A Duplex or Combination Pump.
Year: 1894

page_text: Date of Application, 28th May, 1894
Complete Specification Left, 28th Mar., 1595-Accepted, 24th May, 1895
A Duplex or Combination Pump.
DAVID DAVIES Ironfounder Inkerman Foundry, Strand, Swansea, do hereby
declare the nature of this invention to be as follows:-
:-
This pump can be used for washing decks-as a double action force pump or as
a double action ships pump.
It has a double working barrel-a double valve box with four valves (called No. 1)
also another double valve box with two valves (called No. 2) one valve in each
box-under No. 2 a single down pipe to bilges leading into the double valve box
No. 1. In the double valve box No. 1 (underneath the lower valve) the suction
hose is connected and over head these two valves the discharge nozzles are placed.
When washing decks the connexion with bilge pipe is shut off by screwing up
two eyes in the lid of the single valve box No. 2 thus concentrating the whole
power on the force pump or for deck washing purposes.
The pump is erected all above the deck line and can be used by hand or steam
power.
Dated this 26th day of Man 100
I, DAVID DAVIES, of Inkerman Foundry, 11 Strand, Swansea, in the County of
Glamorgan, Ironfounder, 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 has for its object a duplex single-acting piston pump of such
design and construction as to render it particularly adaptable for use on board
ship as a combined bilge and force pump, and fire engine.
And in order that my invention may be more readily understood and carried into
practice I will now proceed to describe the same with reference to the accompanying
drawings of which Fig. 1 is a side elevation; Fig. 2 an end elevation; Fig. 3 a
plan, and Figs. 4 and 5 an end and side sectional elevation respectively, on lines ar.
and y-y Figs. 1 and 3, of a pump constructed according to my invention.
This pump has two vertical working cylinders a, a, each having sliding therein a
piston b, connected in the usual manner to, and operated by, two cranks formed.in
a common crank shaft r, so that they stand at an angle of 180° to one another and
consequently operate the pistons so that they always travel in opposite directions.
The lower end of each of these cylinders communicates through one of two
passages d (Fig. 5) with one of two valve boxes e, and these latter communicate
through openings governed by valves fand 9 respectively with common suction
and delivery chambers h, k. The delivery chamber k is provided with a single
outlet and the suction chamber h with two inlets m, m', one, m, of which com-
municates with the bilge pipe n and is governed by a valve o capable of being
[Price 8d 1
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page_text: secured on its seating by set screw p, whilst the other, m', which may be closed by
a loose cap g
is to allow of the necessary connection being made whereby the pump
may be used as a force pump.
A removable cover r, r, is provided in the top of the delivery chamber k to
facilitate the examination, repair, and cleaning of the valves fand 9, and this cover
is normally secured in position by set screws 8, s, screwing through bosses in a bart,
the ends of which slide through openings in uprights u, u, attached to the opposite
sides of the delivery chamber.
0,
A similar cover v is provided in the suction chamber above the valve and this
is secured in position by screws w, w, and has the set screw.p, which governs said
valve o, screwing through it.
When employing a pump constructed as above described for discharging bilge
water, the inlet m' is closed, and the valve o allowed free play.
The water, as one of the pistons ascends, is drawn into the suction chamber h
and from thence through one of the valves f, valve boxes e, and passages d, into
the cylinder in which said ascending piston works. At the same time the other
piston has been descending, so forcing the water, previously drawn into its cylinder,
out through one of the passages d into one of the valve boxes e, from whence it can
only escape through one of the valves g into delivery chamber k.
When converting the pump for use as a force pump, the valve o is secured in its
seating by screw p, so closing the inlet m, and the necessary suction pipe connected
to the inlet m', when the pump will operate in exactly the same manner as above
described.
The valves used throughout the pump are preferably of the ordinary winged
pattern, the projection from the top thereof being, in the case of the valves f and y,
increased in length to govern the lift as shown, whilst, to permit the valves f to
more readily fall to their seatings as the pistons descend, the passages d are carried
upwards so that they discharge into the valve boxes above said valves as shown
more clearly in Fig. 5.
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 duplex pump comprising two cylinders a two pistons b two ports or
passages d two valve boxes e two pairs of valves f and y and single suction and
delivery chambers and k arranged constructed and operating substantially as
described and illustrated in the accompanying drawings.
(2.) In a duplex pump the arrangement construction and combination of valves f
and g valve boxes e ports or passages d and suction and delivery chambers haud k
substantially as described and illustrated in the accompanying drawings.
(3.) In a duplex pump a suction chamber h having two inlets one of said inlets
being governed by a valve controlled by a set screw p and the other provided with
a loose cap y substantially as and for the purpose described and illustrated in the
accompanying drawings.
(4.) In a duplex pump a delivery chamber having a removable cover secured in
position by set screws s, s, bar t and uprights u substantially as described.
Dated this 28th day of March 1895.
CASTLE SMITH,
"Invention" Office, 54, Fleet Street, London, E.C.,
Agent for the Applicant.