Note: Descriptions are shown in the official language in which they were submitted.
CA 02557956 2007-05-30
File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
Title of the Invention
[0001] Dual Flush System for Toilet
Field of the Invention
[0002] The present invention generally relates to toilets flush systems.
Background of the Invention
[0003] The use of toilet flushing devices is known in the prior art. There is
a growing
consciousness of the need to conserve water, particularly in toilets where it
is not always
necessary to have a full flushing of the toilet. In order to conserve flushing
water,
attempts have been made at providing two flushing modes.
[0004] In conventional toilets, there is often provided in the water tank a
tank-ball or
flapper that can engage the annular seat formed by the flush pipe outlet. The
tank-ball is
linked by means of a lift chain to a lever pivotally mounted to the water tank
inner wall.
A flush actuator, usually a handle located outside the water tank controls the
lever. As
known in the art, upon the flush handle being pivoted from a rest position to
an operative
position, the lever will pull on the lift chain which in turn will raise the
tank-ball from its
seat to allow the water inside the water tank to flow into the toilet bowl. A
water supply
valve will allow water to be fed into the water tank until a float ball,
connected to the
supply valve, reaches a determined position in the water tank, at which point
the supply
valve will be closed. It is noted that the tank-ball is pivotally attached to
the base of the
overflow tube to pins, this simply as a matter of convenience since the
overflow pipe
extends closely adjacent to the flush pipe outlet. Also, the tank-ball is
slightly buoyant,
such that it will remain spaced from the flush pipe outlet while the water in
the water tank
flows out into the toilet bowl, but the combined action of the gravity and a
suction effect
from the flush pipe when the last water flows out through the flush pipe, will
bias the
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File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
tank-ball to engage its seat and seal the flush pipe outlet once the water
tank is empty, to
allow the water tank to be re-filled with water.
[0005] Indeed, toilets are conventionally made to allow a full flush to be
accomplished,
although this is not always necessary. Providing a selective dual flush system
as
contemplated by this invention would allow considerable water volumes to be
saved.
Objects of the Invention
[0006] Accordingly, a first object of the present invention is to provide a
dual flush
system for toilets allowing the user of the toilet to calibrate how much water
he/she
wishes to use when flushing the toilet.
[0007] Another object of the present invention is to provide a dual flush
system which
may be installed on existing toilets without modification of the latter.
[0008] A further object of the present invention is to provide a dual flush
system which is
inexpensive.
[0009] A still further object of the present invention is to provide a dual
flush system
which is easily installed without tools, and needs low maintenance.
[0010] Other and further objects and advantages of the present invention will
be obvious
upon an understanding of the illustrative embodiments about to be described or
will be
indicated in the appended claims, and various advantages not referred to
herein will occur
to one skilled in the art upon employment of the invention in practice.
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File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
Summary of the Invention
[0011] According to the present invention, there is provided a dual flush
system for a
toilet to allow a user to calibrate how much water he/she wishes to use when
flushing the
toilet. Either a partial flush if the flush handle is pivoted to its first
position or a full flush
if the flush handle is pivoted to its second position. Alternatively, two
different flush
handles could be provided, one for a partial flush and a second for a full
flush.
[0012] In use, if the toilet flush handle is pivoted from its rest position to
a first
predetermined position, the lever will in turn be pivoted and will pull
upwardly on lift
chain to raise the tank-ball from its seated to its lifted position, spacedly
over a flush pipe
extension and out of its sealed engagement with the flush pipe extension. This
will allow
water in the toilet water tank to flow through the coextensive flush pipe
extension and
flush pipe into the toilet bowl. However, it is understood that the entire
water tank would
not be emptied into the toilet bowl if only the tank-ball is raised by lift
chain, since the
height of flush pipe extension would prevent this from happening. More
specifically,
when tank-ball is raised from its seated to its lifted position while flush
pipe extension
remains in its lower position, water is allowed to drain from the toilet water
tank until it
reaches a level within the water tank which is equal to the position of the
second flush
outlet, which is higher than the first flush outlet.
[0013] Upon the flush handle being pivoted from its rest position to a second
predetermined position which is angularly beyond than its first predetermined
position,
the lever will in turn be pivoted further and will pull upwardly on lift chain
to first raise
the tank-ball from its seated to its lifted position and to further raise
flush pipe extension
from its lower to its upper position. More particularly, as the tank-ball is
gradually lifted
by lift chain, the tank-ball will first reach its lifted position and further
pulling on tank-
ball will raise the guiding part along overflow tube, effectively moving the
flush pipe
extension from its lower to its upper position. This will allow water in the
toilet water
tank to flow through the flush pipe into the toilet bowl.
