Improvements in Pumps and Pumping Engines.
Year: 1892

page_text: Date of Application, 18th Aug., 1892-Accepted, 24th Sept., 18921
COMPLETE SPECIFICATION.
Improvements in Pumps and Pumping Engines.
I, GEORGE THOMAS HYDE of 4, Moorfields, Fore Street, London, E.C.,
Patent Agent, do hereby declare the nature of this invention (a communication
to me from abroad by Julius Maemecke of Berlin, Kingdom of Prussia, German
Empire, Merchant,) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
My invention relates to improvements in pumps, and consists firstly in a novel
construction of steam-pumps," whereby the condenser of the steam-engine working
the pump is dispensed with. My invention consists secondly, in a particular
operation of the valves, the opening of the suction-valves and of the delivery-
valves being effected in a compulsory manner by means of cranks and cams, or
equivalent mechanisms, and occurring before the change of the stroke, whereas the
closure of the corresponding delivery-valves or suction-valves may be effected by
means of springs, weights, water-pressure or any other means having a continuous
action, and occurs simultaneously with the opening of the valves, or nearly so.
My invention will be more readily understood by reference to the accompanying
drawings, in which:
Fig. 1 is an elevation of my improved pump, partly in section,
Fig. 2 a plan of the same,
Fig. 3 is a sectional elevation of the suction-valve and delivery-valve, and means
for opening and closing the same.
Fig. 4 is a similar sectional elevation of an air-suction-valve.
Fig. 5 is an elevation showing the part of the pump containing the delivery-
section-, and air-suction valves.
of my
Fig. 6 illustrates a steam-pump embodying the second part
Fig. 7 is another form of construction to the same effect.
Similar letters refer to similar parts throughout the several views.
invention.
In the form of construction illustrated by Figs. 1 to 5, I employ a special air-
suction-valve, in conjunction with an upward extension of the pump-tube, into
which sucked-in water enters from below, and the steam to be condensed from
above. In its general features, the pump is constructed substantially as described
in my Patent No. 5340" and I will only give a short explanation of the
different parts. A is the body of the double-acting pump, and B the plunger
working therein. F and S are the delivery- and suction-valves respectively, kept
on their seats by springs G G' encircling their stems. These valves are operated
by means of cams, as shown at I, Fig. 3, mounted on a shaft which is rotated
directly by the steam-engine. Cam operates on roll R secured on lever L
pivoted at P. To this lever L the connecting-rod J is linked at J¹, and
operates at its upper end a double-armed lever L', adapted to raise the
delivery-valve F. Another cam on the same shaft as I, depresses the roll R³ on
the connecting-rod J, pivotted at P' to a short lever mounted on the pivot P.
The lower end of the connecting-rod J' is linked to a double-armed lever L',
adapted to raise the suction-valve Š.
The pump-tube X is continued upwards laterally of the pump and forms a
condenser C in its upper portion, the suction-water entering from below, as
already mentioned, and the steam to be condensed from above, through a bent
pipe Ď reaching down into the condenser C. The water coming from the
pump-tube and that proceeding from the condensation of steam leave the con-
denser and enter the body of the pump by the suction-valve. The air liberated
by the condensation of steam accumulates in the upper part of the condenser C
round the pipe D. This air must be removed, as otherwise it would gradually.
Price 81

