Improvements in Direct-acting Pumping Engines.
Year: 1893

page_text: Date of Application, 5th Sept., 1893-Accepted, 14th Oct., 1893
COMPLETE SPECIFICATION.
[Communicated from abroad by CHARLES CAMPBELL WORTHINGTON, of Irvington,
in the State of New York, United States of America, Mechanical Engineer.]
Improvements in Direct-acting Pumping Engines.
I HENRY EDWARD NEWTON of The Office for Patents, 6 Bream's Buildings,
Chancery Lane in the County of London, Patent Agent, 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 that class of direct-acting engines in which one or more
compensating cylinders and pistons are employed to act in opposition to the main
piston or pistons during one part of the stroke, and in conjunction therewith during
another part of the stroke. The motor fluid which operates upon the compensating
pistons in engines of this class, may be steam, air, water, or other fluid. Where air
or water is employed as the motor fluid, the necessary pressure is preferably
derived either directly from the force main of the pump, or through an accumulator,
by which this pressure is increased. The improvements constituting the present
invention are especially applicable to those engines in which the pressure for the
compensating cylinders is thus derived from the force main of the pump, the object
being to provide a construction by which the pressure shall be dependent on, and
vary gradually with, changes in the force pressure, and shall not be increased
suddenly by a sudden increase in force pressure, but shall be relieved quickly upon
a sudden reduction of force pressure.
In direct-acting pumps employing compensating cylinders, the pressure in the
force main is subject to sudden variations due to various causes. Any sudden
increase in the force pressure, if transmitted directly to the accumulator and com-
pensating cylinders, produced an undesirable shock upon the compensating cylinders,
and in case of a sudden fall of the force main pressure, the compensating cylinders,
if continued under full pressure, cause a sudden increase of speed and shock in the
engine.
A simple construction is provided by which the pressure of the accumulator and
compensating cylinders is drawn from, and depends upon, the force main, and at the
same time all difhculty in respect to sudden changes avoided, by providing a valve
controlling the pressure in the compensating cylinders, and controlled by the
pressures in the compensating cylinder or connections and the force main, so as to
be opened to relieve the pressure in the force main, and by providing a small
constant connection between the force main and compensating cylinders, so that the
pressure in the compensating cylinders will rise or fall gradually with the pressure
in the force main, but a sudden increase in the force pressure will not be
transmitted to the compensating cylinders.
An air chamber is preferably employed, through which the force pressure is
transmitted to the compensating cylinders and also a valve constructed to relieve
the pressure in the air chamber when opened, and controlled by the pressures in
the air chamber and force main, so as to be closed while the pressure in the force
main is equal to or greater than that in the air chamber, but to be opened on a
sudden decrease in the force pressure below that in the air chamber and relieve the
pressure in the air chamber, a small constant connection between the force main and
air chamber being provided, through which water may pass gradually. By this
construction, any increase of force pressure is not transmitted to the compensating
cylinders, except by the gradual passage of water from the force main to the air
chamber, so that any sudden rise of the force pressure produces no shock on the
compensating cylinders, while the pressure in the compensating cylinder, or the
accumulator, when the latter is used, is normally that of the force main, as any

page_text: continued rise of the pressure is transmitted by the passage of water through the
small connection and the pressure air chamber gradually to that in the force main.
Upon a sudden fall of the force pressure, the valve controlling the pressure in the
air chamber and the pressure in the air chamber, and consequently in the com-
pensating cylinders, is relieved by the escape of the air, or the water, by which the
air is held under compression, the construction being preferably so arranged that
the air is allowed to escape immediately on the opening of the valve, or on the
return of a small amount of water from the air chamber to the force main.
It is evident that this invention may be embodied in constructions differing
widely, and that when the preferred construction employing an air chamber is used,
the air chamber may be mounted on the force main, or connection between the
force main and air chamber be made in any suitable manner, and that the air
chamber also may form a part of the accumulator commonly employed in such
constructions, or be connected thereto in the usual manner. It is preferable, how-
ever, that the air chamber be connected with the force main in such a manner that
the water may be allowed to rise in the air chamber as the pressure of the air
decreases, so as to preserve the pressure in the air chamber, and that the valve
controlling the pressure in the air chamber be normally covered with water, to
prevent leakage of the air, while at the same time but a small body of water need
be discharged before the air is allowed to escape, so that the pressure in the air
chamber may be quickly relieved, and a construction is devised fulfilling these
conditions, which it is preferable to use, and which in itself forms a part of this
invention.
