IMPROVEMENTS IN LIQUID METERS
Year: 1875

page_text: PROVISIONAL SPECIFICATION left by Benjamin Joseph Barnard Mills
at the Office of the Commissioners of Patents, with his Petition,
on the 26th May 1875.—A communication from abroad by Hiram
Stevens Maxim, of Brooklyn, in the State of New York, and United
States of America.
I, BENJAMIN JOSEPH BARNARD MILLS, of the Firm of Harris and
Mills, of 23, Southampton Buildings, in the County of Middlesex,
Patent Agent, do hereby declare the nature of the said Invention for
“IMPROVEMENTS IN LIQUID METERS,” a communication to me from abroad
by Hiram Stevens Maxim, of Brooklyn, in the State of New York, and
United States of America, to be as follows:-
This meter is made with an external casing of cast iron galvanized to
prevent rust. The said casing is in two parts, connected by coupling
screws or bolts which clamp an annular flange projecting from an
internal trunk of square form, through which the water is caused to
flow. The annular flange thus forms a horizontal partion around the
square trunk. Above the trunk is a second partition, from which a
cylinder projects downwards concentrically within the upper end of the
trunk to which it is connected by radial wings, serving to confine the
water to a vertical direction.

page_text: A hollow buoyant shaft revolves within the square trunk and the
round cylinder above it. On the portion of the shaft below the round
cylinder screw blades are provided to impart a rotary motion to the shaft
by the downward flow of the water. Radial webs or wings projecting
inward from the corners of the square trunk prevent the water from
following the rotary movement of the shaft. The buoyant hollow shaft
has a gravity slightly less than that of the water which it displaces, so
that under the pressure of a heavy flow it will be pressed against is
lower bearing or pivot, and when the flow is light it will bear on its
upper pivot.
The upper pivot is made small to reduce the friction; the lower pivot
is made larger for durability.
The upper end of the trunk is surrounded by a screen of wire gauze
to exclude fish or other solid bodies. For the same purpose a gauzo
diaphragm may be applied within the coupling of the pipe, through
which water is introduced to the casing above the partition surrounding
the square trunk.
The rotary motion of the shaft is transmitted through a train of
diminishing gear to a registering apparatus located in a dry bonnet at
the top of the meter.
The communication from the water chamber to the dry bonnet is
through the medium of a vertical worm shaft formed with a conical
collar ground upon a seat, against which it is held by the action of a
spiral spring, so as to form a water-tight joint. The gear shaft below
communicates with the transmitting shaft by an arm on the former
engaging with a crank arm on the latter, so that they need not be
mounted accurately in line.
To maintain the buoyancy of the hollow scrow shaft a small quantity
of suitable chemicals, such as bicarbonate of soda and tartaric acid is
supplied in its lower end, whereby, in event of the influx of water,
immediate evolution of carbonic acid gas will dovolop an internal
pressure, preventing further influx of water.