Improvements in Syphon Flushing Cisterns and Tanks for Water Closets and for other Purposes.
Year: 1898

page_text: Date of Application, 12th Feb., 1898
Complete Specification Left, 10th Dec., 1898-Accepted, 21st Jan.,
1899
PROVISIONAL SPECIFICATION.
Improvements in Syphon Flushing Cisterns and Tanks for Water
Closets and for other Purposes.
We, FRANCIS MONTAGUE SIMS, of 2, Smedley Lane, Cheetham Hill, Manchester,
Manufacturer, and FRANK TAYLOR HARROP, Brassfounder, and JAMES HERBERT
HARROP, Brassfounder, both of the Firm of Messrs. Harrop Brothers & Co., of
22, Bridge Street, Manchester, all in the County of Lancaster, do hereby declare
the nature of this invention to be as follows:-
In order to improve and simplify the construction of syphon flushing cisterns,
and tanks for water closets, and other purposes, and to meet the more exacting
demands of water companies who insist on the egress pipe being carried not only
above the overflow pipe of the cistern, but even above the top of the cistern itself,
and also that the only egress for fluid from the cistern shall be over the top of
and down said egress pipe thus excluding any system requiring valve or other
openings in the bottom of the cistern, and also to obtain an effective flush with
a short length of egress pipe, our invention is as follows.
We propose to achieve these desired results by appliances acting on pneumatic
principles .e. the fluid is to be raised over the top of the egress pipe, be the height
greater or less by the air acting directly on the surface of the water in the cistern,
without the assistance of any appliances of the nature of force or lift pumps or
otherwise, or by scoops floats or buckets simply raising the water mechanically
by hand.
To achieve our object we cover the top of the egress pipe in the cistern with a
cylindrical arrangement of a special shape or form, first, because we desire to have
in the entire syphon system, as little air as possible, and secondly because it is
necessary to appreciate and reckon with the expansion of air when it expands at
a pressure less than that of the atmosphere, and to calculate the amount of such
expansion according to the mathematical working out of Boyle's law as regards
the said expansion, and also to provide for the reception of the greater bulk of such
expanded volume of air in a space of the smallest possible depth.
In order to reduce the quantity of air in the system we first cover the egress
tube from the water level in the cistern with a cylinder of such diameter, and
height above the top of the egress pipe that the area between the two concentric
cylinders, and the space between the tops of them shall be sufficient to allow a
full and easy flow of the greatest volume of fluid the egress pipe is capable of
carrying off, then the cylinder arrangement is extended horizontally to such an
extent as is required by the volume of air to be dealt with, and the capacity of the
cistern will allow, by which consideration the depth of the said horizontal section
is determined, the object being to obtain the greatest volume of fluid flow down
the egress pipe in the least possible time, and with the smallest possible lift of the
cylinder, having regard to the height of the egress pipe, above the water level
in the cistern.
From the bottom of this extended section of the cylinder the diameter of the
cylinder round the egress pipe is again reduced to that sufficient, to allow a full

page_text: and easy flow under the outer cylinder and up between the two concentric
cylinders.
The egress pipe at its lowest end, the point of ingress into the lower vessel is
fitted with a water trap of a capacity sufficient to seal the end of the egress pipe
against the ingress of air, such capacity being with special reference to the fact
that on lifting the cylinder, fluid will rise in the egress pipe high enough to
reduce the atmospheric pressure in the pipe to a degree of tension equal to atmo-
spheric pressure less the weight of water raised in the cylinder above the water
level in the cistern, whatever that weight may be.
The law of Boyle referred to above is,
That the diminished pressure on the air is to atmospheric pressure as the
original volume of air is to its increased volume
original volume of air is to its increased volumo
P¹ P: V : V¹.
Thus assuming a diminished pressure of one pound per square inchi
14: 15 V: or an expansion of one fourteenth of the original volume
14
The action will be as follows,
The trap in the first instance being filled with fluid and the cylinder placed
over the egress pipe in the cistern, on raising the cylinder to the required height,
all the air expands and partially enters the cylinder, and beneath it a certain
quantity of fluid is raised, above the top of the egress pipe, and descends by its
own weight down the egress pipe whereby the weight in the egress pipe (the long
leg) quickly preponderates over the weight of fluid in the cylinder (or short leg),
and this flow continues so long as there is any liquid in the cistern, as the cylinder
quickly descends to the bottom of the cistern, owing to the weight of the column
of water in the egress pipe beneath it, thus becoming the short leg of the syphon.
