IMPROVEMENTS IN MACHINERY OR APPARATUS EMPLOYED IN COMPRESSING AIR OR AERIFORM FLUIDS
Year: 1883

page_text: LETTERS PATENT to Reginald Pelham Bolton of No 1 Victoria Villas
Broxbourne.in the County of Herts Engineer and John William Hartley
of the firm of Hartley and Arnoux Brothers of California Works Stoke-upon-
Trent in the County of Stafford. Engineer. for an Invention of IMPROVEMENTS
PROVISIONAL SPECIFICATION left by the said Reginald Pelham Bolton
and John William Hartley at the Office of the Commissioners of Patents on
the 20th September 1883.
REGINALD PELHAM BOLTON of N° 1 Victoria Villas Broxbourne in the County
of Herts Engineer and JOHN WILLIAM HARTLEY of the firm of Hartley and
Arnoux Brothers of California Works Stoke upon Trent in the County of Stafford
Engineer "IMPROVEMENTS IN MACHINERY OR APPARATUS EMPLOYED IN
COMPRESSING AIR OR AERIFORM FLUIDS
"
Various attempts have been made to overcome the manifold difficulties and
obstacles attendant upon the successful compression of air or aeriform fluid by
apparatus in an economical manner but so far as we are aware such attempts have
not met with more than limited success and the following are some of the
conditions which need to be attained in order to successfully effect Buch
compression
Generally the air or aeriform fluid is compressed under high pressure in a closed
cylinder or box in which a piston reciprocates whilst tightly fitting such cylinder
and that piston is driven to and fro by power such movement of that piston causes
air to be sucked into and discharged from such cylinder through valves which
control such passage as water in a water pump may be.
It is an attendant incident upon air compression that much heat is developed
and this heat is detrimental to the operation of the compressor consequently means
for reducing or removing this heat is an important object-Another prominent
difficulty to be contended with is the tendency of the air to leak past the piston
to the reverse side of the piston in the cylinder where the heated air thus escaping

page_text: mixes with and rarifies the incoming cool air on that side of the piston, such
expansion filling that part of the cylinder with air at a tension which when
compressed by the return stroke represents a loss of compressed air, as against the
same amount of compressed cool air.
It is found in practice that in the suction of air into the cylinder of air
compressing apparatus through valves even of light and unobstructed construction
it is requisite to employ power and generally it is accomplished only at the expense
of a slight vacuum in the cylinder during the instroke and this loss increases with
the increase of speed of the piston.
In order to obviate these difficulties and to effect our improvements we employ
a cylinder body of peculiar construction adapted to permit of the heat developed
by compression of the contained air being better controlled or removed. Also we
so form the cylinder body that the escaping air finds free vent to the atmosphere
at about the middle of that cylinder enabling us to dispense with valves for the
purpose. Also we provide against loss of power by the creation of a vacuum in
the intake of air by enclosing the inlet valves in a suitable case or cover or cases
or covers and we convey air or aeriform fluid thereto under a sufficient pressure to
prevent vacuum arising and which air pressure will suffice to ensure the valves
being opened and the air supplied to the cylinder at all speeds
The compression of the air so supplied we effect by a suitable adjustable injector,
provided with a small jet of high pressure air supplied to it and adapted thereby
to induce a large current of atmospheric air to enter the passage to the inlet valves
of the compression cylinder. Also we provide around either end of the piston and
within the cylinder a self tightening ring or annulus of peculiar construction of
copper or other suitable metal, one edge or part thereof being secured to the piston
whilst the other edge splays against or towards the sides of the cylinder and
under pressure of the air is forced into close contact therewith forming a tight
joint preventing leakage. This ring of metal we cut split or divide to aid its
better operation.
We also provide double beat valves for inlet and outlet of air of light construction
adapted to large area of opening and yet possessing strength to resist sudden
pressure and shocks in operation such as commonly are found detrimental to those
of existing construction
Another form of inlet valve which may be employed according to our invention
has an entirely unobstructed passage way without projecting rib or boss therein
and is also of light and durable construction.