For a full understanding of this invention, a detailed description of a construction
embodying the invention in its preferred form, and certain modifications thereof, will
now be given, reference being had to the accompanying drawings, in which the
invention is shown as applied to a duplex pumping engine with compensating
cylinders of substantially the general form and arrangement now well known as
Worthington's pumping engines. It will be understood, however, that the invention
is applicable generally to pumping engines employing compensating cylinders.
In the accompanying drawings,
Fig. 1 is a longitudinal section of a duplex engine embodying this invention, the
section being taken between the pump cylinders.
Fig. 2 is a detail vertical section of the parts embodying the invention.
Fig. 3 is a section on the line 3, 3 of Fig. 2, looking downward.
Fig. 4 is a section on the line 4, 4 of Fig. 2, looking upward.
Figs. 5 to 8 show modifications.
Referring to said drawings, it will be understood that A is one of the steam cylinders,
and B one of the water cylinders of the pump, and C, D respectively the usual suction
and force mains; E is the accumulator of the usual construction, from which
pressure is transmitted through the pipe F to compensating cylinders G connected
to the cross head H of the extended piston rod I,-all these parts being constructed
and operating as is common in this class of engine.
Referring now to the parts embodying the invention, as shown in Figs. 1 to 4,
K is a casting mounted on the force main in the position of the usual air chamber,
and forming the air chamber from which the pressure in the accumulator is drawn
by a pipe L communicating therewith near the top. This pipe L may pass outside
the chamber K, but is preferably extended downward through the chamber and
force main. D, and thence to the accumulator E between the cylinders on opposite
sides of the pump. A pipe M enters the upper part of the chamber K, and forms
the air supply pipe through which air is forced to the pressure desired by an air
compressor X, shown in diagram. Between the air chamber K and the force
main D, is a plate N, which forms the base of the chamber K, and is this plate N
is secured a pipe O, preferably of a considerable size, as shown, and extending
nearly to the top of the chamber, this pipe being provided near its lower end with
smail openings 1 through which water may pass. The air chamber K communicates
with the force main directly and constantly through small openings 2 in the plate N,

page_text: so that the pressure in the chamber and force inain are maintained normally the
same. The pipe O communicates with the force main D through a check valve 3
opening toward the force main, and spring-pressed by a spring 4 resting against a
cap 5, which is carried by a rod 6, screw-threaded in a bracket 7, so as to be
adjustable therein to vary the tension of the spring 4, this rod 6 being extended
through the wall of the force main and provided with a hand wheel 8 outside the
force main, for the purpose of adjustment. By this construction, the valve 3 is kept
normally closed by the pressure of the spring 4, the pressure in the force main and
air chamber being the same, and the pressure of the spring may be adjusted so as
to regulate, as desired, the decrease of pressure allowed in the force main, before the
valve will be opened by the excess of pressure in the air chamber.
The operation of the construction will be understood from a brief description.
The pressure in the force main D and air chamber K are normally the same, the
water passing from the force main D through the small openings 2 in plate N, and
rising in the air chamber as the pressure of the air in the upper part of the
chamber decreases, so as to preserve a uniform pressure, the check valve being
closed by the pressure of spring 4, while the pressure in the force main and
chamber are substantially the same, or the pressure in the former the greater, any
permanent increase of pressure in the force main therefore being transmitted
gradually to the air chamber K by the water passing slowly from the force main
into the air chamber through the openings 2 and compressing the air therein, while
the air chamber does not respond quickly to such increase, so that a sudden rise
of the force pressure is not felt in the compensating cylinders, and no shock is
produced thereon.
