Technical Field
[0001] The present invention relates to a siphonic flushing device. More particularly, the
present invention relates to a dual flush siphonic flushing device, as well as to
a toilet including such flushing device.
Background
[0002] Siphonic flushing devices have been available on the market for many years. Operating
on the general principle of a siphon, such flushing device generally consists of a
tubular bend being submerged into water enclosed within a water cistern.
[0003] For a siphon action of a flushing device having only one upper bend, water inside
the tube is normally mechanically forced upwards to start a flow of water through
the bend. However, as significant force is necessary for actually moving the required
quantity of water upwards double siphons have been suggested.
[0004] Double siphons include a tube being bent to form an M-shape. Hence, a water trap
is formed between the inlet and the outlet such that air may be compressed between
the inlet and the water trap.
[0005] Prior to flushing, i.e. in the phase of filling the cistern with water compressed
air will be entrapped within the first bend, thus being arranged at the highest vertical
position of the tube and preventing water from flowing through the bend.
[0006] Upon flushing the air is allowed to escape through a vent valve whereby the water
inside the tube is allowed to flow over the bend and further into the WC bowl. As
the outlet is arranged vertically below the inlet, i.e. the open tubular end arranged
within the cistern, the siphon will draw water from the cistern until the water level
of the cistern is below the inlet.
[0007] After flushing an inlet valve will open for refilling the cistern. As the water level
of the cistern rises, water will also start to fill the tube of the flushing device.
As the vent valve is now closed, air will be compressed within the bend. Filling of
water is finished when a specific water level is reached, whereby a subsequent flushing
sequence may again be initiated.
[0008] A siphonic flushing device provides a number of advantages compared to other flushing
devices since there is no need for a moveable outlet valve. However, different solutions
on the market still have some major drawbacks, especially when it comes to siphonic
flushing devices having dual-flush capabilities, i.e. configurations allowing for
small and large volume flushes.
[0009] For example,
EP1640515 describes a double flush siphon flushing system. Similarly to the general description
above, a vent valve allows compressed air to escape whereby the flushing sequence
is performed. By providing two different push buttons corresponding to large or small
flush volume, venting is controlled such that different volumes of water are discharged.
Hence, this system provides a dual flush functionality. However, a number of disadvantages
are associated with this kind of solution. As an example, it does not allow the flush
volumes to be easily changed. A cistern divider is provided for changing the large
volume flush from 6 liters to 9 liters; however no adjustment between these values
is possible. Hence, this particular solution may not fit different markets having
different standards for flushing volumes.
[0010] It would therefore be advantageous to provide a more versatile flushing device which
allows for easy adjustment of the flushing volume in order to fit various needs on
the market.
Summary
[0011] The present invention seeks to mitigate or eliminate the above-identified deficiencies
and solves at least the above mentioned problems by providing a siphonic flushing
device with a dual flush functionality.
[0012] An idea of the present invention is to provide a siphonic flushing device having
an air intake device in connection with the siphon tube such that air intake may be
controlled for terminating the flushing sequence at a specific flushing volume.
[0013] According to a first aspect, a siphonic flushing device is provided. The flushing
device comprises a tube extending from an open inlet end to an open outlet end via
a bend, arranged above said inlet end and said outlet end, as well as via a water
trap formed between said bend and said outlet end , and wherein said outlet end is
arranged vertically below said inlet end; and a venting device connected to said bend
for allowing air entrapped within said bend to escape; wherein said flushing device
further comprises an air intake device having an air outlet connected to said tube
for allowing air to enter said tube, wherein said air intake device further comprises
a first air inlet arranged vertically below said air outlet.
[0014] According to another aspect, a siphonic dual flushing device is provided. The device
comprises a tube extending from an open inlet end to an open outlet end via a bend,
arranged above said inlet end and said outlet end, as well as via a water trap formed
between said bend and said outlet end, and wherein said outlet end is arranged below
said inlet end; and an air intake device having an air outlet connected to said tube
for allowing air to enter said tube for terminating an ongoing flush, wherein said
air intake device further comprises a first air inlet arranged vertically below said
air outlet, and a second air inlet arranged vertically below said first air inlet,
and wherein a first flush volume is provided if air is introduced through the first
inlet, and a second flush volume is provided if air is introduced through the second
inlet.
