IMPROVEMENTS IN ALARMS OR APPARATUS FOR INDICATING A DEFICIENCY OF WATER IN CISTERNS OR IN BOILERS USED FOR DOMESTIC PURPOSES
Year: 1864

page_text: LETTERS PATENT to John Griffiths, of Penrhyn Terrace, Stretford, in the
© County of Lancaster, Gentleman, and John Jaffrey, of Booth Street, in
the City of Manchester, Plumber, for the Invention of "IMPROVEMENTS IN
ALARMS OR APPARATUS FOR INDICATING A DEFICIENCY OF WATER IN CISTERNS
OR IN BOILERS USED FOR DOMESTIC PURPOSES."
Sealed the 29th July 1864, and dated the 16th March 1864.
PROVISIONAL SPECIFICATION left by the said John Griffiths and John
Jaffrey at the Office of the Commissioners of Patents, with their Petition,
on the 16th March 1864.
We, JOHN GRIFFITHS, of Penrhyn Terrace, Stretford, in the County of
Lancaster, Gentleman, and JOHN JAFFREY, of Booth Street, in the City of
Manchester, Plumber, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN ALARMS OR APPARATUS FOR INDICATING A DEFICIENCY OF WATER
IN CISTERNS OR IN BOILERS USED FOR DOMESTIC PURPOSES," to be as follows :---
The object of our Invention is to give alarm or notice when the water
supply to cisterns or to boilers for domestic pnrposes becomes deficient, or when
the water in a cistern or in the pipes leading from a cistern to a boiler used for

page_text: domestic purposes has descended below a given level, and our Invention
consists in arranging a vessel at about such given level, and so that it com-
municates with the water in the cistern or pipes above the said level, and in
placing in this vessel an arrangement acting upon the principle of the "mush-
room valve, being free to open and shut when permitted by absence or presence
of water at the said level, and in placing also in the said vessel a ball or other
float, so that when the water is above the given level this float will have suffi-
cient buoyancy to press the valve outwards against its seating and prevent any
escape of fluid, and at the same time hold a catch firmly in connection with the
alarm mechanism, but when the water descends below the given level, then the
float will fall and release the valve, which in moving will liberate the catch of
the alarm mechanism. The arrangement termed the mushroom valve is not
intended for the purpose of passing fluid, but as a means of transmitting the
movements of the float through the side or top of the closed vessel without
friction, or with as little as possible, and it is constructed on the mushroom
valve principle, so that though perfectly free when the fluid is below the given.
level and there is no fluid to escape, it will be closed against the escape of
fluid when there is a sufficient supply. In place of the mushroom valve a
flexible or elastic diaphragm may be used. The valve spindle is connected to
a lever, which has a catch on its end that enters the teeth of a ratchet wheel,
which is prevented by this means from rotating so long as the valve spindle is
pressed outwards with sufficient force, but it lifts out of the teeth and releases
the ratchet when the float drops or withdraws from the valve. This ratchet
wheel is in connection with ordinary clockwork mechanism for striking a bell,
which is put in motion by a spring or weight. Instead of the catch entering
the teeth of a ratchet wheel, it may be made to press on an escape or break.
Instead of sounding an alarm, the apparatus may be made to move a plate or
pointer placed in a conspicuous position.