IMPROVEMENTS IN AIR ENGINES
Year: 1872

page_text: LETTERS PATENT to Alfred Vincent Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Mechanical
Draughtsman, for the Invention of "IMPROVEMENTS IN AIR ENGINES."
-A communication from abroad by Charles Philo Leavitt, of the
City and State of New York, United States of America.
Sealed the 4th March 1873, and dated the 19th September 1872.
PROVISIONAL SPECIFICATION left by the said Alfred Vincent Newton
at the Office of the Commissioners of Patents, with his Petition, on
the 19th September 1872.
I, ALFRED VINCENT NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Mechanical Draughtsman, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN AIR
ENGINES," to be as follows:-
This Invention relates to engines in which air being heated serves, by,
the expansion it thus derives, to act as the motive agent. Air is supplied to
the cylinder of the engine by a pump so proportioned and operated that
it supplies the air to the engine at a constant or approximately constant
volume, that is, free from compression, or in other words, at ordinary

page_text: atmospheric pressure, in which state it is heated by the products of
combustion and by the engine, and thereby expanded to give it its activo
pressure within the cylinder of the engine. For producing this result a
fire pot or heater is applied to the base of the engine cylinder to heat the
air delivered by the pump. This pump, which is of like capacity or
thereabouts with the engine cylinder, or acting portion of it, is timed and
constructed or provided with valves, so that only a portion, or approxi-
mately one-half of the air displaced by the pump is passed to the engine
cylinder, the remainder being allowed to escape, and the portion that
enters the engine cylinder is introduced thereto during the half or early
portion of the stroke of the engine piston in its one direction. Either
coal or gas may be used for fuel in the heater, and the air which is intro-
duced for expansion within the cylinder of the engine may be either
simple atmospheric air, or more or less charged with inflammable or other
gases.
When solid fuel is burned an automatic fuel feeder is employed, said
feeder being operated by the engine, and comprising among other
features a discharger, operating at intervals within a semicircular fuel
receptacle to scoop out from the latter a regular determinate quantity
of fuel; also a rocking cup, and a plunger for introducing such dis-
charged quantities to the fire-pot of the engine, when it is burned and
caused to heat the air on its passage to the cylinder.
A hot air engine thus constructed and provided operates without any
increase in the density of the air to be expanded in a simple and efficient
manner, and is free from much or any liability to derangement of parts,
and requires but little personal attention.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Vincent Newton in the Great Seal Patent
Office on the 19th March 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED 30
VINCENT NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Mechanical Draughtsman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Nineteenth day of September, in the year

page_text: of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alfred Vincent Newton, Her special
licence that I, the said Alfred Vincent Newton, my executors, admi-
nistrators, and assigns, or such others as I, the said Alfred Vincent
Newton, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times there.
after 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 Inven-
tion for "IMPROVEMENTS IN AIR ENGINES," being a communication to me
from abroad by Charles Philo Leavitt, of the City and State of New York,
United States of America, upon the condition (amongst others) that I,
the said Alfred Vincent Newton, 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 Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
.Patent.
NOW KNOW YE, that I, the said Alfred Vincent Newton, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, reference being had to the
Drawing hereunto annexed, and to the letters and figures marked
thereon (that is to say) :-
This Invention relates to engines in which air being heated serves by
the expansion it thus derives to act as the motive agent.
The Invention consists in a certain combination with the cylinder of
the engine of a pump for forcing or supplying air to said cylinder when
said pump is so proportioned and operated that it supplies the air to the
engine at a constant or approximately constant volume that is free from
compression, or in other words, at ordinary atmospheric pressure, in
which stato it is heated by the products of combustion and by the engine,
and thereby expanded to give it its active pressure within the cylinder
of the engine.
The Invention also consists in a novel combination and arrangement

page_text: non-conducting material 6 to resist the passage of heat, and the base or
a lower extension of said cylinder similarly lined, and provided with a
fire pot or chamber B in direct communication above, with the bottom
of that portion of the cylinder in which the air is expanded to raise the
piston C, and which may therefore be called the working portion of the
cylinder. The fire pot or chamber B is provided with one or more
openings capable of being tightly scaled for making the fire, and for
cleaning it, also for supplying it with fuel while the engine is in motion,
the latter opening or passage being indicated by the letter D. The
piston C is of greater length or depth than its stroke, and is largely
composed of a non-conducting material to resist passage of heat. Said
piston is hollow, and is connected with the crank E of the main shaft F,
which it serves to revolve by a connecting rod G arranged to vibrato
within the piston. H is a fly wheel on the main shaft F for equalizing
the motion of the engine, or for continuing its motion in the down stroko
of the piston, and I, a pulley by which power may be communicated
from the engine. If desired, two or more engines having their cranks
differently set may be connected with the same main shaft, to render
more uniform its driving effect. J is the cylinder of the pump by which
the air is supplied to the cylinder A. This pump, which may be an
ordinary simple acting one furnished with an induction valve c, and
eduction valve d, has its plunger K operated by a crank L and con-
necting rod M from the main shaft F in a continuous manner, said crank
being of equal throw, or thereabouts, to that of the engine crank E, but
set at right angles to the latter, or thereabouts, and behind or in wake of
it, so that for portions of the engine's stroke in either direction both
pistons C and K move simultaneously in like directions, and during its
remainder portions of the stroke in opposite directions.
The working space of the pump barrel or cylinder J approximates in
capacity the working space of the cylinder A, and by the position of the
cranks E and K as described, the pump in each down stroke of its
plunger discharges half the bulk of its contained air without increasing
the density of the latter, or changing its volume, into the working or
heating portion of the cylinder A, the other portion of the air displaced
by the plunger of the pump in its descent being allowed to escape, either
through an opening in or formed by cutting away the upper portion of
the pump barrel, or through the eduction valve d, and a general exhaust
valve N, or by keeping open mechanically, during the early portion or