[0015] The air outlet of said air intake device may preferably be connected to said bend.
Inside the tube, a sub-pressure will be present during flushing due to the flow of
water. Since air is introduced in the air inlet as the water level within the cistern
lowers, flushing will always be terminated as air will be drawn into the bend due
to the sub-pressure.
[0016] The first air inlet of said air intake device may comprise a float valve being moveable
in a vertical direction, which is advantageous in that the air inlet will open as
soon as the water lever inside the cistern lowers to a predetermined level, set by
the float valve.
[0017] The air intake device may comprise a second air inlet arranged below said first air
inlet. Hence, the volume of a large flush may be controlled such that a large volume
flush not necessarily must correspond to the water level inside the cistern being
lowered below the tube inlet end. Further, by terminating a large volume flush by
introducing air into the bend via the second air inlet, undesired sound, such as bubbling
noise is reduced. This is due to the fact that the second air inlet, having a diameter
substantially less than the diameter of the tube inlet, will provide smaller air bubbles
entering the tube at a higher level.
[0018] The second air inlet may comprise an open conduit end having an oblique cut. This
further decreases unwanted noise associated with introducing air into the tube.
[0019] The vertical position of said air intake device may be adjustable relative the tube,
which is advantageous in that the volumes corresponding to large and small flushes
may be easily adjusted.
[0020] A first flushing volume may thus be achieved when the first air inlet is opened,
and a second flushing volume being larger than the first flushing volume may thus
be achieved when the first air inlet is locked in a closed position such that air
is introduced via the second air inlet.
[0021] The venting device may be connected to flush initiating means such that said venting
device opens when a user operates said flush initiating means. Hence, immediate flushing
is provided as soon as the user requests such action.
[0022] The flush initiating means may preferably comprise two different push buttons, or
rocker buttons or lift buttons, mechanically connected to said venting device.
[0023] The flush initiating means may be mechanically connected to said air intake device,
which is advantageous in that the choice of push button may control activation of
the first air inlet.
[0024] The first air inlet of the second venting device may be locked in a closed position
when a user initiates a flushing sequence of a first volume, such that flushing is
terminated when the water level outside the tube is below the vertical lever of the
second air inlet of the air intake device.
[0025] Further, the first air inlet of the second venting device may be released from said
closed position when a user initiates a flushing sequence of a second volume being
smaller than said first volume, such that flushing is terminated when the water level
outside the tube is below the vertical lever of the first air inlet of the air intake
device.
[0026] According to a second aspect, a water cistern is provided enclosing a siphonic flushing
device according to the first aspect.
[0027] According to a third aspect a WC suite is provided comprising a water cistern according
to the second aspect.
Brief Description of Drawings
[0028] These and other aspects, features and advantages of which the invention is capable
of will be apparent and elucidated from the following description of embodiments of
the present invention, reference being made to the accompanying drawings, in which
Fig. 1 is an isometric view of a siphonic flushing device according to an embodiment;
Fig. 2a is side view of the flushing device shown in Fig.1 in an idle mode;
Fig. 2b is a cross-sectional view of a venting device in a closed position;
Fig. 2c is a cross-sectional view of the venting device in an open position;
Fig. 3a is a cross-sectional view of a flushing device prior to initiating a flush
sequence;
Fig. 3b is a view of the flushing device of Fig. 3a upon initiating a large volume
flush sequence;
Fig. 3c is a side view of an air intake device of the flushing device;
Fig. 4 is a side view of the flushing device of Fig. 3a upon initiating a small volume
flush sequence; and
Fig. 5a-b are side views of the flushing device of Fig. 4 after a small volume flushing
water is discharged.
Detailed Description
[0029] In the following, embodiments of a siphonic flushing device 100 will be described.
