IMPROVEMENTS IN SAFETY VALVE APPARATUS
Year: 1876

page_text: LETTERS PATENT to John Charles Wilson, of Mona House, Westfield Park, in
the City of Bristol, Mechanical Engineer, for the Invention of "IMPROVEMENTS
IN SAFETY VALVE APPARATUS."
Sealed the 6th April 1877, and dated the 25th October 1876.
PROVISIONAL SPECIFICATION left by the said John Charles Wilson at the
Office of the Commissioners of Patents on the 25th October 1870.
JOHN CHARLES WILSON, of Mona House, Westfield Park, in the City of Bristol,
Mechanical Engineer. "IMPROVEMENTS IN SAFETY VALVE APPARATUS.'
These improvements have reference to the use of the safety valve, commonly
known as Klotz' safety valve, which consists of a cylindrical inverted cup lifted by
steam, which is let in from the boiler between the cup and a fixed piston. When
the valve is raised by the steam pressure the steam escapes under the piston and
between the rim of the cup and the valve seat.
According to my Invention two of these valves are placed together and covered
by a casing so that the steam which escapes may be let off through an escape pipe.
The valves are kept down by springs, which are placed outside this casing that they
may not be injured by the escape steam. The thrust from the springs is trans-
mitted through the covers of the casing by bridles or casings, having on the lower
ends spindles which rest on the valves. These bridles are at their upper ends
guided and prevented from tilting by bolts or other projections passing through
them. These bolts or other projections are screwed into or project from a balance
beam, with a fixed centre fulcrum on a standard from the valve casing. These
bolts may give the necessary compression to the springs which are inside the
bridles.
Or the springs may be entirely enclosed in casings, having on their lower ends
projecting spindles which pass through the valve casing to the valves, and are on
the upper ends guided by bolts or other projections from the balance beam, the
object of these spring casings being (as the bridles) to transmit the pressure of the
springs to the valves, and besides effectually to guard the springs, so that nothing
may be wedged in between their coils to increase their resistance. By this means
the valves will be truly lock-up valves.

page_text: Both the bridles or the bridle casings may be dispensed with, and the springs may
be arranged to bear direct on the valves at one end and on the balance beam at the
other, and a separate casing may be put round the springs to protect them, also
acting as funnels for the escape steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Charles Wilson in the Great Seal Patent Office on the 25th April
1877.
JOHN CHARLES WILSON, of Mona House, Westfield Park, in the City of Bristol,
Mechanical Engineer. "IMPROVEMENTS IN SAFETY VALVE APPARATUS.'
"
These improvements have reference to the use of the safety valve, commonly
known as Klotz' safety valve, which consists of a cylindrical inverted cup lifted by
steam, which is let in from the boiler between the cup and a fixed piston. When
the valve is raised by the steam pressure the steam escapes under the piston and
between the rim of the cup and the valve seat.
According to my Invention two of these valves are placed together and covered
by a casing, so that the steam which escapes may be let off through an escape pipe.
The valves are kept down by springs, which are placed outside this casing that they
may not be injured by the escape steam. The thrust from the springs is trans-
mitted through the covers of the casing by bridles, having on the lower ends
spindles which rest on the valves. These bridles are at their upper ends guided and
prevented from tilting by bolts or other projections passing through them. These
bolts or other projections are screwed into or project from a balance beam, with a
fixed centre fulcrum on a standard from the valve casing. These bolts may give the
necessary compression to the springs which are inside the bridles.
Or the springs may be entirely enclosed in casings, having on their lower ends
projecting spindles which pass through the valve casing to the valves, and are on
the upper ends guided by bolts or other projections from the balance beam, the
object of these spring casings being (as the bridles) to transmit the pressure of the
springs to the valves, and besides effectually to guard the springs, so that nothing
may be wedged in between their coils to increase their resistance. By this means
the valves will be truly lock-up valves.
Both the bridles or the bridle casings may be dispensed with, and the springs may
be arranged to bear direct on the valves at one end and on the balance beam at the
other, and a separate casing may be put round the springs to protect them, also
acting as funnels for the escape steam.
In order that my Invention may be fully understood and readily carried into
effect, I have shown in the Drawings hereunto annexed two arrangements of my
improved safety valve apparatus.
Figure 1 shows a vertical section, and Figure 2 a horizontal section of the safety
valve apparatus adapted for use with marine boilers.
A is a steam chamber forming part of or in communication with the steam
boiler. At the top of the chamber are two openings covered by inverted cup
valves B, B. C, C, are pistons fixed at a distance above the openings, and fitting
within the interior of the cup valves. Steam is admitted from the boiler to the
interior of the cup valves through the pipe D. When the pressure of steam is
sufficient to raise the valves, steam escapes through the space between the bottom of
the pistons and the valve seats, and enters a chamber E, from which it passes away
by the escape pipe F. G are the springs by which the valves are kept down on
their seats. The lower ends of the springs bear upon bridles H, from which descend
spindles I, which pass through the covers of the chamber E, and bear upon the top
of the valves. The upper ends of the springs bear against bolts J, carried by the
opposite arms of a balance beam K, turning on a fulcrum at L. The bolts J pass

page_text: through holes in the top of the bridles H, and serve as guides to prevent the bridles
from tilting.
In place of the springs being carried in bridles, they may be enclosed in casings,
as shewn at Figure 3, and these casings may have spindles descending from them to
pass through the covers of the chamber E, and bear upon the top of the valves. One
arm of the beam K is prolonged to serve as a hand lever, by raising or lowering
which steam may be caused to blow off at either valve.
Figure 3 shows a vertical section, and Figure 4 a horizontal section of the safety
valve apparatus adapted for use on a locomotive. In this arrangement the springs
are entirely enclosed in casings H, which take the place of the bridles in the
arrangement just described, and the chamber E and escape pipe F are dispensed
with. In other respects the valve apparatus is the same as that shewn at Figures 1
and 2.
Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I claim,—
First. The combined arrangement of safety valve apparatus, substantially as
herein-before described and illustrated at Figures 1 and 2.
Second. The combined arrangement of safety valve apparatus, substantially as
herein-before described and illustrated at Figures 3 and 4.
Third. Enclosing the springs of safety valves in a casing or bridle, the lower end
of which rests on the top of the valve, and through the upper end of which is a hole
through which passes the stud, against which the upper end of the spring bears, so
that the casing or bridle rises with the valve, as herein described.
In witness whereof, I, the said John Charles Wilson, have hereunto set my
hand and seal, this Twenty-fifth day of April, in the year of our Lord One
thousand eight hundred and seventy-seven.
A
A
JOHN C. WILSON. (L.S.)