The pressure of the spring 4 is preferably so adjusted that the valve 3 does not
open upon a slight fall in the pressure of the force main, and the pressure is
equalized again only by the passage of the water from the air chamber to the force
main through the opening 2, but if the force pressure fall substantially, and below
the point for which the spring is adjusted, the check valve 3 is opened against the
pressure of spring 4 by the excess of pressure in the air chamber, and the small
amount of water in the pipe O flows out at once, and immediately upon the emptying
of the pipe O, some of the air in the cylinder K escapes through the pipe O, the
water from the lower part of the air chamber passing through the openings 1 into
the pipe O, so slowly as not to interfere with the escape of air. The pressure in the
air chamber is thus relieved, and the effect of the compensating cylinders reduced
almost instantaneously in accordance with the fall of the pressure in the force main.
Upon the reduction of the pressure in the air chamber to substantially that in the
force main, the check valve 3 closes.
While the construction thus far described embodies the invention in its preferred
form, it is evident that this construction may be varied, and that other constructions
embodying the invention may be readily devised. Thus, the openings 1 in the
pipe O may be omitted, so that the air escapes immediately upon the opening of
the valve, and it may be found that the water will still seal the valve sufficiently to
prevent the leakage of air, but the sealing is assured by the use of the holes, while
the relief of the pressure in the air chamber is not substantially delayed. The
valve construction may be used without the pipe O, and all the water in the air
chamber pass out before the air, and this construction is efficient if the water be kept
at a low level in the air chamber, so as to secure a quick relief, but this requires
constant or frequent supply of air to the air chamber.
In Figure 5, I have shewn a very simple construction, in which the arrangement
of the air chamber K on the force main and of the pipes L, M, is substantially the
same as that described, except that the pipe L is led to the accumulator outside
the air chamber. In this figure, however, in place of the plate N and parts carried
thereby for controlling the pressure in the air chamber, is shewn a simple disc
valve 8, which carried by a rod 9, mounted to rock in the base of the air chamber,
and provided, outside the latter, with a crank arm 10, carrying an adjustable
weight 11, by which the valve is held normally closed, when the pressure in the

page_text: force main and air chamber are substantially the same, this weight 11 corresponding
to the spring 4 in the construction previously described. The valve 8 is placed
upon the rod
in such a manner as to open against the pressure of the weight 11,
on a fall of pressure in the force main D, and is made to fit loosely, when closed, so
as to allow the gradual passage of water between the air chamber and force main,
as in the case of openings 2 in the construction previously described.
The operation of this construction is identical with that previously described,
except that the pressure in the air chamber is relieved by the escape of the
air only after all the water in the air chamber has passed out, the water being
kept preferably at a low level in the air chamber, as shewn, so as to secure a quick
relief.
With this construction, also, in which the opening of the valve affords space for
the free escape of the water, it will be found practicable to connect the pipe L with
the chamber K below the normal level of the water in the air chamber, so that the
pressure is transmitted from the air chamber to the accumulator, or compensating
cylinder, through a column of water, and the pressure is relieved only by the
escape of the water from the air chamber, the air being retained within the air
chamber, but allowed to expand by the escape of water. It is evident, however,
that the constructions in which the air is allowed to escape are much preferable, as
a quicker relief may be given, and, moreover, upon the closing of the valve, the
pressure is more quickly equalised by the return of water through the passages 2,
the amount to be returned being less.
It is not necessary that the pressure in the air chamber should be relieved by the
escape of water or air from the air chamber to the force main, but means may be
provided by which the air is allowed to escape to the atmosphere, independently of
the level of the water in the air chamber, and in place of using a check valve
between the air chamber and force main, the valve controlling the pressure
in the air chamber may be controlled by a weighted or spring-pressed piston,
subjected on opposite sides to the pressures in the air chamber and force main, so
as to hold the valve closed when the pressure in the force main is equal to, or
greater than, that in the air chamber, but to be actuated to open the valve on a
fall of pressure in the force main.
°
In Figure 6, I have shewn such a construction in which the base plate of the
air chamber K has mounted therein a short cylinder 12 open at opposite ends to
the force main and air chamber, and in which moves a piston 13 subjected on
opposite sides to the pressure in the force main and air chamber. This piston is
connected by a rod 14 extending upward through the air chamber to a piston
valve 15 constructed to allow the escape of air, when the valve moved downward to
a certain point, but to prevent the escape of air when the valve is above this point.