Starting with Fig. 1 the flushing device 100 generally includes a hollow tube 110,
a venting device 200, as well as an air intake device 300. Additional components preferred
for a proper functionality includes a flush initiating means 120 and a support structure
130 for fixation of the flush initiating means 120 and possibly also an inlet valve.
[0030] The entire flushing device 100 is intended to be arranged inside a water cistern,
such that water enclosed in the cistern may be flushed into an associated toilet bowl
by means of the flushing device 100.
[0031] The hollow tube 110 forms a water conduit extending from an open inlet 112 to an
open outlet 114. The tube 110 extends vertically upwards from the inlet 112 to a bend
116 from which the tube 110 extends downwards to a second bend forming a water trap
118. Hence, the tube 110 has an M-shape. However, in order to reduce the lateral extension
the tube 110 is preferably twisted around the vertical axis as is shown in Fig. 1.
[0032] Preferably, the tube 110 is manufactured as two or more parts which may be easily
connected by a snap-lock, threads, or similar. Further, ribs 119 may be provided for
increasing the stability of the tube 110 and arranged to connect different portions
of the outer surface of the tube 110. However the tube 110 may also be manufactured
by welding two or more parts together or it may be formed as one part by means of
blow molding technology.
[0033] As the siphonic tube 110 is configured to draw flushing water from the inlet 112
to the outlet 114, the outlet 114 is connected to an inlet port of a WC bowl (not
shown). The outlet 114 is arranged vertically below the inlet 112.
[0034] The flushing device 100 is configured to be arranged within a water cistern (not
shown), e.g. a separate cistern, on a WC suite, or enclosed within the back rest of
a WC bowl or enclosed within a wall supporting a wall hung WC. For securely fastening
the flushing device in the cistern the support structure 130 has portions 132 for
engagement with corresponding fastening portions of the cistern. The flushing device
100 is aligned within the cistern such that the outlet 114 of the tube connects with
inlet port to the WC bowl. In such position, the inlet 112 of the tube 110 is arranged
at a certain vertical distance from the bottom of the cistern such that water present
in the cistern may flow through the inlet 112.
[0035] Before turning into details of the flush initiating means 120, the venting device
200, and the air intake device 300, some details of the general functionality will
be given.
[0036] Before a flush, water is enclosed within the cistern up to a predefined level. As
the inlet 112 of the tube 110 is always open water will also have entered the tube
110 up to the same level. The predefined water level, corresponding to a full cistern,
is arranged above the bend 116. Hence, a small volume of water may flow into the water
trap 118 until the pressure of the compressed air is preventing water to flow over
the bend 116. The water trap 118 also accommodates water from a prior flush, such
that air is entrapped between the bend 116 and the water trap 118. Since the water
within the tube 110 (i.e. water coming from the inlet 112) has forced the air within
the tube 110 to move towards the bend and the water trap 118, this air is compressed.
[0037] A venting device 200 is configured to release the air entrapped within the bend 116
such that the pressure is reduced, whereby cistern water will start to flow into the
tube 110 and over the bend 116, into the water trap 118, and subsequently out trough
the outlet 114.
[0038] Flushing is aborted when the water level in the cistern is below the inlet 112 of
the tube 110, or when air is again introduced into the tube 110. Upon this, an inlet
valve will open whereby the cistern is again filled with water returning the flushing
system to a state where it is ready to begin flushing.
[0039] Now turning to particular embodiments of a siphonic flushing device, a venting device
200 is preferably mechanically linked to the flush initiating means 120. The flush
initiating means 120 may e.g. include two push buttons 121a, 121b, which when pressed
down provides a small volume flush or a large volume flush, respectively. It should
however be appreciated that the push buttons may be replaced by rocker buttons or
lift buttons, providing the same functionality of activating flushing sequences of
different water volumes.
[0040] When one of the buttons 121a, 121b is pressed down a tilting of a lever construction
122 will cause a release action on the venting device 200 such that it opens, thus
allowing air compressed within the bend 116 to escape. Releasing the air will thus
create a sub-pressure within the tube 110 which will draw water from the inlet 112,
over the bend 116, and out through the outlet 114. That is, releasing air will start
flushing.
