Improvements in Siphons.
Year: 1894

page_text: Date of Application, 24th July, 1894-Accepted, 15th Sept., 1894
Improvements in Siphons.
I, RUSSELL THAYER, residing at Ridgeland, Philadelphia, State of Penn-
sylvania, United States of America, Engineer, 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 following is a Specification of my said invention, reference being had to
the accompanying drawing, which represents a vertical central section through.
the apparatus.
The object of my invention is to prevent the occurrence of accidental leakage
from siphons, owing to breaks or perforations in the pipe.
It is well known that where a substantial perforation, capable of admitting
air to the interior of a siphon pipe, occurs above the level of equilibrium of
the two columns in the respective arms of the siphon the liquid will no longer
continue to flow. Where, however, such leak occurs at a point in the long
arm of the siphon below the line of equilibrium of the two columns, the siphoning
action may continue without interruption.
Where siphons are employed for the conduct of inflammable or destructive
fluids as, for instance, gasoline, petroleum, acids and the like, the consequences
of such leaks may be very serious; especially where, as in some instances, the
flow of liquid is intended to be stopped by a faucet at the lower end of the
longer arm over night, or during any period when the apparatus is not under
inspection.
By my invention a means is provided whereby a leak occurring at what other-
wise would be a dangerous point automatically acts to cause the discontinuance
of flow through the apparatus, the subsequent discharge being limited to the
fluid which is actually contained at the moment within a portion of the siphon
pipe.
In principle the apparatus may be said to consist practically in transferring the
location of a leak of the siphon pipe to such point as will, by the introduction of
atmospheric air, break the column. Theoretically the point to which the leak is
to be thus transferred may be anywhere above the line of equilibrium of the two
columns; but, for practical reasons, I prefer to locate it as in the apparatus of the
accompanying drawing, which will now be described in detail.
In said drawing, A represents the receptacle for liquid, a, which is to be
discharged to a lower level. B represents the siphon pipe proper having a short
arm located near the bottom of the tank, A, and a long arm which is provided
with a stop-cock, D, controlling the outlet of liquid at the nozzle, d. The siphon
proper, B, is provided, preferably at a point in its highest level, with an opening, b.
A continuous, closed casing, C, surrounds the siphon pipe, B, so as to leave an air
space which communicates with the opening at b.
In the instance shown the casing is provided with an offset, c, to accom-
modate the raised flange with which I prefer to provide the said opening, b.
The line x, x, indicates the level at which the two columns of liquid are in
equilibrium.
The operation of the device is as follows:
So long as the casing, C, is intact, the siphoning action once induced in the
pipe, B, will continue, the air normally contained in the space between the
casing, C, and the pipe, B, being inert so far as any tendency to enter
the opening at 6 is concerned; but the moment that any breakage or perforation

page_text: occurs in the casing, C, the air will flow in and enter the siphon pipe proper, B,
at the opening, b. The effect will of course be to break the column of liquid,
and as soon as the liquid has been discharged from the long arm of the siphon
and that portion of the intermediate pipe which is between the long arm and
the opening, b, the flow will absolutely stop.
Incidentally, of course, the casing, C, serves to protect the siphon pipe
proper, B, from accidental injury; but such protection is not the primary object
of my invention, and, as I am aware that the use of jackets or casing for pipes
is not new, I do not claim the same.
In the accompanying drawing I have shown the casing, C, as surrounding
the siphon pipe practically throughout its entire length; but I do not limit my
claim to this particular embodiment, since it is of course only necessary, for
purposes of safety, to surround those portions of the pipe at which a leak would
be attended with dangerous results, and to effect in any way a communication
between such limited casing and the part of the siphon pipe where the admission
of air would operate to break the column. Hence in my claim, when I refer
to the casing as enclosing the siphon pipe, I wish to be understood as not
necessarily implying that the entire pipe is thus enclosed, it being within the
purpose of my invention to limit the extent of the casing to such part of the
pipe as needs the safeguard thus afforded.
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 :-
The combination with a siphon pipe, having an opening above the level of
equilibrium in its two arms, of a closed casing surrounding the said pipe and
communicating with said opening, substantially as set forth.
Dated this 24th day of Jul. 1901
CARPMAEL & Co.,
Agents for the Applicant.