The cylinder itself may be raised and lowered in any ordinary manner, sheaves,
weights or counterweights being used as required.
A short pipe starting from a point a fixed distance from the bottom of the
cistern and carried up to any desired point in the cylinder is introduced, in order
to prevent the force of water flow into the cistern from the ball cock starting the
syphonic action.
A collapsible bag the content of which is properly proportioned to the air
content of the syphon system, and expansion by Boyle's law, may be used instead
of the cylinder arrangement, it being attached to the egress tube and compressed
and allowed to expand.
What we have described here as a cylindrical arrangement may be of any other
form provided the prescribed conditions are observed.
Any suitable valve or trap of any other form may be used, either with or without
the trap bend described above.
Dated the 11th
1000
FRANCIS MONTAGUE SIMS.
FRANK TAYLOR HARROP.
JAMES HERBERT HARROP.
Improvements in Syphon Flushing Cisterns and Tanks for Water
Closets and for other Purposes.
We, FRANCIS MONTAGUE SIMS, late of 2, Smedley Lane, Cheetham Hill, Man-
chester, now of 850, Stockport Road, Manchester, Manufacturer, and FRANK

page_text: TAYLOR HARROP, Brassfounder, and JAMES HERBERT HARROP, Brassfounder, both
of the Firm of Messrs. Harrop Brothers & Co., 22, Bridge Street, Manchester, all
in the County of Lancaster, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention relates to improvements in the construction of syphon flushing
cisterns and tanks for water closets, and other purposes, and to meet the more
exacting demands of water companies who insist on the egress pipe being carried
not only above the overflow pipe of the cistern, but even over the top of the cistern
itself, and also that the only egress from the cistern for the fluid shall be over and
down said egress pipe, thus excluding any system requiring valves or other open-
ings in the bottom of the cistern.
We propose to achieve these desired results by appliances acting on pneumatic
principles, that is, the fluid is to be raised over the top of the egress pipe, by the
air acting directly on the surface of the liquid in the cistern without the assistance
of any appliances in the nature of force or lift pumps, or by scoops or buckets
raising the fluid mechanically.
In order that our invention may be clearly understood we have annexed hereto
a sheet of drawings illustrating the application thereof to a water closet cistern.
In Fig. 1A is a cistern fitted with ball cock and overflow pipe in the usual
manner; B is the egress pipe with its end above the top of the cistern, and C, D,
E, F, G, H (hereafter styled C H) is an arrangement of a special form partly
spherical, partly cylindrical. C D being the section over the top of the egress
pipe B as far as the height of the water level in the cistern A; D E F a spherical
enlargement and G H a section from the said enlargement to the bottom of the
cistern.
The whole of this arrangement CH is hereafter called the expansion chamber,
and is also the short leg of the syphon, and is placed over the part of the egress
pipe B, which is in and above the cistern A.
The said egress pipe B forms the long leg of the syphon and is of any required
length.
J is a water trap into which the egress pipe B dips a sufficient depth to seal
the end of it against the admission of air, and is of an area sufficient when the
egress pipe is dipped into it for the said fixed upon depth, to supply the amount
of liquid which will ascend up into the egress pipe B when the expansion cham-
ber CH is raised, without uncovering from fluid the lower end of said egress
pipe B.
L is a pipe from the water trap J to the closet, entering J at a point above the
level of the liquid in it when the system is at rest; or an equivalent of J may be
formed in the closet itself in which case the egress pipe B will drop vertically
and directly into it and the trap J will not be required.
The expansion chamber C H is made of the special shape or form described
above, first because we desire to have in the entire syphon system, as little air
as possible, and secondly, because it is necessary to appreciate, and reckon with
the expansion of air when it expands at a pressure less than that of the atmosphere,
and to calculate the amount of such expansion according to the mathematical work-
ing out of Boyle's law, as regards such expansion and also to provide for the
reception in the expansion chamber of such expanded volume of air in an area
the depth of which shall be as small as possible.
