Combined Tap and Air Valve for Domestic Water Supply.
Year: 1891

page_text: Date of Application, 16th Dec., 1891-Accepted, 13th Feb., 1892
COMPLETE SPECIFICATION.
[Communicated from abroad by MAX THEODOR WILHELM ROSEMANN, Engineer,
and FRIEDRICH WILHELM POESKE, Gasfitter and Plumber, both of Stettin,
in the German Empire.]
Combined Tap and Air Valve for Domestic Water Supply.
I RIDLEY JAMES URQUHART of 57 Barton Arcade, Manchester in the County
of Lancaster, Consulting Engineer and Patent Agent 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 pipes for domestic water supply can seldom be so arranged in the houses
that they are really secure against frost and do not become frozen up during severe
frosts. The freezing can be prevented by shutting off the supply of water and
emptying the pipes, but this is only possible if air is freely admitted to the pipes.
Thus when the main stop cock or valve provided with an outlet for emptying the
pipes is turned off, the upper taps must be opened so that air can enter through
them into the pipes and permit the water to flow out. This circumstance is
known to few house-holders or house porters; to others it is too inconvenient
to mount to the upper stories and open the taps that may be placed there.
Even where this is not the case other circumstances may prevent the precautions
being carried out. A tenement in which the tap requires opening may be locked
up or the tenants refuse to allow the tap being opened because they fear that it may
not be closed before the supply is turned on again and their dwelling he flooded.
To remedy these drawbacks sometimes back-pressure or air valves are placed
upon the highest point of the piping, but generally these are not a certain remedy.
The air valves are liable to become dusty and dirty by the admission of air and
have to be cleaned at times in order to work properly at the required time, but this
cleaning is seldom regularly effected by the occupier of the dwelling containing
the air valve. A safety apparatus however which does not act with certainty in
case of need assures no safety and may as well be omitted. In addition to this in
a system of piping with many branches not only the main pipes but also the
ends of the branches in which a vacuum may be produced by letting off the water
must be furnished with air valves. As this frequently causes inconveniences, they
are usually omitted.
However even if air valves are arranged in all the places where they are
required and are attended to, they are nevertheless subject to ordinary wear or
may be dirtied by impurities in the water so that they do not close tightly and
water escapes through them when the supply is turned on again. If the leakage
is considerable, so that it is noticed at once, this evil can be remedied by shutting
off the supply, but if the leakage is small and not observed at once, walls,
joists etc. may be gradually soaked with water and permanently injured. For all
these reasons back pressure air valves are very rarely applied to domestic water
pipes.
The object of my invention is to remedy all these defects and my invention
consists in the arrangement of a back pressure or air valve in the body of the water
tap by means of which not only is air admitted to the pipes at the required
place but the air inlet is also kept clean and free from dust, and if from any cause
the air valve does not close tightly, the leakage is at once observed and can never
cause any further damage.
On the sheet of drawings appended hereunto
Figs. 1 and 2 show sections of the combined tap and air valve with the valves in
two positions.
CL

page_text: The tap A is shewn as a screw tap with an indiarubber diaphragm a', but may
be of any other ordinary construction of valve tap. Behind the partition a dividing
the inlet passage or bore b from the outlet e a valve B is arranged with a passage C
or equivalent tube leading from the outlet to the underside of the valve B, which
opens into the inlet bore .
When the water is turned on, the pressure in the inlet bore keeps the valve B
closed, and when the valve a¹ a² is opened, the water flows out in the usual way
(Fig. 1). When frost occurs and the principal three way stop cock d (Fig. 3) is
turned so that the water can flow out of the pipes and a vacuum is produced in them
by the descending column of water, the air entering below the valve B3 through the
outflow bore and passage C opens this valve (Fig. 2) and air enters the pipes, so
that they are completely emptied.
As the water continually acts on the valve B and the bore c is always kept clean
by the outflowing water, the valve B is perfectly secured against dust and if it
should become leaky through some cause or other, the percolating water flows
directly into the sink D, so that no further inconveniences are caused thereby.
The leakage also becomes at once visible and an examination of the tap will show
at once whether this is caused by the defective state of the valve a' a² or B.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
Firstly. In taps for domestic water supply the arrangement of a by-passage (C)
connecting the inlet bore () to the outflow bore (c) and of a valve (B) in said
passage arranged in such a manner that it opens when a vacuum is produced in the
inlet bore (b) or pipe connected to it.
Secondly. The combination of a water tap and an air or back pressure valve
substantially as hereinbefore described and illustrated by the drawings.
Dated this 15th day of December 1891
R. J. URQUHART,
57, Barton Arcade, Manchester, Consulting Engineer and Patent Agent.