Hy wheel aided by the partial vacuum in the working cylinder the charge in
the compression cylinder is compressed until the piston is about half way down the
cylinder when communication is made between the two cylinders and the mixture
then passes by the long port, slide or other valve and tube or snout into the
explosion chamber, the compression being then completed in both cylinders. But
just previous to the pistons completing their instroke the communication between
the cylinders is cut off so that by the completion of the stroke of the compression
piston an excess pressure of the mixture therein is obtained to supply the igniting
burner at greater pressure than that in the working cylinder whereby all risk of
this burner being blown out by the pressure in the working cylinder before igniting
the charge is prevented. Before the explosion an amount of combustible mixture
in a highly compressed state is left in the clearance space of the compression
cylinder and when expanded displaces the products of combustion upon the next
instroke in the manner already described. The same cycle of operations is then
repeated. The clearance space in the compression cylinder is of such capacity as
to contain combustible mixture in a compressed state which is just sufficient to fill
the explosion chamber in an uncompressed state and replace the exhaust products
so that no combustible mixture would escape by the exhaust.

page_text: "
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Charles Grantley Beechey in the Great Seal Patent Office on the
18th September 1882.
CHARLES GRANTLEY BEECHEY of Liverpool in the County of Lancaster Engineer
IMPROVEMENTS IN GAS MOTOR ENGINES
"
The primary object of my Invention is to remove the whole of the products of
combustion from the cylinder of a gas motor engine after each explosion and at
the same time provide a sufficient space or clearance behind the piston when
at the end of its instroke to contain the charge of compressed combustible mixture
for the next explosion so that a greater or less charge of explosive mixture can be
supplied to the said space or clearance without being affected by the exhaust
products as in the gas motor engines now ordinarily constructed; and my Invention
for this purpose essentially consists in driving out and replacing by a small charge
of combustible mixture the products of combustion which the working piston is
unable to drive out of the cylinder.
My Invention further consists in equalizing the rotary motion of the crank
shaft of the engine by forming a partial vacuum behind the working piston and
the compression piston during the outstrokes so as to aid the momentum of the fly
wheel during the instrokes.
One manner in which my improvements may be carried into effect is as
follows: At any convenient position relatively to the working cylinder, but for
economy in construction by preference in front of it, I place a compression
cylinder the piston of which reciprocates with the working piston. The com-
bustible mixture is supplied to the compression cylinder by means of a suitable
port and valve, and a long port or passage conducts the mixture in the manner
hereinafter described from the compression cylinder to the working cylinder. At
the rear end of the working cylinder is a chamber into which a cylindrical
extension of the working piston enters towards the end of the instroke and a tube
or snout projects into the said chamber from the back. Behind the chamber is a
slide valve containing the ports for the supply of the combustible mixture to the
working cylinder and this valve may also carry the burner or burners for exploding
the charge; or, as I prefer, the combustible mixture may be admitted by a separate
valve.
The accompanying drawings represent a gas motor engine constructed according
to my Invention Figure 1 is a longitudinal vertical section, Figure 2 a horizontal
section and Figure an end view of the engine. Figure 4 is a transverse section
partly through the gas and air supply valve and partly through the valve which
admits the explosive mixture to the working cylinder.
The pistons are shewn in Figure 1 only. The engine makes one explosion to
every two outstrokes of the working piston. A is the working cylinder with a
chamber A' at the rear end thereof. B is the working piston. C is the com-
pression cylinder placed in front of the cylinder A, and D is the compression piston
which reciprocates with the piston B; the cylinder C may however be placed in
any suitable position relatively to the cylinder A. C' is a clearance space at the
rear of the cylinder C. E is a side shaft worked by gearing from the crank shaft
of the engine and fitted with a centrifugal governor (shewn at X' Figure 2).
F (Figure 4) is the gas supply pipe and G the air inlet; the gas and air mix in the
box or chamber H. I is the valve by which the mixture of gas and air are
supplied to the engine; this valve is worked by a lever L which is actuated by a
stepped or conical cam M this cam being carried by a boss N free to be slid along