So, to reduce the quantity of air in the system we first cover the egress pipe B
from the water level in the cistern with the section of the expansion chamber C D,
of such greater area and height above the top of the egress pipe B, that the space
between CD and B, and between the top of B and the top of C H, shall be
sufficient only to allow a full and easy flow of the greatest volume of liquid the
egress pipe B is capable of carrying off.
Then the expansion chamber is extended as shewn by D, E, F to such extent

page_text: i.e., an increased volume of 4 cubic inches, and to this when the water trap J
is used has to be added the air in the bottom section of the egress pipe forced
upwards by the rise of liquid from the trap up the egress pipe, due to the fact
that on the expansion chamber being raised and the air in the egress pipe
rarefied to 14.75 lbs. the fluid in said trap will be raised in the egress pipe by
the external atmospheric pressure, until the weight of water supported by it is
such, as to equalize the pressure above and below the air in the syphon system.
Let us assume (for sake of illustration) the quantity of air so displaced to
be 8 cubic inches then we shall have an enlarged volume of air equal to 248 cubic
inches to deal with.
The action is as follows. The trap in the first instance being filled with fluid,
by pouring a little through the egress tube, and the expansion chamber C H being
placed in position over the egress pipe B in the cistern, on raising the expansion
chamber, all the air in the egress pipe and the part of the expansion chamber cover-
ing it as far as the water level inside it expands partly into the upper part of the
extended section of the expansion chamber, the remaining portion of which is
filled with water which is above the top of the egress pipe. The air pressure
above this water being 14.75 lbs. which is the same as that supporting it, the
water at the moment the raising of the expansion chamber ceases, is practically
unsupported, and tends to fall by virtue of its own weight down the egress pipe,
and when the weight of liquid in the egress pipe preponderates over the weight
in the expansion chamber, or short leg of the syphon, downward motion ensues
in the long leg, and the flow continues so long as there is any liquid in the cistern
as on the weight preponderating in the egress tube the expansion chamber itself
quickly descends to the bottom of the cistern, on account of the weight of the
column of liquid beneath it, thus acting as the short leg of the syphon.
It has been with these cisterns considered desirable to actuate them on what
is called the "pull and let go" system, i.e. the pull chain is not held down until
the flush is finished, with our invention to achieve this, it is requisite to get the
quickest and largest possible rush of water down the egress pipe so that the syphon
may be acting by virtue of the preponderating weight of liquid in the long leg
before the expansion chamber falling can depress the fluid in itself, and the cistern,
below the top of the egress pipe thus stopping the flow.
To facilitate this we use a small tube or funnel N as thin as possible and open
at both ends passing from the top of the section of the expansion chamber C Ĥ a

page_text: certain distance down the egress pipe B. The reason for it being, that when
the cylinder is quickly raised, the mouth of the egress pipe is as it were suddenly
plunged under water, and the air in the egress pipe is confined between the water
in the expansion chamber above it and in the trap J beneath it, causing hesitation
in the fluid falling down the egress pipe, the tendency of the air under pressure
on account of its great levity in comparison with water, being rather to rise
through the liquid then to be carried downwards by it, causing an actual conflict
between the air and water the small pipe allows the air to pass freely through and
behind the liquid, thus giving considerable easement, whereby the fall of fluid is
unchecked and it falls freely whilst the air in turn is readily carried out of the
syphon by the full force of the strongest flow.
On the cistern becoming empty, and the short leg uncovered by fluid, air enters
and fluid falls and re-covering again the end of the short leg stops the entry of
air, when the liquid will stand at a certain height in the expansion chamber, and
consequently at an equal height above the ordinary liquid level, in the trap J
in the bottom section of the long leg B of the syphon, the air between the two
columns of liquid being in a state of tension due to the weight of the liquid
column in the expansion chamber supported by atmospheric pressure.
On water entering the cistern from the ball cock and the level rising in the
cistern outside the expansion chamber the weight of water outside it counter-
balances the weight of water inside it, and consequently the density of the confined
air increases, and the water in the expansion chamber and in the bottom of the
egress pipe falls, until the levels outside and inside the expansion chamber are
equal, equality of pressure is established, motion ceases, and the liquid is at rest.
On again raising the expansion chamber the same action is repeated, it being a
physical impossibility whilst the system remains air tight to uncover the end
of the egress pipe from fluid the trap J having once been filled.