We also cool the air whilst under compression in the cylinder by surrounding
the cylinder body by a chamber containing cold air, such cold being induced by
the expansion of a small quantity of highly compressed air either in a small
working cylinder attached to the rotating or reciprocating parts or in an air
injector of suitable form leading into such chamber. This air cylinder body
consists of a tube with flanged ends and it has around the centre of its length a
corrugation or enlargement forming a channel of any suitable depth. The cylinder
body is contained in a cast iron or other suitable case and is secured by proper
bolts or fastenings to the case. The corrugation or enlargement of the cylinder
permits of its expanding and of the bolts or fastenings drawing the flanges tight
and the cylinder body may be made of rolled sheet brass or other suitable metal of
highly conducting powers for heat without constructing the whole cylinder covers
or sides of such more expensive metal
The cylinder body we construct of such length proportionate to the length of a
solid or other piston traversing therein, such that the one end or edge of the piston
does not travel beyond its own half cylinder or enter the other half but on the
contrary terminates its traverse just short of or just entering the enlargement or
corrugation channel thus obviating loss of power by twice compressing the air in
double stroke in the same part of cylinder as is possible in existing arrangements
moreover by the improved arrangement sufficient interval is given to permit of the
cylinder casing cooling at either end before recommencing compression.

page_text: In some cases we make the piston of length adapted to admit of its edge retiring
beyond the one inner edge of the circumferential channel or corrugation so as to
leave such channel open to communicate with the cylinder and the atmosphere or
to the supply pipe of air as previously described through a pipe or trunk applied
to such channel or corrugation. By these means free air may be admitted to the
cylinder just at the extreme end of the suction or commencement of the
compressing stroke and to facilitate this arrangement in operation we form the
edge of the piston circumferentially rounded or tapered to prevent such edge in its
traverse catching against or injuring the edge of the corrugation or we make the
edge of the corrugation so tapered while the edge of the piston is left square.
In the case of large compressing cylinders we find it convenient to make the
corrugated part or circumferential channel casing divided into separable portions
with flanges one to each portions, for convenience of connection by bolts or other
fastenings or other mode of connecting the separate portions may be employed.
In some cases we admit to the corrugation or channel cold water oil or other
suitable liquid for cooling or lubricating the piston which passes therethrough. In
some cases we make one portion of the cylinder body on one side of the mid
channel or corrugation larger than that on the other side and we fit therein a
piston formed correspondingly of two diameters. The larger diameter of piston
may be adapted to draw air from the atmosphere through a suction chamber or
valves of suitable construction and thence to pass such air through delivery valves
to the suction chamber at the smaller end of the cylinder the smaller piston in
which may draw and compress it to a still higher degree of compression
The corrugation or mid channel to the cylinder enables us to overcome many of
the difficulties ordinarily attendant on the use of cylinders and pistons of two
diameters and facilitates lubrication.
The end of the cylinder casing is divided into two recessed portions in which
inlet and delivery valves are respectively placed and a passage may be arranged to
lead from the suction valves to the side of the cylinder casting and be provided
either with a suitable opening to the atmosphere at either end or a passage from
each recessed portion may be brought to the centre of the length of the cylinler
casting and they may there form one inlet opening. The delivery recesses with
outlet valves thereto may be correspondingly arranged. Over these recesses is
bolted or secured a suitable cover or the recesses may be formed in the cover and
the cover be arranged to drop into the bored end of the cylinder casting and
opening in the side thereof corresponding to those delivery and suction passages.
A second cover over the before mentioned recesses is also provided. We sometimes
allow the inlet recess free communication with the air bolting a small cover over
the delivery valves only in direct connection with an air reservoir or supply by a
suitable pipe or channel.
The bolts employed to secure the cylinder body may be utilised for securing the
outer cover also.
