IMPROVEMENTS IN AND CONNECTED WITH MOTORS WORKED BY COMBUSTIBLE GAS VAPOUR STEAM OR COMPRESSED AIR"
Year: 1882

page_text: LETTERS PATENT to John Watts of Broad Weir Engine Works in the City
and County of Bristol and Hubert Ellis Smith also of the said City and
County of Bristol for an Invention of "IMPROVEMENTS IN AND CONNECTED
WITH MOTORS WORKED BY COMBUSTIBLE GAS VAPOUR STEAM OR COMPRESSED
AIR"
PROVISIONAL SPECIFICATION left by the said John Watts and Hubert Ellis
Smith at the Office of the Commissioners of Patents on the 16th September
1882.
JOHN WATTS of Broad Weir Engine Works in the City and County of Bristol
and HUBERT ELLIS SMITH also of the said City and County of Bristol "IMPROVE
MENTS IN AND CONNECTED WITH MOTORS WORKED BY COMBUSTIBLE GAS, VApor,
STEAM OR COMPRESSED AIR
ور
Our said Invention bas for its object to improve and simplify the construction
and increase the efficiency of Gas Motors or Motors operated by combustible Gas
and also to provide means in connection with the same by which a current of air
or gas can be created for purposes of ventilation or for other purpose the latter
means being also applicable to motors worked by Vapor, steam or compressed air
In one modification of the improved motor there are two or more cylinders pro-
vided with pistons connected to a crank or cranks on one shaft having a motion
coincident with each other. In one cylinder a mixture of air and gas or vapor is
compressed and displaced to a second cylinder in which it is ignited and power
developed The cylinders are hereinafter distinguished as the "compression
cylinder" and the "power cylinder "-The power cylinder is single acting but in
some cases the compression cylinder is required to have double action The
explosive mixture is drawn into the compression cylinder by one stroke of the
piston thereof and by the return stroke is displaced into the power cylinder and
ignited early on the return stroke.
The exhaust takes place through a port in the piston passing over a port in the
cylinder as it approaches the end of its stroke so as then to open a communication
from the back of the piston to an ejector at the exhaust outlet. Previous to

page_text: reaching the end of its stroke the port in the piston has closed to the exhaust port
and opened to a second port or passage in the cylinder having communication with
the exhaust outlet through the ejector which utilise the force due to the inertia or
impact of the exhaust gases to draw a current of air through the power cylinder
and its ignition ports and passages to clear them of the remaining products of
combustion
In some cases we dispense with the ejector and employ an exhaust Fan driven by
gearing from the Motor for the same purpose.
To admit the current of air to the power cylinder the piston rod is extended and
fitted with a second piston working in a cylinder of smaller diameter but concentric
with the power cylinder open to the atmosphere at the back end and hereinafter
termed the air cylinder-The extension of the piston passing over the port or
passage in the air cylinder when approaching the end of its stroke forms a com-
munication for the atmosphere through the space at the rear of the piston of the
power cylinder and through the ignition ports and passages to the ejector
aforesaid.
The piston of the power cylinder on its return stroke closes the openings which
it had established as aforesaid and compresses the air into a chamber at the back
end of the cylinder and receives its charge of explosive mixture from the com-
pression cylinder ready for ignition for effecting its return stroke the cycle of work
being performed in one revolution of the crank shaft and an explosion occurring at
each forwark stroke.
The supply of the explosive mixture to the compression cylinder its displacement
to the power cylinder its ignition and the supply of air for scouring the ignition
ports and passages (and it may be also that for clearing the cylinder) is effected
and controlled by a slide valve or valves This valve is provided with a passage
which opens and closes a communication to supply and cut off the explosive
mixture at the required times whereby lift or other separate valves are rendered
unnecessary.
The speed of the Motor is or may be regulated by a centrifugal Governor acting
on a valve or valves which determine the quantity of explosive mixture admitted
to the compression cylinder at each revolution of the Motor The compression
cylinder may be duplicated if desired and situated at each side of the Power
Cylinder.
The air for passing through the cylinder may be drawn from a shaft or chamber
communicating with the cylinder when the passage for air is opened as aforesaid
and thus the Engine may be utilised as a draught creator for ventilating or other
purposes.
After this manner we may utilize the power due to the inertia or impact of the
exhaust, from a steam or compressed air motor by means of an ejector connected to
the cylinder by suitable ports and passages to create a current of air or gases for
the purpose of ventilation or for heating cooling or drying purposes

