IMPROVEMENTS IN SAFETY VALVES FOR THE BOILERS OF KITCHEN RANGES AND OTHER BOILERS OF HOT-WATER APPARATUS."
Year: 1881

page_text: LETTERS PATENT to John David Adams, of Marshall Street, in the County
of Middlesex, for an Invention of "IMPROVEMENTS IN SAFETY VALVES FOR
THE BOILERS OF KITCHEN RANGES AND OTHER BOILERS OF HOT-WATER
APPARATUS."
PROVISIONAL SPECIFICATION left by the said John David Adams at the
Office of the Commissioners of Patents on the 16th February 1881.
JOHN DAVID ADAMS, of Marshall Street, in the County of Middlesex.
"IMPROVEMENTS IN SAFETY VALVES FOR THE BOILERS OF KITCHEN RANGES
AND OTHER BOILERS OF HOT-WATER APPARATUS."
This Invention has for its object improvements in safety valves for the boilers of
kitchen ranges and other boilers of hot water apparatus.
The improved safety valve comprises a cup like vessel, which is connected with
the boiler in any convenient manner, so that the water from the boiler has free
access to the cup at the lower part. The mouth of the cup is partly closed by a
screwed cover or lid. There is a circular opening in the lid and from it a tube
descends within the cup nearly to the bottom. The opening in the lid of the cup
is covered by an hemispherical or conical valve, from which is suspended a frame
loaded with weights sufficient to keep the valve closed against the hydrostatic
pressure within the boiler. The frame is of cylindrical form; it has a flange at
the lower end to support the weights, which are annular. This loaded frame
surrounds the cup like vessel, which serves as a guide, permitting the valve to rise
but preventing it from being displaced. In the operation of the apparatus, although
the valve will open sufficiently soon to, avoid danger if from a stoppage in the
pipes the apparatus should be exposed to steam pressure, nevertheless the valve
will not open when the ordinary drawing off cock attached to any portion of the
pipes in connection with the boiler is closed, as the shock resulting from the sudden
closing of the cock will be taken up by the air, which will always be contained in
the cup like vessel mentioned above, and will act as a spring in the space around
the tube dipping down into the cup, as already described.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John David Adams in the Great Seal Patent Office on the 16th
August 1881.
JOHN DAVID ADAMS, of Marshall Street, in the County of Middlesex.
"IMPROVEMENTS IN SAFETY VALVES FOR THE BOILERS OF KITCHEN RANGES
AND OTHER BOILERS OF HOT WATER APPARATUS."
This Invention has for its object improvements in safety valves for the boilers of
kitchen ranges and other boilers of hot water apparatus.
The improved safety valve comprises a cup like vessel, which is connected with
the boiler in any convenient manner, so that the water from the boiler has free
access to the cup at the lower part. The mouth of the cup is partly closed by a
screwed cover or lid. There is a circular opening in the lid and from it a tube
descends within the cup nearly to the bottom. The opening in the lid of the cup
is covered by an hemispherical or conical valve, from which is suspended a frame
loaded with weights sufficient to keep the valve closed against the hydrostatic
pressure within the boiler. The frame is of cylindrical form; it has a flange at
the lower end to support the weights, which are annular. This loaded frame
surrounds the cup like vessel, which serves as a guide permitting the valve to rise
but preventing it from being displaced. In the operation of the apparatus, although
the valve will open sufficiently soon to avoid danger if from a stoppage in the
pipes the apparatus should be exposed to steam pressure, nevertheless the valve
will not open when the ordinary drawing off cock attached to any portion of the
pipes in connection with the boiler is closed, as the shock resulting from the sudden
closing of the cock will be taken up by the air, which will always be contained in
the cup like vessel mentioned above and will act as a spring in the space around
the tube dipping down into the cup, as already described.
In the Drawing hereunto annexed I have shewn a safety valve constructed
according to my Invention. Figure 1 is a vertical section, and Figure 2 a side
elevation of the valve.
A is the lower part of the vessel formed at the bottom in such a manner that it
may be secured to the boiler; B is the upper part or cover of the vessel; C is a
tube descending from the top of the cover nearly to the bottom of the vessel. The
cover B is also shaped so as to form an upward prolongation of this tube. The top
of this tubular extension is closed by the valve D, from which hangs a frame E
that has a flange E¹ projecting outwards from it all around its lower end; F are
the annular weights carried by the frame E; G is a disc, shown separately at
Figure 3, which is interposed between the inlet to the vessel A and the lower end
of the tube C; this disc serves to direct outwards into the air vessel any water
which may rise up through the inlet and prevent it from passing directly into the
tube C.
Having thus described the nature of my Invention, and the manner of
performing the same, I would have it understood that I do not make any claim to
the sole use of a dead weight safety valve for boilers of hot water apparatus, but
I claim the construction of such safety valves with an air vessel, substantially as
herein before described, to prevent escape of water at the valve at the times when
any of the draw off cocks in connection with the boiler are opened or closed.
In witness whereof, I, the said John David Adams, have hereunto set my
hand and seal, this Thirteenth day of August, in the year of our Lord
One thousand eight hundred and eighty one..
JOHN D. ADAMS. (L.S.)