When the cylinder has solid ends or the valve recesses are not made in a
removeable cover we find it convenient to employ two piston rods and these rods
are passed through glands into and through the casing to be secured by screwing
or otherwise into the piston placed in the cylinder before it had been fixed in its
position. The piston rods may by a lever passing into an eye or cotter hole therein
be turned as required to screw into the piston and the correct fitting may be aided
by forming the rod end to a point. By these rods the piston is prevented rotating
and becoming loose whilst rotation of the rods is prevented by a cross head passed
over and connected to them.
The double beat valve for inlet of air employed is formed with a seat consisting
of a flange tube having inside a hollow trunk or boss held interiorily of the tube
by three or more ribs and having the boss turned and the end thereof coned the
inner edge of the tube being likewise coned. The valve of plate form fits the
coned edges of the seat and is held by ribs to a tube sliding on the boss. A pin
passes through the seat and the boss and tube of the valve, the hole in the valve

page_text: being lengthened to allow of the lift of the valve from its seat. Air passes through
the seat and between the valve plate and its tube. The seat being secured to the
inlet recess by the flange to it and the pin when the seat is fixed cannot escape.
The double beat valve for outlet of air employed is formed generally thus: The
seat is a flanged tube bored the one end having a coned projection and a central
coned boss carried by two or more wings from the projection.
The valve consists of a flange tube having its outer edge coned for the larger
Beat and the inner edge coned to the central boss. It is guided by an outer tube
connected to it by wings and this tube slides in the interior of the seat.
range of lift may be regulated by a spring which may be secured to any convenient
part of the seat.
The
In constructing the improved inlet valve with unobstruced passage way the
seat may be a plain flanged tube coned on its inner edge and the valve a plate
coned to the seat and guided by a tube fitting the bore of the seat, the plate and
tube being joined by short ribs or continuations of the tube, spaces being left
between the two through which the air may freely pass when the valve is lifted
The valve is prevented passing into the cylinder by a nut on the exterior of the
tubular part so placed as to allow of the lift of the valve and secured by a small
split pin or otherwise. Or the nut may be dispensed with and a small flat piece
of spring bent to the required shape and passing through the tubular part of the
valve resting against the outer surface of the seat
In air compressing apparatus constructed according to our invention in which
water is injected into the cylinder during the act of compression of air we perforate
.the corrugation or channel with holes at convenient portions of its circumference
thus admitting water freely from the outside water chamber surrounding the
cylinder into such channel and around the piston which piston so to speak floats on
that water and a small quantity of water so supplied may be admitted to the
cylinder at the end of each stroke by the edge of the piston being caused to recede
beyond the edge of the corrugation or channel or by a short groove in the
circumference of the piston being suitably provided.
In such cases we sometimes form the piston hollow and perforate its circumference
with suitably disposed holes or passages which thus admit water or other suitable
liquid to the interior from the said corrugation or surrounding channel whence such
liquid may escape by a hollow piston rod capable of reciprocating through the
cylinder cover in front or rear. Or we form a groove or grooves in the circum-
ference of the piston with holes or communications from such grooves leading to
the interior of the piston by which leakage of air such as already referred to may
find vent through the hollow piston rod and the corrugation or channel may be
utilized for lubricating or other uses.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
i the said Reginald Pelham Bolton and John William Hartley in the Patent
Office on the 20th March 1884.
REGINALD PELHAM BOLTON of N° 1 Victoria Villas Broxbourne in the County
of Herts Engineer and JOHN WILLIAM HARTLEY of the firm of Hartley and
Arnoux Brothers of California Works, Stoke upon Trent in the County of Stafford
Engineer "IMPROVEMENTS IN MACHINERY OR APPARATUS EMPLOYED IN COMPRESSING
AIR OR AERIFORM FLUIDS
"
Various attempts have been made to overcome the manifold difficulties and obstacles
attendant upon the successful compression of air or aeriform fluid by apparatus in an
economical manner but so far as we are aware such attempts have not met with
more than limited success and the following are some of the conditions which need
to be attained in order to successfully effect such compression. Generally the air
or aeriform fluid is compressed under high pressures in a closed cylinder or box, in
which a piston reciprocates whilst tightly fitting such cylinder and that piston is
driven to and fro by power; such movement of that piston causes air to be sucked
into and discharged from such cylinder through valves which control such passage
as water in a water-pump may be.
