IMPROVEMENTS IN SAFETY GAS BURNERS
Year: 1873

page_text: LETTERS PATENT to Alfred Belt, of New Cross, in the County of
Kent, Gas Fitter, for the Invention of "IMPROVEMENTS IN SAFETY GAS
BURNERS."
Sealed the 14th April 1874, and dated the 18th October 1873.
PROVISIONAL SPECIFICATION left by the said Alfred Belt at the
Office of the Commissioners of Patents, with his Petition, on the
18th October 1873.
I, ALFRED BELT, of New Cross, in the County of Kent, Gas Fitter,
do hereby declare the nature of the said Invention for " IMPROVEMENTS IN
SAFETY Gas BurNERS," to be as follows;-
The object of my Invention is to automatically shut off the supply of
gas to the burner or nipple when the gas is put out, accidentally or
otherwise, and to effect this object I employ a valve between the gas
supply and the burner, which valve is operated by heated or expanded
atmospheric air or gas acting upon a metal diaphragm, which is placed
immediately below the valve. The heat necessary for the expansion of
the air I obtain from the lighted jet of gas at the burner acting upon a

page_text: chamber of air, which chamber of air communicates with the under side
of the metal diaphragm; this being raised by the expansion of the air
touches the bottom end of the valve, and raises it sufficiently to allow
the gas to reach the burner, the heat of which maintaining the chamber
of air in a rarefied or expanded state keeps the diaphragm up and the
valve open so long as the gas is burning. Upon the light at the burner
being blown or put out, accidentally or otherwise, the air in the chamber
cooling resumes its normal density, and allows the diaphragm to fall,
and with it the valve, thus closing the supply of gas to the burner, and
preventing the liability to explosions by escape of gas from the burner.
To light or relight the gas I apply for a few seconds a lighted taper
or other equivalent to the outside of the air chamber for the purpose of
heating the air and raising the valve as before described.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Belt in the Great Seal Patent Office on the
18th April 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
BELT, of New Cross, in the County of Kent, Gas Fitter, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of October, in the year
of our Lord One thousand eight hundred and seventy-three, in the thirty-.
seventh year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Alfred Belt, Her special licence that I, the
said Alfred Belt, my executors, administrators, and assigns, or such
others as I, the said Alfred Belt, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and at
all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN SAFETY GAS BURNERS," upon the condition (amongst
others) that I, the said Alfred Belt, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands and
seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause

page_text: the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alfred Belt, 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 thereof, reference being had to the Drawing here-
unto annexed, that is to say:-
This Invention consists in the automatically shutting off the supply.
of gas to the burner or nipple when the gas is put out, accidentally or
otherwise, and to effect this object I employ a valve between the gas
supply and the burner, which valve is operated by heated or expanded
atmospheric air or gas acting upon a metal diaphragm, which is placed
immediately below the valve. The heat necessary for the expansion of
the air I obtain from the lighted jet of gas at the burner acting upon a
chamber of air, which chamber of air communicates with the under side
of the metal diaphragm; this being raised by the expansion of the air
touches the bottom of the valve, and raises it sufficiently to allow the
gas to reach the burner, the heat of which maintaining the.chamber of
air in a rarefied or expanded state keeps the diaphragm up and the valve
open so long as the gas is burning. Upon the light at the burner being
blown or put out, accidentally or otherwise, the air in the chamber
cooling resumes its normal density, and allows the diaphragm to fall, and.
with it the valve, thus closing the supply of gas to the burner, and
preventing the liability to explosions by escape of gas from the burner.
To light or relight the gas I apply for a few seconds a lighted taper
or other equivalent to the outside of the air chamber for the purpose of
heating the air and raising the valve, as before described.
Fig. 1 of the annexed Drawing shews a section of the apparatus in its
most common form, with the valve V down on its seat, and the supply
of gas to the nipple or burner N consequently shut off. A is the air
chamber, which in the absence of any heat from the lighted gas at the
nipple or mechanically applied to the external part of the apparatus by
a lighted taper or other equivalent is of the same temperature, and
consequently of the same density or pressure as the external atmosphere.
D is the diaphragm, which I may make of gold, silver, platina, copper,
or any other metal or amalgam of two or more metals rolled into a thin
plate, which I make of a "dished" form, to give it the power of rising.

page_text: or falling under pressure, and which I fix by soldering or other means
to the lower part of the case C, the upper part of the case O¹ being
screwed or otherwise fixed to the lower part so as to make it air or gas
tight. This case I may make of brass, copper, iron, or any other metal
or mixture of metals. P is a hole drilled from the upper side of the
diaphragm through the body of the case O to the lower part of same,
through which the gas passes to the upper side of the diaphragm. I
may use one, two, three, or more of these holes, or gas passages; aș
occasion may require. S is a small screw for the admission of
atmospheric air or gas at its normal density to the air chamber A, 1
after the diaphragm is soldered or otherwise fixed on, this screw being
"screwed" tightly into its place, so to render the air chamber air
tight.
•
Fig. 2 shews a similar section of the apparatus, but with the gas
burning, and the air in the chamber A consequently expanded by the 1
heat conducted from the burner N; the diaphragm D up and the
valve V lifted by the diaphragm from its seat, allowing sufficient space
for the gas to flow through the passage or passages P to the nipple or
burner N. It will thus be seen that so long as the heat from the light
is maintained the air in the chamber A will be so expanded as to keep.
the valve open, and that when the light is blown or otherwise put out
the air in the chamber cooling to the temperature of the external air
allows the valve to fall and shut off the supply of gas from the
burner.
Having thus fully described my Invention, and the action of the
same, I desire it to be known that I do not confine myself to the precise
details I have described, and that I may vary the form of the apparatus
from that shewn in the Drawing, and may alter the same to suit the
different requirements of gas lighting without deviating from the
principles of my Invention, and I may vary the capacity of the air 3
chamber A so as to require a longer or a shorter time for the valve to
open and close by the variation in the temperature of the air in the said
chamber, but what I claim as my Invention is,―
First. The application of a diaphragm of metal of a "dished" form
for the purpose of lifting a valve by the expansion of the air under the 3
diaphragm.
☐ Second. The use of a valve of the "ball" form or type, which I claim
as my application to safety gas burners, though I do not confine myself

page_text: to the use of this form of valve, as in conjunction with the aforesaid
"dished" diaphragm of metal I may use a valve of the " spindle,"
"disc," or "
wing " form.
In witness whereof, I, the said Alfred Belt, have hereunto set my
hand and seal, this Sixteenth day of April, in the year of our Lord
One thousand eight hundred and seventy-four.
Witness,
JOHN H. LEWIS,
Engineer,
Elgin Road,
Addiscombe,
roydon.
ALFRED BELT. (L.S.)