Improvements in or connected with the Starting Syphons of Flushing Cisterns.
Year: 1892

page_text: Date of Application, 17th Aug., 1892-Accepted, 1st Oct., 1892
COMPLETE SPECIFICATION.
Improvements in or connected with the Starting Syphons of
Flushing Cisterns.
I, WALTER BROWN. HARVEY DRAYSON, of 2 Newgate Street, in the City of
London, Sanitary Engineer, do hereby declare the nature of the said invention
and in what manner. the same is to be performed to be particularly described and
ascertained in and by the following statement, reference being had to the
accompanying sheet of drawings and to the letters and figures marked thereon,
that is to say :-
In flushing cisterns for water closets, urinals and the like in which the flush is
started by means of a syphon, the entrance of air into the short leg of the syphon,
when the level of the water in the cistern falls to that of the lower edge of such
short leg, is accompanied by a gurgling sound which it is desirable to prevent.
When the short leg of the syphon is fixed and the syphon action is started by some.
means other than the movement of the said short leg, the gurgling sound is some
times prevented by means of an air valve at the upper part of the syphon, which
valve is opened by means of a float when the level of the water in the cistern falls
to a certain level; air, is thus admitted to the syphon without passing between the
surface of the water and the lower edge of the short leg of the syphon and there-
fore without producing the objectionable sound above referred to. When however
the short leg of the syphon is made movable and, as is usually the case, in the
form of a bell surrounding the upper end of the longer leg of the syphon so that
the syphon action can be started by forcing down the said bell, or in some cases by:
raising the same, the application of the aforesaid air valve has not heretofore
been found practicable because the somewhat sudden movement of the bell necessary.
to start the syphon causes the valve to jerk open and prevent the establishment of
the syphon action.
The object of the present invention is to provide means whereby an air valve
can be applied to the moving part or bell of a syphon without opening when the
said bell is moved, and for this purpose I employ an arrangement of apparatus such
as that shown in the accompanying drawings in which
Figure 1 is a sectional elevation of a flushing cistern syphon: the short leg of
which can be lowered vertically in order to start the syphon in the mauner well
understood in connection with this class of apparatus;
Figure 2 is a plan of same.
A is the upper end of the longer leg of the syphon, B the movable bell forming
the shorter leg of the syphon. C is an air passage formed in a tubular casting C
fixed airtight to the top of the bell B. D is a valve closing the upper end of the
passage C. The valve D is secured to the short arm E of a bell crank lever, the
longer arm El of which is furnished with a counterbalance weight E. The bell]
crank lever E E' is pivoted to a bracket F by means of a pin-joint G. The
counterbalance weight E' tends to keep the valve D closed against its seat at the
end of the passage C. The valve D is provided with a link or arm J pin-jointed
to it at H and having formed therein a slot K. L is a bracket cast with, or fixed
to, the tube C or to any convenient part of the bell B. A bell-crank lever M
turas on a fulcrum pin N of the bracket L and a pin P fixed in the shorter arm
of the lever M takes into the slot K in the pivoted link or arm J. The longer
arm of the bell-crank lever M has suspended to it a float Q by a rod R.
It will now be understood that on pushing the bell B downward by the usual.
lever, not shown in the drawings, acting on the trunnion pins B' into the position.
shown in Figure 1, in order to raise the water in the bell B above the upper end.
of the longer leg A as shown, and thereby to start the syphon, the tube C¹, valve D,

page_text: bell crank lever E E¹, weight E, link or arm J, bracket L, lever M and float Q
are lowered with it, but as the float Q is constantly tending to rise in the water in
the cistern S in which it is immersed, it presses the lever M upwards so as to force
the pin P against the upper or inner end of the slot K thereby holding the valve D
firmly closed against its seat during the downward movement of the bell B; but
when the said downward movement of the bell B is suddenly stopped by the studs T
coming in contact with the bottom of the well S₁ of the cistern S, the momentum
of the float Q carries it somewhat further down and relieves the pressure of the
pin P more or less from the upper or inner end of the slot K, and the valve D would
be left more or less free to 'open were it not for the weight E' and bell crank
lever E E which keep it closed notwithstanding the relief of the pressure of the.
float Q. The slot Kenables the pin P to move backwards slightly without opening
the valve D. When the level of the water in the cistern S.has been lowered
sufficiently, the float Q falls and the pin P then comes against the lower or outer:
end of the slot K and opens the valve D against the action of the weight E. Air
then enters the bell B through the passage C and the syphon action is broken
without the level of the water in the cistern falling low enough to allow air to
enter between the surface of the water and the lower edge of the bell, and to
produce the gurgling sound above mentioned. When the level of the water in the
cistern S rises again, the float Q rises, the pin P comes against the upper or inner
end of the slot K and co-operates with the weight E' to press the valve D firmly
against its seat in readiness for the next flushing operation...
The bell B with its attendant parts is raised again in the usual way by a
counterbalance weight (not shown in the drawings) or otherwise as may be]
convenient.
The above described arrangements are equally applicable to cases where the
bell forming the short leg of the syphon is raised to start the syphon action instead
of being depressed; the only difference in the action being that the weight E
keeps the valve D closed while the bell is ascending and when the ascent of the
latter is more or less suddenly stopped, and the pressure of the weight E' on the
valve D momentarily relieved by the jerk, the upward momentum of the float Q
presses the pin P against the upper or inner end of the slot K and holds the valve D
closed until the upward momentum of the weight E' is exhausted and the said
weight is free to exert its pressure upon the valve to keep it closed until opened
by the downward movement of the float Q as the water in the falls as. before
described.
If preferred, a' spring may be employed instead of the weight E' for keeping the
valve D closed..
Having now particularly described and ascertained the nature of the said 'inven-
tion and in what manner the same is to be. performed, I declare that what I
claim is:
First. In the starting syphon of a flushing cistern in which the shorter leg of
the syphon is lowered to start the syphon action, the combination, with an air
valve which is kept closed by a float and lever while the shorter leg of the syphon
is being lowered, of a weight or a spring adapted to keep the said valve closed
when the aforesaid float and lever are rendered nomentarily inoperative to keep
the said air valve closed when the shorter leg of the syphon is suddenly brought
to rest, substantially as herein before described, and illustrated in the drawings.
Second. In the starting syphon of a flushing cistern in which the shorter leg of
the syphon is raised to start the syphon action the combination, with an air valve
which is kept closed by a weight or spring while the shorter leg of the syphon is
being raised, of a float and lever adapted to keep the said valve closed when the
aforesaid weight or spring is rendered momentarily inoperative to keep the said
air valve closed when the shorter leg of the syphon is suddenly brought to rest;
substantially as hereinbefore described, and illustrated in the drawings.
Third. In the, starting syphon of a flushing cistern in which the shorter leg of

page_text: the syphon is movable to start the syphon action, the mechanism consisting of a
weighted or spring-urged air valve and a float and lever connected to the valve by
a pin and slot, combined, arranged and operating substantially as hereinbefore
described, and illustrated in the drawings and for the purpose specified.
Dated this 17th day of August 1892.
W. B. H. DRAYSON,
Per W. H. Beck,
115, Cannon Street, London, E.C., Agent.
W. B. H. DRAYSON,
Per W. H. Beck,
115, Cannon Street, London, E.C., Agent.