page_text: fill the whole condenser; therefore special air-pipes E have been provided.
through which the air is caused to pass into the body of the pump at the
beginning of the stroke.
An air-sucking valve Y is inserted between pipes E
and the pump-chamber. This valve Y is opened in a compulsory manner, like
the main suction- and forcing-valves, but may be closed by a spring, a weight
or any equivalent means.
The valves are operated in the following manner: At the beginning of the
suction-period, the air-suction valve Y is first opened by means presently to be
described. Thus the air is drawn off from the condenser C into the pump-
chamber, the main suction-valve being of course closed during that time. The
valve is kept open during about of the complete course of the plunger, i.e.
during about of the stroke. Then valve Y is closed, and at the same time the
suction-valve opened, so that the suction-water and the condensed steam are drawn
into the pump-chamber. A short time before the end of the stroke the suction-
valve is closed, and the delivery-valve opened. Now the pressure in front of the
plunger increases and is maintained during the whole delivery-period, i.e. during
the next stroke of the plunger. Hereafter the air-suction valve Y is opened again
and the operation of the valves begins anew as described.
The period during which air is drawn into the pump-chamber is very short, as
the air, having at first a pressure of 1 of an atmosphere, is gradually compressed,
towards the end of the stroke, to a very small fractional amount of its original
volume; this is effected by the pressure of the column of water contained in the
condenser and by that of the water drawn into the pump-barrel. A notable part of
the air is also absorbed by the water in consequence of the increased pressure.
Owing to all these facts, the amount of water drawn in during the suction period
is but slightly less than if the suction valve were open during the whole stroke.
11
The pipe leading the exhaust-steam to the condenser C may be located more than
32 feet above the level of the water to be raised, so that the entrance of water.
into the steam-cylinder is utterly impossible. In steam-pumps with condensers as
usually constructed this is a very sensible inconvenience, and it is only possible to
overcome it by employing at least 32 feet of pipe. In my improved steam-pump,
the height of suction is to be deducted from the said 32 feet, so that only a con-
siderably shorter pipe is required.
The
"As all the valves are operated directly by the engine, and not by the vis viva of
liquid or the pressure of the air, the opening of the valves is effected very easily
and the height of suction may be increased in a very important measure.
condenser may be arranged in such a manner, that a most complete vacuum is
obtained independently of changes in the level of the water to be raised. The
condenser forms in itself the suction air-chamber of the pump, thus a special air-
chamber is dispensable.
The greatest advantage of the improved arrangement of the condenser resides
however in the. omission of all other devices hitherto necessary for effecting the
condensation of steam, such as the air-pump, the reciprocating valve, the pipe for
injecting cold water, the overflow-pipe, the fittings; also, the exhaust steam pipe is
shortened.
The pump is started by expelling the air by means of an air-ejector. It is not
necessary to increase the dimensions of the pump on account of the fact that air is
sucked in during a fraction of the suction period, as this is of very little importance
and the quantity raised by the pump is almost the same as that yielded by an
ordinary pump of equal dimensions. Supposing for instance the height of suction
to be 16 feet 6 inches, and the proportion of air contained in water to be ✓ of the
volume of the latter at a pressure of 16 of an atmosphere (this is rather too much
than too little,) the volume of air is about To of the whole amount sucked in,
without taking the absorption into account.
If the driving steam-engine has a distributing valve-motion, the main shaft of
the engine is extended to the pump and employed for operating all the valves by
means of cams or eccentrics. The cam-disc c operates on the lever 1, pivotted at 1,

page_text: provided with a roll r, and linked to the connecting-rod t, which depresses the
right end of the double-armed lever d and thus raises the air-suction valve Y,
whereas this valve is closed by the pressure of spring as soon as the contact
between roll and the cam or cam-disc c ceases, that is to say, after the plunger has
accomplished about of its complete course. It is immaterial in what manner
the air-suction valve Y, and the valves in general, are lifted, and this may also be
effected by means of eccentrics.
If the engine has a slide-valve distributing, motion, all the valves of the pump
would be operated by means of bell-cranks e, as shown in Fig. 1, those acting on
each two superposed valves being connected by connecting-rods g. The bell-cranks
themselves are operated by a connecting-rod coming from the steam-engine, as
shown at T. The air-suction valve is operated by means of a nose N on the bell-
crank of the left suction-valve, said nose striking against a connecting-rod o and
operating a lever h. When the nose N is out of contact with connecting-rod o, a
spring pretracts the latter into its original position. The time the valve is opened
may be easily adjusted by means of a displaceable stop. It will be noticed that
the valve is closed suddenly, whereas it is closed gradually when operated by a
cam-disc. This does not however impair the efficiency of the pump, as the air-
suction valve is very small. This valve may also be constructed as a slide-valve,
or a cock may be substituted for the same.
The air-suction valve must be located at the top of the pump, as this is the
first place where air is gathered at the change of the stroke; moreover, this air
may be forced into the delivery-chamber at the beginning of the delivery period,
in order to replace the air absorbed at the increased pressure. If a small quantity
of steam has followed the air, it will be condensed very rapidly in the pump-
chamber.
I will now describe the second part of my invention, i.e. the novel valve-motion
consisting in opening the delivery- and suction-valves in a compulsory manner,
before the change of the stroke, by the accurately timed action of suitable
mechanisms, whereas the closure of the corresponding suction- and delivery-valves
is effected simultaneously, or nearly so, by the aid of continuously acting means,
such as springs, weights, or pressure of liquid.
This second part of my invention may be applied to pumps of all kinds, single-
and double-acting, and not merely to double-acting steam-puinps.
In Figs. 6 & 7 I have shown two different double-acting pumps embodying this
part of my invention. The action of the valves is in each case timed in such a
manner that one of the suction-valves is closed, and the corresponding delivery-
valve opened at the end of the suction period, before the change of stroke, whereas
at the end of the delivery period, and likewise before the change of the stroke, the
delivery-valve is closed, and the corresponding suction-valve opened.
In Figs. 6 I have shown the construction of the pump as it would be employed
when driving the pump by a common exhaust steam engine or by the high-pressure
part of a compound steam-engine. In both cases a slide-valve distributing motion
is employed. The main slide-valve of the engine is operated by means of an
eccentric e having a small lead-angle -20° to 30°-(see the diagram on the left
of Fig. 6). The slide-valve rod a is continued beyond the slide-valve chest, and
linked at a to the connecting-rod b which operates the bell-crank e, adapted to
raise the suction-valve I by means of a cam, in the same manner as described with
reference to Figs. 1 & 2. The suction-valve II, and the delivery-valves III and IV,
are likewise operated by cams, bell-cranks e, and connecting-rods g. The change
of stroke occurs when the eccentric e' reaches the positions indicated by 62 and 2
on the diagram. The eccentric e¹ being at a and, that is to say, at a suitable
interval before the change of the stroke, said interval being measured by the
angle 8, the suction-valve on the suction-side is closed, and the delivery-valve on
the same side opened, whereas the delivery-valve on the delivery side is closed, and
the suction-valve on the same side opened.

