METHOD AND SYSTEM FOR DISCHARGING A WASTE STREAM FROM A TOILET AND SIPHON INSTALLATION FOR USE THEREWITH

Description

[0001] The invention relates to a method for discharging a waste flow which consists of liquid and solid parts and comes from the flushing of a toilet, wherein the waste flow is accelerated at least once, and wherein prior to acceleration at least a part of the liquid is separated from the waste flow, and only this separated liquid is accelerated and fed back again to the waste flow. Such a method is known, for instance from WO 00/08267 A by the present applicant.

[0002] Particularly in situations where a toilet is flushed with a relatively small amount of water, as is the case in a modern, water-saving toilet having a cistern of small volume, the speed of the waste flow is often not sufficient to transport the solid parts over the full length of the discharge pipe into the sewer system. The consequence hereof is that these solid parts are left somewhere in a relatively flat part of a discharge pipe, and there form an obstacle blocking the solid parts of subsequent flushes. This eventually brings about an accumulation which will result in blockage of the discharge pipe.

[0003] In order to prevent this it is therefore known to locally accelerate the waste flow consisting of liquid and solid parts. Use is often made for this purpose of a flow increaser or 'booster' through which the waste flow is guided. In this flow increaser the waste flow is temporarily stored in a tank or reservoir until, after several flushes, the level in the tank has risen so far that it overflows. A siphoning action then results whereby the waste flow is as it were 'sucked' out of the tank of the flow increaser. The waste flow hereby acquires a considerably greater speed than it had when leaving the cistern, so that the solid parts will be entrained over a greater distance, and the risk of blockage of the discharge pipes is thus reduced.

[0004] A drawback of the known method is that the flow increaser must be given a relatively voluminous form in order to ensure a sufficient capacity, and thus a sufficiently great acceleration of the waste flow, and to also prevent blockage by solid parts which do after all remain for some time in the flow increaser. A flow increaser is for instance marketed at the moment by applicant under the name "Gustavsberg's Water Saving System", which is intended to be incorporated in a shared discharge pipe of a number of households. This known flow increaser is provided with a relatively narrow but high tank which is so large that it is only suitable for application in high-rise projects.

[0005] In addition, a method of applicant is also known for discharging a waste flow which is described in WO 98/03743 A, and wherein use is made of a flow increaser with a relatively flat structure which is intended for installation in the crawl space of low-rise residential buildings. While this flow increaser is lower than the above described model, it is also wider so that a relatively large amount of space must also be left clear therefor. Furthermore, as a result of the low structure and the associated large surface area, special hydrodynamic measures are necessary in this flow increaser in order to ensure that an adequate siphoning action is still obtained when there is a small rise in the liquid level.

[0006] In addition to their large dimensions, both the known types of flow increaser have the drawback that their operation can be very adversely affected, particularly by fat residues which are for instance present in waste water from bathrooms or kitchens. Such fat residues are deposited in the flow increaser when the waste flow is standing still therein and adhere strongly to all surfaces so that they are not readily flushed away. Such fat residues ultimately result in (partial) clogging of the flow increaser, whereby the flow speed in the whole discharge system can become insufficient to ensure a reliable transport, particularly of the solid parts, to the sewage system.

[0007] The above-identified prior art document WO 00/08267 A discloses a method for discharging a waste flow consisting of liquid and solid parts having the features of the preamble of claim 1. This method is performed in an accelerator or flow increaser that is arranged around a vertical discharge pipe. At least a part of the liquid flowing along the walls of the pipe is separated from the waste flow and flows into the accelerator, which comprises a siphon installation. This siphon installation debouches in the vertical discharge pipe. Liquid is collected in the siphon installation until it overflows, which will cause the entire contents of the siphon installation to be emptied into the discharge pipe, thus flushing away all solid parts in the pipe. This document does not indicate where the accelerator is located in relation to the toilet.

[0008] The prior art document US 4 242 765 A discloses a waste disposal system and a method for its use. The system includes a toilet and an underfloor holding tank that is in communication with the toilet bowl. The toilet is flushed with just enough fluid to transport waste to the holding tank. The holding tank accumulates waste, flush fluid and waste fluid from uther sources until sufficient wastes accumulate to actuate a valve between the holding tank and a sewer.

[0009] A further method is known from WO 98/03743.

