IMPROVEMENTS IN DRY GAS METERS
Year: 1866

page_text: LETTERS PATENT to David Cohen, of No. 24, Leigh Street, Burton
Crescent, in the County of Middlesex, Gas Meter Maker, for the
Invention of "IMPROVEMENTS IN DRY GAS METERS."
Sealed the 30th October 1866, and dated the 2nd May 1866.
PROVISIONAL SPECIFICATION left by the said David Cohen at the
Office of the Commissioners of Patents, with his Petition, on the 2nd
May 1866.
I, DAVID COHEN, of No. 24, Leigh Street, Burton Crescent, in the County
of Middlesex, Gas Meter Maker, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN DRY GAS METERS," to be as follows:-
In the construction of dry gas meters the measuring compartments are
formed by means of a moveable or flexible diaphragm.
The first part of my improvements consists in the construction of the frame
of the diaphragm; the material of the outer frame is doubled and liberal space
allowed above the usual single frame, giving room for soldering, so that the
flexible part should not be scorched by the act of soldering.
The second part of my improvements relates to the flexible part of the
diaphragm; the double shields are so constructed that the inner shield should

page_text: be fixed to the outer shield by means of grooves, the flexible part lies between
them; this dispenses with the use of glue, which melts through the dampness
of the gas and spoils the action of the diaphragm.
The third part of my improvements is on the square valve which works by
rotary action, and over which the section valve passes from one passage to the
other uncovering long openings, and thus emitting a free supply of gas, so as
not to affect in any manner the light, and so as to allow the diaphragm to
work freely. To the angles of the valves I have connected four rings which
work round pins, and these are protected by glass cylinders, so that when
the rings travel round the pins they may not be retarded by them, but pass
smoothly round by aid of the glass cylinders, which turn to give freedom to the
action. The cover or section valve is faced with leather or some other flexible
material so as not to wear the metal valve, and a bar is fixed across the opening
of the valve by me to keep the leather faced cover in its proper position.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said David Cohen in the Great Seal Patent Office on the 2nd
November 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
COHEN, of 24, Leigh Street, Burton Crescent, in the County of Middlesex,
Gas Meter Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of May, in the year of our Lord One
thousand eight hundred and sixty-six, in the twenty-ninth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said David Cohen, Her special licence that I, the said David Cohen, my
executors, administrators, and assigns, or such others as I, the said David
Cohen, 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 THE
CONSTRUCTION OF DRY GAS METERS," upon the condition (amongst others) that
I, the said David Cohen, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and seals, should par-
ticularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be

page_text: 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 David Cohen, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
My Invention of improvements in the construction of gas meters relates to
that description of gas meter commonly called dry gas meter, and in which
the measuring compartments are formed by means of a movable or flexible
diaphragm.
The first part of my improvements relates to the frame of the diaphragm;
the material of the outer frame is doubled, and liberal space is allowed above
the usual single frame to leave a space for soldering, so that the flexible part
may not be scorched in soldering.
The second part of my improvements relates to the flexible part of the
diaphragm; the double shields are so constructed that the inner shield is fixed
to the outer one by means of grooves, which hold the flexible part firmly
between them; this dispenses with the use of glue, which melts through the
dampness of the gas, and at the same time gives extra strength to the edge of
the material.
The third improvement is on the square excentric valve, the upper part of
which passes from one passage to another, uncovering long openings through
which the gas passes freely from one part of the meter to the other. To the
angles of the upper valve I have connected four rings, which rotate round
pins to guide the said upper valve in regulating the covering and uncovering
of the openings. The pins are protected by glass cylinders, so that when the
rings rotate round the pins they may not be deterred by them, but turn
smoothly.
In the accompanying Drawings I have shown various representations of
portions of a gas meter with my improvements applied thereto.
Fig. 1 is a complete section of a meter through the diaphragms; Fig. 2 is
a plan of a meter with the casing removed, so as to show more clearly the
entrance and exit passages for gas, and the mode of operating the square
valves with rings and pins; Fig. 3 is a valve; Fig. 4 is the moveable cover
of valve with its rings.
In Fig. 1, A, A, A, A, is the diaphragm; B, B, is where the outer shield
and inner shield are fixed together, and at the same time holding the leather
or flexible material tight between; C, C, C, C, is the double frame, shewing
my improved method of fixing the leather or flexible material, so as to prevent

page_text: its being affected by the heat of the soldering; D, the valve with pins E in
moveable glass cylinders; F, the moveable cover with the four rings G, G, G, G.
In Fig. 8 I have arranged a division or bridge across the openings, so as to
keep the leather facings of cover, Fig. 4, in easy movement, and to prevent
catching while working over the sharp edges of the valve D.
Having now described my Invention of improvements in the construction
of gas meters, and the manner of carrying the same into effect, I wish it to
be understood that I do not intend to confine myself to the exact arrange-
ment of parts and form herein shown and described, as they may be varied
without departing from the nature and object of my Invention, nor do I intend
to claim all the parts herein shown as of my Invention; but that which I
claim under the above in part recited Letters Patent is,―
Firstly, the double frame of the diaphragm.
Secondly, the grooves in the shields of the diaphragm.
Thirdly, the bridges across the openings of the valve.
And, lastly, the pins with moveable glass cylinders and rings of the valves.
In witness whereof, I, the said David Cohen, have hereunto set my
hand and seal, this First day of November, in the year of our Lord
One thousand eight hundred and sixty-six.
DAVID COHEN.
(L.S.)