Applicable for Compressing and Exhausting Air.
Year: 1888

page_text: Applicable for Compressing and Exhausting Air.
I, WILLIAM PURCELL O'NEILL of Knockmartin, Longford, Ireland, Civil Engineer,
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
stateinent
This invention relates to pumps which can be worked at high speed and which are
specially applicable for compressing and exhausting air.
These pumps are small light simple cheap and easy to maintain and may
advantageously be driven direct from petroleum engines, gas engines and steam
engines and either horizontally vertically or at an angle.
Figure 1 is a vertical longitudinal section, Figure 2 a transverse section, Figure 3
side view and Figure 4 a detail of an air compressing or exhausting pump which
may suitably be driven by a petroleum engine gas engine or other prime motor or
shafting. Figure 5 is a vertical section, Figure 6 a plan section and Figure 7 an
end view of a modified form of air compressing or exhausting pump which. is driven
by an engine or from shafting; Figures 8, 9 and 10 are end view, part sectional
end view and side view of the valve for delivering the air to and from the air
compressing pump. Figure 11 is side view and Figure 12 plan shewing such a
pump as driven directly by an engine, Figure 13 shews another such combination
and Figure 14 is a plan of same.
Referring to Figures 1 to 4 the improved air compressing or exhausting pump is
provided with an oscillating valve C which is worked by a lever C³ from an eccentric
on the main or fly-wheel shaft of the engine or from the piston rod of the pump by
suitable tappet gear as owing to the valve having the pressure in the valve chamber
equally distributed about its axis of oscillation, the valve will remain in whatever position
it is placed, and the power required to work this valve is for the same reason small.
The valve could be also driven by wheel gear from engine shaft.
The valve has a narrow slotted hole through it the full width of ports which as
shewn in Figure 1 brings both the ports of the pump into communication when they
are closed to the delivery and suction openings of the valve chamber, this takes place
when the pump piston is almost at the end of its stroke and allows the compressed air
under or in front of the piston and in the clearance spaces to pass round to the other
side of the piston, and do useful work by partially compressing the air which has just

page_text: air at once.
been sucked in, and enables the piston on its return stroke to commence drawing in
Every portion of the pump stroke is thus rendered effective for useful
work as the evil due to clearance allowances in ordinary pumps is practically done
away with and making the pump highly efficient.
The valve as can be seen from Figure 2 is simple and cheap to make it is capable
of being packed, removed or replaced by another in a few minutes without in any
way interfering with the back pressure valve X' all these things being matters of great
importance.
The pump cylinder is thoroughly jacketed with circulating cold water as indicated
by the arrow and is thus rendered very suitable as a dry air pump.
Referring to the modified form and arrangement of pump shewn in Figures 5, 6
and 7 the gas petroleum or steam engine works by the connecting rod A' the crank A²
on the shaft A³, which by the crank A* and connecting rod A³ transmits reciprocating
motion to the piston of the air compressing or exhausting pump cylinder B. The air
enters at B into a chamber containing two pulleys B2 united by an endless band B³
and caused to revolve continuously by a pulley B driven from a pulley B' in the
shaft A³. The lower part of the chamber is filled with water and the constantly
moistened band B³ which may be of canvas or flannel thus imparts moisture to the
air, which passes thence by a pipe B to the circular oscillating valve ( shewn
separately in Figures 8, 9, and 10. This valve has four ports C₁ recessed into one
side and two ports (2 recessed into the opposite side so as when oscillated to cause
alternate supply to and exhaust from each end of the cylinder B which has corre-
sponding ports. The valve is oscillated by the eccentric and rod C and the lever C³.
The valve has also a through port C3 which operates relatively to two corresponding
ports in the body of the cylinder that the air compressed on one end of the cylinder
piston passes through the said port C³ to the other side of the piston a little before
(say within one eighth of) the stroke. I thus utilize the power of the compression
while causing a more even motion. The cylinder B is formed with a jacket through
which cooling water is run from a water tank on its way to the cylinder of the
petroleum or gas engine or from any other tank or source. The means for moistening
the air may be omitted but are advantageous if the compressed air on its way to
the cylinder wherein it is to act receives additional heat so as to expand it in bulk
and form the moisture into high steam. The most highly compressed air passes off
by the pipe E.
In Figures 11 and 12 the air compressing pump is shewn combined with a
gas petroleum or steam engine by means of a slot crank on a common bed plate or
frame.
In Figures 13 and 14 the crank of the engine follows the crank of the pump so
that the latter is doing its maximum work when the engine is at its powerful
point.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is
The constructions of pump with special reference to the means for distributing.
the fluid to and from each end of the pump cylinder end substantially as set
forth.