IMPROVEMENTS IN STEAM PUMPS
Year: 1874

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane,
in the County of Middlesex, Patent Agent, for the Invention of
"IMPROVEMENTS IN STEAM PUMPS." -À communication from abroad
by William Atkinson, of Gardner, in the County of Grundy, and
State of Illinois, United States of América:
Sealed the 11th September 1874, and dated the 22nd July 1874.
5
COMPLETE SPECIFICATION filed by the said Alexander Melville Clark
at the Office of the Commissioners of Patents, with his Petition
and Declaration, on the 22nd July 1874, pursuant to the 9th
Section of the Patent Law Amendment Act, 1852..
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
MELVILLE CLARK, of 53, Chancery Lane, in the County of Middlesex,
Patent Agent, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS
IN STEAM PUMPS," and have petitioned Her Majesty to grant unto me,
O my executors, administrators, and assigns, Her Royal Letters Patent

page_text: for the same, and have made solemn Declaration that it has been
communicated to me from abroad by William Atkinson, of Gardner,
in the County of Grundy, and State of Illinois, United States of
America.
:
NOW KNOW YE, that I, the said Alexander Melville Clark, do 5
hereby declare that the following Complete Specification, under my
hand and seal, fully describes and ascertains the nature of the said In-
vention, and in what manner the same is to be performed, in and by
the following statement, reference being had to the accompanying Sheet
of Drawings, and to the letters and figures marked thereon (that 1
is to say) :-
This Invention relates to means whereby greater simplicity, less
liability to stoppage, and greater economy in the operation of pumps
may be secured. These means will first be fully described in connection
with all that is necessary to a full understanding thereof, and then 1
pointed out in the claim.
In the accompanying Drawing Figure 1 is a longitudinal vertical
*section of the steam pump; Figure 2 a horizontal section; and Figure 3
a detail view in section of the end of steam chest.
A represents the main cylinder of a pump having inlet ports a, a, 2
exhaust a³, and piston B; O is the piston rod which is extended through
the cylinder at each end and into the oppositely placed auxiliary
cylinders D, D'. These have respectively water inlet d, outlet d³, and
pistons E, E¹, the latter being reciprocated at the same time and by the
same power as the main piston B; F is the steam chest in which is 2
placed the valve operating pistons G, G, having the steam inlets g, g,
and connected by stem H having the medium disc or flange h; I is the
main valve recessed to receive the flange h. by which it is moved back
and forth by the movement of pistons G, G;. J, J; are channels
leading from the steam space behind pistons G, G, to the exhaust; 3
K, K, are valves having shanks k operated by a lever L that is pivoted
at 1, and actuated by a sliding bolt M; the latter are alternately moved
by the piston B in its reciprocations. -
:
The operation of the pump is as follows:-As the piston E moves
forward and creates a vacuum behind it the water flows in through a
inlet d, follows the piston, and as soon as the latter begins to return

page_text: .
courses through the valve e, it now follows the channel N and the
piston E¹, which in its turn is moving forward and creating a vacuum in
its rear.
As soon as the piston E¹ begins to move back this same water
passes through valve e¹ and is on the next movement expelled through
outlet d'. This produces a continuous flow of water at the exit,
effect which has been produced heretofore, but I believe by different
means and a different mode of operation.
an
As the pistons G, G, are perforated at g, g, and receive the same
pressure of steam on each side it is necessary to destroy this equilibrium
in order to make the pistons move. This: I do by sliding forward the
two valves K. alternately and thus letting the steam escape through a
channel J', Figure 3, to a space behind the valve and thence to the
exhaust through channel J.
As upon the degree of freedom with which the steam is exhausted
from behind the valve K depends the resistance to valve piston's G, and
the consequent velocity and power exerted by the piston B, I use the
transverse screw or valve O, Figure 2, that works across the channel
way J, and may be made to graduate the size of outlet for the steam.
This enables me to use a large piston and yet regulate the degree of
power exerted, while it also allows me when using water that is muddy,
or from other causes inclined to foam, to destroy this tendency by
enlarging the exhaust outlet.
It will be observed that the valves K and the valve pistons G with
their several seats are all arranged in the steam chest and maintained in
place by a single cap P which may be held only by two set screws. The
caps P have a recess or chamber p behind the piston K which com-
municates with steam channel ways J, J. This is very important as
these parts require frequent examination and adjustment to cause them
to fit closely and operate in the most effective manner. By arranging
them all together in the ends of the chest F complete access to them is
obtained in a moment, while even in the Cameron pump, which is the
nearest approximation to mine, and esteemed the most convenient of
access, it requires a longer time to take out and return these parts than
to refit them.
Having described the nature of the Invention, and the manner in
which the same is to be performed, I declare that what I claim as new
Dalt in

page_text: 1st. The combination with main cylinder A, having steam ports a, a²,
and the rod C having thereon a middle piston B and two end pistons E,
e, E, e, of the two cylinders D, D', placed at opposite ends of main
cylinder, having respectively water inlet d-and outlet d³, and connected
by a channel way N, as and for the purpose specified.
2ndly. The combination with piston G of valves K and valve scat
caps P, the latter arranged in the ends of the chest and having
channels J, J, arranged as and for the purpose specified.
In witness whereof, I, the said Alexander Melville Clark, have
hereunto set my hand and seal, this Twenty-second day of July,
in the year of our Lord One thousand eight hundred and
seventy-four.
Witness,
HY. SWALES,.
53, Chancery Lane,
London.
A. M. CLARK. (L.S.)