[0010] The invention now has for its object to provide a method of the above described type, wherein the stated drawbacks do not occur. According to the invention this is achieved in a method according to claim 1.

[0011] In this way it is possible to suffice with a very small amount of water to flush the toilet, because the transport function is already supported by the acceleration immediately upon leaving the toilet. The flow increaser can also be embodied very compactly since it only has to deal with the waste flow from the toilet. In addition, the risk of clogging of the flow increaser is considerably reduced because fat residues are no longer carried therethrough.

[0012] By guiding only that part of the waste flow which actually contributes toward the acceleration, i.e. the liquid, through the flow increaser, this flow increaser can be given a considerably more compact form. In addition, the response behaviour of the flow increaser is in this way improved because it will no longer be influenced by the presence of solid parts in the flow increaser, while the acceleration caused by the flow increaser moreover becomes reproducible.

[0013] The separation can be performed most effectively during a vertical movement of the waste flow, while the horizontal feedback ensures that the total height of the path where the separation takes place remains limited.

[0014] The waste flow is preferably accelerated by means of a siphoning operation, wherein the waste flow is collected and only accelerated after reaching a determined volume. Use can hereby be made for the acceleration of a simple system without moving parts which is operated by the waste flow itself. Furthermore, the effect of the acceleration is thus enhanced by accumulating the waste flow. This is particularly the case when the volume required for the acceleration is reached only after at least three successive flushes of the toilet. Using for instance a flush volume of only 2.5 litres, as used in a so-called Ultra-Low Flush Toilet (ULFT), a volume of 6 litres (the present standard) can thus still be achieved for the transport through the discharge pipes.
The invention further relates to a system for discharging a waste flow which consists of liquid and solid parts and which comes from the flushing of a toilet adapted to perform the above described method. The prior art discharge system disclosed in WO 00/08267 comprises the features of the preamble of claim 4. The discharge system according to the present invention is characterized by the characterising portion of claim 4. In view of the limited space available in the vicinity of a toilet, the siphon installation can thus be built in under the toilet.

[0015] The volume at which the siphon installation becomes active can, as stated, advantageously amount to more than twice the flush volume of the toilet.

[0016] According to a preferred embodiment of the invention, the discharge system is provided with means placed between the discharge pipe and the siphon installation for separating out of the waste flow and feeding to the siphon installation at least a part of the liquid, and means connected to the siphon installation for feeding the accelerated liquid back again to the waste flow.

[0017] The siphon installation is preferably provided with a feed opening connected to a standing part of the discharge pipe, and the separating means comprise an inflow edge at least partially bounding the feed opening and connecting smoothly onto a wall of the standing part of the discharge pipe. In this manner the liquid can be separated very easily, making use of the fact that the liquid will flow for the most part along the walls of the standing part of the discharge pipe, while the solid parts will usually drop downward through the middle of the pipe.

[0018] In order to further minimize the space occupied, the siphon installation can be arranged to the side of the standing part of the discharge pipe.

[0019] For fitting purposes it is recommended here that the standing part of the discharge pipe and/or the siphon installation is formed integrally with the toilet. The toilet can thus be placed with a part of the discharge pipe and the siphon installation by a single fitter in one operation without further operations being necessary elsewhere in the discharge system. This saves time and cost and moreover reduces the chance of errors.

[0020] The invention will now be elucidated on the basis of an embodiment, wherein reference is made to the accompanying drawing, in which:

Fig. 1 shows a section through a toilet with a part of a discharge system according to the invention connecting thereto,

Fig. 2 shows a section through a siphon installation applied in the discharge system of fig. 1, and

Fig. 3 and 4 are views corresponding with fig. 2 of the siphon installation during different stages of uses.

[0021] A toilet 1 comprises a toilet bowl 2, a cistern 4 connected thereto via a flush pipe 3 and a liquid trap 6 connecting to an outlet 5 of bowl 2. In the shown embodiment cistern 4 has a very small volume of for instance 2.5 litres, whereby toilet 1 can be characterized as an Ultra-Low Flush Toilet (ULFT). Liquid trap 6 has an outflow opening 7 to which connects a system 8 for discharging a waste flow F coming from toilet 1. This waste flow F consists of liquid L and solid parts S. This discharge system 8 comprises a discharge pipe 9 with a standing part 10 and a lying part 11 (fig. 1).

