IMPROVEMENTS IN GAS METERS
Year: 1873

page_text: LETTERS PATENT to William Alfred Telling and Samuel Johnson,
both of Wood Green, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN GAS METERS."
".
Sealed the 18th November 1873, and dated the 19th May 1873.
PROVISIONAL SPECIFICATION left by the said William Alfred Telling
and Samuel Johnson at the Office of the Commissioners of Patents,
with their Petition, on the 19th May 1873.
We, WILLIAM Alfred TelliNG and SAMUEL JOHNSON, both of Wood
Green, in the County of Middlesex, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN GAS METERS," to be as
follows:-
Our Invention relates to that form of gas meter known as a "dry"
gas meter, in which the measurement of the gas passing through the
apparatus is effected by means of a flexible diaphragm to either side of
which the gas is alternately admitted by means of self-acting mechanism,
so that the diaphragm being pressed from side to side alternately

page_text: increases and diminishes the capacity of the two parts of a chamber
which it divides, and by means of self-acting registering apparatus
indicates the number of its oscillations and consequently the cubic
contents of the gas which passes through and actuates it.
Our present improvements are especially applicable to dry gas meters,
for the method of construction of which we obtained Her Majesty's
Letters Patent, dated February 22nd 1871, and numbered 469, entitled
'Improvements in the Construction of Dry Gas Meters," and have
for their object greater simplicity of construction of the meters,
improved methods of arranging and actuating the indicating apparatus
and of balancing the diaphragm, and of forming and arranging and
balancing the weighted arm by which the slide valve is actuated, so
that the pressure upon it is more directly in the required direction, and
the friction is consequently reduced.
In the Specification of our former Patent already referred to we
describe the meter as being constructed of a case divided into upper and
lower compartments by a horizontal partition, the lower compartment
containing a leather diaphragm and a "flag wire" or spindle, which is
actuated by the moving diaphragm and carries at its upper end an arm
which carries two adjustable pins. These two pins actuate a weighted
lever fixed upon a rocking shaft, one end of which carries a bent arm
which drives a slide valve backwards and forwards, by which the gas is
admitted alternately to either side of the diaphragm, whence it passes
through the slide valve to the exist pipe. The rocking shaft also carries
a catch working into a toothed wheel which drives an index recording
the oscillations of the diaphragm and the quantity of gas passing through
the meter.
One part of our improvements consists in attaching to the registering
apparatus an oscillating "pallet” or forked lever which drives a pallet
wheel, or wheel having angular teeth so formed and arranged that when
the pallet is made to oscillate the wheel is made to move round both in
the forward and backward movement of such oscillation. The wheel is
geared with other toothed wheels properly proportioned to drive the
registering apparatus at the proper speed to indicate accurately the
quantity of gas passing. The pallet is made to turn loosely upon a screw
or centre attached to the registering apparatus or to the body of the
meter, and one of its arms or a lever attached to it is connected by a

page_text: wire rod to an arm or lever attached to the spindle or
that it is set in operation by the oscillations of the latter.
66
"
flag wire, SO
The plate by which the lower part of the meter is divided into two
parts and to which the diaphragm is attached may be arranged at or
near the centre of the meter, but we prefer to arrange it in such a
position that it divides the lower part of the meter into unequal parts, and
we make the diaphragm expand and contract into the larger of these two
parts without passing through the dividing plate into the smaller one,
and we make the diaphragm (which may consist of a bag of leather or
other suitable flexible substance cylindrical or nearly so in shape)
sufficiently loose to expand and contract readily to the extent required,
and in order to facilitate the easy and accurate movement of the diaphragm
backwards and forwards we connect a balance weight to it in the
following manner :-
We arrange in the lower part of the meter upon one side of the
diaphragm a vertical lever turning upon a cente at its lower end and
coupled at or near its upper. end to a link the other end of which is
jointed to a plate which occupies the centre of the diaphragm. Upon
this vertical lever we fix a weight which is thrown over to an equal
extent on either side of a vertical line passing through the centre on
which it turns during the stroke of the diaphragm. The balance weight
and the length of this lever are so proportioned to the length of the lever
upon the rocking shaft and the weight upon it that when the diaphragm
commences its stroke it has to lift the former weight, which however
is thrown over the vertical line at the moment when one of the adjust-
able pins commences to lift the weight upon the rocking shaft, and the
former weight accordingly aids the pressure of the gas upon the diaphragm
in lifting the latter one (upon the rocking shaft.)
In order that the action of the weights may approach uniformity, that
upon the rocking shaft should be considerably heavier than that upon the
balance lever. The action is similar in each direction of the strokes. The
weighted balance lever serves to prevent too sudden movement of the
diaphragm upon the admission of the gas at the commencement of its
strokes, and it also serves to render more continuous the expansion and
contraction of the diaphragm and its movement at the times when the
course of the gas is being changed by the action of the slide valve, and
thus to make the flow of gas more equable. The diaphragm may if

