IMPROVEMENTS IN GAS MOTIVE- POWER ENGINES AND IN THE MEANS FOR REGULATING AND TRANSMITTING THEIR MOTION
Year: 1875

page_text: LETTERS PATENT to Edwin Powley Alexander, of 14, Southampton
Buildings, in the County of Middlesex, Consulting Engineer and
Patent Agent, for the Invention of "IMPROVEMENTS IN GAS MOTIVE-
POWER ENGINES AND IN THE MEANS FOR REGULATING AND TRANSMITTING THEIR
MOTION."-A communication from abroad by Alexis de Bisschop,
of Paris, in the Republic of France, Engineer.
Sealed the 12th May 1876, and dated the 15th December 1875.
PROVISIONAL SPECIFICATION left by the said Edwin Powley
Alexander at the Office of the Commissioners of Patents, with
his Petition, on the 15th December 1875.
I, EDWIN POWLEY ALEXANDER, of 14, Southamption Buildings, in
the County of Middlesex, Consulting Engineer and Patent Agent, do
hereby declare the nature of the said Invention for "IMPROVEMENTS IN'
GAS MOTIVE-POWER ENGINES AND IN THE MEANS FOR REGULATING AND TRANSMITTING
THEIR MOTION," a communication to me from abroad by Alexis de
Bisschop, of Paris, in the Republic of France, Engineer, to be as
follows:
―:

page_text: which are applicable to other engines worked by explosive mixtures;
also to certain peculiar combinations and arrangements of apparatus for
regulating the working of such engines, and for transmitting their
motion to other machines, more especially in those cases where the
driven machines are required to be worked at varying speeds, and to be
frequently stopped and started as in the case of sewing machines for
example.
According to one part of this Invention which has for its object the
better and more complete utilization of the explosive force, it is proposed
to increase to as great an extent as possible the speed of action of the
explosive force of the mixture of air and gas or other explosive mixture
on the piston, and this is attained, not by increasing the number of
strokes of the piston, but by increasing the length of its stroke and
reducing its surface in the same proportions. The increase in the speed
of action of the explosive force thus obtained affords a longer expansion
of the burnt gas, imparts elasticity to the shock, and consequently
reduces the noise. The speed of action is limited only by the rapidity of
ignition or inflammation. In all direct action gas engines, that is to
say, engines not utilizing the vacuum, the relation of the course or
length of stroke to the diameter of the piston has been somewhere
about the square, but in this improved engine it is at the least twice as
great, and may even be extended to ten or more times the diameter.
By the adoption of these proportions an economical working of an
explosive mixture is obtained by applying the force of the explosion
direct by means of a connecting rod and crank which has not hitherto
been considered practicable.
Before starting the engine it is proposed to heat it artificially for a
few minutes by a small gas furnace with which it is specially provided;
and consequently when the engine is started no condensation of the
aqueous vapour produced by the explosion against the cold sides of the
cylinder occurs, and hence the piston can be made to fit the cylinder
more closely, thereby reducing the noise in working and diminishing the
expenditure of gas.
Water has hitherto been employed for modifying the temperature of a
gas engines when at work, but according to another part of this Inven-
tion it is proposed to keep down the said temperature by radiation alone