[0041] Correspondingly, when the buttons are resting in their idle position (i.e. not being
pressed down) the lever construction 122 locks the venting device 200 in a closed
position thus preventing it from open and from releasing entrapped air.
[0042] The push buttons 121a, 121b are preferably accessible from the outside of the water
cistern such that they are readily available for a user.
[0043] Turning now to Figs. 2a-c, side views and cross sectional views of the venting device
200 are shown. As can be seen in Fig. 2a the venting device is arranged at the bend
116 and includes a fluid connection 202 at the highest position of the tube 110. The
fluid connection 202 extends upwards as a hollow conduit 204 which is surrounded by
a hollow housing 206 being sealed against the outer surface of the tube 110. The hollow
housing 206 forms an annular volume 207 delimited by the hollow conduit 204. During
cistern filling, this annular volume 207 is at least partly filled with water.
[0044] The hollow conduit 204 has an open upper end 208 which may be sealed against a piston
210 being moveable and engagable by a respective motion of the lever construction
122. The piston, having a cylindrical shape with a closed upper end, extends into
the water of the annular volume 207 thus forming a water trap preventing air inside
the tube 110 to escape.
[0045] That is, when a user uses the flush initiating means 120 for starting a flush the
piston 210 will move in a vertically linear manner as will be further described below.
[0046] Turning now to Fig. 2b, a zoomed-in view of the venting device 200 is shown. In this
position, there is no movement of the push buttons 121a, 121b such that the venting
device 200 is closed. As is clearly seen, the piston 210 is thus pressed down such
that the sidewall of the piston 210 extends into the water of the annular volume 207.
Air inside the bend 116 may thus not escape, whereby flushing is prevented. However,
as soon as a user presses any one of the push buttons 121a, 121b, the lever construction
122 will unlock the piston 210 whereby the compressed air will be able to force the
piston 210 upwards to allow escape. This is shown in Fig. 2c, where the piston 210
is raised by the air pressure inside the bend 116 such that the sidewall of the piston
210 no longer extends into the water of the annular volume 207. The lever construction
122 is preferably spring biased towards it idle position such that the piston 210
will automatically return to the position where the piston 210 is submerged into the
water of the annular volume 207 and blocked from moving upwards. Hence, the piston
210 forms an open-ended cylinder.
[0047] In accordance with the description so far the venting device 200 provides a mechanical
connection between the flush initiating means 120 and the tube 110, such that upon
initiating a flush, the venting device 200 unlocks the piston 210 whereby the compressed
air inside the bend 116 is allowed to escape, thereby starting the flushing. The venting
device 200 operates in the same manner independently of a large or small flush.
[0048] Now turning to Figs. 3a-c, details of the air intake device 300 will be discussed.
The air intake device 300 is arranged outside the tube 110 and has an air outlet connected
to the tube 110 at the bend 116 at a position close to the venting device connection
202 (shown in Fig. 2a). The air intake device 300 is connected to the tube 110 via
a flexible hose 302 (see e.g. Fig. 5b) such that the vertical position of the air
intake device 300 relative the tube 110 may be easily adjusted. Further, some sort
of fastener, such as a guiding rod, may be provided along the outer surface of the
tube 110 to which the air intake device 300 may be attached at different vertical
positions. The air intake device 300 includes two separate air inlets 304, 306 arranged
at different vertical positions. The air inlets 304, 306 are provided such that the
first inlet 304 will be opened when a small volume flush is initiated, whereby the
second air inlet 306 is operational when a large volume flush is initiated.
[0049] In Fig. 3a, the air intake device 300 is shown where a large volume flush is activated.
