EP3202995B1 - Water drain system with automatically adjustable discharge flow - Google Patents

Description

The invention relates to a method for regulating the water level on the surface of a green roof and a water drainage system for carrying out the method, in particular such a system which prevents rainwater that falls on a surface from flowing off in an essentially unreduced amount and without a time delay.

The sealing of the soil, especially in cities, means that the sewage system cannot cope with the amount of water that falls when there is heavy rainfall. As a result, streets, sidewalks, etc. are flooded. Conventional building roofs divert the rainwater that has fallen on them almost completely from the roof again without any delay. the US 2015/0218785 A1 for example describes a system for controlling water runoff from a non-green roof. A valve arranged on the roof is opened or closed in a controlled manner by a control device, with weather data transmitted by a weather service being included for control. The purpose is to catch heavy rain and prevent the unhindered entry of water into the sewer system and thus its overload. For this purpose, the valve is closed when a rain detector or the weather data report heavy rain, in order to prevent the rainwater from immediately draining off the roof in the event of heavy rain. The rainwater is left to stand for a while on the roof surface and, after a specified period of time, is completely drained from the roof into the sewer system. In contrast, rainwater is released from green roofs with a time lag. The reason for this is that the plants and the substrate on which the plants are planted store rainwater and only release it after a delay. In addition, the amount of water released is lower, as part of the amount of precipitation evaporates through the surface of the ground and another part is consumed by the plants.

Compared to conventional, non-planted roofs, green roofs have the advantage that the precipitation that has fallen on them is released into the sewer system in a reduced amount and with a time delay. The structure of the plant substrate for the green roof differs depending on the type of plants that are to be planted on the roof. Both single-layer and multilayer structures are known. Usually, the more demanding the plants become, the greater the number of layers. If, for example, perennials, shrubs or trees are to be planted, multilayer structures are usually required, and backwater irrigation is necessary in order to provide the plants with sufficient water. A layer structure for such an intensive green roof thus comprises a water reservoir from which the plants can be continuously supplied with moisture.

The water reservoir enables the uptake and retention of larger amounts of water. However, in order to ensure that the runoff coefficients specified by the authorities, i.e. the permissible runoff amount of water per time, is adhered to even during heavy rainfall, it is necessary to set the runoff from the roof over time. In the DE 19852561 C1 a solution is proposed to the applicant for this. The water drainage system described there has concentric pipes opening into a roof drain, which can be adjusted in relation to one another in such a way that the amount of water running off is limited. The flow rate is predefined, among other things, depending on the size of the area to be drained, the type of roof structure and the amount of precipitation to be expected.

Recently, however, due to climate change and increasingly densely built-up areas, the situation has worsened and the congestion of sewers and waterways has worsened. As a result, floods and floods occur with increasing frequency. Cities and municipalities are increasing the demands on building owners, especially in the case of new buildings, to make a contribution to flood prevention. The limit values for the admissible discharge of wastewater into the sewer system are becoming more and more stringent. The requirements for the retention capacity of green roofs are increasing accordingly. There are many (new) construction areas in which green roofs, mostly with a specified runoff coefficient C according to the Forschungsgesellschaft Landschaftsentwicklung Landschaftsbau e. V. (FLL), through the development plan. In most cases, a discharge coefficient C of 0.5 or 0.3 is used as a dimensioning, which corresponds to a discharge of 50 or 30% compared to a sealed surface with a discharge coefficient of 1 = 100%.

The runoff coefficient C is based on a heavy precipitation event of 300 liters per second and hectare for a duration of 15 minutes. This corresponds to the amount of 27 liters per square meter. 27 liters correspond to the (currently) valid standards and precipitation data the so-called Kostra Atlas (statistical precipitation events, based on data from the German Weather Service (DWD)) in most cities and municipalities, a precipitation event that occurs once a century or at least once every 50 years, depending on the region. However, such "events of the century" are now occurring much more often, and neither the DIN recently adapted to climate change for the measurement of water quantities and the necessary dimensioning of the drainage facilities, nor the revised Kostra Atlas that will be published soon come really close to reality, but rather, due to the system, always lag behind reality after. In addition, the drainage systems, sewer systems, etc. are often still at a level from a few decades ago, i.e. their dimensions are neither adapted to climate change nor to increasing surface sealing.