[0022] The flush volume of toilet 1 is so small that only bowl 2 can be cleaned herewith and the thereby created waste flow F can be transported through liquid trap 6. This volume is however wholly insufficient for the further transport of waste flow F through discharge pipe 9 to a sewer connection. Discharge system 8 is therefore provided with means 12 for accelerating waste flow F. These accelerating means 12 are arranged according to the invention directly at the outflow opening 7 of liquid trap 6.

[0023] In the shown embodiment accelerating means 12 comprise a siphon installation arranged round and adjacently of standing part 10 of discharge pipe 9. The siphon installation and the standing conduit part 10 can herein be formed integrally with toilet 1 or be mounted on toilet 1 prior to delivery, so that the fitting operations remain limited to placing of toilet 1 and connection thereof to the lying part 11 of discharge pipe 9.

[0024] In order to prevent the operation of the siphon installation being affected by the solid parts S in waste flow F, means 13 are arranged on the inflow side of the siphon installation for separating at least a part of the liquid L from waste flow F. These separating means 13 here comprise an inflow edge 15 fitting smoothly onto a wall 14 of the standing conduit part 10 and inclining radially outward, and a deflecting edge 16 which is located opposite inflow edge 15 and which inclines radially inward as seen in the dropping direction (fig. 2). These two edges 15, 16 bound an annular feed opening 17 of the siphon installation.

[0025] The siphon installation itself comprises a tank 18 which is connected to feed opening 17 and provided with a siphon conduit 19 which debouches on the underside of tank 18. The volume of tank 18 is such that a number of flushes can be stored therein in order to enable a considerable quantity of flushing liquid to be introduced into the discharge pipe at one time. Tank 18 is for instance dimensioned such that 6 litres of flushing liquid are delivered, since many pipe systems are dimensioned for this quantity.

[0026] Siphon conduit 19 is formed by a riser pipe 20 which is connected over a bend part 21 to a drop pipe 22. Arranged on the underside of drop pipe 22 is a pipe part 23 which is curved in a U-shape and which functions as a liquid seal, but which is dimensioned such that it is open in the rest position. This U-shaped pipe part 23 functioning as liquid seal debouches, as stated, on the underside of tank 18 into discharge pipe 9, this in the lying part 11 thereof. Because the feed side and the discharge side of the siphon installation communicate with each other via discharge pipe 9, no vent line is required therebetween as in conventional flow increasers.

[0027] The operation of discharge system 8 is now as follows. When toilet 1 is flushed, the waste flow F coming therefrom will reach discharge pipe 9 via outlet 5, liquid trap 6 and outflow opening 7. Here the waste flow F flows through the standing conduit part 10 to the lying conduit part 11. In standing part 10 the liquid L here flows mainly along the pipe wall 14, while the solid parts S drop through the middle of pipe 9. At the position of the siphon installation the liquid L then follows the inflow edge 15 which connects smoothly onto pipe wall 14, and thus flows into tank 18 where in the first instance it is collected (fig. 3). The solid parts S drop together with a small part of the liquid L further through the middle of pipe 9. Because there is thus only little liquid available for further transport of the solid parts S, these will accumulate at the beginning of the lying conduit part 11. With each flushing the liquid level increases further in tank 18 and in riser pipe 20 until it eventually reaches bend part 21.

[0028] When in this situation extra liquid flows into tank 18, riser pipe 20 will overflow via bend part 21 into drop pipe 22. As long as the amount of liquid flowing into tank 18 is small, the liquid flowing out of riser pipe 20 to drop pipe 22 will eventually flow via the U-shaped pipe part 23 to the outlet without this pipe part 23 herein being completely filled with liquid and thus functioning as liquid seal.

[0029] However, as soon as a larger amount of liquid flows into the tank 18 already filled to its edge, as will be the case when toilet 1 is flushed, so much liquid flows out of riser pipe 20 into drop pipe 22 that the U-shaped pipe part 23 is completely filled with liquid, and thus functions as liquid seal. When the liquid L from this pipe part 23 flows to the discharge pipe, an underpressure is hereby created in drop pipe 22, whereby liquid is once again drawn out of riser pipe 20. This liquid once again fills pipe part 23, whereby it functions once again as liquid seal, and an underpressure is again generated in drop pipe 22 when pipe part 23 empties. This repeated opening and closing of the liquid seal takes place more and more quickly, whereby an uninterrupted flow of liquid will eventually be drawn out of riser pipe 20 into drop pipe 22 and through liquid seal 23 (fig. 4). This continues until tank 18 is empty, whereby air will be drawn into riser pipe 22 and the underpressure in drop pipe 22 will be removed.

