IMPROVEMENTS IN APPARATUS FOR AUTOMATICALLY SHUTTING OFF THE SUPPLY OF GAS TO GAS BURNERS AND METERS
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Albert Aron at the Office of the
Commissioners of Patents on the 30th September 1881. A communication
from abroad by Arthur Silvain Fribourg, of Versailles, in the Republic of
France.
ALBERT ARON, of Rose Street, Newgate Street, in the City of London,
Warehouseman. "IMPROVEMENTS IN APPARATUS FOR AUTOMATICALLY SHUTTING
OFF THE SUPPLY OF GAS TO GAS BURNERS AND METERS." [A communication
from abroad by Arthur Silvain Fribourg, of Versailles, in the Republic of
France.]
It is well known that if a compound bar composed of two bars of unequally
expanding metals firmly secured together bo exposed to heat the compound bar
will curve or curl in the direction of the least expansible of the two metals.
In carrying out this Invention advantage is taken of this unequal expansion of
different inetals under the influence of heat to actuate the taps or cocks whereby
the supply of gas to gas burners or meters may be automatically shut off.
In applying this principle to gas burners the compound bar composed, say, of
iron and brass and bent into the form of an elongated horse shoe, is secured in a
vertical position by one end to the socket of the gas burner so that the gas flame
when lighted shall play upon it or heat it.
The free end of this compound bar is connected by a short cranked link rod with
a ring or washer mounted loosely on the plug or spindle of the tap. The face of
this ring is slotted for about one third of its circumference to receive a pin or
projection on a lever which is pivotted to the head of the plug or spindle. The
pin or projection on the lever is maintained in contact with the ring by a suitably
placed spring, and when the gas is turned off the pin or projection will be in the
slot of the ring.
To turn on the gas the lever is rocked to raise its projection out of the slot and is
then turned in the desired direction to open the supply channel to the burner. The
pin or projection will be maintained in contact with the plain face of the ring by the
spring. On the gas being lighted the heat of the flame will cause the compound

page_text: horse shoe shaped bar to open out or straighten by reason of the unequal expansion
of the metals of which it is composed. By this opening out of the horse shoe bar
the ring or washer with which it is connected will be rocked on its spindle. The
slot in the ring will thus be brought round to the projection on the lever which
will be caused by the spring to engage in the slot.
When the flame is extinguished either by turning off the gas at the meter or
accidentally the compound bar will rapidly cool and resume its normal form, in
doing which the ring or washer will be rocked on its spindle in the contrary
direction drawing round with it the lever, thus turning the tap and cutting off
the supply of gas to the burner.
The lever will be retained in this position by the slot, and thus the accidental
turning on and escape of gas and the consequent risk of explosion will be
avoided.
In applying the principle to gas meters whereby the turning off the gas supply
to the meter in case of fire may be effected, an arrangement of parts similar to
that above described may be employed. In this case however by a slight change
in the position of the link connecting the free end of the compound bar with the
ring or washer, the straightening out of the compound bar under the influence of
the heat of the fire would be made to turn off the gas supply tap.
Instead of compound bars compound plates may be used.
It will be evident that the mode of applying this principle of the expansion of
Compound bars-or-plates-under the influence of heat for the purpose above referred
to is capable of various and obvious modifications, the-arrangement of parts herein
-described being given as an example.