page_text: SPECIFICATION in pursuance of the conditions of the Letters. Patent filed
by the said John Watts and Hubert Ellis Smith in the Great Seal Patent
Office on the 16th March 1883.
JOHN WATTS of Broad Weir Engine Works in the City and County of Bristol
and HUBERT ELLIS Smith also of the said City and County of Bristol. " IMPROVE-
MENTS IN AND CONNECTED WITH MOTORS WORKED BY COMBUSTIBLE GAS. VAPOUR
STEAM OR COMPRESSED AIR
"
Our said Invention has for its principal object to increase the efficiency of Gas
Motors or Motors operated by combustible Gas by providing means in connection
with the same by which a current of air can be created to effectually clear the
cylinder of burnt gases which current of air may if required be utilized for purposes
of ventilation or for other purposes the Invention being also in part applicable to
motors worked by vapour steam or compressed air as hereinafter explained.
In constructing a motor according to our Invention we provide two or more
cylinders each having a piston or plunger connected to a crank or cranks on one
shaft and preferably having a motion coincident with each other. In one cylinder
a mixture of air and gas or inflammable vapour is compressed and then displaced
and caused to enter the other cylinder in which it is ignited and power is thereby.
developed.
The cylinders are hereinafter distinguished as the "compression cylinder” and
the "power cylinder."
The explosive mixture is drawn into the compression cylinder by the forward
stroke of the piston thereof and by the return stroke is compressed and forced into
the power cylinder and therein ignited.
The exhaust takes place through a port in the piston coinciding with an exhaust
port in the cylinder as it approaches the end of its stroke so as then to open a
communication from the back of the piston to an ejector at the exhaust outlet.
Previous to reaching the end of its stroke the port in the piston has closed to the
exhaust port and opened to a second port or passage in the cylinder having
communication with the exhaust outlet through the ejector which utilises the force
due to the inertia or impact of the exhaust gases to draw a current of air through
the power cylinder and its ignition port to clear them of the remaining products of
combustion.
To admit the current of air to the power cylinder a communication is established
between the outer air and the interior of the cylinder which may be effected as follows.
The piston rod is extended and fitted with a second piston working in a cylinder
of smaller diameter open to the atmosphere at the one end and by a port or passage
to the power cylinder at the other end. This cylinder is hereinafter termed the air
cylinder or the air inlet. The extension of the piston passing over the port or
passage in the air cylinder when approaching the end of its forward stroke opens
the communication for the atmosphere through the space at the rear of the piston
of the power cylinder and through the ignition port and ports or passages to the
ejector as aforesaid and thereby a current of air is caused to pass through the
cylinder so as to effectually clear it, of burnt gases.
The piston of the power cylinder on its return stroke closes the communications
which it had established as aforesaid and compresses the air into the space or
combustion chamber at the back end of the cylinder which space receives the
charge of explosive mixture from the compression cylinder ready for ignition for
effecting the return stroke of the piston the cycle of work being performed in one
revolution of the crank shaft and during normal working an explosion occurring at
each forward stroke.

page_text: The supply of the explosive mixture to the compression cylinder its displacement
to the power cylinder and its ignition are preferably effected and controlled by a
slide valve or valves which is provided with a passage which opens and closes
a communication to supply and cut off the explosive mixture at the required times.
The speed of the motor is or may be regulated by a centrifugal Governor acting
on a valve or valves so as to cut off the supply of gas when the speed of the engine
becomes too great.
If found convenient gas only may be supplied to the compression cylinder which
gas on being forced into the power cylinder mixes with the air therein.
The compression cylinder may be duplicated if desired and situated at each side
of the power cylinder The air for passing through the cylinder may be drawn
from a shaft or chamber communicating with the cylinder when the passage for air
is opened as aforesaid and thus the Engine may be utilized as a draught creator for
ventilating or other purposes.
We may utilize the power due to the inertia or impact of the exhaust from a
steam or compressed air motor by means of an ejector connected to the exhaust so
as to create a current of air or gases for the purpose of ventilation or for heating
cooling or drying purposes.
And in Order that our said Invention may be fully understood we shall now
proceed more particularly to describe the same and for that purpose shall refer to
the several figures on the annexed sheets of drawings the same letters of reference
indicating corresponding parts in all the figures.
Figure 1 of the accompanying drawings represents in side elevation a gas motor
constructed according to our Invention Figure 2 is an end elevation and Figure 3
a plan of the same with the crank shaft omitted Figure 4 is a longitudinal vertical
section through the centre of the power cylinder Figure 5 a horizontal section
shewing the arrangement of the compression cylinders and the ports or passages
for conducting the explosive mixture into and from the same Figures 6 and 7 are
transverse sections taken respectively along the lines 1-2. Figure 4 and 3-4
Figure 1 and Figure 8 is a front view of the port face of the power cylinder.
Figures 9 and 10 are front and back views respectively of the slide valve for
controlling the admission of the explosive mixture to the power cylinder and
compression cylinders and figure 11 is a face view of the valve cover or back plate.
A is the bed plate or frame of the motor to which the power cylinder B and the
two compression cylinders C. C¹. are bolted, the compression cylinders being arranged
one on each side of the cylinder B.
The frame A is provided with brackets or bearings D in which the crank
shaft E is mounted and also with guides F for the piston G of the power
cylinder B.
The compression cylinders C Ct are each fitted with a plunger H which plungers
are connected together and to the piston G by a transverse. shaft axle or rod I
so that all three have a motion coincident with each other and the shaft or axle I
is connected to a crank K on the shaft E by a connecting rod L for imparting
motion to the said shaft.
+
The inner end of the piston G is provided with an extension M forming another
piston of smaller diameter fitted to work in a cylinder N arranged at the end of
the combustion chamber O-which is connected to the open end of or formed in
one with the cylinder B. The said cylinder N is at its outer end open to the
outer air and at its inner end it communicates with the interior of the combustion
chamber by means of the passage or ports V. The piston M is provided for the
purpose of admitting to the interior of the cylinder B a current of air for driving
or drawing therefrom and from the ignition port the products of combustion after
each explosion has taken place, as will be hereinafter more fully explained The
admission of the explosive mixture to the compression cylinders and to the
power cylinder and the explosion thereof is controlled and effected by means
of a slide valve P actuated by an excentric Q and rod Q' from the crank shaft E.
The burnt gases or products of combustion resulting from the explosion of the