It is an attendant incident upon air compression that much heat is developed
and this heat is detrimental to the operation of the compressor, consequently
means for reducing or removing this heat is an important object. Another
prominent difficulty to be contended with is the tendency of the air to leak past
the piston to the reverse side of the piston in the cylinder where the heated air
thus escaping mixes with and rarefies the incoming cool air on that side of the
piston, such expansion filling that part of the cylinder with air at a tension which
when compressed by the return stroke represents a loss of compressed air as
against the same amount of compressed cool air.
It is found in practice that in the suction of air into the cylinder of air
compressing apparatus through valves even of light and unobstructed construction
it is requisite to employ power and generally it is accomplished only at the expense
of a slight vacuum in the cylinder during the instroke and this loss increases with
the increase of speed of the piston.
In order to obviate these difficulties and to effect our improvements we employ
a cylinder body of peculiar construction adapted to permit of the heat developed
by compression of the contained air being better controlled or removed. Also we
so form the cylinder body that the escaping air or leakage finds free vent to the
atmosphere at or about the middle of that cylinder enabling us to dispense with
valves for the purpose. Also we provide against loss of power through the
creation of a vacuum in the intake of air by enclosing the inlet valves in a suitable.
case or cover or cases or covers and we convey air or aeriform fluid thereto under
a sufficient pressure to prevent vacuum arising and which air pressure will suffice:
to ensure the valves being opened and the air supplied to the cylinder at all speeds.
The compression of the air so supplied we effect by a suitable adjustable injector,
provided with a small jet of high pressure air supplied to it and adapted thereby to
induce a large current of atmospheric air to enter the passage to the inlet valves of
the compression cylinder. Also we provide around either end of the piston and
within the cylinder a self-tightening ring or annulus of peculiar construction of
copper or other suitable metal, one edge or part thereof being secured to the piston
whilst the other edge splays against or towards the sides of the cylinder and
under pressure of the air is forced into close contact therewith forming a tight
joint preventing leakage. This ring of metal we cut split or divide to aid its
better operation.
We also provide double beat valves for inlet and outlet of air of light
construction adapted to large area of opening and yet possessing strength to resist,

page_text: sudden pressures and shocks in operation such as commonly are found detrimental
to those of existing construction.
Another form of inlet valve which may be employed according to our
invention has an entirely unobstructed passage way without projecting rib or boss
therein and is also of light and durable construction.
We also cool the air whilst under compression in the cylinder by surrounding the
cylinder body by a chamber containing cold air, such cold being induced by the
expansion of a small quantity of highly compressed air either in a small working
cylinder attached to the rotating or reciprocating parts or in an air injector of
suitable form leading into such chamber. This air cylinder body consists of a tube
with flanged ends and it has around the centre of its length a corrugation or
enlargement forming a channel of any suitable depth. The cylinder body is contained
in a cast iron or other suitable case and is secured by proper bolts or fastenings to
the case or cast in one piece with the casing as may be preferred. The corrugation
or enlargement of the cylinder permits of its expanding and of the bolts or fastenings
drawing the flanges tight and the cylinder body may be made of rolled sheet brass
or other suitable metal of highly conducting powers for heat without constructing
the whole cylinder covers and sides of such more expensive metal. The cylinder
body we construct of such length proportionate to the length of a solid or other
piston traversing therein, such that the one end or edge of the piston does not
travel beyond its own half cylinder, or enter the other half but on the contrary
terminates its traverse just short of or just entering the enlargement or corrugation
channel thus obviating loss of power by twice compressing the air in double stroke
in the same part of cylinder as is possible in existing arrangements, moreover by the
improved arrangement sufficient interval is given to permit of the cylinder casing
cooling at either end before recommencing compression.
