Year: 1895

page_text: Pressure EnginUS.
1, HENRY DAVEY, of 3 Princes Street, Westminster, in the County of Middlesex,
Engineer 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 :-
My invention consists in improved means for increasing the efficiency of water
pressure machinery.
The means I employ are illustrated in Figs. 1 and 2.
Fig. 1 is that of a water pressure engine employed to actuate pumps having heavy
reciprocating parts such as well or shaft pumps actuated by means of pump rods.
a and bare motive power cylinders provided with admission and exhaust valves
Buch as described and illustrated in my Patent No. 4160% or any other suitable
form of valve. c is à plunger or piston connected to the pump by means of the
rod d, connecting rods e and quadrants q, q', and pump rods h, h². The said
plunger or piston is connected, directly or indirectly by means of a rod i to the
piston or plunger j working in a water cylinder k, having at the ends air vessels, 1, 1;
these air vessels 1, l, are partly filled with water so that when the piston or
plunger is moved in one direction or the other, the air above the water in one of
the air vessels is compressed whilst the air in the other is rarified.
In this way
when the piston or plunger is moving from one end of its stroke it is assisted by
the pressure of the air compressed in the air vessel at that end, and in moving from
mid position towards the other end its motion is retarded by the compression of
the air in the air vessel at the end towards which the piston is moving. Thus the
motion of the motive power piston or plunger c is assisted at the beginning of the
stroke, and retarded towards the end of the stroke, and in this way compensating for
the inertia of the pump rods and connections, and the inertia of the water.column
actuating the motive power piston or plunger c.
To minimize the loss of energy arising from shock in the motive power water
column caused by the fluctuations in velocity of the column, I employ a water
pressure cylinder and air vessel Fig. 2. p is the motive power water pipe, y a
plunger or piston working in a cylinder r, connected to the pipe p; attached to the
plunger 9 is a piston or plungers working in a cylinder t; from the cylinder t is a
pipe u connected to the air vessel v. Some water is placed in the air vessel v.
to is a plunger attached to the pistons and working in the cylinder, and y, y', are
valves in the chamber . Any leakage past the pistons passes into the cylinder,
and on the descent of the plunger w, the air and water present is forced out and
into the air vessel v, so that the latter is, by this means, kept charged.
The areas of the pistons 7 and s respectively are so proportioned, and the pressure
of the air in the air vessel v is so regulated that the pistons or plungers shall be
towards the bottom of their strokes when the pressure in the motive power pipe is
normal or below the normal; and the water in the pipe p is in motion. Should the
motion of the water in the pipe p be suddenly stopped, then the increased pressure
in the pipe p due to the inertia of the water would push out the pistons or
plungers 9 and, and thus force the water above the pistons into the air vessel v,
thereby compressing the air in the air vessel v. The energy thus stored in the air
vessel would be given out again to the water in the pipe p by the return of the
plunger when the pressure in the pipe p fell below the normal pressure.

page_text: A loaded relief valve of any suitable form is placed at 21, to prevent any excess
of pressure in the air vessel v.
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 :-
1st. The combination of the cylinder k, air vessel 1, or air vessels 1, 1, and the
piston, or plunger j, with a water pressure engine for the purpose substantially as
described and illustrated in Fig. 1.
2
2nd. The combination of the pistons or plungers 9 and s with the cylinders and t,
the air vessel v, and the water pipes p and u substantially as described and
illustrated in Fig. 2.
3rd. The combination of the apparatus claimed in the 1st claim, Fig. 1, with
that claimed in the 2nd claim,. Fig. 2 in any system of transmission or application
of power by water pressure.
Dated this 21st day of February 1895.
HENRY DAVEY.