page_text: charge in the cylinder B are exhausted therefrom through a passage or passages R
in the piston G which passage when the piston has nearly completed its outward
stroke coincides with a port or ports S in the cylinder through which port the
products of combustion pass into a tube T constituting the inner tube of an
ejector and thence into the exhaust pipe U When however the piston G has
completed its outward stroke the port S is covered by the piston G and the
passage R coincides with another port S¹ in the cylinder (as shewn in Figures 4
and 5) communicating with an annular chamber T₁ surrounding the tube T and
constituting the exterior tube or outer case of the ejector During the time that
the passage R in the piston G is moving from the port S to the port S¹ the
piston M has travelled in the cylinder N so as to uncover the port or ports V
therein and thereby established a communication between the combustion chamber O
and the interior of the cylinder B and the external atmosphere. A current of air
will consequently pass through the said combustion chamber and power cylinder
and the port S¹ into the annular chamber T¹ and carry with it the products of
combustion remaining in the cylinder and ignition port through the ejector into
the exhaust pipe U.
'
It will thus be seen that the force due to the inertia or impact of the exhaust
is employed to draw a current of air through the combustion chamber power
cylinder and the ignition port to clear them from the remaining products of
combustion.
It will also be obvious that the arrangement herein before described for clearing
the power cylinder may be utilized for ventilating apartments buildings and other
places and for drying purposes by simply making the cylinder N at the rear of
the piston M communicate with the place to be ventilated or cooled or with the
apartment containing the articles or substances to be dried instead of with the
atmosphere, when the vitiated or moist air as the case may be will be extracted
therefrom and fresh dry air enter in its place In addition to this a pipe or passage
may communicate from the place from which air is to be drawn to the chamber T
as indicated by dotted lines at T² in figure 2.
W represents the gas and air supply passages the gas entering at W' and the
air at W2 The said passages communicate with the port a in the port face b of the
power cylinder, through which port the mixture is caused to pass and travel
thence through the port c passage h and the branch pipes d d' into the two com-
pression cylinders C C¹ (as will be hereinafter more fully described) in which
cylinders it is compressed by the plungers H thereof during part of their stroke
and is then by the further motion of the said plungers forced back through the
branch pipes d d' and port e into the power cylinder B where it is compressed (by
the motion of the piston G) into the chamber O. X is a permanent gas jet for the
purpose of igniting the charge in the chamber O with which it is caused to com-
municate at the proper moment by means of a passage or ignition chamber i in
the valve P causing the charge in the chamber Oto explode and drive the piston
to the opposite end of the cylinder.
In commencing to work the motor the piston G and plungers H being at the
inner ends of their cylinders and the slide valve being in such a position as to
cause the passage h in the valve to establish a communication between the ports a
and c in the port face b, the port c communicating with the branch pipes d d'
leading to the two compression cylinders C C¹ and the permanent jet X being
lighted gas is turned on to the Engine and the piston and plungers are moved
forward in their cylinders so as to draw a mixture of air and gas through the
supply passages and ports a and c and branch pipes d d into the compression
cylinders C. C' which thereby become filled. By the time the piston and plungers
have completed their outward or forward stroke the slide valve will have been
moved by the eccentric Q into the position shewn in Figure 5 the communication
between the port a and the pert c being cut off. The piston and plungers are now
caused to make their inward stroke whereby the mixture admitted to the com-
pression cylinders C C is compressed until the slide valve is brought into a

