Improvements in Safety Valves.
Year: 1893

page_text: Date of Application, 22nd Nov., 1893-Accepted, 3rd Feb., 1894
COMPLETE SPECIFICATION.
Improvements in Safety Valves.
I, JAMES BALDWIN, Engineer, of Devonshire Brass Works, Keighley, in the
County of York, 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 :-
My improved safety valve, has for its object, the assisting of an ordinary safety
valve, or a compound safety valve, so as to cause them to be quicker in their
action. By describing the drawings annexed hereto, I shall the more readily
make my improvement understood.
In Fig. 1, which gives a sectional elevation, I show an arrangement of two
safety valves A. and B, A being a dead weight, and B. a low water and high
pressure safety valve. From the top of the spindle shown C. I take a horizontal
lever pivoted at E, and at a given length, I place a valve F, shown in the drawing
as a ball-valve, with a flange G. running round, and fitting into a valve seat at
When the
the top of the branch H, which projects from the safety valve box I.
low water and high pressure valve B. lifts, the steam passes into the valve box J,
and up the branch K, lifting the ball valve L. (this valve being of a similar
construction to the ball valve F.) allowing the steam to escape, but in so doing it
lifts the dead weight valve A, and the steam then passes up the branch H. and
lifts the ball valve F, and assists to lift the low water and high pressure valve B,
making these valves lift very quickly, and so keeping a uniform pressure of steam
no matter how quickly it is generated.
In Fig. 2 I show a single low water and high pressure safety valve in section,
B. being the valve, K the branch, L. the ball valve, C. the spindle, E. the fulcrum
of lever, to the end of which is attached the ball valve L, so that when the
valve B. lifts, the steam rushes through the branch K, comes against the valve L,
and assists to lift the valve B.
Fig. 3 shows a section of a dead weight safety valve, the steam passing through
the valve B, into the chamber C, and through holes at E, and then coming
against the bottom of the dead weight, so assisting to lift the valve B.
Fig. 4 shows a dead weight M, or in place of this a spring or springs may be
used. When the valve N. lifts, owing to excessive pressure, the steam passes
into space O. and through the holes P. into the box Q, then through the branch R.
where it plays against the valve S, which has a lever attached to it pivoted at T,
this lever assisting to lift at U. the dead weight or spring M, so suddenly
releasing the pressure in the boiler, and bringing it down to its proper working
pressure.
Fig. 5 shows an outside view of Fig. 4 with the valve S. open.
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. The improved safety valves substantially as described
drawings.
and shown in
2. The use of a valve to assist in lifting the low water and high pressure
safety valves, utilising for such purpose the escaped steam from such valves.
3. The use of a valve to assist to lift a dead weight safety valve, utilising for
such purpose the escaped steam from such valve.
4. The use of a valve to assist to lift a spring safety valve, utilising for such
purpose the escaped steam from such valve.

page_text: 5. The utilisation of the escaped steam from a safety valve or valves, for the
purpose of assisting to lift such valve or valves.
Dated this 22nd day of November 1893.
JAMES BALDWIN,
Devonshire Brass Works, Keighley.