IMPROVEMENTS IN AND RELATING TO ENGINES OR APPARATUS FOR COM- PRESSING AIR OR OTHER FLUIDS, WHICH IMPROVEMENTS ARE PARTLY APPLICABLE TO OTHER ENGINES
Year: 1881

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for an Invention of
"IMPROVEMENTS IN AND RELATING TO ENGINES OR APPARATUS FOR COM-
PRESSING AIR OR OTHER FLUIDS, WHICH IMPROVEMENTS ARE PARTLY
APPLICABLE TO OTHER ENGINES." A communication from abroad by
Ebenezer Hill, of South Norwalk, Connecticut, United States of America.
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 24th June 1881.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN AND RELATING TO ENGINES
OR APPARATUS FOR COMPRESSING AIR OR OTHER FLUIDS, WHICH IMPROVEMENTS
ARE PARTLY APPLICABLE TO OTHER ENGINES." A communication from abroad
by Ebenezer Hill, of South Norwalk, Connecticut, United States of America.
This Invention relates to improvements in air or gas compressing engines, in
which what is termed serial compression is accomplished by the use of two or more
compression pumps, by which the air or gas is compressed in the first pump and
then is conducted to the second pump, and again further compressed, and so on in
the series until the required degree of pressure is produced. The first part of the
said Invention pertains to certain improvements in the inlet valves for air com-
pressors, in which disc or puppet valves are used for inlet valves to the inlet
cylinder, and comprises the formation of a recess in the inner face of the head of
the cylinder of sufficient size and depth to receive the valve at its greatest
"throw
or "lift," and the placing of a guard plate or shield over the said space,
the inner face of which plate may be flush with the inner face of the head, so that
the valve may not be drawn into the cylinder if its stem should be broken or it
becomes detached from any other cause, as will hereinafter appear.
This part of my Invention is illustrated in Figures 1 and 2 of the accompanying
Drawing, in which,―
Figure 1 is a section of a portion of a cylinder head and of the valve seat and
guide, the valve being shewn in elevation.

page_text: Figure 2 is a plan of the inner face of the guard or shield, and a portion of the
cylinder-head.
In these Figures A represents a portion of the cylinder head of an air or gas
compressor, and B is the valve of the ordinary disc form; this valve is supported
by its stem C in a tube D, which is supported by wings E, cast upon the seat F,
screwed into the head of the cylinder; G represents a spring to close the valve, and
Ha check nut.
At K in the head of the cylinder is a recess or chamber of sufficient size and
depth to permit the entire disc of the valve to enter when fully open, and yet be
within the inner face of the head, and over the said chamber is fastened a shield or
guard as at L; this shield may be let into the face of the cylinder, so that its
inner face and the face of the shield may be flush with each other, as shewn in
Figure 1, and so that the piston may work up close to the head if desired.
Upon the inner face of the valve is formed a stem N which extends into a
hole N in the shield, and serves as a support to the valve in case it is broken from
its stem from any cause whatever, and thus the valve might work for a time by its
bearing in the shield or guard. As an additional means of safety guides may be
formed on the guard, as at O, to extend, say, from three points into the recess in
the head, and so that their edges may receive the disc of the valve, and thereby
serve to guide it to and from its seat in case it were broken from its stem.
It is evident that the form of these guards may be different to that shewn in
the Drawing, and instead of a single piece of metal for each valve, a plate may be
.used for all the valves in the head. So also with reference to the stem that works
in the guard or shield, it may be made very large, and thereby diminish the dead
air space formed by the recesses in the head.
Instead of a shield or guard to protect the valve, as shewn, there may be lugs or
guards fastened upon the back of the valve, as at P, which lugs or guards extend
outwardly through the valve seat, and have their exterior end bent outwards to
overlap the seat, so that if the valve should become loose in any manner or broken
from the stem, the said projecting end would save it from dropping into the
cylinder. I prefer however to employ the first arrangement herein described, as it
is altogether the most secure and workmanlike.