In some cases we make the piston of length adapted to admit of its edge retiring
beyond the one inner edge of the circumferential channel or corrugation so as to
leave such channel open to communicate with the cylinder and the atmosphere or
to the supply pipe of air as previously described, through a pipe or trunk applied
to such channel or corrugation. By these means free air may be admitted to the
cylinder just at the extreme end of the suction or commencement of the com-
pressing stroke and to facilitate this arrangement in operation we form the edge of
the piston circumferentially rounded or tapered to prevent such edge in its traverse
catching against or injuring the edge of the corrugation or we make the edge of
the corrugation so tapered while the edge of the piston is left square.
In the case of large compressing cylinders we find it convenient to make the
corrugated part or circumferential channel casing divided into separable portions
with flanges one to each portion for convenience of connection by bolts or other
fastenings or other mode of connecting the separate portions may be employed.
In some cases we admit to the corrugation or channel cold water oil or other
suitable liquid for cooling or lubricating the piston which passes there-through.
In some cases we make one portion of the cylinder body on one side of the
mid channel or corrugation larger than that on the other side and we fit therein
a piston formed corresponding of two diameters. The larger diameter of piston
may be adapted to draw air from the atmosphere through a suction chamber or
valves of suitable construction and thence to pass such air through delivery
valves to the suction chamber at the smaller end of the cylinder the smaller
piston to which may draw and compress it to a still higher degree of compression.
The corrugation or mid channel to the cylinder enables us to overcome many of
the difficulties ordinarily attendant on the use of cylinders and, pistons of two
diameters and facilitates lubrication.
The end of the cylinder casing is divided into two recessed portions in which
inlet and delivery valves are respectively placed and a passage may be arranged to
lead from the suction valves to the side of the cylinder casting and be provided
either with a suitable opening to the atmosphere at either end or a passage from
each recessed portion may be brought to the centre of the length of the cylinder

page_text: casting and they may there form an inlet opening. The delivery recesses with
outlet valves thereto may be correspondingly arranged. Over these recesses is
bolted or secured a suitable cover or the recesses may be formed in the cover and
the cover be arranged to drop into the bored end of the cylinder casting, an
opening in the side thereof corresponding to those delivery and suction passages.
A second cover over the before-mentioned recesses is also provided or we some;
times allow the inlet recess free communication with the air bolting a small cover
over the delivery valves only in direct connection with an air reservoir or supply
by a suitable pipe or channel. The bolts employed to secure the cylinder body
may be utilised for securing the outer cover also.
When the cylinder has solid ends or the valve recesses are not made in a
removable cover we find it convenient to employ two piston rods and these rods are
passed through glands into and through the casing to be secured by screwing or
otherwise into the piston placed in the cylinder before it had been fixed in its
position. The piston rods may by a lever passing into the eye or cotter hole therein
be turned as required to screw into the piston and the correct fitting may be aided
by forming the rod end to a point. By these rods the piston is prevented rotating
and becoming loose whilst rotation of the rods is prevented by a cross head passed
over and connected to them.
The double beat valve for inlet of air employed is formed with a seat consisting
of a flange tube having inside a hollow trunk or boss held interiorly of the tube by
three or more ribs and having the boss turned and the end thereof coned the inner
edge of the tube being likewise coned. The valve of plate form fits the coned
edges of the seat and is held by ribs to a tube sliding on the boss.
A pin passes
through the seat and the boss and tube of the valve, the hole in the valve being
lengthened to allow of the lift of the valve from its seat. Air passes through the
seat and between the valve plate and its tube. The seat being secured to the inlet
recess by the flange to it and the pin when the seat is fixed cannot escape.