The spring 4, cap 5, rod 6, bracket 7, and hand wheel 8, of the construction shewn
in Figures 1 to 4, are used, the spring pressing against the lower side of the
piston 13, so as to keep the valve 15 normally closed, to prevent the escape of air,
and the base plate is provided with the small openings 2, to permit the gradu!
passage of water between the air chamber and force main.
In the operation of this construction, the piston 13 is normally held in position
by the spring 4, so that the valve 15 is always closed, to prevent the escape of air
from the air chamber K, when the pressure in the force main D is equal to, or
greater than, that in the air chamber, the piston 13 being moved by a slight
variation of pressure, but not so as to open the valve. Upon a sudden fall of
pressure in the force main D below the point for which the spring 4 is adjusted,
however, the piston 13 is moved downward by the excess of pressure in the air
chamber, so as to open the valve 15, and allow the escape of air from the air
chamber, to relieve the pressure therein. It will be seen that by this construction
an immediate relief in the air chamber is secured, this being independent of the
amount of water in the air chamber. The constructions previously described, how-
ever, will generally be found preferable, as the leakage of air is prevented by the
water seal.

page_text: In Figure 7, I have shewn a construction in which the air chamber Q is
connected to the force main D by a pipe R, having thereon a spring-pressed check
valve 16, opening toward the force main, and corresponding to the valve 3 of the
constructions shewn in Figures 1 to 4, a by-pass 17 being provided for the gradual
passage of water between the force main and air chamber, and this by-pass being
controlled by throttle 18, so as to be adjustable at will. A valve 19, to permit
the escape of air from the air chamber to the atmosphere, is used, this valve being
controlled by a float 20, so that the valve is always closed when the pressure in the
force main is equal to or greater than that in the air chamber, and the water in
the latter held at or above a certain level, while upon the fall of the water and float
below that level, consequent upon a fall of pressure in the force main, the valve is
opened, and the pressure relieved by the escape of air from the air chamber. A
common gauge 21 is preferably provided to enable the height of the water in the
air chamber to be constantly seen, so that the water may be kept at the proper
level by the supply of air through pipe N.
In all the constructions thus far described, the pressure from the air chamber
may be transmitted directly to the compensating cylinders, instead of through
an accumulator, as shewn in Figs. 1 to 4. It is evident, moreover, that where an
accumulator is employed, the air chamber may be in the accumulator, and the force
main connected directly with the latter.
In Figure 8 there is shewn such a construction, in which the upper part of the
accumulator E forms the air chamber, and is provided with the pipe M, through
which air may be forced into the accumulator, as in the case of the air chamber K
in the construction previously described, and the force main connects with the
accumulator above the piston 22 in the same manner as shewn in Figure 7, by the
pipe R, check valve 16, and by-pass 17, controlled by throttle 18.
The operation of this construction will be understood without further description,
it being evident that the pressure in the accumulator is relieved by the escape of
water through the pipe R, when the check valve 16 is opened by the excess of
pressure in the air chamber, and by the escape of the air after the water has
reached the level of the pipe R. The pressure may be relieved enough by the
escape of the water alone, and consequent expansion of the air, as previously
described in connection with Figure 5.
While air has been described as the elastic fluid and the term air chamber used
to designate the part through which the force pressure is transmitted to the
compensating cylinders, it will be understood that any other elastic fluid may be
used for this purpose, and by the term air-chamber it is intended to cover a
chamber for applying elastic fluid pressure in the manner described, independently
of the character of the fluid.
While the preferred construction only is shewn embodying (the invention &
certain modifications thereof, it will be understood that other modifications may
readily be made by those skilled in the art, without departing from this invention,
which is not intended to be limited to any of the specific constructions shewn.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me from abroad, and in what manner the same is to be
performed, I declare that what I claim is :-
1. The combination with the force main of a pumping engine and a compensating
cylinder or cylinders deriving pressure from the force main, and having a constant
connection with the force main, to permit the gradual transfer of pressure between
the force main and compensating cylinder or cylinders, of a valve controlled by the
pressure on the force main side, tending to close the valve, said valve being
constructed and arranged to relieve the pressure in the compensation cylinder or
cylinders, when opened, substantially as described.