[0030] Since in this manner the whole content of tank 18 flushes through discharge pipe 9 at one time, a relatively high flow speed will be created therein, whereby the solid parts S which have settled in the lying conduit part 11 are flushed away.

[0031] The waste flow, by being accelerated immediately upon leaving the toilet or at least the liquid present therein being accelerated, can thus be transported in reliable manner through the discharge pipe to a sewer connection despite the relatively small volume of flushing water flowing through the toilet per flush. The flow increaser used herein can further be given a relatively small form, while the risk of blockage by fat residues is wholly obviated. Furthermore, due to the structural integration of the accelerating means with the toilet, the installation thereof can be considerably simplified.

[0032] Although the invention is elucidated above on the basis of an embodiment, it will be apparent to the skilled person that it is not limited thereto. Many variations in the configuration of the siphon installation and the separating means can be envisaged. The scope of the invention is therefore defined solely by the appended claims.

Claims

1. Method for discharging a waste flow (F) which consists of liquid (L) and solid parts (S) and comes from the flushing of a toilet (1), wherein the waste flow (F) is accelerated at least once, and wherein prior to acceleration at least a part of the liquid (L) is separated from the waste flow (F), and only this separated liquid (L) is accelerated and fed back again to the waste flow (F), the acceleration of the liquid (L) takes place when it flows out of the toilet (1), or immediately thereafter, characterized in that the waste flow (F) being discharged, when it flows out of the toilet (1) or (F) being discharged, when it flows out of the toilet (1) our immediately thereafter, first in a substantially vertical path and, after a bend, in a substantially horizontal path, the separation and acceleration taking place in the substantially vertical part of the path and the accelerated liquid (L) being fed back in the substantially horizontal part of the path.

2. Method as claimed in claim 1, characterized in that the waste flow (F) is accelerated by means of a siphoning operation, wherein the waste flow (F) is collected and only accelerated after reaching a determined volume.

3. Method as claimed in claim 2, characterized in that the volume required for the acceleration is reached only after at least three successive flushes of the toilet (1).

4. System (8) for discharging a waste flow (F) which consists of liquid (L) and solid parts (S) and which comes from the flushing of a toilet (1), comprising at least one discharge pipe (9) for the waste flow (F) connecting to an outflow opening (7) of the toilet (1) and means (12) connected to the discharge pipe (9) for accelerating the waste flow (F), the accelerating means (12) comprising a siphon installation which is adapted to collect the waste flow (F) and which only becomes active for accelerating thereof once a determined volume has been reached, the accelerating means (12) are positionable at the position of or close to the outflow opening (7) of the toilet (1), characterized in that the discharge pipe (9) has a lying part (11), the siphon installation has a relatively flat form and is adapted to feed back the accelerated liquid (L) to the lying part (11) of the discharge pipe (9).

5. Discharge system (8) as claimed in claim 4, characterized in that the volume at which the siphon installation becomes active amounts to more than twice the flush volume of the toilet (1).

6. Discharge system (8) as claimed in claim 4 or 5, characterized by means (13) placed between the discharge pipe (9) and the siphon installation for separating out of the waste flow (F) and feeding to the siphon installation at least a part of the liquid (L), and means connected to the siphon installation for feeding the accelerated liquid (L) back again to the waste flow (F).

7. Discharge system (8) as claimed in claim 6, characterized in that the siphon installation is provided with a feed opening (17) connected to a standing part (10) of the discharge pipe (9), and the separating means (13) comprise an inflow edge (15) at least partially bounding the feed opening (17) and connecting smoothly onto a wall (14) of the standing part (10) of the discharge pipe (9).

8. Discharge system (8) as claimed in claim 7, characterized in that the siphon installation is arranged to the side of the standing part (10) of the discharge pipe (9).

9. Discharge system (8) as claimed in claim 7 or 8, characterized in that the standing part (10) of the discharge pipe (9) and/or the siphon installation is formed integrally with the toilet (1).