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File number : 11133-002
Revision : Second Response
Date : 2007-12-21
[0014] Consequently, if the flush handle is only pivoted from its rest
position to its first
position, then the water tank will be partly drained into the toilet bowl,
since the water
level will only be allowed to lower until it reaches the second flush outlet.
However, if the
flush handle is pivoted from its rest to its second position, then the water
tank will be
entirely drained due to the flush pipe extension being raised to its upper
position spacedly
above the first flush outlet. With a double handle system, each handle is
connected to one
of the flush outlets.
[0015] It is noted that the dual flush system of the present invention can be
simply
retrofitted into a conventional toilet water tank. Indeed, to do so, the user
simply needs to
remove the existing tank-ball from a pair of pins provided at the lower
extremity of
overflow tube, and to which the tank-ball is conventionally releasably
attached. The
guiding part is then inserted along overflow tube, and the tank-ball is
pivotally installed
onto pins provided on the guiding part. Finally, the lift chain simply needs
to be shortened
to compensate for the height of the flush pipe extension. Alternately, a new
tank-ball
could be provided with the dual flush system, the former tank-ball being
disposed of.
[0016] Also, it is further noted that the presence of the downwardly
convergent alignment
arm allows the flush pipe extension to be self-centering and auto-aligning
with respect to
the flush pipe due to the sliding engagement of alignment arm along the flush
pipe if any
positional offset of the flush pipe extension was to occur while it moves away
or towards
the flush pipe. The alignment arm thus ensures that the flush pipe extension
bottom
opening will systematically come into a sealed engagement with the first flush
outlet
when the flush pipe extension is in its lower position. Furthermore, the
annular buoyant
member can be undersized on one side or even absent to fit to more toilets
models.
Because the distance between the wall of the water tank and the flush pipe may
vary, the
annular buoyant member can be thinner on the side of the wall of the water
tank fit to a
majority of toilets.
[0017] The dual flush system of the present invention also provides for the
tank-ball to
return to its seated position once a partial flush is completed. The same is
also provides
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File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
for the tank-ball to return to its seated position and for flush pipe
extension to return to its
lower position once a full flush is completed.
[0018] Indeed, while a partial flush is under way, the buoyant tank-ball will
float in the
water above the second flush outlet, thus remaining in its lifted position.
Once the water
level in the water tank reaches the position of the second flush outlet, the
tank-ball will
also reach the second flush outlet under the effect of gravity. The suction
effect of the
water flowing down into the toilet bowl will draw the tank-ball, now not being
countered
by its buoyancy, into a tight, sealed engagement against the second flush
outlet.
[0019] Likewise, while a full flush is under way, the buoyant tank-ball will
remain in its
lifted position until the water level reaches the position of the second flush
outlet. The
flush pipe extension will also remain in its raised position due to the
buoyant member
maintaining the flush pipe extension above the first flush outlet. While the
water level
first reach the level of the second flush outlet and continue to drain from
the water tank
between the raised flush pipe extension and the flush pipe, tank-ball will
return to its
seated position against the second flush outlet. Then, when the water level
reaches the
position of the first flush outlet, the flush pipe extension, not being
countered by its own
buoyancy, will engage the first flush outlet under the effect of gravity. The
suction effect
of the water flowing down into the toilet bowl will draw the tank-ball into a
tight, sealed
engagement against the second flush outlet, and with the flush pipe extension
thus
sealingly covered by the tank-ball, the flush pipe extension will also be
drawn into a tight,
sealed engagement against the first flush outlet.
[0020] The buoyancy of both the tank-ball and the buoyant member are just
sufficient to
counter the effect of gravity respectively on the tank-ball and the flush pipe
extension.
Thus, the tank-ball and flush pipe extension are not forced towards the water
line, but will
simply be maintained in a floating position when they are forced away from
their
respective seated and lower positions by the lift chain. The buoyancy is
provided by a
tight cavity enclosing air or any suitable buoyant material.
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CA 02557956 2007-05-30
File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
[0021] It is understood that the height of the flush pipe extension can be
chosen
according to the desired relative volume of water which is to be flushed with
a partial
flush.
[0022] The features of the present invention which are believed to be novel
are set forth
with particularity in the appended claims.
Brief Description of the Drawings
[0023] A preferred embodiment of the present invention will be described in
greater
detail below with reference to the following drawings, in which:
[0024] Figure 1 is a perspective view of the dual flush system installed in a
toilet.
