Improved Safety Gauge Cock for Steam Boilers with Signal Device for the Low-water Level.
Year: 1899

page_text: Date of Application, 24th Apr., 1899-Accepted, 10th June, 1899
COMPLETE
SPECIFICATION.
Improved Safety Gauge Cock for Steam Boilers with Signal Device
for the Low-water Level.
I, RICHARD SCHWARTZKOPFF, a subject of the Emperor of Germany, and
resident of No. 172A, Müllerstrasse, Berlin, in the Empire of Germany, Manu-
facturer, do hereby declare the nature of my said invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement:
-
The known or usual gauge cocks for steam boilers, in which a stopper of
easily fusible metallic alloy is used and after the melting of the latter by the
blowing off steam a whistle or other signal is operated, have the drawback, that
this melting of the stopper sometimes takes place even if the gauge cock is only
opened a little and the low-water level has not been reached. A frequent renewal
of the stopper is consequently necessary, which is inconvenient and expensive.
This unintended melting of the stopper before the low-water level has been
reached on the gauge-cock being opened is due to the fact, that the water of
the boiler, which fills the way or boring of the cock and in order not to cause
a melting of the stopper or plug, is sufficiently cooled by the external air surround-
ing the casing of the cock and by the radiation of heat on account of the metallic
parts, immediately passes out on opening the cock and is momentarily replaced
by the hot water of the boiler which, according to experience, suffices for melting
the stopper or plug.
According to the present invention, this drawback of the known gauge cocks
with easily fusible stoppers or plugs is avoided by providing the gauge cock
with two separate ways preferably lying over each other, of which only the one,
usually the narrower, is in communication with the casing of the signal device or
with the passage containing the stopper but not with the outlet of the cock,
whilst the other way of the cock allows of water being taken from the boiler
in the usual manner. The consequence of this construction is that on opening
the gauge cock, the cool water in contact with the stopper or plug is not renewed
every time the cock is opened and replaced by hot water from the boiler.
however, the water of the boiler drops to the lowest level, the upper way of the
cock also becomes empty and steam enters therein, which melts the stopper or
plug and operates the signal. This signal may consist of a whistle operated by
the melting of the stopper allowing the steam to pass to the whistle or it may be
an electric signal, for which the contact is established by the falling-off or fused
metal; the issuing steam can also suffice as signal, without a whistle being
provided.
The device can be applied to gauge cocks and valves.
Referring to the accompanying drawings
Fig. 1 is a vertical section through a gauge cock,
If
Figs. 2 and 3 are sections through different forms of the casing, bearing or
containing the box for the melting stopper.
a is the wall of the boiler, in which the cock is mounted in the known or
usual manner. The box or casing of the cock, as also the plug c, are each
provided with two ways or borings d, e and d', el respectively; the ways d and e
lead through the front wall of the casing b in order to enable a cleaning of the
ways from without and are closed or shut up by screw plugs f, g.

page_text: From the upper way e, a passage or channel i leading to the signalling device
branches off, such passage being preferably controlled by a cock j and a pipe k
communicating therewith, which is preferably enlarged at the top at and
receives the casing for the melting stopper or plug m. The pipe is either
smooth or plain (Fig. 1) or provided with transverse or longitudinal ribs
(Fig. 2, 3) for effecting a better cooling of the casing by the external air and
is, in any case, sufficiently long so as not to bring the melting stopper or plug
too near the hot cock casing b; an unintended or untimely melting of the stopper
or plug m is thereby avoided. The casing or box for the stopper or plug m is a
tubular body open at the top, in which the stopper or plug m is held by a
cap n.
The casing is suspended or screwed in the extension of the pipe k and
by constructing the casing as a pipe open at the top, the external cold air can
pass therein and cool it, so that an untimely melting of the stopper or plug is
prevented.
The hollow space of the pipe extension around the casing / has for its object
to catch air bubbles rising in the water, which otherwise might come in contact
with the melting stopper or plug and isolate it, so that the same would be with.
drawn from the direct action of the hot steam at low-water level and at least
a delay in the operation of the signal device could be caused. The lower end
of the casing bearing the melting stopper or plug is situated in such a manner
that the stopper m or its cap n almost shuts-off the pipe k, so that the ascending
bubbles of steam free from water must first come in contact with the stopper
and cause same to be melted. Air which has collected in the head ¹, can be
easily passed off by unscrewing the stopper casing 7 or by providing any other
suitable device for that purpose.
If on the low-water level not having reached the bottom edge of the way d, the
cock is opened, only the water in the way d and water from the boiler passes out,
whilst the water is retained in the way e. The unintended melting of the stopper
or plug m, each time the gauge cock is opened, is therefore no longer to be
feared. If however, the water-level in the boiler sinks below the low-water level,
the water also passes out of the way e of the cock and the steam of the boiler
enters such way, thus melting the stopper or plug m and operating the signal
device.
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 an improved safety gauge cock for steam boilers having easily fusible
stoppers, the melting of which operates a signalling device, the arrangement of a
separate way for the outlet of the boiler water in order to prevent the admission
of the hot boiler water to the stopper when opening the cock before the low-
water level is reached and the communication of the stopper casing with a second
way of the cock and cock casing through a pipe and channel substantially as and
for the purpose set forth.
2. In an improved safety gauge cock providing the pipe carrying the stopper
with transverse or longitudinal ribs, substantially as and for the purpose set
forth.
3/. In an improved safety gauge cock the arrangement of an open tube as
carrier for the stopper, such tube being detachably connected with the enlarged
head of the casing communicating with the separate way or boring in the cock
casing substantially as and for the purpose set forth.
PHILIP M. JUSTICE,
55, Chancery Lane, London, Associate Agent.