AN IMPROVED SAFETY VALVE FOR STEAM BOILERS OR OTHER VESSEL REQUIRING RELIEF FROM INTERNAL PRESSURE
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by Samuel Lees at the Office
of the Commissioners of Patents, with his Petition, on the 28th
September 1871.
I, SAMUEL LEES, of 24, Bradford Road, Huddersfield, in the County
of York, Engineer, do. hereby declare the nature of the said Invention
for "AN IMPROVED SAFETY VALVE FOR STEAM BOILERS OR OTHER VESSEL
REQUIRING RELIEF FROM INTERNAL PRESSURE," to be as follows:-
'
My Invention has for its object increased discharging or blowing-off
space, spaces or outlets acquired by a combination of opening surfaces
or circumferences so arranged as to require less weight in proportion
to the discharging surfaces before mentioned than any other valve now
in use for similar purposes, and is arranged in the following manner :-
:
Firstly. A brass seat consisting of from one to six distinct rings
inside each other, bearing a number of spaces or orifices between the
said rings, as shewn at A in Fig. 1 of the accompanying Drawings; the
rings or circles are held in their respective positions by a series of
radiated brackets verging from the centre to the outside, as shewn in
Figures 1 and 3 at B, the said brackets varying in number from two to

page_text: twelve, according to the size of the valve. The rings or circles may be
either cast on the brackets in one solid plate and the orifices cut in, or
cast separate and attached to the brackets by means of screws or rivets.
Secondly. A lid or cover to fit the same is made as follows:-A
circular plate the diameter of the larger orifices or space (Fig. 1 at D)
having from one to six semicircular or angular rings on the under side
of it (as shewn in Fig. 3 at C), which rings are turned exactly to fit or
fill the orifices or spaces (as shewn in Fig. 3) and ground in to a
perfectly uniform surface. Between the angular or semicircular rings
before mentioned a series of holes are drilled or cast (as shown in Fig. 2)
at E), so that when the lid is forced from its seating by the pressure
within the steam as four or more distinct discharging surfaces or outlets
to escape from, thereby rendering explosion through over pressure a
matter of impossibility.
This Invention can also be applied to pumps of different kinds, but
more especially to deep well or mine pumps, where a large quantity of
water is required to pass through the working valve or bucket, in either
of the following ways, viz., with the seat as before described, but in
place of the semicircular or angular rings of metal on the lid attach
thereto rings of leather cut of a proportionate size to cover the orifices in
the seat; or they may be made with cavities or recesses between the
orifices, such cavities or recesses to be filled with lead and faced or
turned true with the face of the seat, and in place of the semicircular
or angular rings on the lead before mentioned you make two rings upon
the lid for each cavity in the seat, which rings are made with a sharp
edge, so that being pressed on the lead before mentioned they make a
steam or water tight joint.
For safety valves they may be weighted either inside or outside by
lever, dead weight, or spring. This valve may be made to act in case
of deficiency of water by means of a float within the boiler, as shown
in Fig. 4.