The second part of this Invention pertains to that class of apparatus that are
technically termed ". jacketted cylinders," or that have spaces between the interior
and exterior faces of the cylinders for the circulation of water, or the various cases
that may be required to be either cooled or heated, and this part of the said
Invention comprises the formation of the cylinder proper with the required cavities
or spaces on its interior surface for the desired circulation, but with ribs or studs
in the said cavities to serve as bearings for the inner lining of the jacket; then
boring out the said cylinder or the inner faces of the said ribs or studs to the
required diameter, or as much less than the thickness of the lining, and then
forming a lining of thin sheet metal of nearly the required diameter of the said
bore, so that it may be easily forced into the cylinder, and then rolling the said
lining into close contact with the said ribs or supports, as hereinafter described.
This part of my Invention is illustrated in Figures 3 and 4 of the Drawing, in
which,―
Figure 3 represents a longitudinal section of a cylinder without its heads, and
Figure 4 is a partial cross section of the same.
In these Figures A represents a portion of a cylinder which may be used either
for water, air, or various gases, and in this case there is provided an exterior
cylinder, as at B, upon which may be cast, all the seats and bosses for connection
and the like, so that the interior cylinder may be removed, and rebored and relined
without disturbing the connections otherwise than by removing the heads.
Upon the inner face of the cylinder A. are formed ribs C extending the entire
length of the jacketted chamber; these ribs have spaces between them to give the
required circulation or to form the jacket chamber, or in place of the said ribs,
studs or projections, as alternated pieces of ribs, may be cast upon the interior of

page_text: the said cylinder, as at D; or they may be arranged spirally in sections, as at E,
Figure 1, or other convenient supports for the lining which is shewn at F may
be employed.
After the said cylinder A is cast with either or any of the said projections, it is
bored out, that is to say, the inner faces of these ribs or studs are dressed or bored
to a certain diameter, and a lining, as at F, of thin sheet metal, such as copper,
brass, or the like, is formed of nearly the interior diameter and then brazed at its
edges; it is then shoved or forced into the said cylinder, and a boring bar with a
roller of considerable surface is introduced into the interior, and the said lining is
thereby rolled or forced outwards until it bears upon the said ribs or studs, and
thereby forms a fixed lining for the cylinder, and also an inner wall or facing for
the jacket.
If the spaces between the ribs or studs are required to be of such considerable
size that the lining under the rolling action will be forced into thein, they may be
filled with some alloy, such as spelter, and bored out at the same time the ribs or
studs are faced, and after the lining has been rolled in place, the said filling may be
melted out and thus the lining may be left smooth for the piston.
If however it is desirable to have a very thin lining for the transmission of either
heat or cold, the ribs and spaces may be made very small and extend longitudinally
through the cylinder, and then the lining may be rolled in with a small rolling
surface, thereby forming small grooves between the ribs, and thus making the inner
surface of the cylinder slightly fluted or corrugated, in which case a soft packing
for the piston may be used, or metal packing rings may be fitted to it.
It is evident that some substance other than spelter may be used to fill the said
grooves or spaces, and that a plastic substance may be used, and then dissolved or,
driven out, instead of being melted when they are required to be filled.
It is also evident that the exterior cylinder B may be dispensed with, and the
attachments may all be made upon the single cylinder A, to which the tubes for the
inlet and exit of the substance passing through the jacketted spaces may be attached
as shewn at X and Y.
The third part of this Invention pertains to certain improvements in compound
air compressors, in which two or more compressing cylinders are used, and are
driven by a steam engine. This part of the said Invention comprises the combi-
nation of two or more air or gas coinpression pumps with a steam engine and a fly-
wheel shaft, in such a manner that the piston rod of the steam engine will be in
line with the piston rod of the compression pumps, and either below or above the
fly wheel shaft, and the said shaft will be in line with the centre of the cross head
wrists that drive the said fly wheel shaft, as hereinafter described. It also comprises
the combination with an air compression engine having two or more compression
pumps or cylinders, of a slide valve or its equivalent as an inlet valve to the first
cylinder, and operated by positive mechanism from the main shaft of the engine, as
hereinafter described. It also comprises the combination of a cooling or water
circulating apparatus, with two or more compressing cylinders or pumps, in such a
manner, that the water or cooling agent begins to circulate around the first com-
pression cylinder, thence through conduits leading to the second cylinder, and thence
around the second cylinder or pump, and so on from the prior to the secondary
pump in the entire system, as hereinafter described.
