IMPROVEMENTS IN STEAM PUMPS
Year: 1884

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I, GEORGE WEIR, of 49 Jamaica Street, Glasgow, in the County of Lanark,
North Britain, Engineer, do hereby declare the nature of my said invention for
IMPROVEMENTS IN STEAM PUMPS to be as follows:-
"
My said Invention has for its object to construct, combine, or arrange the parts
of a steam pump in an improved manner and especially so that it may act
satisfactorily when pumping water against a high pressure (as for example in
feeding steam boilers) and at the same time not be liable to work at too great
a speed when from any cause the pressure resisting it becomes reduced.
In carrying out the Invention an ordinary slide valve, or a pair of piston valves,
or other similarly-acting arrangement of valves, is applied to the steam cylinder
of the pump, and its motion is derived from a rotating crank driven from a small
special cylinder or engine or driven through gearing from large engines in con-
nection with which the steam pump may be used. The action of the rotating
crank is not transmitted directly to the valve, but through a differential lever
which is also connected to the piston rod of the cylinder and pump. The rotating
crank acting through a connecting rod on the differential lever causes it to move
the valve so as to admit steam to one end of the cylinder whilst the immediately
consequent movement of the piston and its rod makes the differential lever move
in such manner as would move back the valve were the crank motion discontinued
and thereby stop further access of the steam to the cylinder. It follows from this
arrangement that the motion of the steam piston must correspond in speed to that
of the rotating crank, and cannot become appreciably greater however the resistance
may be reduced. It also follows from the nature of the crank motion that however
great the speed of the piston may be at the middle of the stroke that speed must
be varied from and to a state of rest at the ends of the stroke in a gradual manner.
The crank which works the valve or valves may be driven by means of eccentric
wheels so as to obtain a more suitable motion; and when convenient two pumps
with their steam cylinders may be combined their valves being worked by one
rotating crank shaft.
The steam cylinder and pump are by preference arranged vertically the pump
being either single acting or double acting. When single acting the water is

page_text: admitted to the pump barrel at the top and the packing ring of the piston or
bucket is made free to move relatively to the body of the piston so as in its lowest
position to uncover passages through the piston which it covers in its highest
position. When the piston rises the packing ring being as it were left behind
a short distance uncovers the passages and allows the water to pass to the under-
side, but on the piston descending the packing ring remaining stationary for a
moment the passages become covered and the piston then forces the water through
the discharge valve.

page_text: COMPLETE SPECIFICATION.
"
I, GEORGE WEIR, of 49 Jamaica Street, Glasgow, in the County of Lanark,
North Britain, Engineer, do hereby declare the nature of my said invention for
IMPROVEMENTS IN "STEAM. PUMPS and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement that is to say :-
My said Invention has for its object to construct, combine, or arrange the parts
of a steam pump in an improved manner, and especially so that it may act
satisfactorily when pumping water against a high pressure (as for example in
feeding steam boilers) and at the same time not be liable to work at too great
a speed when from any cause the pressure resisting it becomes reduced.
One improvement consists in working the valve or valves of the steam cylinder
or cylinders of the pump by means of a rotating crank shaft the speed of which is
independent of the resistance of the pump, the action being transmitted to each
valve through a differential lever acted on by the piston rod in such a way as
to make the movement of the piston correspond with and not overrun that of
the valve.
A second improvement consists in a special arrangement of the pump and its
piston and bucket hereinafter particularly described.
A steam pump made with my improvements is represented on two sheets of
explanatory drawings which are hereunto appended. Figure, 1, on sheet 1 is a
front elevation; and figure, 2, on sheet, 2, is a vertical section, whilst figures, 3,
and, 4, are views showing the construction of the pump piston or bucket. In these
drawings the same reference numerals are used to mark the same or like parts,
wherever they are repeated.
My Invention is applicable to a steam pump with one steam cylinder and one
pump, but in the example delineated there are two steam cylinders, 5, and two
pump barrels, 6. The valves are worked by cranks, 7, on the ends of a shaft, 8,
which is made to rotate by means of a small steam cylinder, 9, arranged to drive a
crank shaft, 10, having formed on it a worm, 11, which gears with a worm wheel
on the shaft, 8. Each crank, 7, is connected by a link, 12, to a joint, 13, on a
differential lever, 14, one end, 15, of which is jointed to the valve rod, 16, the
other end, 17, being jointed to a block, 18, fixed upon the piston rod, 19. With
the parts in the position in which they are shown in figure, 2, it will be seen that if
the crank, 7, moves up or down it will shift the valve, 20, so as to admit steam to
the bottom or top of the cylinder, 5, and that the consequent movement of the
steam piston, 21, and its rod, 19, will through the differential lever, 14, tend to
move the valve, 20, back to its middle position, and consequently the steam will
continue to be admitted to the cylinder, 5, only if the crank, 7, by continuing its
motion neutralises the reverse tendency due to the movement of the piston, 21,
whilst if the piston tends to move faster than what corresponds to the motion of
the crank, 7, it will merely move the valve, 20, towards its middle position and
thereby diminish or cut off the supply of steam. Instead of the valve, 20, shown
a pair of piston valves or any equivalent arrangement of distribution valve may be

page_text: •
used; and the crank shaft, 8, may be driven by a small special engine as shown,
or through gearing from large engines in connection with which the steam pump
may be used, or in any other convenient way.
From the nature of the crank motion (of the shaft, 8,) it follows that however
great the speed of the piston, 21, may be at the middle of its stroke that speed
must be varied from and to a state of rest at the ends of the stroke in a gradual
manner. The crank shaft, 8, which works the valves may be driven by means of
eccentric wheels so as to obtain a more suitable motion if desired.
The steam cylinders, 5, and pumps, 6, are by preference arranged vertically as
shown, and the pumps may be either single-acting or double-acting. When single-
acting the water is admitted to the pump barrel, 6, at the top, and the packing
ring, 22, of the piston or bucket is made free to move relatively to the parts, 23, 24,
fixed on the rod, 19, so as in its lower position, in which it is shown in figures, 2,
and 4, the bucket being in section in the latter figure, to uncover passages through
the piston, which it covers in its highest position. As shown in the drawings the
packing ring, 22, is held between a flanged ring, 25, shown seperately in inverted
plan view in figure, 3, and a junk ring, 26, bolted to the flanged ring, 25, and
there is a free passage between the ring, 25, and the piston rod, 19.
The rings,
22, 25, 26, can move a limited distance between the disks 23, 24, fixed on the
rod, 19, and when this rod is rising the bottom disk, 24, is in contact with the
heads of the bolts which fix the junk ring, 26, to the flanged ring, 25, whilst the
top disk, 23, is at a little distance above the top of the flanged ring, 25. The
water above the bucket has consequently a free passage down through the flanged
ring, 25, and between the bolts to the underside of the bucket; but when the
rod, 19, descends, the top disk coming into contact with the top of the flanged
ring, 25, closes the passage through, and the bucket or piston forces the water
downwards, the discharge passage being provided with a check valve in the
usual way.
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
1-Working the valve or valves of the steam cylinder or cylinders of a steam
pump by means of an independent rotating crank shaft operating through a
differential lever or levers also acted on by the piston rod or rods substantially
in the manner and for the purposes hereinbefore described.
2-The combination of a vertical pump barrel arranged to receive the water at
its upper end and discharge it at its lower end, with a piston or bucket consisting
of a packing ring capable of moving between parts fixed on the piston rod so as to
open a through passage when rising and close it when descending substantially as
herein before described.
Date :
1 100%
EDMUND HUNT,
Applicant's Agent.