page_text: in substitution for the use of cold water, for which purpose a number of
radiating surfaces or wings are employed representing a surface about.
five times greater than the exterior surface of the cylinder.
As in the improved gas engine a long stroke is essential it is necessary
5 that the mechanical arrangement for transferring the motion of the
piston to the crank shaft shall be such as will insure perfect stability,
even when the engine is placed so as to work vertically. For this
purpose a return connecting rod is used connected at its upper end to
the sliding block of the piston rod working in vertical guides, and at its
O lower end to a single crank on the end of a crank shaft situate a
considerable distance below the said guide block. During the time the
explosion is acting the connecting rod scarcely varies in its inclination
or angle, but remains nearly parallel to the piston rod, thus lateral
friction is considerably. reduced. In lieu of the explosive mixture
5 being formed directly within the cylinder, the air and gas enter by duly
proportioned openings into two separate and distinct passages isolated
from each other, but meeting together in an opening in an equilibrium
slide valve, which opening communicates with the cylinder during the
up stroke of the piston. During the down stroke the valve rises and
O uncovers a fresh aperture for the exhaust, whilst at the same time it
closes the openings for the air and gas. This slide valve is worked by
an eccentric from the crank shaft.
In substitution for the air and gas valves hitherto employed con-
sisting of faced metal plates resting upon the bottom of the cylinder,
6 and which were attended with many inconveniences, it is now proposed
to extend considerably the length of the air and gas passages, so that
their mouths may be entirely removed from the influence of the caloric,
and may consequently be fitted with valves not as heretofore necessarily
of metal but of thin strips of india-rubber resting upon or against a
perforated smooth surface.
In cases where constant and regular work is required as in driving
pumps, fans, electric machines, and the like, a regulator will be found
useful, the work being governed by the quantity of gas introduced.
But in driving sewing machines and other machines the speed of which
is necessarily variable, whilst they are at the same time required to be
stopped and started at frequent and short intervals, it is necessary to'
adopt special driving arrangements, and if several of such machines are

page_text: to be driven from the same engine, the employment of a regulator or its
equivalent becomes indispensable. In driving a single sewing machine
for example, a double grooved pulley is employed in the said machine
mounted upon an eccentric shaft which is rocked or partially turned
more or less by the action of the ordinary treadle of the machine. One
of the two grooves receives the driving band from the engine, and the
other a second band which passes over the actual driving pulley of the
machine. When the treadle is pressed upon by the foot of the operator,
the eccentric shaft is partly turned in its bearings, and the pulley drawn
downwards more or less, thereby tightening the second band and driving
the machine, but when the pressure on the treadle is relaxed or entirely
removed, a counterweighted lever in connection with the eccentric
shaft causes the said shaft to turn slightly in the reverse direction,
thereby more or less slackening the band, and either reducing the speed
of the machine or entirely arresting its motion.
In order to increase or diminish the supply of gas according as the
machine is working or not a pair of spring gripping plates are combined
with the connecting rod of the treadle, and between these plates passes
the india-rubber tube which supplies the gas, so that the sides of the
said tube will be more or less pinched together, or throttled on the
release of the treadle, and vice versa, thus regulating the supply of gas
in accordance with the demand.
When several machines are being driven from one engine the motion
is transmitted from the pulley of one machine to that of the next, and
so on by separate bands, and should it be required to stop or start any
particular machine this can be effected without interfering with the rest
by simply acting upon its treadle as above described. The treadle
motion of each machine operates upon a cord which is connected either
directly with a gas regulator, such as above set forth, or indirectly
therewith through the cord of the preceeding machine.
In some cases the regulator is actuated from the slide valve eccentric
through a cylinder and piston, to which the admission of air is controlled
by causing it to pass through a more or less constricted aperture; or the
said regulator may be brought into operation by the centrifugal action
of revolving weights carried by spring blades mounted on rotatory discs
driven by a band from the engine.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edwin Powley Alexander in the Great Seal Patent
Office on the 14th June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWIN
POWLEY ALEXANDER, of 14, Southampton Buildings, in the County of
Middlesex, Consulting Engineer and Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifteenth day of December, in the year
of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Edwin Powley Alexander, Her special
license, that I, the said Edwin Powley Alexander, my executors, admini-
strators, and assigns, or such others as I, the said Edwin Powley
Alexander, my executors, administrators, and assigns, should at any
time agree with, and no others, from time to time and at all times
thereafter during the term therein expressed, should and lawfully might
make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an In-
vention for "IMPROVEMENTS IN GAS MOTIVE-POWER ENGINES AND IN THE MEANS
FOR REGULATING AND TRANSMITTING THEIR MOTION," a communication to me
from abroad by Alexis de Bisschop, of Paris, in the Republic of France,
Engineer, upon the condition (amongst others) that I, the said Edwin
Powley Alexander, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Scal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Edwin Powley Alexander, do hereby
declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained
in and by the following statement thereof, reference being had to the
accompanying Drawings, and to the letters and figures marked thereon,
that is to say :-
The said Invention relates to certain peculiar physical and mechanical