This part of my Invention is illustrated in Figures 5, 6, and 7 of the Drawing, in
which,-
Figure 5 is an elevation partly in section of an air or gas compression engine,
having two.compression cylinders, and a steam engine with piston rods in line with
each other, and a circulating apparatus for the cooling agent between the com-
pression cylinders.
Figure 6 is a section of the slides with the cross head partly in elevation and
partly in section.
Figure 7 is a plan or top view of the said cross-head.
Referring to these Figures, A represents the bed or frame of the machine upou
.

page_text: which is mounted the steam engine B, and two compressor pumps C and D, the
pump C being the first or inlet pump for the first compression. E represents the
fly wheel shaft located between the steam engine and one of the compressors, so
that the entire mechanism may be combined in a small and compact form upon the
same bed or frame.
The cylinder of the engine and the compressors are all so located that their
piston rods are in line, as represented at F, F, F2, and in the example shewn these
rods are located below the fly wheel shaft, but they may be arranged above the
said shaft if desired. The piston rod of the second compressor is strictly speaking
an extension of the rod of the engine, as shewn in Figure 5, and extends through
the cylinder, and is connected to a horn G or a depending projection from the cross
head which is shewn at H, and which is mounted on slides K in such a position
that its wrists are in line with the fly wheel shaft, and therefore the crank pins L
on the fly wheels will have equal velocities in equal spaces in any portion of their
revolution.
In such an arrangement of the parts, the power of this engine is direct acting to
the pumps instead of through cranks, as usual, and the cross head is only required
to regulate the speed by first imparting motion to the fly wheel or wheels, as the
case may be, and in turn from them to the piston rods.
The horn G which connects the piston rod to the cross-head is made cone shaped,
as shewn at G¹, and fits into a corresponding box G2 which is fitted into the cross
head; these parts are held in position by a cap and screw bolt, as shewn at G³ and G*,
so that the said horn may be rotated in the said box if desired. Upon the lower
end of the horn G is a horizontal sleeve Go that receives the ends of the piston
rods F¹ and F2, which have conical ends as shewn, fastened in the sleeve by keys
in the ordinary manner. By such an arrangement it is evident that if from any
cause the connecting rods on one side should be a little longer or shorter than on
the other side, there would be no cramping of the parts, as the cross head could
vibrate on the conical shaped horn G, and it also serves as an easy means of
adjustment.
Concerning the second portion of this head or division of my Invention per-
taining to the use of a slide valve in combination with compound air compressors,
it may be here remarked that the inlet valve shewn at M is of the form known as
the grid-iron slide valve, and is operated by an excentric M¹ on the main shaft
through a lever M2 and a connecting rod M³ which engages with the valve by logs
which extend through the cover of the valve chest, and thereby causes regular
reciprocation according to the revolution of the main shaft. I do not however
limit myself to slide valves and excentrics, but may use any of the positively
operated valves common to engines and pumps as ordinarily constructed, without
departing from my Invention. The qualities however desired in a slide air inlet
valve are, large port area, and a proper time for opening. But in making a large
port area, a large clearance-space is unavoidable, and the said space is objectionable
from the fact that air at each stroke of the piston is compressed but not discharged,
and hence a loss of efficiency in the machine accrues. If however the inlet valve be
kept closed after the piston recedes on its return stroke, then the air which has
been left behind in a compressed state will expand until it reaches atmospheric
pressure, and while so expanding will return its pressure upon the piston. When
the air so expanded has reached atmospheric pressure, then is the proper time for
opening the inlet valve, but if opened before, then some pressure would be lost, and
if not opened until afterwards, then a partial vacuum is formed behind the piston.
Now if it were possible to preserve a constant pressure against which the piston is
working, then a valve could be easily constructed, and set to work properly under
such conditions. But if there is any change in the said pressure, as, for example,
where a single cylinder is working into a reservoir from which varying pressures
are required, then it is evident a corresponding change must be made in the time of
opening the inlet valve.
