WO1996006990A1

WO1996006990A1 - A siphon flush device

Info

Publication number: WO1996006990A1
Application number: PCT/IE1995/000044
Authority: WO
Inventors: Colm James Costello
Original assignee: Epido Developments Limited
Priority date: 1994-09-01
Filing date: 1995-09-01
Publication date: 1996-03-07

Abstract

A siphon flush device (5) comprises a main liquid channel (2) having an inlet (3) and an outlet (4). The main channel (2) includes a network of interconnected channels or liquid paths (15, 16) leading from the inlet (3) to the outlet (4) for flow of liquid from a cistern (10) therethrough. The main channel (2) has a geometry which is adapted for the creation therein of a pressurised air lock preventing flow in the liquid path between the inlet (3) and outlet (4). A vent channel (11) connects the pressurized air lock to a zone of lower or ambient pressure, and a part of the vent channel (11) may be charged with liquid to prevent release of the pressurized air lock. The device includes a pilot siphon channel (8) communicating with the vent channel (11) and an actuator (20, 21) for raising the liquid level in the pilot channel (8), so that in use, a rise of liquid level in the pilot siphon channel (8) to a predetermined threshold results in siphonic liquid flow from the pilot siphon channel to a zone of lower or ambient pressure which results in discharge of liquid from the vent channel (11) which subsequently results in release of air from the pressurized air lock and results in liquid flow from the inlet (3) to the outlet (4) of the device.

Description

A SIPHON FLUSH DEVICE

The present invention relates to siphon flush devices and more particularly to toilet/urinal flushing siphon devices.

Known toilet flush mechanisms for emptying water from the cistern of a flush toilet comprise either a siphon flush mechanism or a plug mechanism.

In the known plug mechanism, the outlet from the cistern is sealed with a plug. The mechanism is operated by raising the plug allowing the water in the cistern to flow through the outlet and the cistern is thereby emptied.

A disadvantage associated with plug flush mechanisms is that any damage or wear to the rubber seal between the plug and the cistern outlet results in a continuous leakage of water from the cistern.

In a known siphon flush mechanism, a siphon conduit connects the contents of the cistern with the outlet at the base of the cistern. Flushing is achieved by lifting a volume of water, using a piston and one-way flap valve, to fill the siphon conduit and establish the siphonic action which then results in the cistern being emptied.

A disadvantage associated with this siphon mechanism is that a number of parts are required to construct the assembly including a siphon body, piston, one-way valve and return spring. The action of the piston and one way valve membrane can become unreliable after a period of use.

GB-A-2205595 discloses a prior art siphon flush device which operates on the basis of a sinuous liquid channel with a pressurised airlock. The airlock connects to a vent channel, the vent channel remaining blocked prior to actuation of the flush by a volume of water in a U-bend in the vent channel. Actuation is achieved by using a pulse of air to create an instability whereby the U-bend is blown clear of water by the pressurised air in the airlock. Such an actuation method is prone to malfunction, as the degree of instability created depends on the nature of the actuation air pulse provided by the user. An insufficient air pulse can cause partial release of air from the pressurised air lock without fully blowing the vent tube clear of water. In such conditions, the device may not adequately flood the outlet pipe with water and may not establish correct siphonic flush conditions.

The present invention seeks to alleviate the disadvantages associated with known devices for flushing toilets/urinals.

The present invention accordingly provides a siphon flush device comprising a main liquid channel having an inlet and an outlet, the main channel including a network of interconnected channels or liquid paths leading from the inlet to the outlet for flow of liquid from a cistern therethrough, the main channel having a geometry which is adapted for the creation therein of a pressurised air lock preventing flow in the liquid path between the inlet and outlet, a vent channel for connecting the pressurised air lock to a zone of lower or ambient pressure, and a means of charging part of the vent channel with liquid to prevent release of the pressurised air lock, characterised in that the device includes a pilot siphon channel communicating with the vent channel and means for raising the liquid level in the pilot channel, so that in use, a rise of liquid level in the pilot siphon channel to a predetermined threshold results in siphonic liquid flow from the pilot siphon channel to a zone of lower or ambient pressure which results in discharge of liquid from the vent channel which subsequently results in release of air from the pressurised air lock and results in liquid flow from the inlet to the outlet of the device.

Other features of the invention are recited in Claims 2 to 20, the contents of which are incorporated in this description by reference.