page_text: improvements in what are commonly known as "gas engines," and
which are applicable to other engines worked by explosive mixtures, also
to certain peculiar combinations and arrangements of apparatus for
regulating the working of such engines and for transmitting their
motion to other machines, more especially in those cases where the
driven machines are required to be worked at varying speeds, and to be
frequently stopped and started as in the case of sewing machines for
example.
According to one part of this Invention which has for its object the
better and more complete utilization of the explosive force, it is proposed
to increase to as great an extent as possible the speed of action of the
explosive force of the mixture of air and gas or other explosive mixture
on the piston, and this is attained, not by increasing the number of
strokes of the piston, but by increasing the length of its stroke and
reducing its surface in the same proportions. The reason of the increase
of work effected by this arrangement is clearly indicated on studying the
formula of "vis viva." It will in fact be found on reducing the force by
on half and increasing the speed to an equal extent, that as the speed
increases as the square the total force will be doubled. This increase
in the speed of action of the explosive force thus obtained affords a
much longer expansion of the burnt gas, imparts elasticity to the shock,
and consequently diminishes the noise in working. The speed is
limited only by the rapidity of ignition or inflammation. In all direct
action gas engines (that is to say, engines not utilizing the vacuum),
hitherto proposed the relation of the course or length of stroke to the
diameter of the piston has been somewhere about the square, but in this
improved engine it is at the least twice as great, and may even be
extended to ten or more times. It is limited only by the facility of
construction and the degree of economy to be realized. By the adoption
of this improved system an economical working of an explosive mixture
is obtained by applying the force of the explosion direct by means of a
connecting rod and crank, which has not hitherto been considered
practicable in "gas engines."
Gas engines have not properly speaking a starting gear, and on
starting certain irregularities are produced which are all the greater in
proportion as the expenditure of gas becomes weaker. The result is that
the aqueous vapour produced by the explosion becomes condensed on the
cold surfaces of the cylinder, and forms an adhesion between the piston

page_text: •
In the arrangements heretofore proposed by my foreign correspondent,
the air and gas valves were composed of a faced metal plate resting upon
a seat, and all the air and gas valves were situate at the bottom of the
cylinder. In addition to the difficulty of facing a large number of
valves and seats, this system possessed the disadvantage of producing
many irregularities by reason of the valves frequently sticking fast to
their seats, thereby modifying the conditions of the mixture. To obviate
these inconveniences it is now proposed to prolong considerably the air
and gas passages, so that their mouths may be entirely removed from
the influence of the caloric, and may consequently be fitted with valves
not as heretofore necessarily of metal, but of thin strips of india-rubber
resting upon or against a perforated smooth surface.

page_text: the operator. According as the treadle is more or less pressed upon a
greater or less eccentric motion of the pulley is obtained, thereby
tightening or slackening the second band, which imparts motion to the
actuating pulley of the machine. A counterweight restores the double
grooved pulley to its extreme point of eccentricity as soon as the treadle
is released.
.
In order to increase or diminish the supply of gas according as the
machine is working or not a pair of spring gripping plates are combined
with the connecting rod and situate between the eccentric shaft and
the treadle, the said spring plates being connected together at their
extremities by screws. One of these plates is fixed on the side next the
treadle, whilst the other is fixed on the side next the shaft. Between
the said plates is passed the india-rubber tube which conducts the gas
to the engine. The stricture or throttling of this tube is so regulated as
to enable only just sufficient gas to pass to maintain the motion of the
engine when the sewing machine is stopped.
The action of this arrangement is as follows:-The operator, seated in
front of the machine as usual, presses upon the treadle, the driving band
of the sewing machine is thereby immediately tightened, and the spring
plates which grip or pinch the india-rubber gas supply tube are
separated or drawn asunder. The sewing machine at once commences
to work, and the supply of gas is regulated by the pressure of the foot,
so that only just sufficient for the work to be done is allowed to pass
along the supply pipe. When the operator requires to stop the machine
she simply removes her foot from the treadle, whereupon the pinching
spring plates approach each other, the supply of gas is throttled and
reduced to a small amount, the eccentric shaft of the machine is turned
backwards by the action of the counterweighted lever, and the speed of
the machine is immediately reduced or its motion arrested. This
arrangement, which is most sensitive in its action, thus admits of the
speed of the machine being instantly reduced, increased, or arrested at
the will of the operator.
When several machines which are required to work intermittently are
to be driven from one engine the following arrangement is proposed:
The machines (Figure 3) are placed one behind the other, and each is
provided with a grooved pulley having three grooves in lieu of two, as