page_text: +
The effect of this valve-motion is the following: When the suction-valve II in
..the rear part of the pump is closed shortly before the end of the suction period, and
the delivery-valve IV in the same part of the pump opened, the entire pressure
of the raised water acts on the rear end of the plunger; at the front end of the
same the pressure of the water is completely removed, as the suction-valve I has
been opened, and the delivery-valve III closed. At the same time steam is
admitted into the cylinder, and it will be obvious that the steam will be at full
pressure at the change of stroke, and the plunger will at the same time be subjected
to the full water-pressure. Thus all shocks will be avoided, and the calculation of
the dimensions of the driving-gear need only be based on the difference between the
steam-pressure and the water-pressure, whereas hitherto the calculation had to be
based on the sum of these two pressures.
In Fig. 7 I have also illustrated the construction of the pump when driven by a
condensing-engine or by the low-pressure side of a compound engine. In this case
I employ a considerable lead (40° to 50°) for the eccentric e¹ operating the dis-
tributing slide-valve. The main-connecting-rod for operating the valves of the
pump, imparts an oscillating motion to the disc Q of a Corliss-gear, and thus the
required valve-motion is obtained.
The valve-motion may be obtained by any other suitable means, for instance by
means of cam-discs or eccentrics on a continuous shaft, or by means of a connecting
rod located below the slide-valve chest, as shown in dotted lines in Figs. 6 & 7.
The action of the valves is the same as before described, irrespectively of the
particular kind of the pump, whether the same is a single-acting, a double-acting,
or a differential pump. The result attained is the same as already described; in a
single-acting pump, however, the strain to which the driving gear is subjected,
depends on the full steam-pressure, and not on the difference between that pressure
and the water-pressure, as stated with reference to double-acting pumps. Never-
theless, the strain is still inferior to that occurring in pumps of usual construction,
where the strains are calculated for a pressure equal to the sum of the steam- and
water-pressure. In a differential pump the effect will be the same as in a double-
acting pump.
My improved valve-motion somewhat reduces the volumetrical efficiency of the
pump. i.e. the quantity of water delivered at each stroke of the plunger; the
mechanical effect is however considerably increased, i.e. the same motive power will
raise a greater quantity of water in the same time than an ordinary pump.
In order to avoid shocks occasioned by the eis viva of the water, the suction-valve
on the delivery-side of a double-acting pump may be opened a short time before
closing the delivery valve, and the delivery-valve on the suction-side a short time
before the closure of the suction-valve.
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:-
:-
1. A steam-pump having a condenser communicating with the pump tube or
forming a part of the same, a pipe for leading the exhaust steam of the steam-
engine into the said condenser, another pipe for leading air from the condenser into
the pump-chamber, and an air-suction valve inserted into the air-pipe; the motion
of this valve being timed in such a manner, that it is opened for a short while at
the beginning of the suction period, the main suction-valve of the pump remaining
closed during that time and opening simultaneously with the closure of the air-
suction valve, substantially as described, and for the purpose set forth.
2. A pump having the motion of its valves timed in such a manner that the
suction-valve is opened by a suitable gear before the end of the delivery period,
and the delivery-valve before that of the suction period; the corresponding delivery-
and suction-valves being closed simultaneously or nearly so, substantially, as
described, and for the purposes set forth.
J

page_text: 3. As a particular means for compulsorily opening the valves of a pump, the
oscillating Corliss-gear disc Q, and connecting-rods, levers and cams for operating
the valves, substantially as shown in Fig. 7 of the accompanying drawings and
described with reference thereto, for the purpose set forth.
Dated this 18th day of August 1892.
GEORGE THOMAS HYDE,
By Geo. Thos. Hyde,
4, Moorfields, Fore Street, London, E.C., Agent for the Applicant.