An advantage of the device in accordance with the present invention is that it has fewer parts, has greater reliability and can be produced at a lower manufacturing cost than known siphon type mechanisms. Versions of the flush toilet device in accordance with the present invention are available for automatic flushing of urinals and for manual flushing of WC's. The manual flush version has the added advantage of requiring less actuation force than known mechanisms and can be manufactured as a single flush or dual flush version.

It is a particular advantage of the present invention that malfunction of the siphonic flush effect can not be created by faulty actuation by a user. Once siphonic flow in the pilot siphon channel is established, the subsequent flushing action is predictable.

The invention will now be described more particularly with reference to the accompanying drawings in which are shown, by way of example only, a number of embodiments of a siphon flush device.

In the drawings,

Figure 1 is a plan view of a first embodiment of siphon device (omitting the actuation means shown in Figures 2, 3 and 4);

Figure 2 is a cross sectional side elevation of the first embodiment with the cistern full;

Figure 3 is a cross sectional side elevation of the first embodiment showing the actuation of the pilot siphon;

Figure 4 is a similar view to Figures 2 and 3 showing a flush commencing;

Figure 5 is a cross-sectional side view of a second embodiment of siphon device which is mounted in a separate cistern;

Figure 6 is a cross-sectional side view of a third embodiment of siphon device which is also mounted in a separate cistern;

Figure 7a and 7b are sectional views of an alternative embodiment of actuator means for actuating the flush in the siphon device; Figure 8 is a cross-sectional elevation of a fourth embodiment of siphon device;

Figure 9 is a cross-sectional elevation of a fifth embodiment of siphon device;

Figure 10 is a plan view of a sixth embodiment of siphon device; and

Figure 11 is a cross-sectional side view of the sixth embodiment.

Referring initially to Figures 1 to 4, the first embodiment of siphon device of the present invention is indicated generally by the reference numeral 1. The device of the first embodiment is for manually operated flushing of toilets. The device comprises a body having a labyrinthine network of chambers and channels including a main siphon channel 2, a vent channel 11, a vent channel inlet 5, a pilot siphon channel 8, a region 6, a bleed hole 7 to connect the region 6 to the cistern 10 and an inlet valve 35.

The main siphon channel 2 comprises four approximately vertical channel portions 15 joined by three approximate 180° bends 16. The bends may be in a nested configuration as shown in Figure 1 or alternatively may be in an open configuration as indicated in the third embodiment shown in Figure 5. The main siphon channel 2 includes an inlet 3 and an outlet 4, both of which are downwardly facing. The vent channel inlet 5 connects the main channel 2 to the region 6. The outlet 14 from the pilot siphon channel 8 allows the region 6 to empty when the water level in the pilot channel 8 reaches the top of the inverted U-bend 9.

The vent channel 11 links the vent channel inlet 5 to the outlet 4 from the main siphon channel 2 allowing air to flow through the outlet 4 when the water flow from the pilot siphon channel 8 causes the water level to lower sufficiently in the vent channel (11). The small bleed hole 7 in the blow moulded body provides liquid communication through a tortuous passage 25. The tortuous passage 25 slows the flow rate into the chamber 6 from the cistern 10. A buffer chamber 20 is located between an air pulse mechanism 21 and region 6. A small breather channel 23 connects the chamber 20 to the vent channel 11 and a conduit 22 connects the chamber 20 to the region 6.

A float operated relief valve 60 is mounted at the top of the cistern 10 and is activated in the event of overfilling of the cistern 10 by a faulty inlet valve 35 so as to disable the actuator 21 by opening an orifice in the actuator tube.

The operation of the flush device in the first embodiment will now be described with reference to Figures 2 to 4.

Referring initially to Figure 2, as the water level rises in the cistern 10, water enters the region 6 through the bleed hole 7 and tortuous passage 25. As the water level in the cistern 10 rises, the water also rises inside the pilot siphon channel 8, the buffer chamber 20, the vent channel 11 and the vent channel inlet 5. As the water level rises above the lower U-bend 13 of the vent channel 11, an airlock A is created in the main siphon channel 2. As the water level continues to rise, this air lock becomes pressurised.