page_text: required be made to pass completely through the dividing plate, which is
then fixed in the centre of the lower part of the meter.
In order to prevent the tendency of the weighted lever upon the
rocking shaft in the upper part of the meter to press down the adjustable
pins by which it is driven and the arm which carries them, and thus to
add to the friction of the moving parts, we sometimes make the part of
the lever which is struck by the pins of a curved or cycloidal shape, or
we attach a plate of such curved or cycloidal shape to it, so that the part
struck by the pins is in a position more nearly at right angles to the plane
in which the pins move than if the straight wire itself which forms the
weigthed lever is struck by them. Sometimes we arrange the diaphragm
so as to rise and fall vertically instead of moving horizontally. In such
cases we prefer to make the meter circular in plan, and we balance its
weight by a weighted balance lever and we connect to it the registering
and reversing apparatus already described by means of suitable levers
or rods.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Alfred Telling and Samuel Johnson in 2
the Great Seal Patent Office on the 19th November 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, wc, WILLIAM
ALFRED TELLING and SAMUEL JOHNSON, both of Wood Green, in the
County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her 2
Letters Patent, bearing date the Nineteenth day of May, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said William Alfred Telling and Samuel
Johnson, Her special licence, that we, the said William Alfred Telling a
and Samuel Johnson, our executors, administrators, and assigns, or
such others as we, the said William Alfred Telling and Samuel John-
son, our executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter

page_text: 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 GAS METERS," upon the condition (amongst others)
that we, the said William Alfred Telling and Samuel Johnson, our
executors or administrators, by an instrument in writing under our, or
their, or one of their hands and seals, should particularly describo
and ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause 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 we, the said William Alfred Telling and Samuel
Johnson, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement and accompanying
Drawing (that is to say) :-
$6
Our Invention relates to that form of gas meter known as
dry" gas
meters, in which the measurement of the gas passing through the appa-
ratus is effected by means of a flexible diaphragm, to either side of which
alternately the gas is admitted by means of mechanism operated by the
pressure of the gas itself, so that the diaphragm being pressed from side
to side, alternately increases and diminishes the capacity of the two
parts of a gas-tight chamber which it divides, and by means of self-
acting, registering, and indicating apparatus shews the number of its
oscillations from side to side, and consequently the cubic contents of the
gas which passes through the meter.
Our present improvements are especially applicable to dry gas meters,
for the method of construction of which we obtained Her Majesty's
Letters Patent, dated February 22nd, 1871, and numbered 469, entitled
"Improvements in the Construction of Dry Gas Meters," and they have for
their objects greater simplicity of construction of such meters, improved
methods of arranging and actuating the indicating apparatus, of balancing
the oscillating diaphragm, and of forming, arranging, and balancing the
weighted arm by which the slide valve is actuated, which distributes the
gas to either side of the diaphragm alternately, so that the pressure upon
such arm is more directly in the required direction, and the friction is
consequently reduced.

