SIPHON DEVICE

Abstract: The invention relates to a siphon device or booster with which the speed at which effluent water flows from sanitary facilities to the sewerage may be increased. This siphon device (1) comprises a tank (2) having a liquid feed opening (4) and a liquid drain opening debouching near the bottom thereof, said drain opening being connected to a riser pipe (5) and a drop pipe (7) connected therewith, said drop pipe (7) in turn debouching in a U-shaped pipe portion (8) forming a liquid trap that is open in its position of rest. The tank (2) is relatively shallow and means (21) for boosting the siphoning action are arranged between the tank and the U-shaped pipe portion functioning as a liquid trap. The siphon boost means (21) may comprise an element (22) for guiding the flow of the liquid, configured as a discontinuity in the course of a curved part (6) connecting the riser pipe and the drop pipe. The siphon boost means (21) may also comprise a drop pipe (5) returning parallel to the riser pipe.

Description: Siphon device The invention relates to a siphon device, comprising a tank having a liquid feed opening and a liquid drain opening debouching near the bottom thereof, said drain opening being connected to a riser pipe and a drop pipe connected therewith, said drop pipe debouching in a substantially U-shaped pipe portion forming a liquid trap that is open in its position of rest. Such a siphon device is marketed by the applicant under the name of Gustavsberg 1 s Water Saving System, and is disclosed in EP A 0 Oil 778. The known device comprises a collection tank having a feed opening arranged in the centre of its top wall and a drain opening arranged in the centre of its bottom wall . The feed opening is connected to a collecting conduit, which in turn is connected to the drains of a number of water using sanitary devices, such as toilets, washbasins, showers, bathtubs and the like. The drain opening is connected to a sloping riser pipe, which through a curved part is connected to a vertical drop pipe, which in turn debouches in a U-shaped pipe portion functioning as a water trap. The U-shaped pipe portion has a horizontal drain, which may be connected to a drain conduit having any desired direction. The U- shaped pipe portion is dimensioned such that it does not function as water trap during normal use, but only when a very large amount of water is supplied. The known device, which is also known as booster or flow increaser, is meant for increasing the speed with which effluent water flows from the sanitary facilities to the sewerage, whereby the risks of clogging of the pipes by solid components in the effluent water ad- hering to the walls of the pipes is reduced as much as possible. This is especially important when water saving toilets are used, since the amount of water flowing through the pipe system during each flushing of these toilets will often be insufficient to prevent such clogging from occurring. When using the siphon device the effluent water from the various sanitary facilities is collected in the tank until this is full. The water level in the riser pipe will always be the same as the water level in the tank. The height of the riser pipe is chosen such that when the tank is filled the water is just at the upper brim of the riser pipe, so that when in this situation additional water flows into the tank, the riser pipe overflows into the drop pipe. When the amount of water flowing into the tank is limited, the water flowing from the riser pipe to the drop pipe will eventually flow through the U-shaped pipe portion to the drain, without completely filling the U-shaped pipe portion with water, and thus causing it to function as water trap. When however a larger amount of water flows into the tank which is already filled to the brim, ets will for instance be the case when a toilet is flushed, so much water flows from the riser pipe into the drop pipe that the U-shaped pipe portion is completely filled with water, and thus will function as water trap. When the water from the U-shaped pipe portion flows to the drain, this creates a partial vacuum in the drop pipe, whereby more water is drawn from the riser pipe. This water again fills the U-shaped pipe portion, thus causing this to function as water trap again, and causing a partial vacuum to be created in the drop pipe again when the U-shaped pipe portion is drained. This repeated opening and closing of the water trap takes place ever more quickly, so that eventually a continuous flow of water will be sucked from the riser pipe into the drop pipe and through the water trap. This will continue until the tank is emptied, causing air to be sucked into the riser pipe, and eliminating the partial vacuum in the drop pipe. As the entire contents of the tank are flushed through the drain conduit at once in this way, a relatively high flow speed will result, whereby the risk of solid parts in the effluent water precipitating and adhering to the walls is reduced. The known siphon device has the drawback that for a good siphoning action it is necessary that flushing the toilet results in