page_text: first half of the descent of the plunger K, the induction valve c, which
may be done by connecting said valve with the general exhaust valve N,
or a separate and special valve may be used for thus rendering unavail-
able, as regards supply of air to the engine cylinder, the early portion or
first half of the down stroke of the plunger of the pump, during which 5
period the engine piston makes the concluding portion or half of its
down stroke, driving out through the mechanically worked exhaust
valve N the spent air from the engine cylinder.
The eduction valve d of the pump may have a spring applied to its
back to secure its being closed, except when the opening of it is needed 1
in the working of the engine. This valve controls a passago ƒ which is
bifurcated at ff, to establish communication with the engine cylinder
above and below the fire, and which is fitted with a valve g that compels
the air delivered by the pump to pass through the fire in the chamber B
to the engine cylinder, but allows the spent air from the latter to escape 1
without passing again through the fire.
The exhaust valve N is lifted while the engine piston is going down,
thus allowing the expanded air, after it has donc its duty, to escape, and
is closed while said piston is going up. Said valve is raised mechanically,
and kept raised at or during the period specified by means of a cam O on 2
the engine shaft acting under a toc or lifter attached to the rod of the
.valve.
As the parts are arranged in the Drawing half the air displaced by
the pump plunger, that is, the air displaced while the latter is making
the first half of its descent, passes out through the raised or open exhaust 2
valve N; but when this valve is closed then the remainder of the air
displaced by the plunger of the pump in its descent is thrown into the
engine cylinder during the first half of the up stroke of the engine piston,
without, however, as already specified, increasing the density of the air
that depends for its acting pressure on the engine piston on its expansion 3
by the products of combustion of the engine.
The valve N may close before the engine piston quite completes its
down stroke, thus causing said piston to cushion as it were on the pump,
and producing the same effect as though the pump cylinder were larger
than the engine cylinder, as indeed it may be slightly with some 3
advantage.

page_text: The automatic fuel feeder may be constructed as follows:-P is the
fuel receptacle in which the coal is placed, and R, the discharging device
which is made fast to a rocking shaft h, and shaped so that when rocked
or reciprocated it sweeps within a groove over the bottom and sides of
the fuel receptacle, and during each forward motion takes out from the
latter a certain and uniform quantity of coal, and discharges the same
over the top of the receptacle into a plunger i, down which it drops, or
is swept or cleared by a clearer S, and passes within a hollow cock or
delivering device T, that then is turned to deliver its load into the
passage D in front of a second delivering device or plunger U, which,
moving forward, passes the coal into the fire pot B. The plunger U
then retires, the cock T adjusts itself into a receiving position again, and
the discharging device R and clearer S resume their operations as before,
thus keeping up an automatic supply of fuel to the fire. Motion is
communicated to this automatic fuel feeder by a screw on a shaft k,
which latter is driven by belt pulleys l, m, from the main shaft F at any
desired speed, according to the fuel supply required. The screw on
the shaft k rotates a worm wheel n that is connected by a rod o with an
arm p for rocking or reciprocating the discharging device R, and the
shaft q of the wheel n operates by a cam r conjointly with a spring s to
give to the clearer S its sweeping or reciprocating action. The cock T
rotates with the shaft q to put itself into alternate receiving and
delivering positions. The plunger U is reciprocated by a bent con-
nection w from the rock shaft ħ and link z.
Having now set forth the nature of the Invention of "Improvements
in Air Engines," as communicated to me by my foreign correspondent,
and explained the manner of carrying the same into effect, I wish it
to be understood that under the above in part recited Letters Patent
I claim,-
First. An air engine in which the air is supplied at a constant or
approximately constant volume, and heated or expanded by the products
of combustion used by the engine when said air is supplied by a pump
proportioned in relation to the cylinder of the engine, and combined for
operation with the engine piston, substantially as shewn and described.
Second. The combination with the engine cylinder and its piston of
the fire pot or heater and pump for supplying air to be expanded within
the cylinder, as described, the whole being arranged as specified, or in
any other manner capable of producing a like operation of said parts.

page_text: Third. The automatic fuel feeder constructed and operating sub-
stantially as described.
In witness whereof, I, the said Alfred Vincent Newton, have
hereunto set my hand and seal, tho Nineteenth day of March, in
the year of our Lord One thousand eight hundred and seventy-
three.