Increasingly, therefore, on behalf of cities and municipalities, stricter requirements than before are being made and specific discharge quantities are specified, which are significantly lower than the previous specifications according to the discharge coefficient C. For example, values are required that are 1 to 10 liters of peak runoff per second and hectare, and that over the entire duration of the runoff. This often results in values that result in an expiration delay of 5 hours and more, in some cases even 24 hours and more. Occasionally, emptying times of, for example, 3, 6, 12 or 24 hours are specified. It is also important that not only the roof areas are included in the calculations, but the entire property, including other sealed areas such as paths, streets and courtyards. This goes far beyond the previous requirements.

The green roof systems currently on the market have not yet been able to meet the increased requirements. In particular, the greatly extended retention times are usually not achieved. The reason for this is, among other things, that today's systems are usually designed to meet the discharge coefficient C - i.e. only ensure the specified water drainage for the prescribed period of 15 minutes or a little longer. After this period, however, the specified amount of water may then be exceeded again, that is, the amount of water fed into the sewer system increases again. If precipitation continues to fall, the green roof gradually soaks up like a sponge, and when it is completely saturated, the runoff coefficient rises to 1, which means that any further precipitation runs off the roof unhindered and completely. In order to meet the more stringent regulations for better water retention over a longer period of time, an even greater delay is required, i.e. throttling of the runoff quantities, possibly over the entire duration of a heavy rain event or the entire duration of the water runoff, depending on the specifications. Theoretically, it would be conceivable to solve this problem by increasing the storage capacity, but this is usually already obstructed by structural restrictions.

The object of the invention is accordingly to specify a method and a water drainage system which meet these requirements, ensure a high level of water retention even in the case of prolonged heavy rain events and ensure a flexible water balance.

This object is achieved with the method for regulating the water level according to claim 1 and a water drainage system according to claim 11. Preferred embodiments are described in the dependent claims.

The invention relates in one aspect to a water drainage system according to claim 11 for carrying out the method according to the invention, and the method according to the invention according to claim 1 uses a water drainage system for a water contact surface having a drain, which is a roof surface of a green roof, comprising a closure body which is inside or is arranged above the drain and designed to prevent the entry of water into the drain, an actuating device with which the closure body can be moved in order to allow the entry of water into the drain, and a control device for controlling the actuating device, which is formed is to control the actuating device as a function of evaluated weather data.

The water drainage system according to the invention makes it possible, by means of a control device and actuating device, to use the closure body for watertight closure of the drain individually and as required. For this purpose, the closure body can be moved by means of the actuating device from a first position preventing water from entering the drain into a second position in which water can enter the drain. In contrast to the prior art described at the beginning, in which it was possible to specify the opening size of the flow opening and thus the amount of drainage per time according to the respective green roof, the present invention now also enables the amount of drainage not only to be determined according to the respective circumstances adapt, but also change over time. The flow rate is set on the basis of evaluated weather data. This makes it possible, for example, to open the runoff completely in the event of very heavy rainfall, in order to increase the runoff quantity for a limited period of time. In addition, when the rainfall subsides or when it is dry, the drain can be reduced or completely closed in order to prevent the water reservoir on the water contact area from being completely emptied and, for example, insufficient irrigation for a green roof on the water contact area.

In summary, it can be stated that the invention not only allows individual planning and setting of the water storage amount on the water contact surface and the amount drained per time, but also enables an individual, targeted and continuous adjustment of the water balance over the entire operating time. The closure body can be designed in such a way that it can be moved between a position that completely closes the drain and a position that completely releases the drain. In addition, it is possible to design the closure body in such a way that it can assume intermediate positions in which the inflow to the outflow is partially released, so that a smaller outflow quantity can be set than when the outflow is fully released. The controllability of the movement of the closure body and thus the flow rate per time also allows an adjustment practically in real time from an external location and therefore with significantly less effort than before. Although the controllability in real time also enables a very quick reaction to new environmental conditions such as extreme rainfall, a major advantage of the invention is the ability to make predictive settings over the operating time of the water drainage system.

