IMPROVEMENTS IN APPARATUS FOR COMPRESSING AIR OR OTHER ELASTIC FLUID
Year: 1880

page_text: LETTERS PATENT to Peter Brotherhood, of No. 25, Ladbroke Gardens, Notting
Hill, in the County of Middlesex, for an Invention of "IMPROVEMENTS IN
APPARATUS FOR COMPRESSING AIR OR OTHER ELASTIC FLUID."
PROVISIONAL SPECIFICATION left by the said Peter Brotherhood at the
Office of the Commissioners of Patents on the 7th June 1880.
PETER BROTHERHOOD, of No. 25, Ladbroke Gardens, Notting Hill, in the County
of Middlesex. "IMPROVEMENTS IN APPARATUS FOR COMPRESSING AIR OR OTHER
ELASTIC FLUID."
My Invention relates to apparatus for compressing air or other clastic fluid by
what is known as stage or successive pumping, the object which I have in view being
to arrange the successive pumps in simple and compact form, and to provide means
for effective cooling of the fluid while it is undergoing compression. For this purpose
I provide a vertical cylinder, the upper part of which is of larger diameter than
the lower part, the two parts being separated by a ring of internal diameter, smaller
than the lower part. The upper part is fitted with a piston which is connected
by a trunk or plunger to a piston which fits the lower part of the cylinder; both
pistons are provided with leather or other suitable packing, and the ring separating
the two parts of the cylinder is also provided with packing through which works
the trunk or plunger that connects the two pistons. The cylinder cover is made
with an annular suction valve by which fluid enters the upper part of the cylinder
during the downstroke of the piston. Through the upper piston there are passages
fitted with valves opening downwards, by which, during the upstroke of the piston,
the fluid passes into the annular space below the upper piston. In the trunk or
plunger there are also passages fitted with valves opening downwards, by which,
during the downstroke of the piston, the fluid passes to the annular space below the
separating ring and above the lower piston. From this annular space there is a
passage fitted with a discharge valve, by which, during the upstroke of the piston,
the fluid is discharged, having undergone three stages of compression; first, in the
space above the upper piston; secondly, in the annular space below it; and thirdly,
in the annular space below the separating ring and above the lower piston. For
the purpose of cooling the fluid during compression I provide in the hollow space in