The double beat valve for outlet of air employed is formed generally thus: the
seat is a flanged tube bored, the one end having a coned projection and a central
coned boss carried by two or more wings from the projection. The valve consists
of a flange tube, having its outer edge coned for the larger seat and the inner edge
coned to the central boss. It is guided by an outer tube connected to it by wings
and this tube slides in the interior of the seat. The range of lift may be regulated
by a spring which may be secured to any convenient part of the seat.
In constructing the improved inlet valve with unobstructed passage way the seat
may be a plain flanged tube coned on its inner edge and the valve a plate coned to
the seat and guided by a tube fitting the bore of the seat, the plate and tube being
joined by short ribs or continuations of the tube, spaces being left between the two
through which the air may freely pass when the valve is lifted. The valve is
prevented passing into the cylinder by a nut on the exterior of the tubular part so
placed as to allow of the lift of the valve and secured by a small split pin or
otherwise. Or the nut may be dispensed with and a small flat piece of spring bent
to the required shape and passing through the tubular part of the valve resting
against the outer surface of the seat.
In air compressing apparatus constructed according to our invention in which
water is injected into the cylinder during the act of compression of air we perforate
the corrugation or channel with holes at convenient portions of its circumference
thus admitting water freely from the outside water chamber surrounding the
cylinder into such channel and around the piston which piston so to speak floats on
that water.
Our improvements relate to engines for compressing air having a piston
reciprocating to and fro in a cylinder with closed ends.
Part of our improvements relates more particularly to means of providing ready
access of free air to such cylinder; by a circumferential chamber around the body
of the cylinder which chamber may also be put to uses hereafter described.

page_text: cover and provided with a bell shaped mouth M½ out of which the air finally
passes.
The cylinder body A. is closed at each end by being fastened to the covers Q. Q¹
formed with holes to receive the valve seats a and e and cover k and also the outlet
air passages R R¹. The covers Q Q¹are bolted to the faced ends of the tank or
chamber T and facility for expansion or contraction under tightening is provided
by the corrugation C.
The tank T is provided with air passages S. S¹. corresponding to the passages R R¹
in the covers QQ¹ such passages S. S₁. serving to convey the outlet air to the
outside of the tank and thence by suitable channel or otherwise away.
Figure 2. Shows the valve seatings arranged around the cover Q and the bolts
connecting the cover Q to the cylinder body A and tank T.
V. is a pipe conveying cold air or water to the interior of the chamber T and W
is a waste or exhaust pipe for conveying the same away after use.
The arrows indicate the direction of flow of the air throughout. The tubular
inlet valve-seating a Figure 3 provided with an exterior screw thread is applied in
a correspondingly threaded hole in the cover Q.
The seating a is made of larger diameter outside the hole and is formed within
to an hexagonal or other angular shape adapted to engage a socket spanner to be
used to screw it into place or release it therefrom.
The valve 6 is a tube closed at one end which end being somewhat larger than
the outside diameter of the tube, bas upon it the coned edge which corresponds to
a similar coned edge on the seating a.
Around the tube b and below the coned edge is formed an annular groove
having drilled holes c communicating between it and the interior of the valve b.
There are two slots in the circumference of the valve b into which project small
stops & screwed in through the seating a and prevented from moving by their
position in the hole in which the seating a fits.
The outlet valve Figure 6 is applied in a seating e fixed or screwed into a hole
formed in the cover Q in a manner similar to that of the inlet valve seating just
described, the seating being provided with an internal angular recess suitable for a
spanner. The lower part of the seating has an internal coned valve-seat and a
central coned boss f somewhat deeper carried by three or more ribs.
The valve g is a tapered conical plate, provided with external and internal coned
edges corresponding to those in the seating e and boss f.
From the back of valve g projects a tube g¹ and this tube g' is joined to an outer
tubej by four ribs of light construction fitting in the seating e and forming the
guide for the whole valve.