When the corresponding push button 121a is pressed down a mechanical link 310 connected
to the lever construction 122 will cause a mechanical locking action on the air intake
device, as shown in Fig. 3c. Hence, a float valve 320 (also shown in Fig. 3c) associated
with the first air inlet 304 will be locked in its position thus keeping the first
air inlet 304 closed. The locking action may preferably be provided by a protrusion
on the air intake device 300 being engagable with a recess of the mechanical link
310 such that when the mechanical link 310 is in a first position, the recess prevents
the float 320 of the air intake device 300 from moving downwards. Correspondingly,
when the mechanical link 310 moves corresponding to a small volume flush, the recess
will no longer engage the protrusion of the air intake device such that the float
320 of the air intake device 300 is free to move downwards. As the flushing proceeds
the water level inside the cistern will lower until it goes below the vertical position
of the second air inlet 306. Hence, air will be allowed to flow into the bend 116
whereby flushing is terminated.
[0050] From above it is clear that the air intake device 300 operates by allowing or preventing
a float 320 from moving with the water level inside the cistern. When a large volume
flush is initiated the float 320 is locked in an upright position whereby the upper
air inlet 304 is closed. Even when the water level inside the cistern lowers during
flushing, the float 320 will remain in its upper position thus keeping the air inlet
304 closed. On the other hand, when a small volume flush is initiated the float will
no longer be locked due to a different movement of the mechanical link 310 (please
note that the venting device 200 is always actuated independently of large or small
volume flush initiation). When the water level lowers the float 320 will move correspondingly,
thus exposing the air inlet 304 when the water level is below the vertical position
of the air inlet 304.
[0051] Now turning to Fig. 4, the flushing device 100 is shown wherein a small volume flush
is initiated. When a user presses the corresponding push button 121b, the mechanical
link 310 will release the float valve 320 of the air intake device 300 at the same
time as the venting device 200 is maneuvered, i.e. when the flush starts. Hence, when
the water level of the cistern drops, the float valve 320 will also move downwards.
Turning to Figs. 5a and 5b, the movement of the float valve 320 will open the first
air inlet 304 such that air will be allowed to enter the bend 116 for terminating
the flushing sequence.
[0052] As is readily understood, during flushing there will be no or very little air inside
the tube 110 since the air has escaped during initiating the flush. However, once
air is allowed to enter the tube 110 at the position of the bend 116, flushing will
be terminated since the suction force will dra air instead of water into the bend
116. Large and small volume flush is thus controlled by setting the water level at
which the air intake device 300 introduces air into the tube 110, i.e. the water level
of the cistern in which the tube 110 is arranged.
[0053] The float valve 320 may include a floating body 322 being slidable on a vertical
venting tube 324. The floating body 322, which is released upon initiating a small
volume flush, will move downwards along with the water level during flushing due to
gravity. As the floating body 322 lowers, it will eventually allow air to enter the
vertical venting tube 324 (see Fig. 5b). For this, a valve seat 326 is provided on
the upper part of the vertical venting tube 324 adjacent to and connected to the flexible
hose 302. The valve seat 326 has tapered surfaces 328 engagable with corresponding
tapered surfaces 330 on the inner side of the floating body 322. A small slit, preferably
annular, is provided between the vertical venting tube 324 and the valve seat 326
for allowing air flow into the valve seat 326, as indicated by the arrow in Fig. 5b.
Hence, flushing will be terminated as air is allowed to enter the vertical venting
tube 324 and escapes upwards into the bend 116 via the valve seat 326 and the flexible
hose 302. When the water level in the cistern is raised upon filling, the floating
body 322 will move upwards and again seal the holes in the vertical tube 324.
[0054] The second air inlet 306 may preferably be provided with an oblique cut, which has
been proven to reduce undesired sound when air is introduced for terminating the flushing
sequence. As previously described, reduced diameter of the air intake pipe will reduce
the size of air bubbles thus reducing the generated sound. The second air inlet 306
is operational only when the float 320 is locked, i.e. when initiating a large volume
flush.
[0055] The air intake device 300 thus provides a highly advantageous construction for allowing
two different volumes of flushing. The floating body 322 is locked or unlocked depending
on the last flush initiating being either one of the buttons 121a, 121b, A new flush
initiation will directly cause a corresponding action on the floating body, i.e. causing
it to be locked or unlocked.