Accordingly, the control device is designed in such a way that it controls the actuation device as a function of evaluated weather data, including externally received and evaluated weather forecast data, including forecast amounts of precipitation. In this case, weather data are expediently used which relate to the respective location at which the water drainage system according to the invention is located. Such weather data are available from various providers, for example in the form of so-called weather apps, which can be called up specifically for a specific predetermined location. This weather data can either be transmitted via cable or, what is preferred, wirelessly to the water drainage system. It is particularly preferred to transmit the weather data by mobile radio. The receiving device provided for receiving the weather data in the water drainage system is then a mobile radio device, in particular a smartphone, in this case. However, it could also be a tablet PC or any other suitable receiving device. This is arranged at a suitable location in the water drainage system and connected to the control device so that the weather data received by the receiving device can be transmitted to the control device. The data is preferably transmitted here by means of a cable, but wireless transmission options are also conceivable, for example a Bluetooth connection.

The control is preferably carried out not only on the basis of the weather data for the current day, but also taking into account the weather forecast data for at least the following day, preferably for several days in advance. In this way it is possible to make preparations for expected heavy rain events or longer dry periods. For example, it is possible to calculate the storage requirements for the precipitation to be expected for the following days. In order to be able to absorb this expected volume of precipitation, storage space on the water contact surface can be cleared, if necessary, in order to create space for the new precipitation. The control of the water drainage system takes place in such a way that the actuating device opens the closure body for a calculated period of time and releases the drain so that as much water runs off the water contact surface as corresponds to the volume of the new precipitation to be expected. If desired, a safety margin can also be planned in order to ensure sufficient storage volume even if the precipitation is actually greater than announced. If weather forecast data for several days in advance are taken into account, the stored water can be drained from the water contact area in good time so that the permitted flow rate is not exceeded during the draining of the water to clear storage volumes before the expected heavy rain event occurs. After the required amount of water has been drained from the water contact surface (the calculated opening period for the drain has expired), the control device transmits a control signal to the actuating device, whereupon the actuating device reduces or completely closes the drain by moving the closure body, so that the forecast heavy rain, as soon as it begins to fall, it is collected and is not diverted from the water contact surface into the sewerage system, or only with the permitted delay.

Conversely, if a dry period is expected, the flow of water from the water contact surface can be interrupted. The drain is closed so that no more water runs off and any rain that is still falling before the announced dry period is collected. In a further development of the invention, an irrigation system can be provided which can also be controlled by the control device. This is put into operation by the control device when the water stored on the drainage surface is no longer sufficient to irrigate a green roof. In a preferred embodiment of the invention, a water level indicator can be provided to determine the stored amount of water, which either continuously transmits measured values to the control device or forwards a warning if the water level falls below a predetermined value. Then or alternatively after a predetermined time has elapsed, within which the water level has not recovered to a sufficient value, the control device activates the irrigation device in order to ensure an adequate supply of water to the plants. The water level indicator can also be used regardless of its presence an irrigation device can advantageously be used to determine the water level on the water contact surface, so for example also in the case described above to determine the available free storage volume in preparation for rainfall.

The information and data required for calculating the control processes are preferably stored in the control device, which has a suitable memory for this purpose. Necessary data are, in particular, the data already used from the state of the art for the design of green roofs or gravel roofs with water retention, such as in particular data for calculating the maximum storage volume, the permissible runoff quantities, the retention capacity, etc. Drainage donation required by the authorities (e.g. permitted runoff quantities in liters / second. hectares or similar), the water contact area (the area that can be used as a retention area), the so-called catchment areas (surrounding areas from which water hits the water contact area can reach), the precipitation to be expected for the respective location (usually the precipitation parameters specified by the authorities in accordance with the DIN standard or Kostra Atlas for the measurement frequency of extreme weather events), the emptying time (period within which the calculated amounts of precipitation water flow away from the retention areas d ürfen), the accumulation height (results in the absorbable water volume with the size of the retention area), the number of drains in the water drainage area and the drainage cross-section. If there is more than one drain on the water contact surface, each of these drains is expediently provided with an automatically actuated closure body according to the invention in order to control the flow rate of each of these drains as a function of the evaluated weather data. In a manner known per se, the parameters mentioned can be used to calculate not only the maximum drainage cross-section but also the maximum opening cross-section of the drainage opening for each individual drainage of the water drainage system according to the invention. Furthermore, values for the calculated evaporation and, for example, structural values can be included in the calculation and stored in the memory. Based on these values, the maximum accumulation volume and the maximum flow rate per time from the water contact area can be calculated. Furthermore, volume losses, for example due to evaporation, preferably depending on the outside temperature, can be taken into account. The basic design and basic settings of the water drainage system and their calculations correspond in principle to those of the state of the art.

