Improvements in Means for Automatically Regulating the Feed Water Supply to Steam Boilers.
Year: 1895

page_text: Date of Application, 20th Sept., 1895
Complete Specification Left, 12th June, 1896-Accepted, 19th Sept., 1896
PROVISIONAL SPECIFICATION.
Improvements in Means for Automatically Regulating the Feed
Water Supply to Steam Boilers.
I, CARL GUSTAF PATRIK DE LAVAL of 16 Handtverkaregatan Stockholm,
Sweden, Doctor of Philosophy and Engineer do hereby declare the nature of this
invention to be as follows:-
The present invention refers to an apparatus, which is especially intended to
be employed in combination with water tube boilers of that kind which consists
of a single unbranched tube, in the one end of which water is fed in and from
the other end of which steam is delivered. In such water tube boilers it is
desirable to make the water supply dependent on the consumption of steam in
such a manner that in every space of time only as much water is fed into the
tube of the boiler as corresponds to the quantity of steam, required by the con-
sumption of steam during that same time. For this purpose the invention
consists in the employment of a throttling mechanism connected with the feed
water conduit and which as to its position is made dependent on the position of
that mechanism, which determines the consumption of steam, thus for instance
the speed governor of the motor. Said throttling mechanism may conveniently
be acted upon by a water pressure, the amount of which is regulated by said
speed governor. The throttling mechanism may be inserted in the pressure
conduit or in the suction conduit of the feed pump, or in branches from said
pressure or suction conduit. Supposing that the throttling mechanism be inserted
in a branch from the delivery pipe of the pump, the greatest quantity of water
is fed into the boiler, when the throttling mechanism is shut, and the boiler then
delivers its greatest amount of steam, whereby the greatest amount of power is
given off for which the motor in question is intended. According as this amount
of power is diminished the water pressure, acting upon the throttling mechanism,
is correspondingly altered by the governor of the motor, and the throttling
mechanism is thus opened, causing a part of the water in the delivery pipe of the
pump to pass through said throttling mechanism. The amount of water, delivered
by the pump to the boiler is thus reduced correspondingly.
If on the contrary the throttling device be inserted in the suction pipe of the
feed pump, the position of the throttling device is regulated by the governor of
the motor in such a manner, that the pump draws as great a quantity of water
and delivers it to the boiler, as is demanded by the want of power.
Dated this 20th day of September 1895.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Means for Automatically Regulating the Feed
Water Supply to Steam Boilers.
I, CARL GUSTAF PATRIK DE LAVAL, of 16A Handtverkaregatan, Stockholm,
Sweden, Doctor of Philosophy and 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 :-
The present invention refers to an apparatus which is especially intended for

page_text: being employed in combination with water-tube boilers of that type which consists
of a single unbranched tube, to one end of which water is supplied while from the
other end steam is delivered. In such water-tube boilers it is desirable to make
the water-supply dependent upon the amount of power, which may be required by
the varying loads of the motor or engine so that the quantity of water fed into the
tube of the boiler at any moment corresponds to the quantity of steam, required
by the load at the same moment. For this purpose the invention consists in the
employment of a device, which regulates the feed water supply to the boiler and
which is put in motion by means of the pressure of water, the amount of which
pressure is regulated by that organ, which determines the consumption of steam,
from the boiler such as for instance a speed governor of an engine driven by said
steam. The regulating device may either be located in the supply pipe of the feed
pump or in the suction pipe of the same or respectively in branches of said supply
and suction pipes. If located in a branch of the supply pipe all the water, which
the pump can deliver, is fed into the boiler when the regulating device is closed at
which moment the boiler delivers its greatest quantity of steam, whereby the
greatest amount of power is produced of which the motor is conveniently capable
of producing. According as this amount of power is diminished, the water
pressure by means of which the regulating device is put in motion is corre-
spondingly changed by the governor of the motor, causing it to open so as to
allow a part of the water supply from the pump to pass through said regulating
device, whereby the amount of water, delivered by the pump to the boiler is thus
correspondingly reduced.
