An Improved Tap or Cock for Controlling Gas Supply Mains and Branches.
Year: 1898

page_text: Date of Application, 31st May, 1898
Complete Specification Left, 20th Jan., 1899-Accepted, 15th Apr., 1899
PROVISIONAL SPECIFICATION.
An Improved Tap or Cock for Controlling Gas Supply Mains and
Branches.
I, JOHN THOMAS GENT, residing at " Iviecliffe," Flushing, Falmouth, in the
County of Cornwall, Electrical Engineer, do hereby declare the nature of this
invention to be as follows;-
This invention is an improved tap or cock for use in connection with gas supply
mains or branches, it being of particular utility where gas is required to be turned
on and off frequently. The principal object of the said tap or cock's design is
to prevent any escape or leakage consequent upon wear, the said leakage being so
common to the ordinary gas tap or cock and so objectionable especially when
applied in connection with the use of acetylene gas.
The improved tap or cock according to this invention is formed with a liquid
cut off, (that is to say, the gas is freed and trapped by the displacement of a liquid
such as mercury) it being distinguished by a container into which the mercury is
placed and also to which is fitted an inlet and outlet gas supply and a plunger or
its equivalent, the said supplies being controlled or their communication established
and broken by the mercury being displaced in the container so as to trap the gas
between the terminations of the inlet and outlet pipes, the said displacement being
accomplished by a plunger or its equivalent which is actuated by hand or auto-
matic means. A device is fitted to the container to adjust the height of the liquid
in that part wherein the inlet and outlet gas supply pipes project.
In carrying the invention into effect in connection with one form of tap or
cock, the container, which is only of small dimensions, is divided up into three
compartments, but communication is established between them by the walls being
pierced or formed with a hole. The middle compartment is, preferably, the
larger one of the three, as it holds the body portion of the mercury, but it is only
a shallow receptacle and its open top is closed by an air-tight cap which seals the
mercury from the atmosphere and through which a plunger to be operated by hand,
or automatically, works for the displacement of the trapping liquid contained with-
in the shallow receptacle. Another compartment on the side of the shallow
receptacle holding the mercury in bulk constitutes a gas trapping chamber, into "
which the separated ends of the gas supply depend and within which the mercury
is made to rise and fall so as to free the said separated ends or cover them up
when the plunger, as aforesaid, is actuated to displace the mercury. The separated
ends of the gas supply, which constitute inlet and outlet bends into the gas-
trapping chamber, are fitted gas tight within the top of the said chamber, and
their extreme separated ends are chamfered off or inclined, in order to obtain a
gradual cut off of the gas when the mercury is displaced.
Disposed at a convenient point around the shallow chamber containing the
mercury in bulk is the third compartment, which is really a pocket within which
he mercury rises from the said shallow receptacle. This pocket is fitted with
n adjusting plug, preferably a screw, its purpose being to displace the mercury

page_text: In the said figs. the container a forming the body of the tap or cock, and which
is only of small dimensions, is divided up into three compartments a², a³, a², all
in communication by holes or piercings a, a, formed through the container's walls
which separate them. The middle compartment a³ is preferably the larger one,
and contains the larger body of the mercury, but it is nevertheless only a shallow
receptacle open at its top a, the said top being closed air-tight by a cap c which
seals the mercury from the atmosphere. Through this cap a plunger d works
for the displacement of the mercury contained in the receptacle a², the said plunger
being operated either automatically or by hand. The plunger in the drawing is
shown as a quick-threaded screw pin, d², having upon its inner end a fitte
head carrying a leather disc or diaphragm d, which latter, when the screw d² is
serewed down, acts upon the surface of the mercury in the receptacle a² and dis-
places it into the compartment a³; the said diaphragın also forming a means for
making good the joint between the cap e and the container a.
The compartment a is a gas trapping chamber into which the ends c, g, of the
gas supplies e, g², depend, and within which the mercury is made to rise and
fall, so as to establish and cut off communication between the said supplies, by
the action of the plunger d, the mercury rising within the said compartment
sufficient to cover up the end e of the gas supply e², or, if desired, the ends of both
gas supplies, although the covering up of the end e alone is accomplished in the
form of tap or cock shown in the drawings. The ends of the said supplies are
fitted gas-tight within the chamber a³ by an ordinary union joint h. The end e
of the gas supply e² is chamfered off or cut on an incline at e³, in order to obtain a
gradual cut off of the gas as the mercury rises to cover it.
The compartment a is disposed at any convenient point around the shallow
chamber containing the mercury in bulk, and is practically a pocket within
which the mercury rises from the compartment a². This pocket is fitted with
an adjustable plug i, preferably a screw, which can rise and fall, its purpose being
to displace the mercury within the said pocket and constitute a regulator to the
height to which the mercury shall be displaced within the trapping chamber a³
by the action of the plunger d. This regulator is of considerable importance
inasmuch as it obviates the necessity of any exact calculation as to the amount of
mercury required and also allows for any inaccuracies owing to the tap or cock
being at a slight inclination, although it is not absolutely necessary that such
regulator should be used.
It is to be understood that the ends c, g, of the gas supplies respectively discharge
and continue into and from the trapping chamber a³, the said discharging and
continuing being either broken or allowed by the rising,and falling of the mercury
in the trapping chamber, and the covering or freeing of the gas supplie's end.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
-
First. A gas cock or tap characterised by a container or receptacle holding
mercury and to which is fitted the open ends of a gas supply so as to discharge into
and continue from a part of the said container, and a plunger or its equivalent
fitted to the said container so as to be operated for displacing the mercury from
its normal level in the container to cover up the openings or the open end of a
gas supply for trapping the passage of the gas, substantially as described and set
forth.
Second. A gas cock or tap comprising in combination a container a having
within it three compartments a² a³ at in communication, and which hold mercury,
gas supplies e, g², connected to the said container so that their open ends extend
into the compartment a³, and a plunger d fitted to the compartment a³, substan-
tially as described and set forth.
Third. A gas tap or cock comprising in combination a container a formed into
three communicating compartments a², a³, a', which hold mercury, gas sup-