In order to be able to calculate the storage requirement for the forecast precipitation in advance, the corresponding inflow volumes for the respective catchment areas and water contact areas known for the location are determined by a weather app or other weather forecast forecast precipitation amounts calculated. For the predicted precipitation values, which are specified in liters per square meter, for example, inflow volumes calculated in advance for the respective amounts of precipitation in a certain period of time are stored for the respective location in the memory of the control unit. These inflow volumes then in turn result in the storage volumes that have to be made available to accommodate the predicted amounts of precipitation. On the basis of these storage volumes, the amounts of water per time that have to be drained from the water contact surface in order to create space for the expected precipitation are then calculated. Accordingly, it is then calculated for how long - and, if necessary, how far, if only a partial opening of the drain is possible - the at least one drain must be opened so that the calculated drain volume can be drained before the predicted precipitation event occurs. According to these calculated control parameters, the control device actuates the actuating device, which in turn opens the drain completely or partially for the calculated period of time by moving the closure body in accordance with the calculated parameters in order to drain the calculated drain volume. Following this, the runoff is then completely or partially closed again (for example depending on the specified runoff coefficient) in order to be able to absorb the calculated precipitation volume.

In the method described above, the calculations are calculated on the basis of values and calculation formulas previously stored in the control device, taking into account the externally transmitted weather data. In an alternative variant that is not claimed, however, it is also possible to carry out these calculations on the basis of the weather data at an external location, outside the water drainage system. For example, the computer center of an operator can be used for the calculation, which calculates the required control parameters for the respective location and then transmits the control parameters to the control device of the water drainage system according to the invention in a wired or wireless manner. In this way, too, it is possible to control the actuating device on the basis of evaluated weather data. The wireless transmission can, as already described above, take place by means of mobile radio, for which purpose a mobile radio device is installed in the water drainage system.

In a further preferred embodiment, the water drainage system comprises not only a receiver, but also a transmitter for transmitting messages and / or data to an external receiver. This transmitter is preferably again a mobile radio device, expediently the same mobile radio device that is already used as the receiver of the weather data. The transmitter, specifically the mobile radio device, can on the one hand serve to send measured values from the system to a to transfer to an external data center, where these measured values are used to carry out calculations in order to determine control data, which are then sent back to the mobile radio device of the water drainage system again via mobile radio. As an alternative or in addition to this function, the transmitter can also be used to send status messages and, in particular, error messages to an external receiver. In the event of a malfunction, maintenance or repair of the water drainage system can be carried out very quickly. This maintenance or repair is particularly preferably carried out by remote maintenance, that is to say by external access to the control device and via this to the connected components, which considerably reduces the effort and the costs.

