Improvements in and relating to Gas Valves or Stop Cocks.
Year: 1899

page_text: Date of Application, 28th Nov., 1899-Accepted, 30th Dec., 1899
COMPLETE SPECIFICATION.
Improvements in and relating to Gas Valves or Stop Cocks.
We, JAMES MURPHY, of 8, Suffolk Lane, Cannon Street, in the City of London,
Gas and Sanitary Engineer, and HENRY LEWIS ARNOLD, of 35, King Street,
Covent Garden, in the County of Middlesex, Solicitor, 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:-
This invention relates to a gas valve or stop cock constructed to act as on ordi-
nary stop cock, and provided with means for automatically cutting off the gas
supply in the event of a fire or an otherwise abnormal rise in the temperature in
the building where the device is fitted.
In the accompanying drawings Fig. 1 is an elevation and Figs 2 and 3 are
sectional elevations showing two different positions of the working parts. The
same parts are lettered to correspond in all three figures.
A is the valve casing and B the conical, valve ground thereinto and fitted with
a through way C in the ordinary manner. The valve B is made hollow and on its
upper end is screwed or otherwise detachably fitted an extension piece D having
a removeable cover E, a cavity or chamber F, a rod J passing through a central
aperture in the bottom plate d of the extension piece D and a conical tubular pro-
longation G. H is the automatic cut off or secondary valve made conical in the
form of a thimble and fitting the hollow interior of the main valve B its base h
fitting a corresponding seating 6 in the bottom of the hollow valve B. The rod J
is screwed or otherwise secured, preferably in a detachable manner, to the base h
of the secondary valve or thimble H and a spiral or other suitable spring K is
arranged so as to bear against the base hand against the under side of the plate d,
the tension of the spring being such as to press the thimble down into its lowest
position with the base on the seating b as shown in Figure 3.
The secondary valve or thimble H is held up against the pressure of the spring K
in the position shown in Figure 2 by means of a fusible plug L made of such
material or composition or alloy as to become fluid at an abnormal rise in tem-
perature, but preferably to become fluid at a considerably lower temperature than
that required to melt the lead or composition pipes carrying the gas supply or
other usual metal gas fittings. This plug holds the rod J by its head ; which may
be made detachable, or the rod itself is made detachable from the base h of the
thimble. The plug is provided with a central aperture just large enough to admit
the rod J but not large enough to allow the head j to pass through.
The device is made ready for use by detaching the cap E from the extension
piece D, removing the rod J threading the fusible plug L on the rod J and
screwing the latter into the base of the thimble H; or if the rod J should be
fixed to the base h, then the rod is drawn up through the plate d against the
pressure of the spring K, the head j is removed, the plug L threaded on the rod,
and the head j replaced on the upper end in the position shown in Fig. 2.
It will be now understood that the normal position of the thimble in the in-
terior of the conical valve is as shown in Fig. 2, which illustrates the full open
position of the stop cock, and that the device may be used as an ordinary stop

page_text: cock to shut off and open the gas supply. Should a fire occur or should the tem-
perature rise beyond the predetermined limit the plug L fuses and offering no
further support to the head of the rod J, the spring K comes into action and
shuts down the secondary valve or thimble H tightly against its seating 6 thus
effectually shutting off the supply through the way C of the main valve B.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is: -
(1) A gas valve or stop cock containing within its body a secondary valve held
up against the pressure of a spring by a fusible plug, substantially as described.
(2) A gas valve or stop cock, comprising a valve casing, a hollow conical valve
having a through way, an extension piece to said valve with a recess or cavity
therein, a rod passing through the bottom of said cavity and secured to a secon-
dary valve fitting the interior of the hollow conical valve, a spring arranged
between the secondary valve and the bottom plate of the cavity in the extension
piece and adapted to press said secondary valve down on its seating, said secon-
dary valve being normally held up away from its seating by a fusible plug sub-
stantially as and for the purpose herein described.
(3) A gas valve or stop cock having an automatic cut off secondary valve
arranged in combination therewith substantially in the manner and for the pur-
pose herein before set forth and illustrated in the accompanying drawings.
Dated this 28th day of November 1899.
F. W. GOLBY,
Patent Agent, 36, Chancery Lane, London, WC.,
Agent for the Applicants.
F. W. GOLBY,
Patent Agent, 36, Chancery Lane, London, W.C.,
Agent for the Applicants.