On the contrary if located in the suction pipe the position of the regulating
device is controlled by the governor of the motor in such a manner, that the pump
can draw only as great a quantity of water and deliver it to the boiler, as is
demanded by the power to be generated by the engine.
For further explanation of my invention reference is made to the accompanying
drawings in which,
Figures 1 and 2 are respectively a vertical section and a horizontal section on
line 2-2. Figure 1, of my improved regulating device, showing its connection with
a branch of the supply pipe of the feed pump.
Figures 3 and 4 are respectively a vertical section and a plan partly in
horizontal section, showing the connection of the regulating device with the
cylinders of a double feed pump, for the purpose hereinafter described, and
Figure 5 is a vertical section of the regulating device, showing its connection
with the suction pipe of the feeding pump.
Similar letters of reference indicate corresponding parts.
A, Figure 1, represents the supply pipe leading from the pump to the boiler.
B is a branch pipe of the supply pipe A, with which branch pipe the regulating
device is connected. The outlet pipe D is arranged for placing the regulating
device in communication with the atmosphere or a suitable receptacle. M is a
pipe, leading water under pressure from any suitable source to the lower end of
the cylinder, the degree of that pressure being varied by the governor R of the
power generating motor or engine. For this purpose said governor can act for
instance by means of a lever fand connecting rod fl upon a cock F or another
analogous device, located in the outlet 1ipe E for said water from the cylinder.
The regulating device shown in Figures 1 and 2 further consists of a piston or
plunger C which is guided in the cylinder C, said piston being provided with two
transverse passages H, H', and a longitudinal bore G connecting said trans-
verse passages. In the intermediate position of the piston C₁ the transverse
passages H H approximately half close the branch-pipe B and the outlet pipe D
for the water respectively. L is a pipe, leading steam or water under corre-
sponding pressure to the upper part of the cylinder C. Said steam or water
pressure serves to balance the water pressure at the lower end of the cylinder C
approximately. In order to effect full balance according to the variations in the
water pressure at M and E a helical spring I is located below the lower end of the

page_text: ston C. In case the said water pressure is small, the desired balance may be
tablished only by means of the spring I, the steam pressure at the upper end of
e piston thus being omitted. Of course the spring I may also be located at the
pper end of the piston.
My improved regulating device acts as follows:-
f
With a normal load on the engine and a normal supply of steam, the piston C¹
ccupies the position shown in Figure 1. In this position of the piston, the supply
f water that passes from the pump through the supply pipe A to the boiler
orresponds to the quantity of water required by the same, while a portion of the
ater delivered by the pump is conducted through the passages of the regulating
When the load on the motor
evice and is discharged through the outlet-pipe D.
sincreased, the governor R partly closes the cock F, thus causing the water
pressure in the chamber at the lower end of the piston Ci to be increased, whereby
he piston C is moved upward, so as to throttle the communication between H¹
and B and H and D. A smaller quantity of water passes then through the passages
of the regulating device and the supply of feed water to the boiler through the
pipe A is correspondingly increased. On the contrary when the load on the
motor is diminished, the governor R partly opens the cock F thus causing the water
pressure in the chamber at the lower end of the piston C' to be diminished whereby
the piston C is moved in the opposite direction, so that the current through the
passages of the regulating device is increased, and the supply of feed water to the
Thus the boiler receives by
boiler in a corresponding degree diminished.
the employment of the apparatus described the proper amount of feed water
which corresponds to the varying load of the engine & consequently to the quantity
of steam required by the latter.
