Improvements in Gas Pumps or Compressors.
Year: 1897

page_text: Date of Application, 9th June, 1897
Complete Specification Left, 9th Mar., 1898-Accepted, 4th June, 1898
PROVISIONAL SPECIFICATION.
Improvements in Gas Pumps or Compressors.
I, JAMES KEITH, Assoc. M. Inst. C.E., of 27, Farringdon Avenue, in the City
of London, Gas, Hydraulic, Heating, and Ventilating Engineer, do hereby declare
the nature of this invention to be as follows: :-
This invention relates to apparatus for increasing the pressure of gas or for
forcing air and it has for its object the economy of the water used in working
such apparatus.
The improved apparatus comprises a pump which consists of a cylinder pro-
vided with an annular water space into which a small gas holder dips. The water
acts as a seal and when the holder is moved up and down by means of the water
motor forming part of the apparatus the gas or air is alternately drawn in and
expelled above or below the holder or float. The spaces above and below the float
are connected by means of ports to a valve chamber having suitable inlet and
discharge valves for each space. The annular water space is kept charged with
water from the exhaust of the motor which is led into the bottom of this space
and overflows into the centre of the cylinder. This water fills up the interior of
the cylinder to the height of an overflow pipe situated in the cylinder and pro-
vided with a deep trap to prevent the gas from being blown out; and the overflow
water is discharged from the trap at about the level of the overflow in the
cylinder. The water in the annular space rises and falls alternately on the inside
and outside of the holder to a height equal to the difference in pressure on the
inside and outside of the holder.
The water motor is of a double acting differential type such as that described
in the Specification of my Application for Patent No. 20573/96 and acts in a
similar manner. The pressure water acts continuously on the bottom side of the
piston the top side of which is exposed alternately to pressure and exhaust by
means of a main piston valve which is again controlled by an auxiliary valve.
This auxiliary valve is moved at the end of each stroke by means of a cap nut on
the main piston acting on the tappet rod connected to said valve. The auxiliary
valve communicates with the pressure and exhaust by two separate copper tubes
cast in the body of the cylinder, and with the main valve by a third tube. The
pressure water communicates with a circle of small holes or ports in the auxiliary
valve chamber and the exhaust tube communicates with a second series of ports,
each series being alternately brought into communication with one end of the
main valve to admit pressure water or exhaust the same therefrom. The end of
the main piston valve is exposed to pressure water when the small inlet ports are
in communication with the small ports leading to the main valve chamber and
therefore the main valve is forced down to the end of its chamber as one end of
the piston valve is greater in area than the other end on which the pressure is
also acting in an upward direction. The main valve is then in such a position as
to open the top of the main piston to exhaust and the motor will then make an
upward stroke owing to the pressure which is always acting on the bottom side of
the piston. At the top of this stroke the auxiliary valve is pushed up until the

page_text: small exhaust ports are in communication with the ports leading from the back
end of the main valve chamber and the inlet ports are closed. This allows the
water at the back of the main piston valve to pass to exhaust and the main valve
is reversed by the pressure water acting underneath. The pressure water is now
on both sides of the cylinder piston and the down stroke is made because the top
side is of greater area than the bottom side; and on reaching the bottom of its
stroke the auxiliary valve is again pulled down by means of the cap nut and the
main valve also moves by the action of the pressure water.
The motor is regulated by means of a small weighted gas holder into which the
compressed gas is pumped and as the holder rises it is arranged to act on the lever
of a regulating valve which is fixed on the water pipe leading to the motor, clos-
ing it when rising and opening when falling according to consumption. The waste
water which flows from the overflow of the pump is made to run into the tank
in which the holder floats and overflows finally at the other side so as to keep it
properly charged with water and keep it pure.
The regulating valve may be of either of the forms described in Letters Patent
No. 260 of 1895 granted to me.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
Saint Vincent Street, Glasgow, Agent for the Applicant
I, JAMES KEITII, Assoc. M. Inst. C.E., of 27, Farringdon Avenue, in the City
of London, Gas, Hydraulic, Heating, and Ventilating 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 statement;
This invention relates to apparatus for increasing the pressure of gas or for
forcing air and it has for its object the economy of the water used in working
such apparatus.
The improved apparatus consists of a compressing pump actuated by a water
motor the pump part being made in the form of a gas holder or bell dipping in
an annular water space formed around a closed cylinder and serving by its recipro
cation within the cylinder to alternately draw in and expel gas or air at either
end, being thus double acting, (but it may be single acting) the gas or air passing
thence to a gas holder or receiver loaded to maintain the desired pressure. The
gas holder or receiver which rises and falls according as the gas drawn off for
consumption is connected to a regulating cock or valve which controls the admis-
sion of water to the motor. When the holder rises on being filled with gas the
water is cut off from the motor and as the holder falls the valve is more or less
opened to admit water to actuate the motor whereupon the compressor again
charges the gas holder. The pump is in this way actuated only to maintain the
supply of gas in the holder at a pressure determined by the load upon it, and only
the water passing into the motor while it is in operation is used.
In the accompanying drawings which illustrate the invention, Figure 1 is a
vertical section of the improved apparatus, Figure 2 is an elevation at right angles
to Figure 1, Figure 3 is a plan of the same, and Figure 4 is a vertical section to
an enlarged scale of the motor shown in Figure 1. Figures 5 and 6 are sectional