page_text: position to establish by means of the passage h a communication between the
port c connected with the branch pipes d'd' and the port e leading to the combustion
chamber into which chamber the mixture will pass from the compression
cylinders and will by the continued inward motion of the piston be compressed
into the combustion chamber O and a portion thereof forced into the ignition
chamber i through the passages k k in the port e and valve P respectively. A
slight forward movement of the piston causes the valve to travel still further so
as to bring the ignition chamber into communication with the permanent jet X
whereupon the mixture in the chamber i is ignited. The valve then commences
to make its return stroke bringing the ignition chamber i into communication with
the port e whereupon the mixture in the combustion chamber O is ignited to drive
the piston forward or through its outward stroke thus giving motion to the
crank shaft E which will have sufficient impetus imparted thereto to effect the
return stroke of the piston and plungers when the before described operations will
be repeated continuously whilst the engine is at work, the mixture being drawn
into the compression cylinders at each outward stroke and at each inward stroke
the mixture so drawn in being compressed therein and forced therefrom into the
power cylinder ready for the explosion The products of combustion after each
explosion are exhausted from the cylinder and the ignition port and a current of
air passed through them and through the passage R in the piston G and conducted
to the exhaust pipe U in the manner hereinbefore described.
Z is a jacket which may be provided for the circulation of water for cooling.
The motor may be provided with a centrifugal governor for regulating the
supply of gas in order to regulate the speed of the motor by operating a valve m
in the gas supply pipe W.
By providing the exhaust passage of steam or compressed air engines with an
ejector nozzle like that at T surrounded by a chamber like that at T with a
passage thereto as at T2 leading to a room or other place from which air is to be
drawn on the exhaust blowing through the ejector nozzle air will be drawn from
the room or other place through the pipe T2 into the chamber T¹ and thence will
pass with the exhaust to the exhaust outlet.
If it be found that the air drawn into the power cylinder as aforesaid be
sufficient to form with the gas the explosive mixture then gas alone may be drawn
into the compression cylinder or cylinders and forced therefrom into the power
cylinder to mix with the air therein and form with it the explosive mixture.
Having now described and particularly ascertained the nature of our said
Invention and the manner in which the same is or may be used or carried into
effect we would observe in conclusion that we do not limit ourselves to the precise
details herein before described and illustrated in the accompanying drawings as the
same may be varied without departing from the nature of our Invention for example
the passage for air to the cylinder could be an opening covered by a valve which
would be lifted by a tappet or by other convenient means at the time when the
air is to be drawn through the cylinder as aforesaid. What we consider to be novel
and original and therefore claim as the Invention secured to us by the herein-
before in part recited Letters Patent is :-
First. In gas motors or motors worked by an explosive mixture or vapour the
provision of means whereby at or towards the end of the forward or outward
stroke of the working piston a through passage or communication with the outer
air is formed at the space at the rear of the piston substantially_as and for the
purpose hereinbefore explained with reference to the accompanying Drawings.
Secondly-In gas motors or motors worked by an explosive mixture or vapour
the employment of a passage or passages constituting an air inlet at or towards the
rear of the space behind the piston of the power cylinder in combination with
ports or passages which respectively communicate with the interior and exterior
tubes of an ejector so that the inertia or impact of the exhaust is utilized to create
a current of air through the space at the rear of the piston to clear the said space

page_text: of burnt gases or products of combustion substantially as hereinbefore described
with reference to the accompanying drawings.
Thirdly-In motors worked by gas and air or other explosive mixture or vapour
the combination of the cylinder B and piston G with their ports or passages S. S¹
and R and the cylinder N and piston M all constructed arranged and operating
substantially in the manner and for the purpose herein before described and illustrated
in the accompanying drawings.
Fourthly The combination and arrangement of the compression cylinder or
cylinders (C C¹) and the power cylinder B wherein the piston and plunger or
plungers thereof are connected to one crank shaft so that their strokes are coincident
with each other substantially as hereinbefore described and illustrated in the
accompanying drawings.
Fifthly The general construction and arrangement of parts constituting the
motor to be worked by Gas and air or other explosive mixture or vapour.
substantially as hereinbefore described and illustrated by the accompanying
drawings.
Sixthly In motors worked by gas or other explosive vapour or by steam or
compressed air employing the inertia or impact of the exhaust for creating a current
of air for ventilating cooling drying or the like substantially as herein before
described.
In witness whereof I the said John Watts on behalf of myself and the said
Hubert Ellis Smith have to this our Specification set my hand and seal
this Fifteenth day of March One thousand eight bundred and eighty three.