2. The combination with the force main of a pumping engine and a compensation
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensating cylinders, having a constant connection

page_text: with the force main, to permit the gradual passage of water between the air
chamber and force main, and a normally closed valve constructed and arranged to
relieve the pressure in the air chamber, when opened, and controlled by the pressure
in the force main and air chamber, the pressure in the force main tending to close
the valve, substantially as described.
3. The combination with the force main of a pumping engine and a compensating
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensating cylinders, having a constant connection
with the force main, to permit the gradual passage of water between the air
chamber and force main, and a normally closed valve permitting the escape of fluid
from the air chamber, when opened, and controlled by the pressures in the force
main and air chamber, the pressure in the force main tending to close the valve,
substantially as described.
4. The combination with the force main of a pumping engine, and a compensating
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensating cylinders, having a constant connection
with the force main, to permit the gradual passage of water between the air
chamber and force main, a valve permitting the escape of fluid from the air
chamber, when opened, and controlled by the pressures in the force main and
air chamber, the pressure in the force main tending to close the valve, and pressure
devices tending to close the valve, substantially as described.
5. The combination with the force main of a pumping engine, and compensation
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensation cylinders, having a constant connection
with the force main, to permit the gradual passage of water between the air
chamber and force main, a valve permitting the escape of fluid from the air
chamber, when opened, and controlled by the pressure in the force main and
air chamber, the pressure in the force main tending, to close the valve, and adjust-
able pressure devices also tending to close the valve, substantially as described.
6. The combination with the force main of a pumping engine, and a compensating
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensating cylinders, having a constant connection
with the force main, to permit the gradual passage of water between the air
chamber and force main, and a check valve between the force main and air
chamber, opening toward the force main, and normally closed, when the pressures
in the force main and air chamber are the same, substantially as described.
7. The combination with the force main of a pumping engine, and a compensating
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensating cylinders, having a constant connection
with the force main, to permit the gradual passage of water between the air
chamber and force main, a check valve between the force main and the air
chamber, opening toward the force main, and pressure devices tending to close the
valve, substantially as described.
8. The combination with the force main of a pumping engine, and a compensating
cylinder or cylinders deriving pressure from the force main, of an air chamber
between the force main and compensating cylinders, having a constant connection
with the force main, to permit the gradual passage of water between the air
chamber and force main, a check valve between the force main and air chamber,
opening toward the force main, and adjustable pressure devices tending to close the
valve, substantially as described.
9. The combination with the force main of a pumping engine, of an air chamber
having a constant connection with said main, to allow the gradual passage of water,
and a check valve controlling a larger connection between the main and air chamber,
and opening toward the main, substantially as described.
10. The combination with the force main of a pumping engine, of an air chamber
on said main, having an escape for the air independent of the escape of all the
water in the air chamber, and a valve controlling said escapes, and closed by the

page_text: pressure in the force main against an opposing pressure, whereby the escape is
opened upon a fall of pressure in the force main, substantially as described.
11. The combination with force main D, of an air chamber having a constant
connection with said main, to allow the gradual passage of water, pipe O extending
into the air chamber from the main, and normally closed check valve 3 closing said
pipe, and opening toward the main, substantially as described.
12. The combination with force main D, of an air chamber having a constant
connection with said main, to allow the gradual passage of water, pipe O extending
into the air chamber from the force main, and having openings 1 inside the air
chamber, and normally closed check valve 3, closing said pipe, and opening toward
the main, substantially as described.
13. The combination with force main D, of an air chamber having a constant
connection with said main, to allow the gradual passage of water, pipe O extending
into the air chamber from the force main, and having openings inside the air
chamber, normally closed check valve 3 closing said pipe, and opening toward the
main, and means for adjusting the closing tension upon said valve, substantially as
described.
Qantab 1002
NEWTON & SON,
Agents for the Applicant.