EP0679210B1

EP0679210B1 - A water closet device

Info

Publication number: EP0679210B1
Application number: EP94919958A
Authority: EP
Inventors: Per BORNHÖFT
Original assignee: San Aqua Euro AB
Current assignee: San Aqua Euro AB
Priority date: 1993-06-22
Filing date: 1994-06-22
Publication date: 1998-12-09
Anticipated expiration: 2014-06-22
Also published as: WO1995000720A1; EP0679210A1; SE501293C2; AU7089994A; DE69415146D1; ATE174396T1; SE9302154D0; DE69415146T2; SE9302154L

Abstract

The present invention concerns an arrangement for flushing toilets with flushing systems for water-saving flushing with the aid of recirculating discharge water and comprising at least one toilet with a toilet bowl (2) which presents a discharge outlet (4) at its lower end and a closure arrangement (8) for the discharge outlet. An upper flushing system with inlet for water to the toilet bowl is arranged for flushing discharged material down to the discharge outlet, whereby a discharge conduit (5) leads from the discharge outlet (4) of the toilet bowl at the closure arrangement to a discharge tank (7). A lower flushing system with inlet (11, 12) for recirculating discharge water is arranged to recirculate discharge water from the discharge tank. Said inlet (11, 12) for the recirculated discharge water is positioned below the closure arrangement (8), and is directed substantially from the closure arrangement, so that when the discharge water is injected through said inlet under pressure, an underpressure is created below the closure arrangement in order that, after opening this, the transport of the discharged material will be furthered in a direction from the toilet bowl.

Description

The present invention concerns an arrangement for flushing toilets according to the preamble of claim 1 (see for instance document US-A-3,611,447).

The present type of flushing toilets relate to flushing systems for low-consumption toilet flushing with the aid of recirculating discharge water. Such flushing systems are already known in connection with transportation, such as in aeroplanes, where the discharge water is recirculated back to the toilet bowl, or more accurately above the flap which closes the lower end of the bowl during use of the toilet bowl before flushing. Due to this, a large amount of disinfection fluid must be added since the discharge water for each flushing becomes more and more polluted. Upon recirculation back to the toilet bowl, the recirculated water cannot be given a sufficient force to achieve a satisfactory transport of the discharged products.

The object of the present invention is to achieve an arrangement which ensures an effective flushing with minimal risk of clogging in the system.

Said object is achieved by means of an arrangement according to the present invention, the features of which are defined in claim 1.

The invention will now be described in more detail with respect to an embodiment and to the accompanying drawings, in which:

Fig. 1: schematically shows a complete flushing system which makes use of the arrangement according to the invention whilst
Fig. 2: schematically shows a longitudinal cross-section through a portion of the arrangement according to the invention.

As is clear from Fig. 1, the arrangement according to the invention consists of at least one toilet 1 with a toilet bowl 2 supporting a toilet seat 3 at the upper end, said toilet seat normally being provided with a cover. The toilet bowl presents a discharge outlet 4 at the bottom which leads to a discharge conduit 5 connected to a discharge tank 7 at its far end 6.

As best shown in Fig. 2, a closure arrangement 8 in the form of a flap is arranged at the lower end 4 of the toilet, said flap being movable between a closed position as shown in Fig. 2, shutting the discharge outlet 4 from communication downwardly towards the discharge conduit 5, and an open position in which the discharge outlet 4 is opened to as large an extent as possible for release of discharge water and discharged products. In the shown embodiment the flap is pivotally supported around an axis 9 and adjustable between its positions by means of a manoeuvring device 10 which in the shown example is constituted by a pneumatic cylinder. The manoeuvring device 10 may also be assisted in being biased towards the closed position by means of a spring mechanism (not shown) which pre-loads the flap 8 in the direction of closure.