"
Although the pull and let go" is a favourite arrangement there are many closet
cisterns with which the pull chain has to be held down whilst the flush continues,
notably in the case of the single valve cisterns.
To prevent any confusion in the matter we propose to so adapt our system that
it shall be immaterial whether the pull is sustained or not, for which purpose we
fit beneath the bottom of the cistern, forming part of it a small well or cylinder K
greater in depth than the number of inches through which we have to raise the
expansion chamber, and in diameter sufficient to allow full and easy flow for
the greatest volume of water the egress pipe B can carry off, and into this cylinder
or wall, section G H of the expansion chamber is continued to such depth as
fixed on.
The action will then be as follows:-
On the expansion chamber being raised and duly let go, the action will be
precisely as before described, both cistern and well as far as the bottom of the
expansion chamber C H being emptied in the flush; but if the expansion chamber
is raised and held up, the flush will start in identically the same way and will
continue until the cistern, but not the well, has been emptied in the flush.
In either case no more than the regulated quantity of air can be expended.
A short pipe S may be fitted starting from a fixed point above the bottom of
the well of the cistern and carried up and into section C D of the expansion
chamber at any desired point to stop the action of the syphon before the short leg
is uncovered by fluid, on account of the cistern being emptied, or in some cases
to prevent the force of the water from the ball cock raising the level inside the
expansion chamber sufficiently to start the syphon and cause liquid to trickle
down the egress pipe.
An equivalent of the water trap J may if desired for convenience sake be placed
in the cylinder or well of the cistern as shewn at Fig. 2 whereby a portion only
and not the whole of the air in the syphon system is rarefied on raising the ex-
pansion chamber.
In this case the cylinder or well is made in two compartments, the lower end

page_text: of the expansion chamber terminating in the upper one K and a section of the egress
tube B passing airtight into and terminating in the lower compartment U in
precisely the same manner as into the water trap J of which as to area and depth
it is the counterpart, being fitted with a union P for the attachment of the rest
of the long leg B.
In this case also it is distinctly to be understood that whether the expansion
chamber is raised and let go or raised and held up, the flush is obtained precisely
as described above, as this forms a most important feature of our invention.
The expansion chamber may be raised and lowered in any customary manner,
sheaves, levers, weights, or counterweights, being used as desired.
Although we have here for the purpose of illustration described and shewn the
arrangement of the expansion chamber in a spherical and cylindrical form, it may
be of any other form, cylindrical or otherwise, provided the required conditions
as to extended and contracted sections are preserved.
Having now 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 is:
First The arrangement of the short leg of the syphon system in the form
described, and to act as an expansion chamber for the purpose hereinbefore set
forth.
"
Secondly: The provision of a trap at the end of the long leg of the syphon
either inside or outside the cistern whereby the whole of the air in the syphon
system must be attenuated for the purpose herein before set forth.
Thirdly. The provision in the expansion chamber and egress pipe of the air
escape pipe for the purpose set forth.
Fourthly. The use of the expansion chamber in combination with trap on the
egress pipe either inside or outside the cistern together with the air escape pipe,
for the purpose set forth.
Fifthly. The use of the small cylinder from the bottom of the cistern in com-
bination with the expansion chamber, trap on the egress pipe, either inside or
outside the cistern, and air escape pipe for the express purpose hereinbefore set
forth, viz. that whether the expansion chamber is raised and let go, or raised and
held up, a full and adequate flush over the top of the egress pipe and by no other
way is obtained. This being a special test of efficiency in our invention itself, as
also in comparison with any other system.
Sixthly. The small cylinder or well on the bottom of the cistern itself in two
compartments, the upper compartment forming a water trap for the end of the
expansion chamber or short leg of the syphon, and the lower compartment as a
trap for part of the longer leg of the syphon together with the union for rest of
the long leg of the syphon.
Seventhly. The employment of the expansion chamber and air escape pipe in
combination with the water traps in the small cylinder, in two compartments on
the bottom of the cistern, the same test of efficiency to be maintained as in Claim
six, i.e., an efficient flush whether the expansion chamber is held up or let go.
Dated this 8th day of December 1898.
FRANCIS MONTAGUE SIMS.
FRANK TAYLOR HARROP.
JAMES HERBERT HARROP.