Ansprüche

1. Verfahren zum Ableiten eines Abwasserstromes (F), der aus Flüssigkeit (L) und festen Teilen (S) besteht und vom Spülen einer Toilette (1) stammt, wobei der Abwasserstrom (F) mindestens einmal beschleunigt wird, und wobei vor dem Beschleunigen mindestens ein Teil der Flüssigkeit (L) von dem Abwasserstrom (F) getrennt wird und nur die getrennte Flüssigkeit (L) beschleunigt und wieder in den Abwasserstrom (F) zurückgespeist wird, wobei die Beschleunigung der Flüssigkeit (L) stattfindet, wenn sie aus der Toilette (1) herausströmt (1), oder unmittelbar danach, dadurch gekennzeichnet, dass der Abwasserstrom (F), wenn er aus der Toilette (1) herausströmt oder unmittelbar danach, zunächst in einer im Wesentlichen vertikalen Bahn und nach einer Biegung in einer im Wesentlichen horizontalen Bahn abgeleitet wird, wobei die Trennung und die Beschleunigung in dem im Wesentlichen vertikalen Teil der Bahn stattfinden und die beschleunigte Flüssigkeit (L) in dem im Wesentlichen horizontalen Teil der Bahn zurückgespeist wird.

2. Verfahren gemäß Anspruch 1, dadurch gekennzeichnet, dass der Abwasserstrom (F) mittels eines Absaugvorgangs beschleunigt wird, wobei der Abwasserstrom (F) gesammelt und erst nach dem Erreichen eines bestimmten Volumens beschleunigt wird.

3. Verfahren gemäß Anspruch 2, dadurch gekennzeichnet, dass das für die Beschleunigung erforderliche Volumen erst nach mindestens drei aufeinanderfolgenden Spülungen der Toilette (1) erreicht wird.

4. System (8) zum Ableiten eines Abwasserstromes (F), der aus Flüssigkeit (L) und festen Teilen (S) besteht und von dem Spülen einer Toilette (1) stammt, aufweisend mindestens ein Ableitungsrohr (9) für den Abwasserstrom (F), das mit einer Abflussöffnung (7) der Toilette (1) verbunden ist, und mit dem Ableitungsrohr (9) verbundene Mittel (12) zum Beschleunigen des Abwasserstromes (F), wobei die Beschleunigungsmittel (12) eine Siphoneinrichtung aufweisen, die angepasst ist, um den Abwasserstrom (F) zu sammeln, und die nur dann zum Beschleunigen davon aktiv wird, wenn ein vorbestimmtes Volumen erreicht wird, wobei die Beschleunigungsmittel (12) an der Position von oder nahe bei der Abflussöffnung (7) der Toilette (1) positionierbar sind, dadurch gekennzeichnet, dass das Ableitungsrohr (9) einen liegenden Teil (11) aufweist, die Siphoneinrichtung eine verhältnismäßig flache Form hat und angepasst ist, um die beschleunigte Flüssigkeit (L) in den liegenden Teil (11) des Ableitungsrohres (9) zurückzuführen.

5. Ableitungssystem (8) gemäß Anspruch 4, dadurch gekennzeichnet, dass das Volumen, bei dem die Siphoneinrichtung aktiv wird, mehr als das Zweifache des Spülvolumens der Toilette (1) beträgt.

6. Ableitungssystem (8) gemäß Anspruch 4 oder 5, gekennzeichnet durch zwischen dem Ableitungsrohr (9) und der Siphoneinrichtung angeordnete Mittel (13) zum Trennen des Abwasserstroms (F) und Einspeisen von zumindest einem Teil der Flüssigkeit (L) in die Siphoneinrichtung, und durch mit der Siphoneinrichtung verbundene Mittel zum erneuten Einspeisen der beschleunigten Flüssigkeit (L) in den Abwasserstrom (F).

7. Ableitungssystem (8) gemäß Anspruch 6, dadurch gekennzeichnet, dass die Siphoneinrichtung mit einer Zuführöffnung (17) versehen ist, die mit einem aufrechten Teil (10) des Ableitungsrohres (9) verbunden ist, und die Trennmittel (13) einen Einströmrand (15) aufweisen, der zumindest teilweise die Zuführöffnung (17) begrenzt und nahtlos an eine Wand (14) des aufrechten Teils (10) des Ableitungsrohres (9) angeschlossen ist.