In accordance with the invention one or more (in the shown example two)

inlet parts

11, 12 for recirculation of the flushing water are arranged in the discharge conduit after the discharge outlet of the toilet bowl and below the closure arrangement 8. In the simplest case the inlets can be formed as openings in the wall of the discharge conduit and directed substantially downwardly. In the shown embodiment the inlets are formed as flushing nozzles or pipe connectors which, with a portion 13, project partially into a widened portion 14 of the discharge tube. In the shown embodiment, the widened part is formed as a container which is substantially conical, or at least tapering, in a downward direction with a step-like, collar-formed projection 15 into which the

inlets

10, 11, 12 are arranged with their central axis 16 at an acute angle to the main longitudinal axis 17 of the discharge outlet.

The flushing system is provided with a return conduit 18 (see Fig. 1) for said recirculation of the discharge water, said conduit at one end 19 being connected to the discharge tank 7 and, at its other end 20, branched to the

inlets

11, 12. The discharge tank 7 is provided with a filter 20 which separates a part 21, to which the discharge conduit 5 is connected, and a part 22, from which the return conduit 18 leaves. As is shown in Fig. 1, the orifice 6 of the discharge conduit 5 is directed towards the filter 20 for rinsing this so that clogging is counteracted. The solid particles mainly stay in part 21 whilst part 22 is free of solid particles to the highest possible degree. A pump 23 is arranged in the return conduit 18, said pump dividing the return conduit 18 into a suction conduit 24 and a pressure conduit 25, whereby filtered discharge water is recirculated under pressure via the

inlets

11, 12 to the discharge conduit to a location close to the closure arrangement 8 and below this.

According to the invention no discharge water is thus recirculated to the toilet bowl 2 above the closure arrangement 8, but instead the toilet bowl 2 is coupled to a separate upper flushing system 26 for rinsing this and also the closure arrangement 8. This upper flushing system 26 does not use discharge water, but relatively clean water, for example fresh water which is led to an inlet location 28 in the bowl 2 via a water pipe 29. By a high placement of the fresh water tank 27, its own pressure can be used, otherwise a small water pump can be arranged in the conduit 29. An easily-manoeuvred valve 30, for example an electro-magnet valve, maintains the conduit 29 normally closed and is opened for example by means of a push-button with time control for a short limited time of flushing. A second water conduit 31 leads from the water tank 27 to a lower inlet 32 to the lower end of the bowl 2. The lower inlet 32 is directed and formed in order to fill a small amount of water into the space just above the closure arrangement 8 in order to form a small collection of water when the closure arrangement is closed. The lower water inlet 32 also serves to rinse the closure arrangement at the end of flushing in order to rinse the flap. The flap is water-proof and is preferably provided with a seal running around the periphery of the flap. A good seal is best ensured with a flap which, in the closed position, is slanted with respect to the longitudinal axis 17 (see Fig. 2).

The use of the arrangement according to the invention will now be described. The toilet is ready for use when the flap 8 is in its closed position so that a small amount of clean water can be above this. After going to the toilet the discharged products are temporary collected in the stored water and supported by the closed flap 8. Flushing of the toilet is activated for example by means of pressing an electric push-button switch (not shown), whereby the upper flushing system is activated by first injecting flushing water into the upper inlet 28 so that the inside of the toilet bowl 2 is rinsed with a volume of, for instance, about 0,5-1,5 litres. A pump 23 is also started by means of the same activation, substantially simultaneously or in a particular timed-relationship to the rinsing of the bowl, whereby filtered discharge water is led back into the return conduit 18 and injected in a downward direction through the

inlets

11, 12, whereby an underpressure is created below the flap 8 by means of the ejector effect which the recirculated discharge water creates during its injection in a downward direction into the container 14.

The flap 8 is opened quickly at a well-tested time interval after the aforementioned process, whereby the discharged products and the flushing water from the upper flushing system are sucked down into the vessel 14 due to the ejector effect created by the under-pressure and then further downwardly into the discharge conduit 5, and transported with the aid of the recirculated water which is moving quickly downstream from the container 14 into the discharge conduit 5 back to the discharge tank 7.