A spiral spring is placed between the valve and the cover k surrounding the
tube g and the stop or projection k³.
The cover k is screwed into the outer part of the cover Q and has a similar
angular recess to the seating e.
The boss is of the shape shown in Fig. 9 admitting of passing of air from
tube g¹ when they are pressed together by the action of the air.
The operation of the parts is as follows:-
d
The piston K being in motion in one direction say from right to left of Figure 1
the light valves b in the cover Q will be sucked in by the slight vacuum produced
by the motion until they are arrested by the stops & meeting the ends of the slots
in which they engage. Air immediately commences to flow into the interior of
valves b and passes through holes c into the circumferential groove and between the
coned edges of a b into the cylinder A.
Spring closes the outlet valve g
At the extreme end of the stroke the edge of the flanged packing ring N passes
the edge of the corrugation C and this chamber C being full as before shown by
air drawn from the atmosphere by the injector I through pipe E such air rushes
into the cylinder A and instantly completely fills it and closes the valves 6 again
to their seats.

page_text: ..
The cylinder is now full of air ready for compression and the return stroke
commences the piston K moving now from left to right (Figure 1) The edge C¹³ is
soon passed and compression commencing soon after, the pressure begins to press
upon the interior of the metal ring N splaying it out against the cylinder all round,
with a force proportioned to the increasing pressure. Any leakage escaping past
this ring passes around the piston until it enters the groove O whence the holes P
and P' conduct it to the hollow tail rod M and so out to the open air. The heat
developed by compression communicating itself to the cylinder body A. and flanges
B. is passed by them to the cooling material outside.
The outlet valve 9 now begins to act when the force of the compression is
sufficient to lift.it against the spring l
Rising from its coned edges the air flows through tubes g¹ and j as indicated by
arrows into the passage, R from thence into the passage S and so out to the reservoir
or pipes. When almost touching the cover Q the piston K reaches the end of its
stroke, and the return stroke recommences.
It will be understood that we have described the action of one end only the other
end is at any point doing the reverse also that any other gaseous fluid than air may
be so dealt with.
Water or cold air may be pumped or run through pipo V continuously and
exhausted through pipe W keeping constant circulation around the cylinder
body A.
Water or cold air may be also pumped in through pipe E to the corrugation C
and out through another pipe similar to E on the opposite side circulating in this
manner around the piston K, or holes being provided in the piston K the water
passes therein.
We sometimes conduct the leaked air from the tail rod M by means of a fixed
pipe in which M slides passing this air through a coil of pipe in the tank T where
it is cooled and then admitted to the injector pipe I where it does duty as already
described.
Having now fully described the nature of our improvements and means adapted
for carrying the same into practical effect we would have it understood that we do
not confine ourselves to the precise details or arrangements hereinbefore described
and illustrated by the drawings but
What we do claim is,
1st The construction or adaptation of a circumferential chamber or recess from
the body of air compressing cylinders substantially as and for the purposes set
forth.
2nd The arrangement or combination of apparatus for compressing aeriform
fluid whereby a piston is capable of retreating within the edge of an expansible
chamber or corrugation for the purpose of opening communication between such
corrugation and the interior of the cylinder at the extreme end of or commencement
of the stroke substantially as and for the purposes set forth.
* 3rd The combination or arrangement of expansible corrugated chamber having a
pipe or trunk communicating with the outer air for the purpose of supplying the
corrugated chamber with oil, water, or air substantially as set forth.
4th The construction or adaptation of metallic annular packings to the pistons of
air compressors split in one or more places around the periphery thereof to admit
of expansion under internal pressure substantially as set forth.
In witness whereof I the said Reginald Pelham Bolton have hereunto set my
hand and seal this twentieth day of March in the year of our Lord One thousand
eight hundred and eighty four.
REGINALD PELHAM BOLTON. (L.S.)