The water drainage system according to the invention and the method according to the invention are designed for use on green roofs, hereinafter referred to as green roofs for short, on which a certain volume of water is to be retained for a certain period of time and / or fed to the sewer system with a time delay and in a controlled manner. The water contact area is a roof area that has a drain through which water is discharged into the sewer system. In terms of its basic structure, the water drainage system according to the invention corresponds to such water drainage systems as have already been used in the prior art, in particular those such as those shown in FIG DE 198 52 561 C1 are described. The water drainage system usually comprises a shaft, which surrounds a cavity with its side walls. This shaft is set up above the drain on the roof surface. The closure body, the actuating device with which it is moved, and preferably also the control device are expediently located within this shaft. In a variant, the shaft can have through openings in its side walls directly above the water contact surface, which allow unhindered entry of water located on the water contact surface into the cavity of the shaft. If a certain water reservoir is to be permanently retained on the water contact surface, the through openings can also be located at a certain distance from the water contact surface in the side walls of the shaft, so that water can only enter the cavity when a certain water level is reached. In order to prevent water from penetrating below the shaft walls from the roof surface into the cavity and flowing unchecked through the drain in the roof surface, the lower edge of the shaft should in this case be placed on the roof surface as watertight as possible self-adhesive butyl seals, compression tapes (elastic closed-cell foamed plastic tapes) and multi-component curable liquid plastic sealants or combinations thereof. In order to enlarge the mounting surface for the seal on the shaft, the lower edge of the shaft can be issued in the form of a flange. The seal is then expediently attached to the side of the flange facing in the direction of the roof surface. Alternatively, the formation of a water reservoir on the water contact surface can also be achieved in that a pipe is located around or inserted into the drain, which protrudes over the water contact surface at a height that corresponds to the desired accumulation height of the water on the roof surface (cf. for example too DE 198 52 561 C1 ). The height depends, among other things, on the type of green roof or gravel fill chosen and is usually between 2 and 8 cm for green roofs. The maximum water absorption volume of the roof surface is calculated from the contact area of the water on the roof surface and the accumulation height - if necessary minus the volume of other structures.

In order to prevent water standing on the water contact surface from entering the drain unimpeded, if necessary after exceeding the maximum intended accumulation height, a closure body is provided according to the invention which prevents the entry of water into the drain when it is in its closed position within or above the Drain is arranged. In the case of an arrangement inside the drain, it completely closes the inlet cross-section to the drain, either by being plugged into the drain itself and closing it, or by closing a pipe or other supply line that opens into the drain. In the following, when "inside (or" above) the drain "is mentioned, for the sake of simplicity the variant" inside (above) a pipe opening into or surrounding the drain or some other supply line "should also be included. The same applies to expressions that relate to the inlet opening into the drain, the drain cross section or the like. Here, too, without this being expressly mentioned, the inlet opening of the pipe opening into the drain (or a corresponding supply line), its drain cross-section, etc., is also addressed as an alternative. As already described, the alternative with a pipe or supply line usually relates to systems in which a permanent water reservoir is kept on the water contact surface. Within the scope of the invention it is possible to combine the basic structure of these systems with the locking body automatically actuated according to the invention. Is preferred However, it is also necessary to provide the permanent water reservoir in such systems by corresponding actuation of the closure body. There are therefore no drainage barriers such as pipes that can prevent the complete drainage of water from the roof, rather a drain is used, the inlet opening of which is essentially in one plane with the water contact surface. The prevention of the complete drainage of water from the water contact surface as well as the amazement up to the desired accumulation height of the permanent water reservoir are achieved exclusively by appropriate actuation of the closure body, the water level being determined in a manner known per se by means of a water level meter. The procedure described has the advantage that the storage volume of the permanent water reservoir is also available, if necessary, to accommodate expected heavy rainfalls. In this case, the control device can cause the actuating device to remove the closure body from the drain, so that the permanent water reservoir is completely or partially emptied so that there is sufficient capacity for the expected rainfall.

In the case of a closure body arranged within the drain, it is sufficient if this is at least partially located within the drain. In the context of the invention, “arranged within the drain” also includes a partial arrangement within the drain. In the simplest form, it can be a plug, for example, which closes the inlet opening into the drain. The actuating device is designed accordingly to push the stopper into the inlet opening to close the drain and to lift it off from the inlet opening to open it. The stopper can also be partially lifted from the inlet opening, so that an annular gap with a smaller opening cross-section than the inlet opening as a whole results.