Such a capacity or adaptation of the parts however would require very com-

page_text: plicated mechanism, and therefore to determine the exact time at which the said
valve may be opened and closed a second compression pump is employed of smaller
diameter than the first, and into which the air from the inlet cylinder is forced. This
second cylinder encounters the varying pressures in the air reservoir, and is provided
with automatic poppet valves, and hence the first pump only forces air into the
second and smaller pump, and the pressure in the first pump never rises beyond a
known point predetermined by the relative proportions of the two cylinders. These
proportions are determined when the engines are constructed. This however could
not be effected if a second cylinder were not used.
Again the pressure in the inlet pump or cylinder is much less than the pressure
in the reservoir, and hence the friction of the slide valve is much lighter than it
would be were the larger cylinder to discharge directly into the reservoir or
without any compound cylinders or pumps, and therefore by such a combination all
the heretofore troublesome objections to the use of slide valves in air compressors
are overcome without loss of power or costly attachments, and all the advantages of
the serial and compounding pressures are at the same time secured.
The third part of this branch or division of the said Invention relates to the
cooling devices, in which thin linings are used for the compression pumps as above
described. One of the said linings is shewn at N in the large or inlet compression
cylinder, and forms a water chamber O, into which water is admitted through a
pipe P, and after circulating around the said thin lining in the first cylinder passes
out through a pipe R to a cooling apparatus S, which is intermediate between the
compressors C and D. This cooling apparatus may be of any desired form, but as
shewn in the Drawing is cylindrical, and contains thin tubes T, through which the
air from the first pump passes to the second; water circulates around these tubes in
the outer case S.
Deflecting plates W may also be introduced to more thoroughly circulate the
water from side to side in the outer casing, and then the water is conducted by a
pipe R' to the water chamber in the second cylinder, where a thin lining is used as
in the first cylinder, and around this the water circulates and finally passes off
through an outlet pipe as at X. As above described the water begins its circulation
in the first cylinder, then on through the cooling apparatus, and then through the
second cylinder. This direction of the passage of the water is very important, as
the coldest water comes in contact with the inlet air-cylinder where the first part
of the total compression is effected, and it is known to engineers that the increment
of heat from compression is greatest during its early stages, and hence.it is desirable
to have the cooling process most efficient at that time. As the air during com-
pression passes through the machine the water follows it, and by reason of the
successive compressions the temperature of the air is continually above that of the
water, and the water continues to receive heat until finally discharged, and thus a
given amount of water becomes hotter and carries away more heat by circulating
in the direction of the compression than in any other manner.
It is evident that in carrying into practice this part of my Invention the cylinders
may be arranged in a different position to that shewn, and that the air cylinders
may be attached to different engines; also that more than two compressors may be
used if desired.
The fourth part of the said Invention pertains to that class of air compressors in
which serial compression is accomplished by means of two or more compression
pumps in combination with a steam or other similar engine, and where a high degree
of compression is required, and this part of my Invention consists chiefly in
combining an automatic governing apparatus between two compression pumps of
different capacities, so that air or gas under pressure from the larger pump may be
conducted to the smaller pump and again compressed to any predetermined degree
at which the regulator may be set, and the said pressure maintained at the said fixed
degree automatically as hereinafter described.
It may be here remarked that in carrying into practice this part of the said
Invention the arrangement or construction of devices as shewn need not be followed,

page_text: as many other methods will be suggested to competent engineers for operating the
supplemental pump or the governing or regulating devices, but a great necessity
exists, as in mines and in the construction of tunnels and the like, and for hoisting
purposes where air is used as the agent for operating the drills, hoisting engines,
and the like, that a much greater degree of air pressure be furnished than is
required for the ordinary work in such places. For this purpose I so combine a
supplemental air compressing pump with the other compressors or their reservoirs,
whether one or more, in such a manner that whenever this extra force is required
it will be supplied by the said pump, and its supply will be furnished automatically
by the governing devices. One form of such an apparatus is shewn in Figures S,
9, and 10 of the Drawing, in which,-
Figure 8 is a plan of two air or gas compression pumps or cylinders combined to
co-operate or work together.
Figure 9 is a longitudinal section through the smaller pump.
In
Figure 10 is a transverse section through both of the pumps shewn in Figure 8.