8. Ableitungssystem (8) gemäß Anspruch 7, dadurch gekennzeichnet, dass die Siphoneinrichtung an der Seite des aufrechten Teils (10) des Ableitungsrohres (9) angeordnet ist.

9. Ableitungssystem (8) gemäß Anspruch 7 oder 8, dadurch gekennzeichnet, dass der aufrechte Teil (10) des Ableitungsrohres (9) und / oder die Siphoneinrichtung einstückig mit der Toilette (1) ausgebildet ist.

Revendications

1. Procédé pour évacuer un flux de déchets (F) qui se compose de parties liquides (L) et solides (S) et provient de la chasse d'eau de toilettes (1), dans lequel le flux de déchets (F) est accéléré au moins une fois, et dans lequel avant l'accélération, au moins une partie du liquide (L) est séparée du flux de déchets (F), et seul ce liquide (L) séparé est accéléré et ramené à nouveau au flux de déchets (F), l'accélération du liquide (L) a lieu lorsqu'il s'écoule hors des toilettes (1), ou immédiatement après, caractérisé en ce que le flux de déchets (F) est évacué, lorsqu'il s'écoule des toilettes (1) ou immédiatement après, d'abord sur une trajectoire sensiblement verticale et ensuite après un coude, sur une trajectoire sensiblement horizontale, la séparation et l'accélération ayant lieu dans la partie sensiblement verticale de la trajectoire et le liquide (L) accéléré est ramené dans la partie sensiblement horizontale de la trajectoire.

2. Procédé selon la revendication 1, caractérisé en ce que le flux de déchets (F) est accéléré au moyen d'une opération de siphonage, dans lequel le flux de déchets (F) est collecté et seulement accéléré après avoir atteint un volume déterminé.

3. Procédé selon la revendication 2, caractérisé en ce que le volume requis pour l'accélération est atteint seulement après au moins trois chasses successives des toilettes (1).

4. Système (8) pour évacuer un flux de déchets (F) qui se compose de parties liquides (L) et solides (S) et qui provient de la chasse d'eau de toilettes (1), comprenant au moins un tuyau d'évacuation (9) pour le flux de déchets (F) se raccordant à une ouverture de sortie (7) des toilettes (1) et des moyens (12) raccordés au tuyau d'évacuation (9) pour accélérer le flux de déchets (F), les moyens d'accélération (12) comprenant une installation de siphon qui est adaptée pour collecter le flux de déchets (F) et qui devient active pour son accélération seulement une fois qu'un volume déterminé a été atteint,
les moyens d'accélération (12) sont positionnables dans la position de ou à proximité de l'ouverture de sortie (7) des toilettes (1), caractérisé en ce que le tuyau d'évacuation (9) a une partie horizontale (11), l'installation de siphon a une forme relativement plate et est adaptée pour ramener le liquide accéléré (L) à la partie horizontale (11) du tuyau d'évacuation (9).

5. Système d'évacuation (8) selon la revendication 4, caractérisé en ce que le volume auquel l'installation de siphon devient active, représente plus de deux fois le volume de la chasse d'eau des toilettes (1).

6. Système d'évacuation (8) selon la revendication 4 ou 5, caractérisé par des moyens (13) placés entre le tuyau d'évacuation (9) et l'installation de siphon pour séparer le flux de déchets (F) et alimenter l'installation de siphon au moins avec une partie du liquide (L), et des moyens raccordés à l'installation de siphon pour ramener le liquide (L) accéléré au flux de déchets (F).

7. Système d'évacuation (8) selon la revendication 6, caractérisé en ce que l'installation de siphon est prévue avec une ouverture d'alimentation (17) raccordée à une partie verticale (10) du tuyau d'évacuation (9), et les moyens de séparation (13) comprennent un bord d'entrée (15) délimitant au moins partiellement l'ouverture d'alimentation (17) et se raccordant régulièrement sur une paroi (14) de la partie verticale (10) du tuyau d'évacuation (9).

8. Système d'évacuation (8) selon la revendication 7, caractérisé en ce que l'installation de siphon est agencée sur le côté de la partie verticale (10) du tuyau d'évacuation (9).

9. Système d'évacuation (8) selon la revendication 7 ou 8, caractérisé en ce que la partie verticale (10) du tuyau d'évacuation (9) et/ou l'installation de piston est formée de manière solidaire avec les toilettes (1).

Drawing