A closure body arranged above the drain should be understood to mean a closure body which covers the inlet cross section of the drain and / or completely surrounds it without being inserted into the drain. In the simplest case, it could be, for example, a cover that lies over the inlet cross-section of the drain. However, it could also be a hollow body arranged above the drain, the side walls of which are closed at least up to a certain height and thus prevent the entry of water into the drain. In this case, the inner surface of the hollow body enclosed by the side walls is located above the drain, that is, a cross section of the closure body covers the inlet cross section into the drain. The definition “above the outlet” therefore does not necessarily mean that the closure body is in any case completely above the inlet cross-section down the drain. The latter is especially the case when the inlet cross-section of the drain is in the water contact area. In this case, the closure body expediently lies or stands on the water contact surface and prevents water from entering the drain from the sides. However, if a pipe or the like is present in or around the drain in order to be able to generate a water reservoir, a closure body arranged above the drain can also be pulled down laterally around the pipe, for example down to the water contact surface. It is crucial, however, that the closure body extends upwards via the inlet opening of the pipe, which is also the inlet opening into the drain, and thus prevents the direct entry of water into the pipe and from there into the drain if the maximum possible accumulation height of the Water (according to the height of the pipe) is reached. In a variant, the closure body can be designed like a pot, the bottom of the pot running above the inlet opening into the drain. However, it is also possible to design the closure body as a hollow body open at the top, for example as a hollow cylinder. In the closed position, the height of the walls of the hollow body protrudes above the inlet opening of the drain. Since the closure body is open at the top in this case, the closure body only acts as a closure for the drain until the water level on the water contact surface has reached the height of the walls of the hollow body. However, this is quite intentional, as certain roof structures can only cope with a maximum water level. (NB: The maximum water level is not the accumulation height of the permanent water storage tank, but a higher water level which, if exceeded, allows water to pass over the sealing on the building side and thus damage the building itself. A maximum water level could also be predetermined by the statics of the building.) By suitable selection of the wall height of the hollow body closure body, an emergency drain can be provided which can be used to quickly drain the water from the roof structure if the maximum manageable water level is exceeded.

From what has been said above, it follows that the closure body used according to the invention does not necessarily have to prevent the entry of water into the drain for all water levels on the water contact surface. In the context of the invention, it is rather sufficient if the closure body prevents water from reaching the drain unhindered for certain water levels. After a certain water level has been exceeded, it may even be desirable for the closure body to enable an emergency drain that prevents further accumulation of water on the water contact surface.

If the closure body is arranged around a water accumulation pipe or the like, it can be pushed directly onto the water accumulation pipe, as is basically already the case in FIG DE 19852561 C1 is described. However, it is preferred if the closure body is arranged at a lateral distance from the water accumulation pipe. In a particularly preferred variant, whether with or without a water accumulation pipe, the closure body is designed as a hollow body and in particular as a hollow cylinder which, in its closed position, rests with its lower edge on the water contact surface. In order to ensure a secure stand, the lower wall area is preferably folded over to the side in order to produce an enlarged contact surface. This support surface expediently runs essentially parallel to the water contact surface. To improve the tightness, the contact surface facing the water contact surface can be covered with an elastically deformable material. This can be, for example, a coating made of an elastomeric plastic or the sealing materials already described in connection with the contact surfaces of the shaft, such as sealing tapes, for example. The side wall of the hollow body is self-contained and free of openings, at least in its area facing the water contact surface. In one variant, the height of the side wall corresponds to the desired maximum water level on the water contact surface. In another variant, the side wall extends beyond the maximum water level, but above the latter has at least one inlet opening through which water can enter the interior of the hollow body when the maximum water level is exceeded.

For a closure body arranged above the drain, the actuating device is preferably designed in such a way that it can lift the closure body upwards from the inlet opening of the drain or move it to the side. The former is particularly preferred. The outflow speed can be influenced by how far the closure body is removed from the inlet opening and how large the gap is selected between the closure body and the inlet opening. The amount of outflow is controlled accordingly via the time for which the closure body releases the outflow.

The actuation device with which the closure body is moved can in principle be designed in any suitable manner known from the prior art. Suitable components of the actuating device include, for example, a cable mechanism, a pivot lever, a push or pull rod and / or a toothed or threaded rod. Suitable combinations of several of these elements are of course also possible. The type of drive is also not restricted further. In principle, any suitable movement device can be used, for example an electric motor, an electromagnetic, hydraulic or pneumatic drive. The use of a pneumatic drive is preferred because of the low maintenance requirement in the humid and strong temperature fluctuations environment, which also has the advantage of an almost wear-free and loss-free power transmission.

