IMPROVEMENTS IN PUMPS AND IN PUMPING
Year: 1856

page_text: PROVISIONAL SPECIFICATION left by Richard Archibald Brooman nt
the Office of the Commissioners of Patents, with his Petition, on the
2nd December 1856.-A communication.
I, RICHARD ARCHIBALD BROOMAN, of 166, Fleet Street, in the City of
London, Patent Agent, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN PUMPS AND IN PUMPING," communicated to me by a
foreigner residing abroad, to be as follows:-
This improvement in pumping is a method of preserving the momentum
which has been once imparted to the column of water in the act of raising it,
whereby a steady or nearly steady stream will be delivered, while the durability
of the several parts is much increased, since the strains consequent upon the
slamming of the valves are entirely avoided. It consists in the employment
of three or more separate buckets in one pump, which are made to act upon
the column of water in such manner that one of the buckets shall be com-
mencing to lift just as one is ceasing to do so, and in so commencing shall take
the water at precisely the speed at which it was moving as the other
was about leaving it. To operate in this manner, the buckets are each worked
in a separate short cylinder, the first of which is extended into the water;
the second is set to the side of that upon the delivery pipe; and the third
in like manner upon the delivery pipe of the second, its own delivery pipe
being carried up to the height to which the water is to be raised. Each
of the pump chambers is covered, its piston rod working through a stuffing
box, and each piston having valves opening upward. These pistons have alter-
nate motion, being attached to three cranks upon a shaft placed over the pump

page_text: chambers, the cranks being spaced at regular distance apart. If, now, the
bucket of the lower chamber be at the lowest point of its stroke and just about
to commence its ascent, that in the next above it will be just passing out of
its greatest speed, in consequence of the position of its crank, but will still be
lifting, the water rushing through the bucket of the first, then acting as a foot
valve. The bucket of tho third chamber will have accomplished a part of its
descent, for its crank will then have made one-third of the semi-revolution,
which constitutes a full down stroke. Now, when the crank of the first bas
made a like third from its lowest point the crank of the second will be within
that distance of its own highest, and consequently the pistons of the first and
second will at that precise moment be moving at uniform speed. From the
positions of the cranks, however, the speed of the first is accelerated as the
work goes on, and that of the second becomes retarded; the valves of the first,
therefore, close gently at the moment of unison, and those of the second begin
to open to allow the water raised by the first (now become the lifting bucket)
to pass through it. While this is occurring, the bucket in the third chamber
is descending through the asconding column to become in its turn the lifter,
when its crank shall have passed one-sixth of the revolution beyond the lowest
point. The water is thus taken by one bucket at precisely the speed at which
the preceding one was leaving it, whereby there is no slamming of the valves,
and the momentum of the rising column is not lost. The arrangement of four
or more chambers with buckets worked from cranks set at equal angles to
each other would give more nearly an approximation to a regular and uniform
flow at the delivery pipe, there being then a bucket oftener at its maximum
speed.