Improvements in Air Engines or Motors.
Year: 1890

page_text: Date of Application, 18th Feb., 1890-Accepted, 22nd Mar., 1890
COMPLETE SPECIFICATION.
[Communicated from abroad by ALBERT SCHMID and JOHN CHARLES BECKFELD, both
of Allegheny, Pennsylvania, United States of America, Mechanical Engineer.]
Improvements in Air Engines or Motors.
I, HENRY HARRIS LAKE of 45 Southampton Buildings, Chancery Lane, London,
in the County of Middlesex, Patent Agent, do hereby declare the nature of this
invention 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 engines or motors operated by compressed air, the main
object of said invention being to provide a better and more practicable means of
counteracting or lessening the objectionable effects produced in such motors by the
intense cold developed by the expansion of the air.
The plan for accomplishing this, which constitutes the present invention is to com-
press, by means of the motor itself, or by the energy of the compressed air by which
it is operated, a given volume of air and to utilize the heat developed by such com-
pression to counteract the cold either by raising the temperature of those parts of the
motor most exposed to the refrigerating effects of the expanded air or to impart
warmth to the compressed air on its way into the motor or both.
This invention also provides for the utilization of the air thus compressed in driving
the motor, and in other respects, hereafter set forth, the construction and operation of
the motor are improved.
In carrying out this invention there may be employed any suitable form of com-
pressed air engine, but the application of the principle of the invention is herein
illustrated by a form of compound engine to which the description will be confined.
In conjunction with said engine or forming a part thereof, there is used a compression
cylinder and piston of relatively small capacity, in which by the operation of the
engine and preferably at each stroke, the air is compressed and forced through a
suitable valve or valves, through passages which conduct it around, or in close
proximity to the exhaust ports, valves or other parts most exposed to the cold, and
then into the main pipe which supplies the motor with the compressed air which
drives it.
For the sake of greater economy of mechanical construction and for avoiding loss
of mechanical energy, the driving cylinder, or the expansion cylinder in the present
is constructed with two compartments, one for the development of power by the
expansion of the compressed air, the other for the compression by the piston on its
forward or down stroke, of the air to be subsequently utilized as above set forth.
case,
Provision is also made for the introduction into said latter compartment and along
with air drawn into the same by the return of the piston of a spray of water or other
fluid by the use of two valves, one closing on the down stroke to prevent the escape
of the air, the other opening when the pressure in the compression chamber becomes
sufficiently high to admit the compressed and heated air to the valves and the main
supply pipe, as above set forth.
Thus there is used a supply of compressed air for operating a motor and for
counteracting the refrigerating effects, of its own expansion which heretofore have
been found so objectionable in motors of this character. The invention comprehends
this broadly.
To illustrate the practical construction and working of the invention, reference is
made to the drawings annexed and in which is shown, as above stated, the particular
form of motor which is preferred.
Figure 1 is a vertical central section of a complete motor embodying the
improvement

page_text: The main portions of the motor being of any well known character, require a less
detailed description than the particular features of novelty which distinguish the
invention, and such parts may be greatly varied. These consist of a high pressure
cylinder A with a piston B working therein, and a low pressure or expansion
cylinder C containing a piston D.
The pistons connect by piston rods with cranks A' on the main shaft B¹ on which is
fixed the fly wheel G¹¹.
The valve mechanism which controls the admission of the compressed air from the
main pipe E into the high pressure cylinder A, the expansion of the air therefrom
into the low-pressure cylinder C, and the final exhaust of the expanded air, is located
above the cylinders and is controlled by a bell-crank lever or rock-shaft D¹ operated
by an eccentric E¹ on the main shaft B¹.
.
The valve mechanism is shown as composed of a cylindrical valve F arranged to
slide in a bushing F in an outer valve casing G containing passages or chambers
with ports in or through said bushing, the character and location of which will be
understood from the subsequent description of the operation of the motor.
Below the cylinders is a chamber G₁ for containing water and oil which is splashed
up by the piston rods and cranks against the under sides of the pistons and the walls
of the cylinders.
The larger or expansion piston D is made up of two parts of unequal diameter.
The wider portion, or head, fits the walls of the cylinder proper, while the reduced
portion or body H works air tight in the part I forming the open end of the cylinder (),
and having a smaller diameter than the main portion.
Thus two working compartments are formed on opposite sides of the piston, the
lower of which, for convenience may be designated the cylinder J.
Communication from the outside to the cylinder J is secured through a passage K
containing a valve b. Below the valve is a receptacle c, containing water the level
of which is maintained constant by a supply pipe d and overflow pipe e.
A small tube f from the main E is bent down over the water in receptacle c and
opens immediately below the valve b. A short tube g extends from the interior of
the pipe into the water, thus forming a spray or atomizer by means of which when
the valve is open and air is being drawn into the cylinder J, a spray of water is
thrown into the passage K and the cylinder.
A passage is also formed from the cylinder J through a valve L and pipe M to a
jacket or chamber N surrounding more or less the exhaust port P and the main
valve F. A pipe O connects this chamber with the main E.
The operation of this device is as follows:-The compressed air from the main E
being admitted to the motor it passes through ports h and i, assuming the valve F to
be in position to permit this, into the cylinder A. This drives down the piston B
until, by the movement of valve F, the air supply is cut off. Communication between
cylinders A and C is then established through the valve F and ports i and n.
The compressed air then expanding, forces down the piston D until by the valve F
the exhaust through ports n and o are opened, when the cycle of operations above
described is repeated.
In its downward movement the piston D compresses the air in cylinder J and raises
its temperature. As soon as the pressure equals that in the main E the valve L is
raised and the heated air passes up through the pipe M and chamber N where it
imparts a portion of its heat to the surrounding walls and then enters the main E
to pass through the engine cylinders together with the main supply.
Each time the piston D rises a fresh supply of air is drawn into the cylinder J, and
together with the air, the spray of water. This latter on the descent of the piston D
is converted into steam. The advantages and useful effects of this are numerous.
The expansion of the vapour is utilized in the subsequent working of the motor; the
steam absorbs and retains much of the heat that would otherwise be lost by radiation
and conduction and serves the better to raise the temperature of the parts with which
it subsequently comes in contact, and furthermore, on reaching the cylinder G with
the compressed air after passing through the high pressure cylinder A, considerable