a sufficiently large increase of the water level in the riser pipe, in order to guarantee that the water trap functions well . To this end the tank is made relatively narrow, so that its surface area is limited and the required relatively large and sudden increase of the water level during a flushing is indeed achieved. In order to have sufficient capacity for maintaining a reasonable speed of flow, the tank must therefore be relatively high. However, this has for its result that the siphon device is not suitable for use in low rise buildings such as houses, since there will normally be insufficient space available for receiving the high tank. The invention therefore for its object to provide an improved siphon device with which this draw- back is obviated. According to this invention this is accomplished in that the tank is relatively shallow and means for boosting the siphoning action are arranged between the tank and the U-shaped pipe portion functioning as liquid trap. By using a relatively shallow tank a device is obtained which may also installed in low rise projects, for instance in the space below the floor. Since in such a shallow tank the rise of the water level during a flushing will as a matter of course be less then in a narrow and high tank, siphon boost means are added, whereby the required action is obtained anyhow. Preferred embodiements of the siphon device of the present invention form the subject matter of the dependent claims . The invention is now explained by way of an example, with reference being made to the annexed drawing in which: figure l is a partly broken away perspective view of a siphon device in accordance with the invention, figure 2 is a longitudinal section along the centre plane of the siphon device shown in figure 1, figure 3 is a sectional view corresponding with figure 2, showing the siphon device in a state with the tank completely filled, and illustrating the various connections, and figure 4 is a sectional view corresponding to figure 2 of the siphon device during use. A siphon device 1 (figure 1) comprises a tank 2 having a feed opening 3 and a drain opening 4 (figure 2) . The drain opening 4 is arranged near the bottom of the tank 2, and is connected to a sloping riser pipe 5. The riser pipe 5 in turn is connected through a curved part 6 to a drop pipe 7. At the bottom of the drop pipe a substantially U-shaped pipe portion 8 is arranged which functions as liquid trap, but which is dimensioned such that it is open in the position of rest. The U-shaped pipe portion 8 functioning as liquid trap in turn is connected to a drain conduit 9. The drain side and the feed side of the siphon device 1 are connected by a vent line 10, which prevents a partial vacuum from being formed at the feed side of the device during siphoning, which could seriously disturb the siphoning action. This vent line 10 has a first part 11 which is connected to the top of the drain p pe 9, enclosing an obtuse angle (of approximately 135 degrees in the shown example) therewith when seen in the direction of flow, and subsequently a conduit part 12 that is substantially perpendicular to the first part 11 and is curved at the location of the curved part 6, and leads to the tank 2. The tank 2 has a central inspection opening 14 in its top wall 13, which may be closed by a panel 15. The vent line 10 comprises an annular line 16, which leads around the inspection opening 14, and finally debouches into an end part 17 leading to the feed opening 3. The vent line 10 also has an inspection opening 27 which is arranged at the transition between the slo- ping first part 11 and the second conduit part 12. This inspection opening 27, which may be covered by a cap 28 (figure 3) is specifically suitable for inspecting the U- shaped pipe portion 8 functioning as water trap, due to the sloping position of the vent line part 11. As described above the tank 2 is relatively shallow and has a sloping side wall 18. The bottom 19 of the tank is also inclined. The feed opening 3 is arranged near the upper edge of the sloping wall 18, and oriented such that a feed pipe 20 to be connected thereto runs substantially parallel to the wall 18. In this way the feed pipe 20, the wall 18 and the bottom 19 constitute something of a "slide", whereby solid components in the effluent water are easily transported unter the influence of gravity, and have no chance of precipitating on the walls. In order to prevent precipitation of solid parts on the walls of the siphon device 1 it is also important that the flow through the device 1 is in prin- ciple in one direction only. The feed pipe 20, the tank 2 , the riser pipe 5 , the drop pipe 7 and the drain pipe 9 in fact constitute a continuous line, without needless interruptions or loops as are present in the known siphon device. As the tank 2 is relatively shallow, and has a relatively large water surface in relation to its capacity, flushing a modern water saving toilet will result in only a slight increase of the water level in the tank 2. Therefore, the siphon device 1 comprises means 21 for boosting the siphoning action. In the illustrated