Air Valve Mechanism for Water-mains.
Year: 1893

page_text: Date of Application, 30th Mar., 1893
Complete Specification Left, 28th Dec., 1893-Accepted, 17th Feb., 1894
PROVISIONAL SPECIFICATION.
Air Valve Mechanism for Water-mains.
I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the City
of London, Civil Engineer and Chartered Patent Agent, do hereby declare the
nature of this invention (a communication to me from Charles Thomas Pollit,
of Angas Street East, in the City of Adelaide, South Australia, Draughtsman,) to
be as follows:-
This invention relates to automatic air valve mechanism for permitting air to
escape from or to enter water-mains.
In carrying out this invention, a cylindrical casing is connected to a vertical
branch on, or to a branch-pipe from, the main; an opening in the bottom of the casing
communicating with the branch or branch-pipe. From a cavity near the opening,
two passages, one on each side of the casing, lead to the upper end of the apparatus.
The top of the casing is closed by a cover, in which the passages may be continued.
On the top of the cow there is a nozzle, to which a swan-neck bend is attached in
order to prevent dirt fn falling in. The opening through the nozzle is closed by
a winged valve. Thei ve-stem is hollow, and has a small perforation at its upper
extremity. A chambe 'n the interior of the casing contains a float carrying a
spindle, the upper end reof works within the hollow valve-stem. The point of
the spindle is adapted fit against a seat at the end of the hollow stem, so as to
prevent the escape of water through the perforation. The sides of the upper end
of the spindle are flat; communication being thus afforded between the perforation
and the upper end of the chamber when the extremity of the valve-spindle is not
against its seat. The lower end of the spindle works in a guide in the casing. The
float is hollow; and has no bottom. Two small openings are made in the bottom of
the chamber immediately above the branch: The seating for the valve in the
cover, and the guide for the lower end of the spindle, may be made separately.
The action of the apparatus is as follows:-When the main is empty, the float,
spindle and valve are in their normal or lowest position; the valve being open.
While the main is being charged, air escapes past the valve. After the main is
full, water rises in the chamber and lifts the float and spindle; thus forcing the
valve carried by the spindle against the seating in the cover; thereby preventing
the escape of water. If 'air accumulate in the chamber, water flows from beneath
the-float through-the-openings in the bottom of the chamber until the float and
spindle drop, leaving the valve held against its seating by the pressure from the
main.
When the float and spindle have fallen, air passes between the hollow stem and
the spindle, and escapes through the perforation. Thereupon water rises in the
chamber, lifts the float and spindle, and causes the upper extremity of the spindle
to bear against its seating in the hollow stem and close the perforation; thus
preventing the escape of water. While the main is being emptied, the valve opens
and admits air; thus ensuring a free outflow of the water.
Dated the 30th day of March 1893

page_text: I, GEORGE GATTON MELHUISH HARDINGHAM, of 191, Fleet Street, in the
City of London, Civil Engineer and Chartered Patent Agent, do hereby declare the
nature of this invention (a communication to me from Charles Thomas Pollit, of
Angas Street East, in the City of Adelaide, South Australia, Draughtsman,) and
in what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :--
This invention relates to automatic air valve mechanism for permitting air to
escape from or to enter water-mains.
The construction shewn in vertical section in the accompanying drawing illustrates
the manner in which it is preferred to carry out the invention.
A is a cylindrical casing connected to a vertical branch on, or to a branch-pipe from,
the main ;
an opening A' in the bottom of the casing communicating with the
branch or branch-pipe. From a cavity A² near the opening, two passages A® and
A', one on each side of the casing, lead to the upper part of the apparatus. The
top of the casing is closed by a cover A, in which the passages A³ and A' may be
continued, as shown. On the top of the cover there is a nozzle A, to which a
cap A is attached in order to prevent dirt from falling in. A swan-neck bend
may, however, be substituted for the cap. The opening through the nozzle A is
closed by a valve B having wings B'. The valve-stem B2 is hollow, and has a
small perforation B at its upper extremity. A chamber A³ in the interior of the
casing contains a float C carrying a spindle C¹, the upper end whereof works within
the hollow valve-stem B³. The point C2 of the spindle is adapted to fit against a
seat at the end of the hollow stem B³, so as to prevent the escape of water through
the perforation B³. The sides of the upper end of the spindle are flat; communi-
cation being thus afforded between the perforation B³ and the upper end of
the chamber A when the point C2 of the valve-spindle is away from its seat. The
lower end of the spindle works in a guide D screwed into the bottom of the
chamber AB in the casing A. The float C is in the form of a hollow cylinder closed
at the upper end and open at the lower end. Any other suitable float, for example
a closed glass bulb furnished with a metal peg at each extremity, may however be
employed. Two small holes D' and D³ are made in the guide D, and effect
communication between the lower part of the chamber A and the cavity A³
immediately above the branch. The seating E for the valve B and the guide D
for the spindle C₁ are preferably made separately, as shown, but they might be
formed as parts of the cover and casing. is a collar pinned on the spindle C'
and adapted to engage with the sides of a slot in a hollow projection B on the
bottom of the valve B.
The action of the apparatus is as follows:-When the main is empty, the float C,
spindle C¹ and valve B are in their normal or lowest position; the valve being open.
While the main is being charged, air escapes through the passages A³ and A* and
past the valve B. After the main is full, water rises in the chamber A³ and,
pressing on the confined air, lifts the float C and spindle C₁; thus forcing the
valve B, which is carried by the spindle, against the seating E in the cover A';
thereby preventing the escape of water through the aperture controlled by the
valve B. If air accumulate in the chamber As, water flows from beneath the
float C through the openings D1 and D2 until the float and spindle drop, leaving
the valve B held against its seating E by the pressure from the main. When the
floa: C and spindle C¹ have fallen, air passes between the hollow stem B' and the
flat sides of the upper end of the spindle, and escapes through the perforation B³.
Thereupon water rises in the chamber As, lifts the float and spindle, and causes
the extremity C of the spindle to bear against its seating in the hollow stem and

page_text: close the perforation B³; thus preventing the escape of water.
While the main
is being emptied, the valve B opens and admits air; thus ensuring a free outflow
of the water. Should the valve B adhere to its seating E, the collar C3 bears
against the bottom of the hollow projection B'; thus causing the weight of the
float C and spindle C' to act on the valve and disengage it from its seating.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I claim :-
1. The improved air valve mechanism for water-mains constructed or operating
substantially as described with reference to the accompanying drawing.
2. For permitting air to escape from or to enter water-mains, air valve mechanism
constructed substantially as herein described and comprising a casing having an
opening communicating with the main, a chamber within the casing above the
opening, passages leading from a cavity below the chamber to the upper end of
the apparatus, a float and spindle within the chamber, a valve carried by the float,
a perforation in the valve controlled by the point of the spindle, and holes for
affording communication between the lower part of the chamber and the cavity
above the opening.
Dated the 15th day of December 1893
G. G. M. HARDINGHAM.