As shown in Figures 3 and 4, when the air pulse mechanism 21 is actuated, the air enters the chamber 20 and forces water out through conduit 22 into the region 6, thereby increasing the water level in the pilot siphon channel 8. When the water level inside the pilot siphon channel 8 reaches the top of the inverted U-bend 9, the water flows rapidly to the pilot siphon channel outlet 14. Water is emptied from the region 6 faster than water can enter through the bleed hole 7. The dropping water level allows the pressurised air in the main channel 2 to be vented to the outlet 4 via the vent channel inlet 5 and vent channel 11. The direction of air flow is shown by the arrows indicated on Figure 4. The short column of water in the vent channel 11 is blown through by the expelled air. As shown in Figure 4, the water from the cistern 10 then floods the main channel 2 setting up the main siphon action to empty the cistern 10. The cistern stops emptying when air enters the main siphon channel 2 and breaks the siphon action,

The operator has the option of choosing a full or half flush. A half flush is achieved by allowing air to enter and break the siphon action via venting pipe outlet 40 when the cistern is approximately half empty. A full flush can be achieved by blocking the venting pipe inlet 41 with the actuator 21.

Referring now to Figure 5, the second embodiment of siphon device of the present invention is indicated generally by the reference numeral 101. The device of the second embodiment is for automatic flushing of urinals. The device comprises a body having a labyrinthine network of chambers and channels including a main siphon channel 102, a vent channel inlet 105, a pilot siphon channel 108, a region 106, a vent channel 111 and a bleed hole 107 to connect the region 106 to the cistern 110.

The main siphon channel 102 comprises four approximately vertical channel portions 115 joined by three 180° bends 116. The bends may be in the nested configuration shown or in an open configuration as indicated in the third embodiment shown in Figure 6. The main siphon channel 102 includes an inlet 103 and an outlet 104, both of which are downwardly facing.

The vent channel inlet 105 connects the main channel 102 to the region 106. The outlet 114 from the pilot siphon channel 108 allows the region 106 to empty when the water level in the pilot channel 108 reaches the top of the inverted U-bend 109.

The vent channel 111 links the vent channel inlet 105 to the outlet 104 from the main siphon channel 102 allowing air to flow through the outlet 104 when the water flow from the pilot siphon channel 108 causes the water level to lower sufficiently in the region 106. The small bleed hole 107 in the blow moulded body provides liquid communication between the region 106 and the cistern 110. The main siphon channel 2 has a tab 151 provided thereon which can be removed so as to provide for different flush levels. The operation of the flush device of the second embodiment will now be described. As the water level rises in the cistern 110, water enters the region 106 through the bleed hole 107. As the water level in the cistern 110 rises, the water also rises inside the pilot siphon channel 108, the vent channel 111 and the vent channel inlet 105. As the water level rises above the inlet 113 to the vent channel 111, an airlock B is created in the main siphon channel 102. As the water level continues to rise, this air lock becomes pressurised.

When the water level inside the pilot siphon channel 108 reaches the top of the inverted U-bend 109, the water flows rapidly to the pilot siphon channel outlet 114. Water is emptied from the region 106 faster than water can enter through the bleed hole 107. The dropping water level allows the pressurised air in the main channel 102 to be vented to the outlet 104 via the vent channel inlet 105 and vent channel 111. The short column of water in the vent channel 111 is blown through by the expelled air. The water from the cistern 110 then floods the main channel 102 setting up the main siphon action to empty the cistern 110. The cistern stops emptying when air enters the main siphon channel 2 and breaks the siphonic action.

A third embodiment of the siphon device is shown in Figures 6 and 7 and this third embodiment provides a manual flush version of the device.

The device of this embodiment comprises a blow moulded body 201 which includes the following channels; a main siphon channel 202, a vent channel inlet 205, a region 206, a pilot siphon channel 208, a vent channel 211, a priming chamber 220, and a small bleed hole 207 for connecting the region 206 to the cistern 210.

The main siphon channel 202 comprises four approximately vertical channel portions, joined by three 180° bends 216, with an inlet 203 and an outlet 204 both downwardly facing. The main siphon channel 202 may be in the open configuration as shown or alternatively may have the inverted U-bends in a nested configuration as in the first and second embodiments.

The vent channel inlet 205 connects the top of the first bend 216 to the region 206.

The pilot siphon channel 208 operates to empty the region 206 when the water level in the pilot siphon channel 208 reaches the top of the inverted U-bend 209.

The vent channel 211 has a priming chamber 220 including an actuation plunger 221 at its upper end, linking the vent channel inlet 205 to atmospheric air when the flow of liquid from the pilot siphon channel 208 causes the water level to lower sufficiently in the region 206. The small bleed hole 207 in the blow moulded body connects the region 206 to the cistern 210.