[0056] The present invention has been described above with reference to specific embodiments.
However, other embodiments are equally possible within the scope of the invention.
The invention is thus only limited by the appended claims.
[0057] It is also to be understood that the present invention may be used for WC bowls suspended
from a wall structure as well as WC bowls securely attached to the floor; or separate
flushing cisterns arranged inside or outside a wall. Vertical flushing buttons providing
mechanical activation of the flushing will only requiring minor modifications for
connecting the manual flush buttons with the venting device and the air intake device.
Further, all references to "upper", "lower", "above", "below", "upwards, downwards",
or similar should be interpreted as a position during normal use, i.e. when the flushing
device is mounted in a water cistern.
1. A siphonic dual flushing device, comprising
a tube (110) extending from an open inlet end (112) to an open outlet end (114) via
a bend (116), arranged above said inlet end (112) and said outlet end (114), as well
as via a water trap (118) formed between said bend (116) and said outlet end (114),
and wherein said outlet end (114) is arranged below said inlet end (112); and
an air intake device (300) having an air outlet connected to said tube (110) for allowing
air to enter said tube (110) for terminating an ongoing flush, wherein said air intake
device (300) further comprises a first air inlet (304) arranged vertically below said
air outlet, and a second air inlet (306) arranged vertically below said first air
inlet (304), and wherein a first flush volume is provided if air is introduced through
the first inlet (304), and a second flush volume is provided if air is introduced
through the second inlet (306).
2. The siphonic flushing device according to claim 1, wherein the air outlet of said
air intake device (300) is connected to said bend (116).
3. The siphonic flushing device according to claim 1 or 2, wherein said first air inlet
(304) of said air intake device (300) comprises a float valve being moveable in a
vertical direction.
4. The siphonic flushing device according to any one of the preceding claims, further
comprising a venting device (200) connected to said bend (116) for allowing air entrapped
within said bend (116) to escape for initiating a flush.
5. The siphonic flushing device according to any one of the preceding claims, wherein
said second air inlet (306) comprises an open conduit end having an oblique cut.
6. The siphonic flushing device according to any one of the preceding claims, wherein
the tube (110) comprises a support to which the air intake device (300) is connected
such that the vertical position of said air intake device (300) is adjustable relative
the tube (110).
7. The siphonic flushing device according to any one of the preceding claims, wherein
a first flushing volume is achieved when the first air inlet (304) is opened thus
allowing air to flow into the tube (110), and a second flushing volume being larger
than the first flushing volume is achieved when the first air inlet (304) is locked
in a closed position such that air is introduced via the second air inlet (306) thus
allowing air to flow into the tube (110).
8. The siphonic flushing device according to any one of the preceding claims, wherein
said venting device (200) is connected to flush initiating means (120) such that a
piston (210) of said venting device (200) is unlocked and allowed to open when a user
operates said flush initiating means (120).
9. The siphonic flushing device according to claim 8, wherein said flush initiating means
(120) comprises two different push buttons (121a, 121b) mechanically connected to
the piston (210) of said venting device (200).
10. The siphonic flushing device according to claim 8 or 9, wherein said flush initiating
means (120) is mechanically connected to said air intake device (300).
11. The siphonic flushing device according to claim 4, wherein said first air inlet (304)
of the air intake device (300) is configured to be locked in a closed position when
a user initiates a flushing sequence of a first volume, such that flushing is terminated
when the water level outside the tube (110) is below the vertical level of the second
air inlet (306) of the air intake device (300) whereby air is allowed to flow into
the tube (110).
12. The siphonic flushing device according to claim 11, wherein said first air inlet (304)
of the air intake device (300) is configured to be released from said closed position
when a user initiates a flushing sequence of a second volume being smaller than said
first volume, such that flushing is terminated when the water level outside the tube
(110) is below the vertical level of the first air inlet (304) of the air intake device
(300) whereby air is allowed to flow into the tube (110).
13. A water cistern, enclosing a siphonic flushing device according to any one the preceding
claims.
14. A WC suite, comprising a water cistern according to claim 13.