page_text: In the Specification filed as a condition of our former Letters Patent
already referred to we described the gas meter as being constructed of
a case divided into an upper and a lower compartment by a horizontal
partition, the lower compartment containing an oscillating diaphragm of
thin leather, and a "flag" wire or spindle which is actuated by the
diaphragm, and has at its upper end an arm which carries two adjustable
pins. These two pins actuate a weighted lever fixed upon a rocking shaft
upon which is fixed a bent arm which drives a slide valve backward and
forward by which the gas is admitted alternately to either side of the
diaphragm, whence it passes back through the slide valve to the exit
pipe. The rocking shaft also carries a catch working a toothed wheel
which drives an index, and so records the number of oscillations of the
diaphragm and the quantity of gas passing through the meter.
The first part of our present improvements consists in attaching to
the registering apparatus an oscillating " pallet" or forked lever, which
drives a pallet wheel or wheel having angular teeth so formed and
arranged that when the pallet is caused to oscillate the wheel is made
to move partially round, both in the forward and backward movement
of such oscillation. This wheel is connected by means of other toothed
wheels and pinions with the indicating apparatus so as to drive the
latter at the proper speed to indicate accurately the quantity of gas
passing through the meter. The "pallet" is centred upon a screw or
axis fitted to the body of the meter or to the registering apparatus, and
one of its arms or a lever attached to it is connected by a wire or other
rod to an arm or lever fixed upon the spindle or "flag wire," so that it is
set in operation by the oscillations of the latter.
The plate by which the lower part of the meter is divided into two
parts and to which the diaphragm is attached (as described in our
former Specification already referred to) may be arranged at or near the
centre of the meter, but we prefer to arrange it in such a position that
it divides the lower part of the meter into two unequal parts, and we
make the diaphragm expand and contract into the larger of these two
parts without passing through the dividing plate into the smaller one,
and we make the diaphragm (which may consist of a bag of thin leather
or other suitable flexible substance impervious to gas, cylindrical or
nearly so in shape) sufficiently loose to expand and contract readily to
the extent required, and in order to facilitate the easy and accurate

page_text: movement of the diaphragm backward and forward, we connect a balance
weight to it in the following manner :-
We arrange in the lower part of the meter upon one side of the
diaphragm a vertical lever turning upon a horizontal centre at its lower
end and coupled at or near its upper end to a link, the other end of
which is jointed to a plate which occupies and closes one end of the
diaphragm. Upon this vertical lever we fix a weight which is thrown
over to an equal extent on either side of a vertical line passing through
the centre upon which the lever turns during each oscillation of the
diaphragm. This balance weight and the length of the lever are so
proportioned to the length of the weighted lever upon the rocking
shaft (already described) and to the weight upon such lever, that when
the diaphragm commences its oscillation or stroke it has to lift the
former weight which, however, is thrown over the vertical line (at its
highest point) at the moment when one of the adjustable pins is
commencing to lift the weight upon the rocking shaft, and the former
weight accordingly aids the pressure of the gas upon the diaphragm in
lifting the latter weight (upon the rocking shaft.)
In order that the action of the weights may approach uniformity we
prefer that the one upon the rocking shaft should be considerably
heavier than the one upon the balance lever. The action is similar,
but in opposite directions, in both directions of the strokes or oscillations
of the diaphragm. The weighted balance lever (connected to the
diaphragm as described) serves to prevent too sudden movement of
the diaphragm when the gas is admitted to it at the commencement
of its strokes, and it also renders more continuous the expansion and
contraction of the diaphragm and its movement at the times when
the course of the gas is being suddenly changed by the action of the
slide valve, and thus to make the flow of gas more equable. The
diaphragm may if required be made to pass completely through the
dividing plate to which it is attached, which in such case is arranged
at or near the centre of the lower part of the meter.
In order to prevent the tendency of the weighted lever upon the
rocking shaft in the upper part of the meter to press down upon the adjust-
able pins by which it is driven and upon the arm which carries them, and
thus to add to the friction of the moving parts, we prefer to make that
part of the lever which is struck by the pins of a curved or cycloidal
shape, or we attach a plate of such curved or cycloidal shape to it, so

page_text: that the part struck by the pins is in a position more nearly at right
angles to the plane in which the pins move than if the straight wiro
which forms the weighted lever is itself struck by them. We sometimes
arrange the flexible diaphragm so as to rise and fall vertically instead of
moving horizontally. In this method of arrangement we prefer to make
the meter circular in plan, and we balance the weight of the diaphragm
and the moving parts connected to it by means of a weighted balance
lever, and we connect to it the registering apparatus and the apparatus
for reversing the slide valve already described by means of suitable levers
and rods.
By our improved methods of construction and arrangement greater
simplicity in the construction of dry gas meters is attained than has
heretofore been the case.
The accompanying Drawing is in illustration of our Invention.
Figure 1 is a longitudinal section of a gas meter. Figure 2 is a
transverse section, and Figure 3 a sectional plan of the same.
Figure 4 is a transverse section of a part of the meter shewing the
slido valve. The same letters of reference indicate the same parts in the
different Figures.
a is the body of the meter divided by the plate 6 into the upper part c 2
and the lower part d, and the part d is itself divided by the plate e to
which the flexible diaphragm ƒ (Figure 2) is attached. The vertical
wire or spindle g is connected to the diaphragm ƒ by the arm ½ and the
plate i, and its upper part passes through a stuffing box k in the plate b
and carries the arm to which the adjustable pins m, m', are attached a
by means of the screw n. The pins m, m³, are fitted with friction rollers
preferably of glass. o is a rocking shaft which carries the weighted
lever p which is thrown over from side to side by the pins m, m³, as they
travel backward and forward by the movement of the diaphragm f.
That part of the weighted lever p which is struck by the pins m, m³, is
made of a curved shape, as shewn at » Figure 2, in order to reduce its
downward pressure upon the pins. One end of the rocking shaft o passes
through the stuffing box s into the separate chamber t, into which tho
gas is admitted from the inlet pipe u by the opening and in which the
slide valve w works. This slide valve is driven backward and forward by
a bent arm x upon the rocking shaft o at the moment when the weighted
lever P has been driven sufficiently far by one or other of the pins m, m³,

