A SAFETY ANTI VACUUM VALVE
Year: 1884

page_text: I, HORACE SWETE of Baskerville House Worcester Doctor of Medicine, Medical
Officer of Health Droitwich Urban and Rural Sanitary Districts do hereby declare
the nature of my invention for A SAFETY ANTI VACUUM VALVE to be as
follows:-
A hollow dome of iron with a hole at the narrow end one third of the width of
the wide end fitted inside with an India rubber collar and having a screw cut on
its wider end to enable it to be screwed on a Tee piece attached to the water
service pipe-inside this dome is placed a ball of wood, hollow metal or other
substance capable of floating in water with a rod attached to it passing through
the hole in the dome at the wider end just above the screw, are two or more rods
of metal passing accross it to prevent the Ball from falling into the pipe to which
it is screwed or otherwise fastened beneath. I also propose when required to con-
struct this rod, of metal passing through the Ball so that the lower end of the rod,
when it falls to the bottom of the service pipe may serve to completo an electrical
circuit to deflect a needle or ring a Bell at the Pumping Station, the upper part of
the rod I propose to connect if required to a lever or other apparatus to mark off
the rise and fall of the Ball upon a revolving Drum, so as to indicate the fluctuations
or stoppage of the water supply.
When the supply of water is full on the Ball will float to the top of the Dome
sealing it by pressing against the rubber collar, when the supply fluctuates or is
shut off, the Ball will fall letting in air, so as effectually to prevent any vacuum
being formed in the water pipes, and thus also to prevent any suction into the
water, of gases from sewers, drains or water closets, that may be near the joints or
taps of the water pipes.
D

page_text: case a can be regulated. When the water is full on, the pressure forces the float
into the aperture d of the diaphragm & effectually closing the said aperture and
preventing the passage of air from the holes 6' in the dome into the water-pipe,
but on the supply fluctuating or being shut off the float e falls and air is admitted
to the pipe through the holes 62, in the dome b and the aperture in the
diaphragm.
For mains or service pipes with high pressure I construct the valve as shown in
figures 3, 4, 5 and 6. In this case I form the diaphragm d of metal and provide
the port or aperture & with a bushing d² of brass, or other suitable material
forming a valve-seat. The float e may consist of layers e¹ of cork or other suitable
material resting on a flange fl on the rod f. The top of the float e carries a rubber
or other suitable washer e² the whole being compressed by the plug 6 screwing
upon the rod f. The two portions ab of the case with the interposed diaphragm a
are united by bolts and nuts c¹. The holes 6s in the dome b enter the said dome
laterally and are covered, when necessary, by a protecting flange or rim 63 on the
top of the dome, so as to prevent the entrance into the said holes of sand and dirt.
The action of this valve is the same as that above described. The pressure of
water beneath the float forces the said float and rod upward and causes the plug
or stopper to enter the port or aperture d' and the washer 2 to be forced
against the under surface of the bushing d³ effectually sealing the said port or
aperture d¹.
My improved valves may be constructed of any suitable shape and size and
I do not limit myself to the exact details herein shown and described as the same
may be varied without departing from my invention, but
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
In an anti-vacuum valve for water-pipes and mains, a case or dome having an
internal diaphragm and air-inlet passages above the said diaphragm, the said
diaphragm having a port or aperture for the passage of air into the pipe or main,
in combination with a float or float-valve which closes the said port by the pressure
of water within the said case substantially as herein set forth.