page_text: heat including that which is latent is withdrawn therefrom by the sudden expansion
of the air which assists materially in maintaining the desired temperature and
preventing too great a degree of cold.
It will of course be understood that due consideration must be had to the proper
relative capacities of the two cylinders and J to render the plan herein described
practicable and useful. With an engine or motor constructed substantially as shown
in the drawings, very good results may be obtained, the loss of power in the
compression of the air in cylinder J being, under the circumstances, comparatively
slight and due mainly to friction.
The invention is not limited to the special devices herein shown, nor to the special
manner of combining and operating the motive devices and the means for compressing
the air to impart warmth to such devices.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what
I claim is
1. The method of preventing the effects due to expansion of the air in compressed
air engines which consists in compressing air in a suitable device by the compressed
air supplied to the engine and conducting the air thus compressed around or in
proximity to such parts of the engine as it may be necessary to warm.
2. The method of preventing the effects of cold due to expansion of the air in com-
pressed air engines, herein set forth, which consists in compressing air in a suitable
device by the compressed air supplied to the engine, conducting the air thus com-
pressed around or in proximity to such parts of the engine as it may be necessary to
warm, and then uniting such compressed air with the main supply, as described.
3. The combination with an engine or motor operated by compressed air, of an air
compressor operated by the same, and a passage of communication between the
cylinder or chamber of the said compressor and the main pipe by which compressed
air is supplied to the engine, as and for the purpose set forth.
4. The combination with an engine or motor adapted to be operated by air supplied
under pressure thereto, of an air compressor operated by the compressed air supplied
to the engine, and passages for conducting the air compressed thereby around or near
to those parts of the engine which it is necessary to warm, as set forth.
5. The combination with an engine or motor adapted to be operated by air supplied
under pressure thereto, of an air compressor operated by the compressed air, supplied
to the engine, and a passage conducting the air from said compressor to the main
supply pipe, said passage being around or in proximity to those parts of the engine
which it is necessary to warm, as set forth.
6. The combination with a compressed air engine of a compression cylinder or
chamber in which the air is compressed by the operation of the engine, and a valve-
controlled passage for conducting the compressed air around or near to such parts of
the engine as it may be necessary to warm, as set forth.
7. In a compressed air engine, the combination, with a cylinder and piston, of
valve ports at one end controlling the admission and exhaust of the air, a valve-
controlled opening at the other end, and a valve-controlled passage therefrom back
to the main air supply passing around or near such parts of the engine as it may
be necessary to warm.
8. The combination of a compressed air engine, an air compressor operated
thereby, means for introducing a spray into the compressor cylinder, and a passage
from the said cylinder back to the main supply pipe, said passage being around
or near to the parts of the engine to be warmed, as set forth.
9. The combination with a piston of a compressed air engine, of a compression
chamber beneath said piston, a valve-controlled port opening to the atmosphere,
and a valve-controlled passage leading back to the main supply pipe and around
or in proximity to the parts of the engine to be warmed, as set forth.
10. The combination with a compressed air engine of a compression cylinder or

page_text: chamber in which air is compressed by the operation of the engine, a passage of
communication from said cylinder or chamber to the main supply of compressed
air and a device for introducing water into said chamber, as herein set forth.
11. The combination with an air engine or motor, of an air compressor operated
thereby, a device for introducing a spray into the compressor to be converted
into steam by the heat developed by the compression, and a valve-controlled
passage from said compressor back to the main air supply, as set forth.
Dated this 28th day of January 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.