Improvements in Safety-valves for Steam Boilers or Generators.
Year: 1899

page_text: Date of Application, 8th June, 1899
Complete Specification Left, 26th Jan., 1900-Accepted, 3rd Mar., 1900
PROVISIONAL SPECIFICATION.
Improvements in Safety-valves for Steam Boilers or Generators.
I, BENJAMIN RICHARD HERMAN, M.Inst.M.E., of McLeod Road, Karachi, in
the Province of Sind, in the Empire of India, Engineer, do hereby declare the
nature of this invention to be as follows:-
This invention relates to an improved safety-valve for steam boilers or
generators, and is especially suitable for use in connection with high-pressure
steam boilers or generators, the main object being to do away with the heavy
and dangerous springs as now used which have been increased in size and
strength from time to time as higher pressures have been brought into use.
According to my, invention, a steam conduit taking the form of a bifurcated
pipe, single at the end which is secured to the boiler and double or branched
into two at its reverse or upper end, is so arranged that steam can pass from
the boiler into it.
Each of the bifurcations from the main trunk extend out laterally at an angle
and their outer end is bent so as to come about parallel again with the main
trunk. The interior surface of these parallel ends is made nicely cylindrical
and in one is fitted a valve seat and in the other a piston. In the middle
between the two branch pipes is a bracket which supports at its upper end a
horizontal beam pivoted at its centre. At the extremities of this beam are
pivotally connected the valve-rod and the piston-rod of the valve and piston
above referred to. The said piston and valve are so arranged as to counter-
balance each other when there is no steam in the cylinder. The piston should
have a slightly larger area than that of the counterpoise valve, so that the piston
when there is steam in the boiler will exert sufficient pressure through the
medium of the connecting beam to keep the said 'valve on its seat.
The piston has holes through it and small governing valves are kept normally
pressed firmly on their seats at the upper or outer ends of these holes by means
of spiral springs encircling the valve spindles; the said springs being confined
at their upper ends by means of a cap or stop piece fixed on the piston rod.
These governing valves on the piston are so arranged and proportioned that
they will lift at a given pressure and by so doing reduce the effective area of
the piston to less than that of the counterpoise valve, the piston being then
overcome by the said valve, which latter is lifted off its seat by the steam
pressure and the steam escapes, as desired.
This safety-valve can be made direct-acting, or in any other form where the
principle is applied and is suitable as a high pressure valve for all purposes.
A valve constructed substantially as above described, although automatic in its
action is more under the control of the attendant and can be adjusted and
maintained to lift at any pressure.
Dated the 7th day of June 1899.
PHILLIPS & LEIGH,
Agents for the Applicant,

page_text: I, BENJAMIN RICHARD HERMAN, M.Inst.M.E., of McLeod Road, Karachi, in
the Province of Sind, in the Empire of India, 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:-
This invention relates to an improved safety-valve for steam boilers or
generators, and is especially suitable for use in connection with high-pressure
steam boilers or generators, the main object being to do away with the heavy
and dangerous springs as now used which have been increased in size and
strength from time to time as higher pressures have been brought into use.
I will now proceed to describe the invention with the aid of the accompanying
drawings, in which:
Figure 1 is a sectional-elevation of a safety-valve for a steam boiler constructed
according to my invention.
Figure 2 is a plan view corresponding to Figure 1.
According to my invention, the steam conduit takes the form of a bifurcated
pipe a, a, a, single at the end which is secured to the boiler and double or
branched into two members a¹, a² at its reverse or upper end This bifurcated
conduit is so arranged over the steam exit orifice that steam can pass from the
boiler into it in the direction indicated by the arrows in Figure 1.
Each of the bifurcations a¹, a² from the main trunk a extend out laterally
at an angle and their outer end is bent so as to come about parallel again with
the main trunk as shewn. The interior surface of these parallel ends is made
nicely cylindrical and in one is fitted a valve seat b and valve b, and in the
other a piston c. In the middle between the two branch pipes is a bracket d
which supports at its upper end a horizontal beam e pivoted at its centre on a
pin-bolt f, for example. At the extremities of this beam are pivotally connected
the valve-rod g and the piston-rod h of the valve 6 and piston e above referred to.
The said piston and valve are so arranged as to counterbalance each other when
there is no steam in the cylinder. The piston should have a slightly larger area
than that of the counterpoise valve, so that the piston c, when there is steam in
the boiler, will exert sufficient pressure through the medium of the connecting
beam e to keep the said valve on its seat.
The piston has holes through it and small governing valves are kept
normally pressed firmly on their seats at the upper or outer ends of these holes
by means of spiral springs k encircling the valve spindles: the said springs being
confined at their upper ends by means of a cap or stop piece fixed on the piston
rod. These governing valves on the piston e are so arranged and proportioned
that they will lift at a given pressure and by so doing reduce the effective area
of the piston to less than that of the counterpoise valve b1, the piston being
then overcome by the said valve, which latter is lifted off its seat by the steam
pressure and the steam escapes, as desired, say through a conduit such as m.
This safety-valve can be made direct-acting, or in any other form where the
principal is applied and is suitable as a high-pressure valve for all purposes.
A valve constructed substantially as above described is although automatic in
its action more under the control of the attendant and can be adjusted and
maintained to lift at any pressure.
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 a safety-valve for steam boilers or generators, the combination with the ♬

page_text: steam conduit of a safety valve of two lateral conduits leading therefrom, a
lift-valve fitted in the mouth of one of these lateral conduits and a piston in
the other, said valve and piston being adapted to normally counterbalance each
other, a beam connecting the rods of the said valve and piston, said beam being
supported so as to be capable of rocking holes through the piston and lift valves
normally held on their seats by springs adjusted to yield on a predetermined
steam pressure being attained, governing said holes and so unbalance the pressure
in the two lateral conduits by reducing the effective area of the piston imme-
diately blow-off pressure is attained, constructed and operating substantially as
described and illustrated.
2. The combination with a steam boiler or generator of a safety-valve con-
sisting of the combination with the steam conduit of a safety valve of two
lateral conduits leading therefrom, a lift valve fitted in the mouth of one of these
lateral conduits, and a piston in the other said valve and piston being adapted to
normally counterbalance cach other, a beam connecting the rods of the said valve
and piston, said beam being supported so as to be capable of rocking, holes
through the piston and lift valves normally held on their seats by springs adjusted
to yield on a predetermined steam pressure being attained, governing said holes
and so unbalance the pressure in the two lateral conduits by reducing the effective
area of the piston immediately blow-off. pressure is attained, constructed and
operating substantially as described and illustrated.
Dated this 26th day of January 1900-
PHILLIPS & LEIGH,
23, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.