page_text: to fall over its highest point, and the valve is thus instantaneously
reversed.
A is a pipe communicating from the centre port B covered by the
slide valve (Figure 4) to the gas outlet pipe C. The ports D and E
(Figure 4) communicate respectively with the two parts into which the
meter is divided by the plate e and the diaphragm f, and the gas is
admitted to them alternately by the action of the slide valve, which is
itself driven by the movement of the diaphragm f, as described and
shewn. The stroke of the valve w is limited by the stops 1, 2, and the
movement of the weighted lever p is limited by the stops 3, 4, and the
buffer F. In the lower part of the meter is arranged the weighted
balance lever G turning upon the centre H and connected to the plate i
and the diaphragm ƒ by the link K. The arm or lever L is fixed upon
the wire or spindle g and is connected by the rod M to the pallet N
which oscillates upon the centre O and at each oscillation drives forward
the pallet wheel P, by which the indices of the registering apparatus
(not shewn in the Drawing) are actuated.
The operation of the gas meter is as follows:-The gas is admitted
from the inlet pipe v into the valve chamber t, whence by the action of
the valve w it is admitted to either side alternately of the diaphragm
f, and thus drives the diaphragm and the plate i which covers it from
side to side, the gas being forced during each return stroke of the
diaphragm back through the valve w and the passage A to the outlet
pipe C. The vertical cranked wire g being connected to the diaphragm
f by the arm is caused to make a partial revolution at each stroke of
the diaphragm, and the lever / fixed-upon its upper end thus carries
backward and forward the pins m, m², which strike the weighted lever p.
When the diaphragm fis travelling in the direction shewn in Figure 2
the pressure of the gas has not only to move the diaphragm, but also to
lift the weighted balance lever G, which is so adjusted that it has reached
its highest point at the moment when the pin m² strikes the weighted
lever p, and by its subsequent descent it aids the pressure of the gas to
lift the latter. The pins m, m³, are so adjusted that the weighted lever
2 falls over and instantaneously reverses the action of the valve to at the
moment when the diaphragm has travelled sufficiently far to measure
the exact quantity of gas required; it then instantly commences its
return stroke, during which it has to lift the weighted lever G which
falls over at the moment that the pin m commences to lift the lever p.

page_text: The movement of the diaphragm is thus rendered continuous and
equable, and the steadiness of the escaping gas is not affected by the
sudden reversal of its movements. The cycloidal curve upon the lever p
reduces the friction of the pins m, m³, upon the latter. The action of
the lever N upon the pallet wheel P by moving the latter forward at
each oscillation of the diaphragm in either direction reduces the friction
of the parts which drive the registering apparatus.
Having now described our Invention and the manner in which the
same is to be performed, we claim-
The application of the balance weight and lever to the diaphragm of
dry gas meters for the purpose of rendering the flow of gas more
equable, substantially as described and shewn in the Drawing.
Also the construction of the weighted lever by which the slide valve
is actuated of such a form that the friction upon it is reduced, substan-
tially as described and shewn in the Drawing.
Also the method of driving the registering apparatus of dry gas meters
by means of an oscillating pallet and pallet wheel driven by a lever, as
described and shewn in the Drawing.
In witness whereof, we, the said William Alfred Telling and
Samuel Johnson, have hereunto set our hands and scals, this
Eighteenth day of November, in the year of our Lord One
thousand eight hundred and seventy-three.
MATT TITA