Certain Improvements in Multiplex Plunger Pumps.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Certain Improvements in Multiplex Plunger Pumps.
I, GEORGE EDWIN Dow, residing at No. 114 Beale Street, in the city and county
of San Francisco, and State of California, one of the United States of America,
Manufacturer, 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 :-
"
My invention relates to the class of pumps which, having a number of plungers, are
generally known as "multiplex-plunger pumps." My invention consists in the novel
constructions and combinations of the several parts which include a casing or housing
subdivided into inter-communicating chambers, a series of single-acting plungers
driven from cranks upon the main shaft, valves in the plungers and the compartments
and other mechanism, all of which will be hereinafter fully described.
Referring to the accompanying drawings,
Figure 1 is a vertical section taken through the axis of one of the plungers,
and showing a diaphragm between the suction and crank-chambers.
Figure 2 is a similar section taken through the line x-x of Figure 3, showing
the suction and crank-chambers in one.
Figure 3 is a longitudinal vertical section taken through y-y of Figure 2.
Figure 4 is a horizontal section taken through ww of Figure 1.
Figure 5 is a horizontal section taken through z-z of Figure 1.
A are the plungers, which are here shown as acting vertically, though this is
not essential, as they may act horizontally or otherwise.
They are not less than three in number so as to maintain an even balance and
pressure.
These plungers are driven from cranks B, upon the crank-shaft C, which is
journaled in the lower part of the containing case, this case enclosing all the
operating parts of the pump. The cranks are set at equal distances apart upon
the circle which represents their throw, and have a uniform throw or stroke.
The plungers are connected with the cranks by connecting rods D, and by
means of a pulley E, upon the end of the shaft, or other well-known medium,
power is transmitted to drive it, and through it the plungers.
The plungers A are in the form of hollow cylindrical shells, accurately fitted in
casings or sleeves F, within which they reciprocate. These sleeves project from the
bottom of the valve-chambers G, into the lower part of the case H. which contains
and encloses the cranks and connecting rods.
In the upper part of each hollow piston is fitted an inlet-valve 1, opening
upwardly into the independent chambers G, and upon each side of the plungers
are similar valves J, opening upwardly from the casing H, into the valve-chambers G.
Above the chambers G, is a discharge-chamber K, having the delivery-valves L,
through which the water is delivered from the chambers G, into the chamber K,
and from this chamber it passes out through the discharge-opening or pipe at M.
In Figures 2, and 3, I have shown the inlet or supply-pipe N, opening directly
into the lower part of the casing H, in which the cranks are contained.
This construction will serve very well in pumping clear water, and for use in con-
nection with hydraulic elevators, and under other similar conditions.
The reciprocation of the hollow plungers A, forms a vacuum in the chambers G,
and the valves I, and J, will open, admitting water from the chamber H, through
these valves into the chambers G, and from these it is forced through the valves L
into the discharge-chamber K.

page_text: In cases where the water is dirty or acidulous, or is otherwise unfitted to come
in contact with the cranks and working parts, the chamber H is divided by a
horizontal diaphragm or partition O, as shown in Figure 1, into two parts H,
and H¹.
The inlet-opening N, connects with the upper chamber H', from which the
valves 1, and J, deliver into the chambers G, as above described.
In this case, the plungers A are made longer, and the lower portion of each passes
through a sleeve F in the diaphragm O, corresponding with the sleeve F at the bottom
of the valve-chamber, and a partition or diaphragm P, cuts off the lower part of the
piston or plunger from the upper part.
In this case, openings are made in the sides of the upper part of the plunger A,
as shown at Q, to admit water from the chamber H₁ into the piston, and thence to
the valve I.
In this construction, shown in Figure 1, it will be seen that the lower chamber H,
below diaphragm 0, forms a complete compartment for the shaft, cranks, and
connecting rods, which compartment is entirely separate from the suction-chamber H'.
This gives an opportunity for the most perfect lubrication of the working parts
contained in the chamber H, and this I effect by admitting oil and water to said
chamber to such a level that all the working joints are immersed in the lubricating
liquid. The connecting rods D, have their upper ends united with the hollow lower
ends of the plungers A, by wrist-pins, as shown at R.
In order to lubricate the bearings of the crank-shaft, I have made the shaft hollow,
with a passage extending through it, and with small holes opening from this passage
into the journal-bearings of the shaft.
A cup S, containing a lubricant is connected by a pipe T, with the end of the crank-
shaft, this pipe passing through a stuffing-box which is fitted to the end of the
journal-box, and so as to allow the crank-shaft to revolve while proper connection is
kept up.
Pressure to force the lubricant from the cup S, is derived from the discharge-
chamber of the pump through a pipe U.
The cranks and connecting rod journals may be lubricated in a similar manner, or
by means of the water itself, when the latter passes through the casing of the cranks
on its way to the pump-chamber.
As this pump is designed for a large range of duty, it is necessary to prevent jar
and pounding when run at a high rate of speed. This I effect by maintaining a
constant downward pressure against the crank and wrist-pin journals, by means of
the extensions V, from the plungers A, passing up through closely-fitted sleeves V₁,
into the upper or discharge-chamber.
The area of these extensions is such that the pressure exerted upon them by the
water in the upper or discharge-chamber K, is sufficient to maintain a constant
downward bearing upon the wrist-pins and crank-journals, and the plungers may
thus be run at a very high rate of speed without pounding or jar, and the wear on all
journals is self-adjusting.
When the arrangement of the pump is such that the extensions V of the plungers A,
cannot pass directly into the discharge-chamber, they may be passed into any suitable
chamber which is connected with the discharge-chamber, so that the pressure of water
in the discharge-chamber will be exerted upon them to produce the same result as if
they entered directly into said chamber.
The number of plungers operating in connection with one suction-chamber and one
discharge-chamber, with separate valve-chambers intermediate between the two, and
each having valves operated by its own piston, insures a steady flow, and a steady
constant resistance to the rotation of the shaft, and enables me to obtain a large range
of rotative speed.
It will be manifest that various modifications of this arrangement of parts may be
made without departing from the invention. The valves in the plungers may be