example these siphon boost means 21 are arranged for guiding the flow of liquid through the curved part 6 in such a manner that this flow of liquid "crosses" the drop pipe 7 as quickly as possible. To this end the inner wall 23 of the curved part 6 has a discontinuous course, i.e. the radius of curvature of the curved part 6 exhibits a local stepwise change. The discontinuity 22 is configured as a ridge protruding from the inner wall 23 of the curved part 6. This ridge 22 prevents the liquid from simply flowing along the wail 24 of the drop pipe 7 opposite the riser pipe 5 when the level of liquid in the tank 2 is increased relative to the situation shown in figure 3 in such a way that the liquid flows from the riser pipe 5 to the drop pipe 7. Due to the presence of the flow guiding ridge 22 the flow of liquid separates from the wall 24, and virtually immediately reaches the opposite wall 25 (figure 4) . Air is thereby drawn in under the flow of liquid along the arrow A (figure 5) , whereby a liquid curtain 27 is formed, which closes off the drop pipe 7, and thus functions as a first water trap. In this way a partial vacuum is already created behind the liquid curtain 27 when this liquid curtain 27 flows downwards through the drop pipe 7, whereby liquid is sucked from the riser pipe 5, and the siphoning action is thus started early. Although in the illustrated example the discontinuity is realized by a protruding ridge 22 arranged substantially perpendicular to the direction of flow, other configurations are also conceivable. Thus, the discontinuity could be formed by a ridge 22 protruding from the inner wall 23 of the curved part in the direction of the opposite wall 25 of the drop pipe 7 (figure 5) , whereas the diameter of the pipe in the curved part 6 could also simply be selected to be larger than that of the drop pipe 7, thus also forming a stepwise transition. For optimum starting characteristics of the siphon device it is especially important that the stepwise change in the course of the wall along which the liquid flows takes place as far upstream as possible, so that the flow separates from the wall as soon as possible. Preferably, the discontinuity is therefore arranged already in the curved part 6, that is before the drop pipe 7 when seen in the direction of flow. Instead of a flow guiding element 22, which causes the flow of liquid to separate from the inner wall 23 and to reach the opposite wall 25 of the drop pipe 7, it is also conceivable that the drop pipe 7 is led back parallel to the riser pipe 5, so that the walls 24 and 25 of the drop pipe 7 are inclined. In that case the liquid will fall from the curved part 6 onto the wall 25 under the influence of gravity, whereby also a curtain functioning as a water trap is formed in the drop pipe 7, and the siphoning action is initiated. Furthermore, it is of course also possible to combine such course of the drop pipe with a discontinuity in the curved part 6. In order to increase the siphoning action the curved part 6 may have a larger diameter then the riser pipe 5. To this end the riser pipe 5 is provided with a flaring upper end 26. Hereby a relatively large amount liquid is present in the upper part of the riser pipe 5 when the tank 2 is completely filled. Therefore also relatively much liquid will flow from the riser pipe 5 to the drop pipe 7 at the time that a new amount of liquid is supplied to the full tank 2. The drop pipe 7 may also have a diameter which increases in the direction of flow, and which is changed into a reduced diameter part before the connection with the U-shaped pipe portion 8, for instance by means of a step or a ridge protruding from the wall of the drop pipe 7 (not shown) . In this way the starting characteristics of the water trap 8 are further improved, and thus the siphoning action further boosted. As can be seen in the figures, the entire siphon device 1 is relatively shallow, due to the use of a relatively shallow tank 2, a sloping feed opening 3 arranged at the side of the tank 2, and the relatively short riser pipe 5 and drop pipe 7, and is therefore very suitable for mounting in for instance the crawl space in a low rise home. Furthermore the siphon device 1, which may be formed from several plastic parts by welding, is relatively robust, also due to the specific shape of the vent line 10, which is led around the inspection opening 14 of the tank 2. The required wall thickness of the siphon device 1 may therefore be chosen relatively thin, which has an advantageous effect on the material and manufacturing cost of the device 1. All in all the invention provides a relatively compact and robust siphon device which may be easily manufactured at reduced cost, which has a very small installation height, but has a good siphoning action nevertheless . Although the invention has been illustrated above with reference to a siphon device for use in drai- ning water from sanitary facilities to a sewer, the skilled person will appreciate that this siphon device may be used at all places where there is a need for collecting and subsequently draining liquids at higher rates .