page_text: Views on the lines, and yy, respectively, or valve arrangements nerein-
after referred to.
As represented in these drawings, the improved apparatus comprises a pump
which consists of a cylinder A provided with an annular water space a which is
formed between the cylinder proper and an inner open ended cylinder A¹, and
into which water space a small gas holder B dips. The water in a acts as a seal
and when the holder B is moved up and down by means of the water motor C
forming part of the apparatus and hereinafter described, the gas or air to be com-
pressed is alternately drawn in and expelled both above and below the holder or
Hoat B, the gas being drawn through inlet pipes D, G, into the cylinder A and
expelled through the same pipes. The spaces above and below the float B are
connected to a valve chamber E having suitable inlet valves e, e¹, and discharge
valves e, e, for each space. The upper side of the cylinder A is connected by
a pipe G and port G₁ to the part of valve box E containing the suction and
delivery valves e, and e³, respectively. Similarly, the under side of the cylinder is
connected by a stand-pipe D and port D¹ cast in the base, to a separate compart-
ment of the valve box containing the suction and delivery valves e, e². The
annular water space a is kept charged with water from the exhaust pipe c of the
motor which is led into the cylinder near the bottom of this space and overflows
into the centre of the cylinder A. This water fills up the interior of the cylinder A¹
to the height of an overflow pipe F situated in the cylinder and forming a deep
trap to prevent the gas from being blown out; and the overflow water passing
in the direction shown by the dotted arrows, Fig. 1, through the pipe F is or may
be discharged from the trap at about the level of the overflow in the cylinder.
The water in the annular space a rises and falls alternately on the inside and
outside of the holder to a height equal to the difference in pressure on the inside
and outside of the holder. The gas supply is connected to the two suction
valves e, e¹, and the two delivery valves e³, e³, discharge by a port j and stand-
pipe J into a gasholder L placed alongside the cylinder and loaded to the desired
pressure by a ring M on the bottom and supplementary weights N on the top,
these top weights serving to adjust the pressure. The pump part is operated by
the water motor C fixed directly on the top of cylinder A.
The water motor C is of a double acting differential type such as that described
in the Specification of my Application for Patent No. 20573/96 and acts in a
similar manner. The pressure water admitted at O acts continuously on the
bottom side of the piston P the top side of which is exposed alternately to pres-
sure and exhaust by means of a main piston valve Q which is again controlled
by an auxiliary valve R. This auxiliary valve R is moved at the end of each
stroke by means of a cap nut p on the main piston P acting on a tappet rod T
connected to said valve R. The auxiliary valve R communicates with the pres-
sure and exhaust by two separate copper tube's S, S¹, cast in the body of the
cylinder, or otherwise fitted, and with the main valve Q by a third tube S³. The
pressure water is admitted at r to the auxiliary valve chamber R2 and communi-
cates with a circle of small holes or ports r¹ in a liner R' fitted in the auxiliary
valve chamber R2 and the exhaust tube S¹ communicates with a second series of
ports in said liner. The upper end of the main piston valve Q is exposed to
pressure water when the small inlet ports r are in communication with the small
ports leading to the main valve chamber and therefore the main valve Q is
forced down to the end of its chamber as the upper end of the piston valve Qis
greater in area than the lower end on which the pressure is always acting in an
upward direction. The main valve Q is then in such a position as to open the
top of the piston P to the exhaust pipe c through ports q and the piston P
of the motor will then make an upward stroke owing to the pressure which is
always acting on the bottom side of the piston P. At the completion of this stroke
the auxiliary valve R is pushed up until the small exhaust ports are in com-
munication with the ports 1 leading from the top end of the main valve chamber
and the inlet ports rare closed. This allows the water at the top of the main

page_text: piston valve Q to pass to exhaust through the tubes S2, S¹, and the main valve Q
is reversed by the pressure water acting underneath. The pressure water is now
admitted to both sides of the cylinder piston P, being always on the underside
and passing by the ports q to the upper side, and the down stroke is made because
the top side of said piston is of greater area than the bottom side. On reaching
the bottom of the stroke of the piston P the auxiliary valve R is again pulled
down by means of the cap nut p, and the main valve Q also moves by the action
of the pressure water.
The motor C is regulated by means of the small weighted gas holder L into
which the compressed gas is pumped and as the holder L rises it is arranged to
act on the lever U of a regulating valve or cock V which is fixed on the water
pipe W leading to the motor, the cock V being closed when the holder L rises
and being opened when the holder falls according to consumption of the gas. The
waste water which passes from the overflow pipe F of the pump cylinder A is
made to run into the tank L' in which the holder L floats, and overflows finally
at X so as to keep it properly charged with water and keep it pure.
Instead of the regulating cock V a regulating valve of either of the forms
described in Letters Patent No. 260 of 1895 may be employed.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what I
claim is:
-
1. A gas pump or compressor the several parts of which are constructed and
arranged to operate substantially as described.
2. The combination with a compressing pump actuated by a water motor of
a loaded gas holder or receiver whereinto the gas or air from the pump is dis-
charged, the said gas holder being connected to operate a regulating valve on the
motor supply pipe to control the admission of water to the motor and automati-
cally actuate the pump as the gas supply is drawn off substantially as described.
3. The combination with a cylinder provided with an annular water space of
a gas holder actuated by a water motor and serving as a compressing pump sub-
stantially as described.
4. The combination with a gas compressor of a water motor constructed and
arranged to operate substantially as described.
Dated this 8th dow of Manal 1000
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents,
62, Saint Vincent Street, Glasgow, Agent for the Applicant.