page_text: omitted, and only stationary induction-valves used, or, in some cases, a single
induction-valve may be nsed in each plunger, and a single discharge-valve directly
above it, and when the speed is not great, the extensions may be omitted.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim, is-
1. A pump, having a case divided into suction and discharge-chambers, with
intervening or intermediate valve-chambers communicating with said suction and
discharge-chambers, and hollow reciprocating valved plungers mounted in sleeves
between the valve-chambers and suction-chamber, substantially as described.
2. A pump, having a closed case, the lower part of which forms a suction-chamber,
and in which the shaft, cranks, and connecting rods are contained, and the upper
part forms a discharge-chamber, while its intermediate or intervening part forms
independent valve-chambers communicating with the suction and discharge-chambers,
and hollow reciprocating plungers connected with the cranks and moving in sleeves
between the valve-chambers and the suction-chamber, said plungers having valves
through which water is admitted into the valve-chambers, substantially as described.
3. A pump, having a closed case divided into a chamber in its lower portion for
the crank-shaft, and connecting rods, wherein a body of lubricating fluid may be
maintained, and in which the cranks are immersed, a suction-chamber above the
crank-chamber, a discharge-chamber in its upper portion, and a valve-chamber or
chambers between and communicating with the suction and discharge-chambers, and
hollow valved plungers connected with the cranks and operating between the suction
and valve-chambers, substantially as described.
4. A pump, consisting of the casing divided into a crank-chamber, a suction-chamber,
a valve-chamber or chambers, and a discharge-chamber, in the order named, sleeves
extending between the valve-chambers and the suction-chamber, and between the
suction-chamber and the crank-chamber, and hollow valved plungers connected with
the cranks and operating in the sleeves, said plungers having openings in the suction-
chamber, substantially as described.
5. A pump, consisting of a casing divided into chambers for suction and discharge,
and intermediate valve-chambers, plungers operating between the suction and valve-
chambers, and connected by rods with cranks in the lower portion of the casing, and
extensions from the plungers extending into the discharge-chainber, or into a
chamber connected with said discharge-chamber, whereby pressure is applied
to maintain the constant downward pressure and contact between the cranks and the
wrist-pins of the connecting rods, substantially as described.
6. In a pump, the suction and discharge-chambers with intermediate and separate
valve-chambers, and three or more plungers corresponding in number to the
independent valve-chambers, cranks, and connecting rods, whereby the plungers are
reciprocated, and valves admitting water from the suction-chamber into the independent
valve-chambers, and passing it thence into the discharge-chamber, said plungers
having extensions projecting into the discharge-chamber, or into a chamber connected
therewith, whereby pressure is applied to maintain the constant downward pressure
and contact between the cranks and the wrist-pins of the connecting rods, substantially
as described.
7. In a pump, the casing divided into a chamber in its lower portion for containing
the crank-shaft and connecting rods, a suction-chamber above, a discharge-chamber
in its upper portion and intermediate separate valve-chambers between the suction
and discharge-chambers, hollow valved plungers connected with the cranks, and
operating in sleeves between the valve and suction-chambers, and extensions from said
plungers passing into the discharge-chamber above or into a chamber connected
therewith, substantially as described.
8. A pump, consisting of an exterior casing subdivided by partitions into a suction-
chamber which contains the cranks, a discharge-chamber, and intermediate and

page_text: independent valve-chambers, with induction and discharge-valves, single-acting
plungers reciprocating between the suction and each of the valve-chambers, a hollow
crank shaft, and cranks connected with the plungers, an oil-reservoir with a pipe
leading from it into the end of the hollow crank-shaft, and a pipe connecting it with
the discharge-chamber, substantially as described.
Dated this Fourteenth day of Tenu 1800.
For the Applicant,
W. E. GEDGE,
Agent.