Claims: Claims 1. Siphon device (1), comprising a tank (2) having a liquid feed opening (3) and a liquid drain opening (4) debouching near the bottom thereof, said drain opening (4) being connected to a riser pipe (5) and a drop pipe (7) connected therewith, said drop pipe (7) debouching in a substantially U-shaped pipe portion (8) forming a liquid trap that is open in its position of rest, characterized in that the tank (2) is relatively shallow and means (21) for boosting the siphoning action are arranged between the tank (2) and the U-shaped pipe portion (8) functioning as liquid trap. 2. Siphon device (1) as claimed in claim l, characterized in that the siphon boost means (21) comprise means (22) arranged in a curved part (6) connecting the riser pipe (5) and the drop pipe (7) for guiding the flow of the liquid. 3. Siphon device (1) as claimed in claim 2, characterized in that the flow guiding means (22) are configured as a discontinuity in the course of an inner wall (23) of the curved part (6) . 4. Siphon device (1) as claimed in claim 3, characterized in that the discontinuity constitutes a ridge protruding from an inner wall (23) . 5. Siphon device (1) as claimed in any one of the preceeding claims, characterized in that the siphon boost means (21) comprise a drop pipe (7) returning substantially parallel to the riser pipe (5) . 6. Siphon device (1) as claimed in any one of the preceeding claims, characterized in that the tank (2) has a sloping side wall (18), and the feed opening (3) is arranged near an upper edge of the sloping side wall (18) . 7. Siphon device (1) as claimed in claim 6, characterized in that a feed pipe (20) connected to the feed opening (3) runs substantially parallel to the sloping side wall (18) of the tank (2) . 8. Siphon device (1) as claimed in any one of the claims 2 to 7 , characterized in that the curved part (6) has a larger diameter than the riser pipe (5) . 9. Siphon device (1) as claimed in any one of the preceeding claims, characterized in that the drop pipe (7) has a diameter that increases in the direction of flow. 10. Siphon device (1) as claimed in claim 9, characterized in that the drop pipe (7) comprises a reduced diameter part arranged in front of the connection with the U-shaped pipe portion (8) functioning as liquid trap. 11. Siphon device (l) as claimed in claim 10, characterized in that the reduced diameter part of the drop pipe (7) is formed by a ridge protruding from the wall of the drop pipe (7) . 12. Siphon device (1) as claimed in any one of the preceeding claims, characterized by a vent line (10) connecting the drain side with the supply side of the device (1) . 13. Siphon device (1) as claimed in claim 12, characterized in that the vent line (10) is connected to a drain conduit (9) arranged downstream of the U-shciped pipe portion (8) functioning as liquid trap and encloses an obtuse angle therewith as seen of the direction of flow. 14. Siphon device (1) as claimed in claim 12 or 13, characterized in that the tank (2) has an inspection opening (14) arranged in its top side and the vent line (10) is led around the inspection opening (14) .

Inventors: BENTE ROBERTUS CORNELIS WILHEL, BENTE, ROBERTUS, CORNELIS, WILHELMUS, MARIA
Applicants: BENTE ROBERTUS CORNELIS WILHEL, WISA BV, BENTE, ROBERTUS, CORNELIS, WILHELMUS, MARIA, WISA B.V.
Application year: 1997
Main classification: E03F5
IPC codes: E03D11, E03F5