Referring to these Figures, A represents one of the pumps for compressing the air
for ordinary pressures or as used in serial compression, and B is the supplemental
pump in this case arranged by the side of the other pump; the piston rod C of this
pump B is attached to a projection from the cross head from the other pump, as
shewn at D, and a connecting pipe E leads from the first to the second pump.
this pipe E there is provided a valve F, which when closed prevents the passage of
the air from the larger pump to the smaller pump, and the said valve F is attached
by a stem to a lever G mounted upon the exterior of the valve chamber, as shewn ;
this lever is weighted by a ball, as at H, which ball may be moved to and fro as
on an ordinary safety valve lever to keep the said valve open or raised from its
seat.
K is a piston attached to the said lever G, which piston works in a short
cylinder L mounted upon the connecting pipe E or in other suitable or
convenient position. The lower end of this cylinder L is connected with the
discharge side of the supplemental compressor by a pipe m, so that whatever
pressure exists in the pipes or reservoirs on the discharge side of the supplemental
compressor B, will be exerted against the piston K and tend to raise the weighted
lever and thereby close the valve F, and whenever the pressure is sufficient to close
the said valve then the supply of compressed air from the other pump is cut off,
and the piston of the supplemental pump will work in vacuo, or nearly so.
When, however, a draught is made upon the reservoir attached to the
supplemental pump, then the pressure against the piston K will fall and the valve F
will be opened, and another supply of the already compressed air from the other
pump or reservoir will be furnished to the supplemental compressor until its
reservoir is again charged to the predetermined or acquired pressure, and thus
extra supplies of air pressure for special purposes will be furnished automatically.
It is evident that the supplemental pump or compressor may be operated by an
independent engine, in which case some well known governing attachment for
controlling its motion would have to be provided to keep the engine under control
according to the work required.
Having thus fully described the said Invention, as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,
First. In an air compressing engine having disc shaped inlet valves, a recess in
the head for each valve, and a shield or guard over the said recess, substantially as
above set forth and for the purpose specified.
Second. An inlet valve for an air or gas compression engine provided with hooks,
as at P, extending from its back and through its seat to serve as guards, as above
set forth and for the purpose specified.
Third. A jacketted cylinder (either for water, steam, air, or other gases) formed
with ribs or studs in the jacketted space or spaces and faced by boring, or otherwise,

page_text: and then covered with a thin sheet metal lining rolled into the proper position, as
above set forth.
Fourth. The method of lining jacketted cylinders, consisting in forming bearing
ribs or studs in the jacketted spaces, then filling the intervening grooves or spaces
with an alloy or other hard substance, then boring out the cylinders, and lastly
rolling in a thin sheet metal lining, as above set forth.
Fifth. In an air compressing apparatus the combination of two or more pumps
or compressors with a steam engine and a fly wheel shaft in such a manner that the
piston rod of the engine will be in line with the piston rods of the compressors
while the cross head is in line with the fly wheel shaft or axis, as above set
forth.
Sixth. The combination with the cross head of the horn G and its sleeve for
connecting the piston rods of air compressing pumps, as above set forth.
Seventh. The combination of a positively operated air inlet valve with
compound cylinders in which serial compression is produced, whereby the working
pressure of the inlet cylinder is rendered practically uniform by the proportionate
sizes of the several cylinders, as above set forth.
Eighth. In a compound air compressor the combination of water spaces in the
cylinder and intermediate cooling apparatus with suitable inlet and outlet pipes,
whereby the water will be caused to circulate in the direction of the air during the
compression, as above set forth.
Ninth. In air or gas compressors in which serial compression is accomplished by
two or more compression pumps, the combination of a supplemental pump for
special compression with suitable governing devices for controlling its supply of
compressed air, as above set forth.
Tenth. The combination with an air or gas compression pump or its reservoir of
a supplemental pump or compressor for special pressures and a valve connected to
a weighted lever provided with a piston working in a cylinder which has a
connection with the discharge side of the said supplemental pump, substantially as
and for the purpose above set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twenty fourth day of June, in the year of our Lord
One thousand eight hundred and eighty one.
WA. ROBT. LAKE. (L.S.)