When the water level in the cistern 210 rises to its target level, the device is ready to be activated. The actuation plunger 221 is then depressed causing the water level in the priming chamber 220, in the vent channel inlet 205 and in the pilot siphon channel 208 to be raised. A siphon action commences in the pilot siphon channel 208 which causes the region 206 to be emptied faster than water can re-enter through the bleed hole 207. When the water level drops to the level of the inlet 213 to the vent channel 211, the pressurised air in the main siphon channel 202 exits through the vent channel inlet 205 and the vent channel 211, pushing any water in the vent channel 211 into the base of the priming chamber 220. The direction of air flow is shown by the direction of the arrows indicated in Figure 6. The main siphon channel 202 then floods and the cistern 210 empties until air enters the main siphon channel inlet 203 to break the siphonic action.

Referring now to Figure 9, in the fifth embodiment device 401, an actuation pulse channel 429 joins the pilot siphon 408 below the level of the bend 409. A pulse of air is provided by a push button or similar device and passes through the air pulse tube 430 and actuation pulse channel 429 so that a volume of air is injected into the pilot channel 408, thus forcing water in the pilot channel 408 over the bend 409 and setting up the pilot siphon action.

The sixth embodiment device 501 for use with automatic flushing of urinals is shown in Figures 10 and 11. It has a main siphon channel 502, vent channel inlet 505, a pilot siphon channel 508, a region 506, vent channel 511 and a bleed aperture 507 to connect the region to the cistern 510.

The main additional feature of the device 501 is a bypass channel 551 and bypass chamber 552 located between the vent channel 511 and the cistern 510. The chamber 552 is charged with a volume of water prior to flushing. During the flushing operation, the bypass channel 511 can vent air from an external conduit such as a sparge pipe by displacing water from the chamber 552 during the flush cycle.

The devices of the embodiments do not require close fitting moving parts and are not subject to wear or leaks.

The body of the devices can be produced cheaply and simply in a single piece using blow moulding technology.

Other embodiments of the device are described below:

a) Variations to the shape of the blow moulded body are possible without affecting the operating principle of the invention. The exact geometry of each channel is not critical provided the channels are designed to provide the correct flow conditions for reliable operation.

b) Various vent positions and configurations are possible for the dual flush version. c) Figure 8 shows an automatic flush version in which the region 305 is connected with a bleed channel 325 from the U-bend of the main siphon channel 302 instead of using a bleed hole to the water in the cistern. The principle of operation is not affected, except that the top of the pilot siphon channel bend 309 is at a lower level.

d) Variations in the vent channel cross section are desirable which ensure that the column of water in this channel blows away when the water level in the region reaches the bottom of this channel. In particular, the cross section may increase as the column of water travels upwards, thus shortening the column and reducing the air pressure required to blow it away.

e) The vent channel may vent to the air space above the cistern water level instead of to the outlet.

f) The outlet portion of the vent channel may be omitted and the pressurised air allowed to vent instead through the pilot siphon channel once the water in the region has emptied.

g) Various types of actuator may be used for the manual version shown in Figure 6. In one alternative shown in Figures 7(a) and 7(b), the actuator consists of a vessel 230, which when raised quickly from the position shown in Figure 7(a) to that shown in Figure 7(b), empties its contents into the priming chamber 231 to set off the pilot siphon.

It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the invention as defined in the appended claims.

Claims

O 96/06990 PCME95/00044- 1 1 -CLAIMS :

1. A siphon flush device (5) comprising a main liquid channel (2) having an inlet (3) and an outlet (4), the main channel (2) including a network of interconnected channels or liquid paths (15, 16) leading from the inlet (3) to the outlet (4) for flow of liquid from a cistern (10) therethrough, the main channel (2) having a geometry which is adapted for the creation therein of a pressurised air lock preventing flow in the liquid path between the inlet (3) and outlet (4), a vent channel (11) for connecting the pressurised air lock to a zone of lower or ambient pressure, and a means of charging part of the vent channel (11) with liquid to prevent release of the pressurised air lock, characterised in that the device includes a pilot siphon channel (8) communicating with the vent channel (11) and means (20, 21) for raising the liquid level in the pilot channel (8), so that in use, a rise of liquid level in the pilot siphon channel (8) to a predetermined threshold results in siphonic liquid flow from the pilot siphon channel to a zone of lower or ambient pressure which results in discharge of liquid from the vent channel (11) which subsequently results in release of air from the pressurised air lock and results in liquid flow from the inlet (3) to the outlet (4) of the device.

