IMPROVEMENTS IN PUMPS
Year: 1884

page_text: 1, HERBERT JOHN ALLISON, of the firm of Allison Brothers, Patent Agents, of
Chancery Lane, in the County of Middlesex .do hereby declare the nature of the
invention for "IMPROVEMENTS IN PUMPS," and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:—
.
The invention is illustrated in the annexed drawings, in which Fig. 1. shows in
vertical sectional elevation a double-acting pump provided with the improvements
constituting my invention. Fig. 2. is a sectional plan view taken through the
upper half of the pump case and hollow piston. Fig. 3. is a vertical section taken
through a single-acting pump, and Figure 4. shows the same when the plunger has
completed its upward stroke. Figure 5. is a vertical section taken through the
lower portion of the pump-case showing the plunger barrel in position.
Similar letters of reference are used to indicate like parts throughout the several
figures.
A represents the pump-case, adapted for a double-acting pump constructed in
accordance with my invention. This pump-case
is made of equal diameter
throughout its entire length. At the lower end or upon the floor of this casing I
bolt the two cylinders K. K, open at their upper ends, and provided at their lower
ends with clack valves C. C, through which the water enters into the pump.
The cylinders or plunger barrels are made of a diameter considerably less than
that of the pump-case, and are made perfectly true upon their inner faces in order
to form a smooth guide-bearing for the plungers D, D, which reciprocate therein.
These plungers also carry or form the seat for the ball valves E. E, and are
attached by prongs or arms F. F, to the open ended hollow pistons G. G, which are
formed of sheet metal, cylindrical in form, and are made perfectly air-tight, and of
such a length that when the plunger is at the full length of its downward stroke
the top of the air-drum will be above the discharge-spout or top of the water
containing jacket A.
•
.
It should here be observed that the plunger barrels are perfectly circular in
cross-section and are separate, being surrounded by a water space or jacket B, by
which the strain or pressure from the body of water, contained within the pump-
case, upon the interior of the cylinders is greatly lessened and the danger of their
bursting is removed.

page_text: Midway of the height of the displacer is constructed a solid air-tight diaphragm I,
to which is pivoted the pitman or pump rod J, and by this means I am enabled to
obtain a free open space above the diaphragm, while the space below the diaphragm
forms an air-compression chamber, into which the water may partially enter upon
the downstroke of the piston, thereby compressing the air contained therein, so as
to produce a reaction or expansive effect of the air to assist in elevating the hollow
piston after the said downstroke has been completed, when the piston makes the
upstroke by cushioning upon the water within the pump chamber.
In the modification shown in Figures 3 and 4, the construction and mode of
operation are the same as above described, save that the water-jacket, instead
of being double, as shown in Figures 1. and 2, is made single and surrounds at
equal distance the floating piston.
I am aware that the piston-rod of a pump has heretofore been made of such size
that its downward stroke will displace about the same quantity of water that the
piston raises in its upward stroke, so that the flow of water from the pump will be
continuous, and so that the displacement of water by the enlarged piston-rod will
reduce the weight of water resting on the pump piston. Such enlarged piston-rods
or plungers have also been made hollow, so as to form an air-chamber. This,
however, I do not claim broadly.
-
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 combination of the pump-case A, and plunger barrel K, having clack
valve C, the open ended hollow piston G, of a length sufficient to extend above the
discharge spout when the plunger is at the full length of its downward stroke, the
air-tight diaphragın I, placed in said piston, the pitman-rod J, pivoted to the
diaphragm, and the plunger D, connected to the lower end of the piston by means
of arms F. F, the said plunger being provided with a ball valve E, substantially as
shown and described.
Dated thio First day of Februar 1984