Improvements in or relating to Syphon Flushing Cisterns for Water Closets and the like.
Year: 1895

page_text: Date of Application, 2nd Apr., 1895
Complete Specification Left, 2nd Jan., 1896-Accepted, 8th Feb., 1896
PROVISIONAL SPECIFICATION.
Improvements in or relating to Syphon Flushing Cisterns for
Water Closets and the like.
We, WALTER Ross TAYLOR SINCLAIR of 44 Hanover Street, Edinburgh
Plumber, and CHARLES DARRAH, Senior of Miller Street, Manchester Manu-
facturer, do hereby declare the nature of our said invention to be as follows:-
These improvements refer to that class of water closet cistern in which the water
is drained by syphonic action, that is, by a syphon pipe situated in the cistern with
the longer limb connected with the outlet or service pipe and the other or shorter
limb extending downward to within an inch or so of the cistern floor. In this type
of cistern considerable noise is occasioned at the moment the cistern becomes
drained, or at the moment the water level sinks below the open end of the syphon
pipe, owing to the inrush of air into the pipe, and to the vacuum, formed by the
previous discharge of the water, being thereby destroyed.
Now our invention has for its object to prevent the noise aforesaid, and to this
end we employ a tube of about one eighth of an inch bore, which we insert into
the shorter limb of the syphon pipe and connect at one extremity to the side of
such pipe at a point a little above the open end. The opposite and upper end of
this tube terminates at or near the bend of the syphon pipe, and is, by preference
arranged and held centrally in such pipe by a three armed boes or plate.
The lower end of the tube passes through the pipe side and opens into the
cistern interior.
Assuming the action of the syphon to have been started by any of the well-
known means, the water flows through the pipe in the ordinary way until the lower
end of the small tube is uncovered by the water in the cistern. Immediately this
takes place the syphonic action commences to be destroyed and the remaining
quantity of water in the cistern gradually ceases to flow through the pipe until the
lower end of the pipe is uncovered, when the water ceases to flow altogether and
that without the noise aforesaid.
This gradual destroying of the syphonic action may be effected in a variety of
ways as for example, the small tube may be outside the syphon pipe with one
extremity connected say to the apex of the syphon bend, and with its other and
open extremity situated at a point within an inch or so from the open end of the
syphon pipe.
Another way would be to insert a pipe of slightly less diameter in the shorter
member of the syphon pipe, which would form a small annular cavity, and by
communicating through one or more holes at the lower end of the syphon pipe
with the cistern interior would have more or less the same effect as the
small tube.
If desired two or more tubes may be employed for admitting the air at different
stages and if made of different sizes of admitting air in different quantities.
Dated this 1st day of April 1895.
WALTER ROSS TAYLOR SINCLAIR,
CHARLES DARRAH, SENR.,
By John G. Wilson & Co.,
Agents.

page_text: Improvements in or relating to Syphon Flushing Cisterns for
Water Closets and the like.
We, WALTER Ross TAYLOR SINCLAIR, of 44 Hanover Street, Edinburgh,.
Salesman and CHARLES DARRAH, Senior, of the Firm of Baxendale & Co.,
Miller Street, Manchester, Manufacturer, do hereby declare the nature of our
said invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :—
These improvements refer to that class of water-closet cistern in which the water
is drained by syphonic action, that is by a syphon pipe situated in the cistern with
the longer limb connected with the outlet or service pipe and the shorter limb
extending downwards to within an inch or so of the cistern floor. In this type of
cistern at the moment when it is being drained of its contents, and the syphonic
action is being destroyed by the uncovering of the open end of the syphon pipe, a
considerable straining or "gurgling " noise takes place, which is often a source of
annoyance, and renders syphonic cisterns very objectionable in places where
quietness is a desideratum.
Now our invention has for its object to render such cisterns "noiseless," or to
considerably lessen or diminish the noise, and thus render the cisterns fit for use in
all situations.
And in order that our said invention shall be the more readily understood and
carried into practical effect we have hereunto annexed a sheet of drawings and we
will now proceed to describe the same with the assistance of the various figures and
letters of reference marked thereon.
Fig. 1 is a transverse section of the syphon pipe portion of a flush-out cistern, and
Fig. 2 a plan (partly in section) with our improvements applied.
Fig. 3 illustrates a modification of our improvements.
In carrying out our invention we employ a small tube (A) with about th of
an inch bore as illustrated, which we introduce into the shorter limb of the syphon
pipe (B). The lower extremity of such tube we pass through the wall of said pipe,
near the open end thereof, and opening into the cistern interior; and the other end
of such tube terminates, by preference, in the bend of said syphon pipe, and is
held centrally in the pipe by a three armed boss or plate (C).
Assuming the action of the syphon to have been started by any of the well-
known means (say by the lifting of the valve (D)), the water flows through the
pipe in the ordinary way until the lower end of the small tube (A), or the opening
thereinto, is uncovered by the water in the cistern. Immediately this takes place
the syphonic action commences to be destroyed, the uncovering of the tube
permitting the air to enter the pipe (B) at a point where the syphon is strongest,
but the amount of air thus admitted being so slight it permits of the further
discharge of the water to uncover the open end of the syphon pipe, at which
moment the syphonic action becomes nil., or fully destroyed, the sudden admission
of air, which has hitherto caused the "gurgling" noise, thus being avoided.
This gradual destroying of the syphonic action as aforesaid may be effected in a
variety of ways, as for example the small tube (A) may be on the outside of the
syphon pipe with one extremity connected, say to the apex of the syphon bend,
and with its other and open extremity situated at a point within an inch or so from
the open end of the syphon pipe, as shewn in dotted lines in Fig. 1.
Another way consists of a pipe (E) of slightly less diameter inserted in the
shorter limb of the syphon pipe as illustrated in Fig. 3, which forms an annular
cavity (F), and by communicating through one or more holes (G) at the lower end
of the syphon pipe with the cistern interior, has more or less the same effect as the
small tube. .

page_text: If desired two or more tubes may be employed for admitting the air at different
stages, and if made of different sizes for admitting air in different quantities. The
said tube (or tubes) may be led in from any point or part of the syphon pipe,.
provided it is on a slightly higher level than the open end of the shorter limb.
Having thus particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we-
claim and desire to secure by Letters Patent is :—
1st. In syphon flushing cisterns admitting a small quantity of air into the syphon:
pipe, prior to the uncovering of the open end of the shorter limb of the syphon.
pipe, as set forth.
2nd. The use of a small bore tube (A) in, or on the outside, of the syphon pipe-
of a syphon cistern as and for the purposes set forth.
3rd. The use of a tube (E) within the syphon pipe of a syphon cistern in.
combination with holes (G) as and for the purposes set forth.
Dated this 31st day of December 1895.
WALTER ROSS TAYLOR SINCLAIR,.
CHARLES DARRAH,
By John G. Wilson & Co.,
Agents.