2. A siphon flush device as claimed in Claim 1, in which the pilot siphon channel (8) has an entrance opening from the vent channel at a first level, an inverted U-shaped apex (9) at a second level higher than the first level and an exit opening (14) at a third level lower than the first level, whereby while the liquid level is between the first and second levels, the air lock remains pressurised and when the liquid level is raised over the second level, liquid flow commences from the siphon and the air lock is released.

3. A siphon flush device as claimed in Claim 1 or Claim 2, in which the vent channel (11) and the pilot siphon channel (8) are separate and distinct channels, arranged so that release of liquid through the pilot siphon channel results in the release of pressurised air through the separate vent channel.

4. A siphon flush device as claimed in Claim 1 or Claim 2, in which the pilot siphon channel (8) acts as part of the vent channel (11).

5. A siphon flush device as claimed in any one of the preceding claims which includes an aperture (7) or interconnecting means to allow liquid to communicate with the vent channel (11) from the cistern (10), or the main channel (2), so as to allow liquid flow into the vent channel (11) to create a column of liquid which maintains the pressurised air lock.

6. A siphon flush device as claimed in any one of the preceding claims, in which the means for raising the liquid level in the pilot channel includes means for raising the level of liquid in the cistern to a predetermined threshold.

7. A siphon flush device as claimed in any one of Claims 1 to 5, including a plunger (221) movable within a complementary cavity (220) to raise the water level in the pilot siphon channel (8) to a predetermined threshold.

8. A siphon flush device as claimed in any one of Claims 1 to 5, including a vessel (230) for a quantity of liquid, the vessel (230) being movable upwardly to a pour position, so as to raise the level of water in the pilot siphon channel (208).

9. A siphon flush device as claimed in any one of Claims 1 to 5, in which the means for raising the liquid level in the pilot channel includes means (430) for introducing air directly into the pilot channel (408) to raise the level of liquid in the pilot siphon.

10. A siphon flush device as claimed in any one of Claims 1 to 5, in which the means for raising the liquid level in the pilot siphon channel (8) comprises a means for introducing a pulse of liquid into the pilot siphon.

11. A siphon flush device as claimed in Claim 10, in which the means for introducing a pulse of liquid includes a buffer chamber (20) provided between the means (21) for introducing air and the pilot siphon (8), the buffer chamber (20) being operable to contain sufficient liquid to be introduced into the pilot siphon by an increase in air pressure in the chamber (20), whereby in use when air is introduced into the buffer chamber (20) by the air introduction means (21) liquid is transferred to the pilot siphon (8) to raise the liquid level therein and cause activation of the pilot siphon.

12. A siphon flush device as claimed in Claims 9 to 11, including a plunger or bellows operable by a user to introduce air into the device.

13. A siphon flush device as claimed in any one of the preceding claims, which includes means for preventing the activation of the pilot siphon until the liquid level in the cistern has reached a sufficient level to establish siphonic flushing.

14. A siphon flush device as claimed in Claim 7, in which the travel of the plunger (221) can only displace enough water for the activation of the pilot siphon (208) when the liquid level in the cistern (210) has reached a sufficient level to establish siphonic flushing.

15. A siphon flush device as claimed in Claim 8, in which the vessel (230) is charged with enough liquid for the activation of the pilot siphon (208) when the liquid level in the cistern has reached a sufficient level to establish siphonic flushing.

16. A siphon flush device as claimed in Claim 9, in which sufficient liquid is contained above the air injection point for activation of the pilot siphon only when the liquid level in the cistern (410) has reached a sufficient level to establish siphonic flushing.

17. A siphon flush device as claimed in Claim 11, in which the buffer chamber contains a small breather channel (23), said channel (23) becoming blocked by liquid and permitting activation of the pilot siphon by injection of air only when the liquid level in the cistern has reached a sufficient level to establish siphonic flushing.

18. A siphon flush device as claimed in Claim 6, including a bypass channel (551) and chamber (552) located to connect the liquid conduit outlet (504) to a low level (507) in the cistern, such that the chamber (552) is charged with a volume of liquid prior to flushing and the bypass channel (551) can vent air from an external conduit by displacing liquid from the chamber (552) during the flush cycle.

19. A siphon flush device as claimed in any one of the preceding claims, including means (40) to vent and terminate the siphonic action so as to limit the volume of liquid released in a flushing action, whereby a user can determine whether to release the full or lesser volume of liquid available for flushing.

20. A siphon flush device as claimed in any one of the preceding claims, which is integrally moulded with a cistern (10).