page_text: the interior of the trunk or plunger two stationary tubes, one within the other,
having an annular space between them. These tubes are fixed to the cover of the
cylinder, and the upper piston is provided with packing which works over the outer
of the two tubes. At the bottom of the annular space between the tubes there is a
valve opening downwards, by which, during the downstroke of the piston, water or
other cold liquid supplied to the outer tube at its upper end passes into the internal
cavity of the trunk or plunger. Also at the top of the inner tube there is a valve
opening upwards, by which, during the upstroke of the piston, the liquid is
discharged from the cavity of the trunk or plunger. Thus at every stroke of the
piston the liquid is caused to circulate through the trunk or plunger, cooling the
same.
The liquid is discharged into a tank or cistern enclosing the cylinder so as to cool
its exterior, and in this tank there is a coil of pipe through which the compressed
fluid flows on its way to the reservoir or receptacle in which it is to be stored.
The piston may be worked by a crank or eccentric on a revolving shaft below, or
by direct connection with the piston of a steam cylinder.
It is of advantage to arrange several compressing pumps such as I have described
to work from cranks on one shaft, these cranks being set so that the strokes of the
several pumps succeed at equal intervals during each revolution.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Peter Brotherhood in the Great Seal Patent Office on the 5th
November 1880.
PETER BROTHERHOOD, of No. 25, Ladbroke Gardens, Notting Hill, in the County of
Middlesex. "IMPROVEMENTS IN APPARATUS FOR COMPRESSING AIR OR
ELASTIC FLUID."
OTHER
My Invention relates to apparatus for compressing air or other elastic fluid by
what is known as stage or successive pumping, the object which I have in view
being to arrange the successive pumps in simple and compact form, and to provide
means for effective cooling of the fluid while it is undergoing compression. For
this purpose I provide a vertical cylinder, the upper part of which is of larger
diameter than the lower part, the two parts being separated by a ring of internal
diameter, smaller than the lower part. The upper part is fitted with a piston
which is connected by a trunk or plunger to a piston which fits the lower part of
the cylinder; both pistons are provided with leather or other suitable packing, and
the ring separating the two parts of the cylinder is also provided with packing
through which works the trunk or plunger that connects the two pistons. The
cylinder cover is made with an annular suction valve by which fluid enters the
upper part of the cylinder during the downstroke of the piston. Through the
upper piston there are passages fitted with valves opening downwards, by which
during the upstroke of the piston the fluid passes into the annular space below the
upper piston. In the trunk or plunger there are also passages fitted with valves
opening downwards, by which during the downstroke of the piston the fluid passes
to the annular space below the separating ring and above the lower piston. From
this annular space there is a passage fitted with a discharge valve, by which, during
the upstroke of the piston, the fluid is discharged, having undergone three stages
of compression; first, in the space above the upper piston; secondly, in the annular
space below it; and thirdly, in the annular space below the separating ring and
above the lower piston. For the purpose of cooling the fluid during compression
I provide in the hollow space in the interior of the trunk or plunger two stationary
tubes, one within the other, having an annular space between them. These tubes
are fixed to the cover of the cylinder, and the upper piston is provided with packing
which works over the outer of the two tubes. At the bottom of the annular
space between the tubes there is a valve opening downwards by which, during the
downstroke of the piston, water or other cold liquid supplied to the outer tube at
its upper end passes into the internal cavity of the trunk or plunger. Also
at the top of the inner tube there is a valve opening upwards, by which, during the
upstroke of the piston, the liquid is discharged from the cavity of the trunk or
plunger. Thus at every stroke of the piston the liquid is caused to circulate
through the trunk or plunger, cooling the same.
The liquid is discharged into a tank or cistern enclosing the cylinder so as to
cool its exterior, and in this tank there is a coil of pipe through which the
compressed fluid flows on its way to the reservoir or receptacle in which it is to be
stored.
The piston may be worked by a crank or eccentric on a revolving shaft below,
or by direct connection with the piston of a steam cylinder. It is of advantage to
arrange several compressing pumps such as I have described to work from cranks
on one shaft, these cranks being set so that the strokes of the several pumps
succeed at equal intervals during each revolution.
The accompanying Drawing represents a vertical section of a compressing
apparatus according to my Invention. The upper part A of the cylinder is fitted
with a trunk piston B connected to the piston B' which works in the lower part A¹

page_text: of the cylinder; the two parts of the cylinder are separated by the ring A² through
packing in which the trunk works. In the cylinder cover is fitted the annular
suction valve C beld up to its seating by springs c; in the piston B are passages
fitted with valves D opening downwards, these passages communicating with the
annular space a and other passages leading to the annular space a¹ fitted with
valves E opening downwards. From the space a¹ a passage fitted with the
discharge valve F communicates with the pipe coil G. The cylinder and coil are
enclosed within a tank H containing water. To the cylinder cover are fixed the
concentric tubes I and J, forming passages provided with the supply and discharge
valves K and L for effecting circulation of water through the interior of the
piston as above described; M is a relief valve. As the pistons descend air is
drawn through the suction valve C into the upper part of the cylinder, and the air
in the annular space a is forced through the valves E into the smaller annular
space a¹.
As the piston ascends the air in the space above it is forced through
the valves D into the annular space a, and the air in the annular space a¹ is
discharged through the valve F and the coil G to the reservoir or other vessel
provided for its reception. By the descent and ascent of the piston water is drawn
in through the valve K and discharged through the valve L, cooling the interior of
the piston.
Having thus described the nature of my Invention and in what manner the
same is to be performed, I claim,―
The use of apparatus for compressing air or other elastic fluid, constructed and
operating as herein described with reference to the accompanying Drawing.
In witness whereof, I, the said Peter Brotherhood, have hereunto set my
hand and seal, this Fifth day of November, in the year of our Lord One
thousand eight hundred and eighty.
DERED PROTHERWOOD
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