Improvements in Dry Gas Meters.
Year: 1890

page_text: Date of Application, 8th Aug., 1890-Accepted, 13th Sept., 1890
Improvements in Dry Gas Meters.
1 JOHN FOXALL of Newport in the County of Monmouth, Gas Meter Maker,
do hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:-
The object of this invention is to remove from dry gas meters certain defects
to which they are liable, both in respect of their endurance and of their working.
It is well known that the flexible perimeters, or creased annular portions of the
measuring chambers forming the connections between the movable metallic discs and
the central partition of the gas meter case, are liable to lose their shape and crumple
up under the action of the meter, and eventually to crack at the accidental creases
thereby formed. From this cause the accuracy of measurement is interfered with,
and an undue stress is put upon the flexible portions of the measuring chambers. To
prevent this crumpling and cracking of the leather or other flexible material employed,
propose to insert a stiffening ring or rings in the annular crease or creases of the
leather. By this mode of stiffening the flexible connections of the measuring chambers,
the formation of any creases in the leather, other than those provided by the manu-
facturer, is effectually prevented.
In the accompanying drawing I have shewn so much of the internal construction
of a dry gas meter, as will serve to explain the application of my invention thereto.
Fig. 1 shews the gas meter in vertical section, the flexible perimeters of the
measuring chambers being fitted with metallic rings according to my invention,
and Fig. 2 is a detached view of one of the measuring chambers in end elevation.
A, Fig. 1, is the meter case, and B is the central cross partition to which the
measuring chambers are secured in the ordinary manner.
These chambers are composed each of two flanged hoops CC, connected together
by an annular band of leather or other flexible material D, forming the creased
perimeter of the chamber. The one hoop C is made fast to the central partition,
while the other is connected with the movable metallic disc E, which forms a gas-
tight joint therewith.
The disc E of each measuring chamber is connected to a vertical rock shaft F, by
being hinged as usual to an arm projecting from that rock shaft, and it is from
these rock shafts F that the movement of the slide valves, for the admission and the
discharge of the gas is derived, as is also the movement of the counting apparatus.
In applying my invention to this class of meter, I insert, in the crease of the
flexible perimeters of the chambers, a ring of block tin wire or equivalent non-corrosive
material, but when the meter to be fitted is of a large size, preferably a tubular ring
of block tin.
When, however, the invention is applied to, say, 10 light meters or small meters,
block tin wire will serve for the metallic ring G.
By this simple addition of a metallic ring to the measuring chambers, while
avoiding all obstruction to the free movement of the metal discs forming the moving
sides of the chambers, I ensure the proper action of the flexible peripheries of the
chambers. This is due to the rings maintaining or rendering permanent the circular
shape of the flexible peripheries D.
In securing this permanence of shape, I obtain two distinct advantages, viz.: (1) an
increase in the durability of the meter, and (2) the maintenance of its accurate
measurement, the metallic rings ensuring the complete expansion of the measuring
chambers, whatever variation there may be in the pressure of the gas passing through
the meter.

page_text: Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The application to the flexible perimeters of dry gas meter measuring chambers,
of metallic rings or their equivalent, as and for the purpose above set forth.
Dated this 8th day of August 1890.
NEWTON & SON,
Agents for the Applicant.