IMPROVEMENTS IN AND RELATING TO APPARATUS FOR UTILIZING COMPRESSED AIR AS A MOTOR
Year: 1884

page_text: COMPLETE SPECIFICATION,
J, WILLIAM ROBERT LAKE, of the firm of Haseltine, Lake, and C° Patent
Agents, Southampton Buildings, in the County of Middlesex, do hereby declare
the nature of my invention for "IMPROVEMENTS IN AND RELATING TO APPARATUS
FOR UTILIZING COMPRESSED AIR AS A MOTOR" and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement :-
This invention relates to apparatus to be driven by compressed air.
Up to the present time steain has been the principal motive power employed in
locomotives, vessels, or stationary engines.
Experiments have, it is truo, been made for the application of air as a motive
power, for tramways force-pumps, and compressed air brakes, but in these various
uses the compression of the air is invariably effected by an external power which is
independent of the engine which uses the compressed air.
This cugine, in a word, does not supply itself with its own motivo power and is
in the same condition as tho steam locomotive before the invention of the tubular
boiler by Stephenson and by Seguin. It is impossible to undertake as long
journeys with compressed air engines as with steam engines by reason of the
inevitable necessity which arises of renewing at short intervals the supply of
compressed air.
To discover the means of supplying the machine with its motive power through
the medium of an agent which costs nothing, as air, and to accomplish this in such
a manner that the machine itself compresses the air designed for its feed, is the
problem to be solved.
In order to attain this end completely, two things are requisite, first to forco
into a closed vessel under considerable pressure, the greatest quantity of air in the
least possible time; and second, to effect this compression so as to use only a
portion of the work of the engine and to reserve the greater portion for the useful
effect.
The object of this invention is to fulfil these requirements.
I must here remark that this motor is applicable to locomotives, vessels,

page_text: I describe here only the adaptation of the apparatus to a locomotivo. In the
other adaptations the principle is the same, the mode of application only differing.
I replace the steam by a permanent gas which is air.
The air becomes a power of the first order from the moment it is compressed.
It is therefore by compressed air that I succeed in constituting the most t
powerful motor hitherto known and in replacing steam in its applications.
Also, everything relating to the production of the steam is dispensed with in
the improved engine. Of the actual locomotive only the cylinders, and the
appliances for the distribution of the steam are retained, because the compressed
air acts in the same manner as the steam.
Having thus set forth the principle of the invention, I shall describo the manner
in which I put the same into practice, referring to the accompanying drawing
which represents a sectional elevation of a locomotive provided with the
improvements.
1
The air is compressed by means of a screw having two threads A A' acting like 1
the vanes of a fan, and which, by reason of its construction, conveys the column of
air into the compressing cylinder B. The truncated cone which contains the
thread A' of the screw cominences to compress tho air.
The shaft d, of the screw rests upon two supports b, b¹.
The screw is of such size that it is capable of projecting into the cylinder the
volume of air necessary for feeding the engine.
For this purpose I give it an average velocity of a hundred revolutions per
second.
The air forced into the compressing cylinder B can escape only through a
valve C, fixed at its upper portion, into the reservoir L L L As the air is
compressed to say twenty atmospheres within this reservoir, this valve supports
upon its upper surface a pressure of twenty kilogrammes per square centimetre
that is to say, the said air only escapes through tho said valve after having been
compressed to a little above twenty atmospheres, which pressure it ought to attain.
It is to be noticed that the size of the compressing cylinder, by a special:
arrangement for the purpose, occupies only the twentieth, plus a fraction, of the
space occupied by the screw. At evory revolution of the screw, the air is therefore
compressed and having acquired a power of 20 kilogrammes plus a fraction, lifts the
valve and feeds the reservoir.
This arrangement has for its object to diminish considerably the expenditure of
power necessary for the compression of the air which imparts motion to the whole
system.
The air reservoir occupies entirely the place of the former boiler, and its form
and dimensions are retained. It is charged once at first with air at say twenty
atmospheres, as I have chosen this example above. It is fed subsequently by the 4
screw and the compressing cylinder. From the reservoir the compressed air
leaves by the same passages as those by which the steam left, and passes to the
slide valve chests and thence to the cylinders H H acting upon the pistons I I.
The motor for the screw is the crank-axle which in turn receives its movement
from the pistons 1 I through their rods g, g.
For this purpose, and for causing at will the forward or backward motion, two
worm-wheels hh' are mounted upon the crank-axle, one on the right-hand side
and the other on the left-hand side of the middle of the axle. The worm-whecla
actuate two worms E E¹ having each its separate shaft f, f¹ respectively. At their
ends these shafts f, f¹ carry spur wheels M M which engage with an intermediato
wheel M¹ carried by a horizontal shaft e at right angles to the crank-axle. This
latter shaft receives the motion sometimes from the wheel on the right-hand sido
and sometimes from that on the left-hand, according to the direction of movement.
One of the wheels or h¹ always turns loosely upon the crank-shaft according to
which wheel is driven by the sliding clutch N.
The shaft carries at one extremity a large spur-wheel F¡which drives the
wheel a fixed upon the same shaft as the scrow,

page_text: In consequence of this arrangement the engine can cause the forward and
back ward movement at will and the screw receives a constant rotary motion in
one direction, a necessary condition considering that the action of the screw is to
drive the air always in and never to eject it.
With the exception, as I have said, of the parts designed for the production of
the steam, which are no longer required, all the parts of the locomotive or other
engines remain as they are at present. I increase certainly the diameter of the
cylinders in the locomotive, but I give them a little less length, in order to avoid
the augmentation of the space in a cylinder.
The object is to increase the power of the locomotivo considerably without
affecting the general arrangements of the engine.
From this the principal feature of the system becomes obvious.
In order to obtain an engine which feeds itself and produces important useful
work, it is requisite on the one hand to furnish a considorable and constant power
so as to provide the requisite power for feeding the engine and for producing the
effective work; and on the other hand it is necessary to diminish as much as
possible the power required for the compression of the air, in order to leave the
greatest part of the power for the work of the engine.
This system fulfils this object; for, I have reduced to the rotation of the screw
and to the compression of a cylinder of air, or in other terms, to the compression
of a volume by the screw, the necessary power for overcoming the resistance.
The remainder belongs to the effective power, that is to say, to the power which
the pistons receivo. Now, by reason of the arrangements of this ongine, the
effective power is constant and integral whilst the resistance is partial. This
latter is multiplied, it is true, but it constitutes at the same time only a portion of
the real power of the engine. This engine, therefore, after having provided for the
resistance, retains the principal portion of the power for its useful work.
In the application I have, in fact, the pistons which transmit a constant power,
without interruption, of one hundred per cent, whilst the opposing forces, (scrow
and compressing cylinder,) require only twenty-five per cent, in a rapid manner, it
is true, but gradually. The useful work will therefore always have the benefit of
seventy five per cent.
It is due to this system that I have been enabled to solve the problem which
consists in providing an engine which feeds itself, not receiving any power from
outside and reserving for its useful work the principal portion of its power.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that I claim
as the distinctive feature of the new system of atmospheric motor for locomotives,
vessels, stationary engines etc, the combination of a scrow, receiving motion from
the principal shaft of the motor and feeding a reservoir with compressed air
according to the conditions described in this specification and represented in the
annexed drawing.
HASELTINE, LAKE & Co.
For the Applicant,