The flap 8 is then shut with a smooth movement at the same time as clean flushing water from the tank 27 rinses the flap with a small amount of water during automatic injection into the lower inlet end 32, said water also being injected for a short time after closing the flap so that the small amount of water can collect above the flap.

After a predetermined time, the pump 23 is stopped automatically and recirculation of the discharge water ceases.

The toilet is then ready for the next user.

The invention is not limited to the embodiments described above and shown in the drawings, but can varied within the scope of the appended claims. For example the closure arrangement 8 can have a different construction and can be manoeuvred in a different way. The upper flushing system can consist of only an upper flushing section, for example in the form of a flushing ring under the toilet seat 3 with a plurality of nozzle openings. The number of

inlets

11, 12 for the recirculated discharge water and the appearance of the inlets can be varied. Similarly a plurality of toilets can be connected to the same flushing system.

The size of the discharge tank 7 can vary greatly depending on its chosen use. For example the use of the toilet system in an aeroplane or train requires a small tank which is emptied frequently. Even though the system is particularly suitable for transportation means, the system can also be used for holiday cottages where there is no communal sewage system, whereby the discharge tank 7 can be relatively large. In order to provide a more permanent under-pressure in the container 14, this can be connected to a separate container. The flushing sequences may have a different time relationship, e.g. concerning the opening of the flap. The flushing sequences can be controlled completely automatically by a control unit (not shown).

Claims

Arrangement for flushing toilets with flushing systems for water-saving flushing with the aid of recirculating discharge water and comprising at least one toilet with a toilet bowl (2) which, at the bottom, presents a discharge outlet (4) and a closure arrangement (8) for the discharge outlet, whereby an upper flushing system with an inlet for water to the toilet bowl is arranged for flushing of discharged material down to the discharge outlet, whereby a discharge conduit (5) leads from the discharge outlet (4) of the toilet bowl at the closure arrangement to a discharge tank (7), and a lower flushing system with inlet (11, 12) for the recirculating discharge water is arranged to recirculate the discharge water from the discharge tank, characterized in that said inlet (11, 12) for the recirculating discharge water is positioned below the closure arrangement (8) and is directed substantially away from the closure arrangement, so that by the discharge water being injected through said inlet under pressure, an under-pressure is created below the closure arrangement in order that after opening of this, the transport of the discharged material will be furthered in a direction away from the toilet bowl.
Arrangement according to claim 1, characterized in that a container (14) is arranged below the closure arrangement (8), in that said inlet (11, 12) for the recirculated discharge water is arranged in the container and that this comprises a widening of the discharge outlet (4) at its upper end and tapers in a funnel-shape in a downward direction in order to create an increased under-pressure in the container below the closure arrangement.
Arrangement according to claim 1, characterized in that said closure arrangement (8) is arranged to be closed during use of the toilet before flushing and to be closed tightly against the discharge outlet so that discharged material and a small quantity of flushing water are maintained above the closure arrangement during a first phase, in that recirculation of the discharge water is started upon activation of flushing in order to fill the discharge conduit and at least also partially the container during build-up of said under-pressure, and in that in a second phase, the closure arrangement is opened and the discharged material is sucked downwardly into the container and transported to the discharge tank (7).
Arrangement according to claims 1-3, characterized in that the closure arrangement (8) formed by a flap pivotally arranged around an axis (9), the movement of said flap between closed and opened positions being achieved by means of a manoeuvring device (10).
Arrangement according to claim 4, characterized in that the flap (8) is supported at one end and in its closed position is slanted with respect to the longitudinal axis (17) of the discharge outlet (4).
Arrangement according to claim 5, characterized in that the manoeuvring device (10) includes a spring mechanism which biases the flap into the closed position.
Arrangement according to claim 6, characterized in that the flap (8) presents sealing means for water-tight closure against the discharge outlet (4) in the closed position.
Arrangement according to any one of the preceding claims, characterized in that the upper flushing system presents a water inlet (32) to the toilet bowl (2) so that the flap (8) is rinsed during flushing.