page_text: previously described. This third groove serves to transmit motion to
the next adjoining machine, and so on. All the herein-before described
arrangements remain the same for several machines as for one, excepting
that the spring plates which serve to grip or pinch the india-rubber gas
supply tube in lieu of being situate between the treadle and the
_eccentric shaft of each machine are placed in any convenient situation,
and are connected to the machines by cords, so that any one of the
machines may bring them into action independently, or all may operate
upon them simultaneously, each machine being at the same time
independent of the other. For this object the eccentric shaft of each
machine acts as a windlass the moment the spring plates are to be
operated upon by the intervention of a smaller cord, the action of which
is transmitted to the main cord. It is also proposed to employ for the
same purpose a self-acting speed regulator (Figure 4) operating by
centrifugal force. It consists of two or more blade springs fixed at
their two ends to two discs, one of which discs is fixed and the other
loose upon a hollow shaft. The regulating weights are fixed to the
middle of each blade spring, so that when the apparatus is at work the
centrifugal force tends to displace the moveable or loose disc, the move-
ment of which is transmitted to a small rod situate inside the hollow
shaft which pushes against a piece which flattens or pinches more or
less the india-rubber supply tube, and thus controls the supply of gas
according to the speed of the engine. The said regulator or governor
being independent may receive its rotary motion either from the driving
band of the engine or otherwise. The same result may be obtained by
the aid of a governor based upon the principle of the aspiration of air
through an orifice, the size of which is regulated according to the speed
to be obtained. The governor or regulator (Figure 5) consists of a
cylinder attached to the rod of an eccentric, also of a piston, the rod of
which is connected to a spring plate, which compresses more or less the
india-rubber gas supply tube.
When the entire apparatus descends by the movement of the eccentric
the rod of the piston acts upon the blade spring and replaces it in its
original position.
By these various improvements a simple and economical prime mover
is obtained, which is casily placed, and is applicable in cases where

page_text: Having now described and particularly ascertained the nature of the
said Invention, and the manner in which the same is or may be used
or carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,―
First. The peculiar system or mode of utilizing the explosive force
derived from mixtures of air and gas, or of other explosive mixtures
employed in gas and similar motive-power engines by increasing the
length of stroke of the piston and reducing its surface in the same
proportions with a view to increasing the rapidity of action of the
explosion upon the piston, as herein-before described.
Secondly. The preliminary heating of the walls of the cylinders of
gas and other similar motive-power engines before starting them,
substantially in the manner and for the purposes herein-before described.
Thirdly. The application of large radiating surfaces to the cylinders
of gas and other similar motive-power engines, for the purpose of
maintaining a uniform moderate temperature in the same, as herein-
before described.
Fourthly. The application and use of the arrangement of return
connecting rod to and in the transmission motion of gas and other
similar motive-power engines, as and for the purpose herein-before
described and illustrated by the Drawings.
Fifthly. The distribution of air and of gas in gas motive-power
engines by the use of a single equilibrium slide valve in combination
with the peculiar arrangements for bringing the air and the gas to the
said valve, as herein-before described and illustrated by the Drawings.
Sixthly. The peculiar construction and arrangement of air and of
gas valves for gas motive-power engines, as herein-before described and
illustrated by the Drawings.
Seventhly. The peculiar combination and arrangement of driving gear
and appliances in connection therewith for driving or actuating from the
said improved motive-power engine one or more intermittently working

page_text: machines, such, for example, as sewing machines, as herein-before
described and illustrated by the Drawings annexed.
In witness whereof, I, the said Edwin Powley Alexander, have
hereunto set my hand and seal, this Fourteenth day of June,
in the year of our Lord One thousand eight hundred and seventy- 5
six.