page_text: a key O on the shaft E by means of the governor so that according to the position
of the governor one or another of the steps of the cam M acts upon the lever L;
the valve I is thus opened at the commencement of each alternate outward stroko
and closed at an earlier or later portion of that stroke according to the speed of
the engine and the amount of explosive mixture admitted to the engine is thereby
regulated. P is the valve for admitting the explosive mixture as hereinafter
described to the working cylinder; this valve is operated by a rod Q from a
cam Q (shewn separately in Figure 5) on the side shaft E. R is a spring which
tends to keep this valve closed. S is the exhaust valve operated by a rod T and
cam T¹ (shewn separately in Figure 6) from the side shaft E. U is the slide valve
carrying the exploding light V. W is the master light. X is a long port or
passage communicating between the compression cylinder C and the valve P which
leads to the working cylinder A; this port or passage receives the explosive
mixture supplied through the valve I. Y is a cylindrical extension of the piston B
extending into the chamber A¹. Z is a tube or snout projecting into the chamber A'
from the back.
the of
The action of the engine is as follows: Supposing the pistons B and D to be at
the end of their instroke just before an explosion, the chamber A¹ will contain its
charge of compressed combustible mixture, and a small quantity of combustible
mixture in a highly compressed state will be contained in the clearance space C¹
of the compression cylinder and in the passage X. When the explosion takes
place in the working cylinder the two pistons B and D are driven forward.
During the first part of this outstroke the compressed mixture in the compression
cylinder C and in the passage X re-expands but the remainder of the stroke in
this cylinder is in partial vacuum. When the outstroke is completed the exhaust
valve S opens and the fly wheel aided by the partial vacuum in the compression
cylinder brings back the pistons. The products of combustion are for the main
part expelled in this instroke by the working piston B through the exhaust.
When during this instroke the partial vacuum in the compression cylinder C is
spent which will be the case when the piston D is within, say, about 3/10th
completing the stroke the combustible mixture in this cylinder will pass down
the long port or passage X before referred to and enter the explosion chamber A¹
through the valve P (which is temporarily opened by its cam) and through the
tube or snout Z and drive out the remaining products of combustion through the
exhaust, the process being facilitated by the tortuous narrow passage formed by
the tube Z and the cylindrical extension Y of the piston B. The exhaust valve S
then closes and also the valve P. The momentum of the flywheel then causes the
pistons B and D to make an outstroke, the piston B doing so in partial vacuumi
(the spring R or any other suitable means preventing the valve P being opened by
this vacuum) while the piston D draws into the cylinder C through the valve I and
passage X a fresh charge of combustible mixture. The quantity of this mixture
is made to vary by the governor as already explained. Upon the next instroke
of the pistons caused by the momentum of the flywheel aided by the partial
vacuum in the working cylinder the charge in the compression cylinder C is
compressed until the piston is about half-way down the cylinder when communi-
cation is made between the two cylinders by the opening of the valve P by its
cam and the mixture then passes by the passage X, valve P and tube or snout Z
into the explosion chamber A', the compression being then completed in both
cylinders. But just previous to the pistons completing their instroke the com-
munication between the cylinders is cut off by the closing of the valve P so that
by the completion of the stroke of the compression piston D an excess pressure of
the mixture therein is obtained to supply the igniting burner V (through the
passage a seen in dotted lines in Figure 1) at greater pressure than that in
the working cylinder whereby all risk of this burner being blown out by
the pressure in the working cylinder before igniting the charge is prevented,
Before the explosion an amount of combustible mixture in a highly compressed
state is left in the clearance space C₁ of the compression cylinder and in the

page_text: passage X and when expanded displaces the products of combustion upon the next
instroke in the manner already described. The same cycle of operations is then
repeated. The clearance space in the compression cylinder is of such capacity
combined with that of the passage X as to contain combustible mixture in a
compressed state which is just sufficient to fill the explosion chamber A¹ when in
the uncompressed state and when forced into this chamber to replace the exhaust
products so that no combustible mixture would escape by the exhaust.
Having now described the nature of my said Invention and in what manner the
same is to be performed I declare that I claim :-
First. Constructing gas motor engines which have a space or clearance behind
the working piston when at the end of its instroke to contain the charge of
compressed combustible mixture for the next explosion, in such manner that the
products of combustion which the working piston is unable to drive out of the
cylinder are driven out and replaced by a small charge of combustible mixture,
substantially as hereinbefore described.
Second. In gas motor engines of the kind referred to in the first claim, the
clearance or space C in the compression cylinder C to contain a small quantity of
highly compressed explosive mixture for driving out the products of combustion
remaining in the working cylinder substantially as hereinbefore described.
Third. In gas motor engines of the kind referred to in the first claim, the tube
or snout
and the extension Y of the piston B as described for the purpose of
constituting a tortuous passage to facilitate the driving out of the products of
combustion from the chamber A¹ by a small charge of combustible mixture in the
manner explained.
Fourth. Constructing gas motor engines which have a working cylinder and a
compressing cylinder and make two outstrokes for each explosion, in such manner
that in the one outstroke a partial vacuum is formed behind the working piston,
and in the other outstroke a partial vacuum is formed behind the compression
piston, these partial vacuums aiding the momentum of the flywheel during the
instrokes, substantially as herein-before described.
Fifth. Constructing gas motor engines substantially as herein-before described
and represented in the accompanying drawings.
In witness whereof I the said Charles Grantley Beechey have hereunto set
my band and seal this twelfth day of September One thousand eight
hundred and eighty two
CHARLES GRANTLEY BEECHEY. (L.S.)