[0025] Figure 2 is a perspective view of the dual flush system in accordance
with the
present invention.
[0026] Figure 3 to Figure 5 are side views of the dual flush system, showing
the device
in a closed, partially opened and completely opened condition, respectively.
[0027] Figure 6 is a cross side view of the dual flush system.
[0028] Figure 7 is a front view of the dual flush system.
[0029] Figure 8 is a cross side view of a first embodiment of the bottom
opening of the
dual flush system.
[0030] Figure 9 is a cross side view of a second embodiment of the bottom
opening of
the dual flush system.
[0031] Figure 10 is a top view showing the annular buoyant member.
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File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
Detailed Description of the Preferred Embodiment
[0032] Figure 2 shows the dual flush system for a toilet installed on a
conventional flush
pipe 20 having a first flush outlet 22 located inside the water tank (not
shown) of a
conventional toilet, near the bottom wall of the water tank. Flush pipe 20
leads towards
the toilet bowl (not shown), as known in the art, so as to allow water located
in the water
tank to selectively flow out of the tank and into the bowl through the flush
pipe 20.
[0033] Near flush pipe 20, there is conventionally provided an upright
overflow tube 30
having an overflow tube inlet 32. Overflow tube 30 merges with flush pipe 20
at the
bottom end of overflow tube 30 to convey water towards the toilet bowl if the
water level
in the water tank rises above the position of the overflow tube inlet 32.
[0034] Still in Figure 2, there is provided, according to the present
invention, a movable
guide part 50 that is more particularly mounted to and slidable along an
overflow tube 30,
as detailed hereinafter. Guiding part 50 carries a cylindrical, hollow flush
pipe extension
40 that is integrally attached to guiding part 50 by means of a rigid member
52. An
annular buoyant member 46 is carried by the flush pipe extension 40 wherein
the
buoyancy is provided with a tight cavity enclosing air or a buoyant material.
Flush pipe
extension 40 defines a second flush outlet 42 and a bottom opening 44,
respectively. The
bottom opening 44 is capable of sealed engagement with the first flush outlet
22 for
selectively forming therewith an extended flush pipe member within the toilet
water tank.
In other words, when flush pipe extension 40 operatively engages the flush
pipe 20, the
two pipes become coextensive. By means of the sliding engagement of guiding
part 50
along the overflow tube 30, flush pipe extension 40 is movable between a lower
position
shown in figures 3 and 4, in which its bottom opening 44 rests on and
sealingly engages
the first flush outlet 22. The upper position is shown in figures 2 and 5, in
which the flush
pipe extension 40 is located spacedly above flush pipe 20, and in which the
flush pipe
extension 40 clears the first flush outlet 22.
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File number : 11133-002
Revision : Replacement Pages
Date :2007-05-29
[0035] A tank-ball 60 is pivotally attached by means of a pair of pins 92 to
guiding part
50, near its upper end. The tank-ba1160 can move from a seated position shown
in figure
3, where it sealingly engages the second flush outlet 42 of flush pipe
extension 40 to
selectively close the access to flush pipe extension 40; to a lifted position
shown in
figures 2, 4 and 5, where it is lifted spacedly over the flush pipe extension
40 and it clears
the second flush outlet 42 to allow water to flow therethrough. A lift chain
62 is attached
at its bottom end to tank-ba1160 and to a lever (not shown) pivotally mounted
to the water
tank and controlled by a flush handle (not shown), similarly to prior art
devices.
[0036] A V-shaped alignment arm 48 is formed of two downwardly convergent rods
attached at their spaced-apart top ends to the flush pipe extension bottom
opening 44 and
attached to each other at their bottom ends. Alignment arm 48 projects
downwardly away
from the flush pipe extension 40. The bottom end of the alignment arm 48 is
destined to
extend within the flush pipe 20 in at least most positions of guiding part 50
along
overflow tube 30.
[0037] Figure 8 shows a first embodiment of the bottom opening 44 having
sealing
function provided with an angular section.
[0038] In Figure 9, another embodiment for the bottom opening 44 is shown,
wherein the
sealing function is provided by a sheet-like piece.
[0039] Figure 10 shows an embodiment of the annular buoyant member 46 which
has an
elliptical shape with a center line displaced from the center line of the
second flush outlet
42.
[0040] Although preferred embodiments of the invention have been described in
detail
herein and illustrated in the accompanying figures, it is to be understood
that the
invention is not limited to these precise embodiments and that various changes
and
modifications may be effected therein without departing from the scope or
spirit of the
present invention.
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