Improvements in Self-acting Feed Regulating Apparatus for Steam Boilers.
Year: 1898

page_text: Improvements in Self-acting Feed Regulating Apparatus for
Steam Boilers.
We, HENRY MONCRIEFF STEELE, Chartered Accountant, 105, West George
Street, in the City of Glasgow, and JOHN ROBERT BIRD, Engineer, 10, Morrison
Street, in the City of Glasgow, do hereby declare the nature of this invention
to be as follows:-
This invention relates to self-acting feed regulating apparatus for steam boilers,
and it has for its object to provide simple and inexpensive apparatus by means of
which the admission of feed water is so controlled as to ensure that the desired
water level within the boiler may be constantly maintained.
The improved apparatus comprises an hydraulic cylinder attached to the upper
flange of the ordinary boiler check valve and a slide valve operated by a float
attached to the crown of the boiler, the cylinder and slide valve being so
arranged and connected that when the water in the boiler rises or falls above or
below a given level the boiler pressure is applied to actuate a piston in the
hydraulic cylinder, or is relieved therefrom, in order to hold down or relieve the
check valve.
Attached to the upper flange of the check valve is a stool, open at the sides
and supporting an hydraulic cylinder. A piston, made watertight by means of a
cap of vulcanized rubber or other suitable means has attached to it a piston rod
This
which passes through a gland formed in the bottom flange of the stool.
rod is of such length that when pressure is applied to the upper side of the
piston the rod presses on the check valve and holds it down on its seat. When
the pressure is released a spring placed between the bottom of the piston and a
support formed on the stool raises the piston till it comes into contact with a
screw passing through the top of the cylinder. This screw is fitted with a hand
wheel and is used to regulate the amount of lift of the check valve and to hold it
firmly down in its seat when it is necessary to shut off the feed water entirely.
A chamber is formed in the hydraulic cylinder above that portion traversed
by the piston so that water is always retained in the cylinder.
The apparatus regulating the supply of power to the hydraulic cylinder con-
sists of a slide valve casing attached to a sleeve passing through the crown of the
boiler. A bracket inside the boiler attached to the other end of the sleeve
carries a lever and float with a counter-balance weight. A spindle passing
through the sleeve connects a slide valve with the lever so that the valve is
moved up or down as the float rises or falls. A port in the slide valve casing
is connected by a tube with the upper end of the hydraulic cylinder, and a second
port in the casing is in communication with the atmosphere.
The action is as follows.-The slide valve is set so that when the float is
immersed about half its thickness in the water and the water is at normal level,
both the ports are closed. When the water rises above this level the float rises

page_text: also and opens the port allowing pressure to be exerted on the piston of the
hydraulic cylinder, and thus closing and holding down the check valve. When
the water falls below the normal level the float sinks with it and while shutting
off the pressure at the same time opens the exhaust port. This allows the spring
to raise the piston and permits the check valve to be raised by the feed water 5
in the usual way.
Improvements in Self-acting Feed Regulating Apparatus for
Steam Boilers.
We, HENRY MONCRIEFF STEELE, Chartered Accountant, 105, West George
Street, in the City of Glasgow, and JOIN ROBERT BIRD, Engineer, 10, Morrison
Street, in the City of Glasgow, 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:-
This invention relates to self-acting feed regulating apparatus for steam boilers,
and it has for its object to provide simple and inexpensive apparatus by means of
which the admission of feed water is so controlled as to ensure that the desired
water level within the boiler may be constantly maintained.
As shown by the accompanying drawing the improved apparatus comprises an
hydraulic cylinder A attached to a stool A¹ open at A' at the side and in turn
attached to the upper flange of the ordinary boiler check valve B and a slide
valve C operated by a float D attached to the crown E of the boiler the cylinder A
and slide valve C being so arranged and connected by a pipe C that when the
water in the boiler rises or falls above or below a given level the boiler pressure
is applied to act upon water, due to condensation of steam within said hydraulic
cylinder and pipe connection, and, thereby actuate a piston A2 in the cylinder A
or is relieved therefrom, in order to hold down or relieve the check valve B.
The piston A is made watertight by means of a cup A³ of vulcanized rubber
or other suitable substance and has attached to it a piston rod A' which passes
through a gland F formed in the bottom flange of the stool A¹. This rod A+ is
of such length that when pressure is applied to the upper side of the piston A³
the rod A presses on the check valve B and holds it down on its seat B¹. When
the pressure is relieved a spring G placed between the bottom of the piston A
and a support A5 formed on the stool A¹ raises the piston A³ till it comes into
contact with a screw H passing through the top of the cylinder A. This screw H
is fitted with a hand wheel H¹ and is used to regulate the amount of lift of the
check valve B and to hold it firmly down on its seat B¹ when it is necessary to
shut off the feed water entirely.
A chamber A is formed in the hydraulic cylinder A above that portion
traversed by the piston A³ so that water is always retained in the cylinder A.
The apparatus regulating the supply of power to the hydraulic cylinder A
consists of a slide valve casing C₁ attached to a sleeve C³ passing through the
crown of the boiler. A bracket I inside the boiler attached to the other end of
the sleeve C3 carries a lever J and float D with a counterbalance weight D'. A

page_text: spindle L passing through the sleeve C connects the slide valve C with the
lever J so that the valve C is moved up or down as the float D rises or falls.
A port C³ in the slide valve casing C¹ is connected by the tube C with the
upper end of the hydraulic cylinder A, and a second port C5 in the casing C¹ is
in communication with the atmosphere.
The action of the apparatus is as follows:-
The slide valve C is set so that when the float D is immersed about half its
depth in the water and the water in the boiler is.at normal level, both the
ports C3 and C5 are closed off from communication with the boiler pressure.
When the water rises above this level the float D rises also and opens the port C³
allowing steam pressure to be exerted on the water in the cylinder A which in
turn acts on the piston A3 of the hydraulic cylinder A thus closing and holding
down the check valve B. When the water falls below the normal level the
float D sinks with it and while shutting off the boiler pressure from the cylin-
der A and connection C at the same time opens the exhaust port C³ to the latter
connection. This allows the spring G to raise the piston A° and permits the
check valve B to be raised by the feed water in the usual way.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is:-
1. Feed regulating apparatus for steam boilers consisting of a slide valve
operated by a float and counterbalance weight in combination with a hydraulic
cylinder and piston adapted to control the supply of feed water to the boiler sub-
stantially as described.
2. Feed regulating apparatus for steam boilers consisting of a hydraulic cylin-
der having a piston actuated by the boiler pressure to press upon or relieve the
check valve in order to control the supply of feed water to the boiler, substan-
tially as described.
3. The arrangement of a slide valve operated by a float and counterbalance
weight within a steam boiler to control feed regulating apparatus, substantially
as described.
Dated this 4th day of November 1898.
WALLACE FAIRWEATHER,
Of the Firm of Cruikshank & Fairweather,
Chartered Patent Agents, 62, Saint Vincent Street, Glasgow,
Agent for the Applicants.