DOUBLE ACTING PUMP
Year: 1885

page_text: I, HENRY DAVEY, of Headingley Leeds in the County of York, Engineer, do
hereby declare the nature of my invention for "DOUBLE ACTING PUMP" 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 a construction of double acting pump arranged in such a
manner as to simplify the valves, and to give ready access to the wearing parts as
I will describe referring to the accompanying drawings, which are vertical sections
of pumps according to my invention, illustrating several modifications arranged to
suit various conditions of position and working. In all cases I employ two pump
barrels or cylinders, each fitted with a bucket or piston having a passage through it
covered by a valve opening in the direction of flow, and the suction inlet to the
pump is so arranged that there is always liquid ready for starting the pump into
action without the necessity for the charging with liquid which is required in
many pumps.
Throughout the several figures of the drawings the same letters are as far as
possible employed to indicate corresponding parts. Referring first to Fig. 1,
A and B are the two barrels, the buckets of which, being worked from opposite
revolving cranks or from opposite ends of an oscillating beam, are always moving
in opposite directions, that is to say when the bucket of A is ascending, the bucket
of B is descending and conversely. The suction pipe C opens into a suction air
vessel D with its mouth considerably above the bottom of D so that there is always
retained in the vessel sufficient liquid to charge the first barrel A when the pump
is started into action. The second barrel B which on starting is primed from A,
discharges into an air vessel E from near the bottom of which the delivery pipe F
ascends. The buckets and their valves are readily accessible on removing the .
covers a and b of the two barrels.
The action of the pump may be thus described. As the bucket of A nscends it
draws in liquid below it and discharges liquid through the bucket of B which is
descending. As the bucket of B ascends it draws liquid through the bucket of A
which is then descending and discharges the liquid above itself into the air vessel E.
Thus, in each complete double stroke there is a discharge equivalent to the capacity
of the two barrels. Fig. 2 shews a pump arranged to act as above described but
made in a compact form suitable for confined situations as for instance to serve as

page_text: a ships' pump. In this case access is got to the buckets and valves through lateral
doors a and b which may be screwed into their places with screw threads made in
segments as they are often used for the breech blocks of ordnance, so that part of
a turn serves to screw or unscrew them. Fig. 3 shews a pump of the same kind
but with the barrels A and B extended to a sufficient height to bring their
covers a and b with their stuffing boxes above the level of the water in a deep
well. In this case the upper parts of the barrels constitute the discharge air vessel,
the upper part of A being separated from the actual pump barrel by a partition G
which is a conical plug that can be drawn up with the bucket.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
.
The construction of double acting pump with two barrels, each fitted with a
bucket and its valve opening in the direction of flow, and with the suction arranged
so as to provide a supply of liquid to the pump at starting, substantially as described
and illustrated by the drawings.