Figures and 4 shew in section and plan the connection of my improved
regulating device with a two cylinder pump, the cranks of which are located at
an angle of 45° towards each other. The arrangement shown is of advantage in
such cases in which the pump is intended for delivering water of a high pressure
and in which the passages H G H¹ of the regulating device are made small in
section. It may thus happen that dirt gathers in the said passages, thus stopping
them up. To avoid this inconvenience, the branch-pipe B is placed in com-
munication with the cylinder a of the pump, while the outlet pipe D is placed in
communication with the cylinder b. The quantity of water which passes through
the regulating device, is thus forced from one cylinder to the other, passing
through the passages H GH' in opposite directions at each rotation of the crank-
shaft of the pump. If dirt gathers in the passages during a stroke of the pump,
it is forced back again during the following stroke, and the passages are thus
kept clear. The regulating device is operated in other respects as before described
with reference to Figures 1 and 2 and like letters of reference indicate analogous
parts. No additional explanation is therefore necessary.
Figure 5 shews the connection of my improved regulating device with the
suction-pipe of the feed-pump. C indicates as above the cylinder for the piston C³,
B the suction pipe for the feed-water, D the suction outlet pipe to the pump,
5 H G H the passages in the piston, M the inlet pipe for water under pressure,
F the cock for regulating the amount of this pressure, R the governor of the
engine, La steam inlet, balancing the combined pressure of the spring 1 and of the
water from M.
30
The regulating device operates as follows: When the engine is working against
a normal load, the piston C¹ occupies its intermediate position, shutting off one
half of the passages B H¹ and HD. The pump then draws the feed water through
the suction pipe, B, and through the passages B H¹, G and H, D. By an increased
or diminished load on the engine, requiring a larger or smaller supply of steam, the
governor R acts upon the cock F so that the water-pressure on the lower end of
the piston C' is either diminished or increased so that the piston C' either moves
downwards, opening the passages B H¹, HD, or upwards throttling said passages.

page_text: Thus a greater or less quantity of feed-water is drawn by the pump and delivered
to the boiler.
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. In means for regulating automatically the feed water supply to steam boilers,
the combination of a regulating device, a pipe conducting water under pressure to
said regulating device, and means for regulating the amount of said water-pressure
according to the consumption of steam, substantially as and for the purpose set
forth.
2. In means for regulating automatically the feed water supply to steam boilers,
the combination of a regulating device, consisting of a movable piston, provided
with throttling passages, a cylinder for guiding said piston, a pipe conducting water
under pressure to one end of said piston, and means for regulating the amount of
said water pressure according to the consumption of steam, substantially as and for
the purpose set forth.
3. In means for regulating automatically the feed-water supply to steam-boilers
the combination of a regulating device, consisting of a piston provided with
throttling passages, a cylinder for guiding said piston, a pipe conducting water
under pressure to one end of said piston, a cock or similar throttling device
connected with said pipe and acted upon by the speed-governor of the motor,
substantially as and for the purpose set forth.
4. In means for regulating automatically the feed-water supply to steam boilers,
the combination of a regulating device, consisting of a piston, provided with throttling
passages, a cylinder for guiding said piston, a pipe conducting water under pressure
to one end of said piston, a spring, acting on said piston so as to balance said water
pressure, a cock or similar throttling device connected with said pipe and acted
upon by the speed-governor of the motor, substantially as and for the purpose set
forth.
5. In means for regulating automatically the feed-water supply to steam-boilers,
the combination of a regulating device, consisting of a piston, provided with
throttling passages, a cylinder for guiding said piston, a feed pump with two
cylinders, one of which communicates with the inlet and the other with the outlet
of the same, said throttling passages, a pipe conducting water under pressure to
one end of said piston, a spring acting on said piston so as to balance said water
pressure, a cock or similar throttling device connected with said pipe and acted
upon by the speed-governor of the motor, substantially as and for the purpose set
forth.
6. The construction of apparatus for automatically regulating the feed water
supply to steam boilers as shown on the drawings.
Dated this 12th day of June 1896.
JENSEN & SON,
77 Chancery Lane, London, W.C., Patent Agents.