In a further development of the water drainage system according to the invention, an outer wall arranged on the water contact surface is arranged laterally around the closure body. This outer wall, which basically allows water to enter its interior and for this purpose has at least one passage opening, can serve, for example, to prevent or at least reduce the entry of contaminants. For this purpose, the at least one passage opening is expediently provided with a particle filter, for example in the form of a sieve, a filter mat or some other filter material. As an alternative or in addition, the outer wall serves to fasten parts of the actuating device for the closure body and / or guide elements which guide and facilitate the movement sequences of the closure body.

In a preferred embodiment, the closure body is connected to at least one pivot lever which is pivotably mounted on a support strut, which in turn is attached to the outer wall which is arranged around the closure body. The pivoting of the pivoting lever and thus the raising and lowering of the closure body takes place by moving a push rod which acts on an arm of the pivoting lever.

As already mentioned, the actuating device - like the control device, the receiving device and an optionally present transmitting device, in particular in the form of a mobile radio device - is expediently arranged in the interior of a well located on the water contact surface. The upper end of the shaft remote from the roof surface forms a maintenance opening which enables access to the components of the water drainage system present in the cavity and thus their easy maintenance. This maintenance opening is expediently closed with a removable or hinged cover. This cover is preferably lockable, so that the components arranged in the shaft are protected not only from the effects of the weather, but also from access by unauthorized persons. A solar module, with which the power-consuming components of the water drainage system can be supplied with power, can be provided on the cover or, alternatively, raised in the vicinity of the shaft. In order to store the electricity generated by the solar module, an electricity storage device, for example in the form of a rechargeable battery, is also expediently provided. All components are particularly useful For example, actuating device, control device, receiving device and transmitter, supplied with solar power. In this way, a completely self-sufficient operation of the water drainage system is possible.

Fig. 1

einen Querschnitt durch ein Kiesdach mit einem erfindungsgemäßen Wasserabflusssystem. Die beschriebene Variante gehört lediglich insofern zur Erfindung, als sie sich auf einzelne Komponenten des Wasserabflusssystems und deren Betrieb bezieht, nicht jedoch hinsichtlich der Verwendung auf einem Kiesdach;

Fig. 2

einen Querschnitt durch ein Gründach mit einem erfindungsgemäßen Wasserabflusssystem;

Fig. 3

eine weitere Querschnittsdarstellung eines erfindungsgemäßen Wasserabflusssystems;

Fig. 4

eine Schnittansicht entlang der Linie X-X der Figur 3;

Fig. 5

eine Teil-Schnittansicht eines alternativen Ausführungsbeispiels im Bereich oberhalb eines Abflusses;

Fig. 6

eine Draufsicht auf ein Verschlusselement ähnlich demjenigen in Figur 3;

Fig. 7

eine Teil-Schnittansicht entlang der Linie Y-Y der Figur 5 und

Fig. 8

eine Draufsicht auf die Außenwandung 6 in Richtung des Pfeils Z der Figur 5.

The invention is to be explained in more detail below with reference to drawings. The drawings are purely schematic and serve only to illustrate preferred embodiments of the invention, without this being restricted thereto. In the figures, the same reference symbols denote the same parts. Show in detail:

Fig. 1

a cross section through a gravel roof with a water drainage system according to the invention. The variant described belongs to the invention only insofar as it relates to individual components of the water drainage system and their operation, but not with regard to use on a gravel roof;

Fig. 2

a cross section through a green roof with a water drainage system according to the invention;

Fig. 3

a further cross-sectional view of a water drainage system according to the invention;

Fig. 4

a sectional view along the line XX of FIG Figure 3 ;

Fig. 5

a partial sectional view of an alternative embodiment in the area above a drain;

Fig. 6

a plan view of a closure element similar to that in FIG Figure 3 ;

Fig. 7

a partial sectional view along the line YY of FIG Figure 5 and

Fig. 8

a plan view of the outer wall 6 in the direction of the arrow Z in FIG.

Figures 1 and 2 show water drainage systems 1, installed on a gravel roof and a green roof. In the case of the in Figure 1 gravel roof K shown is applied to the roof surface U, which is at the same time the water contact surface, a bed of gravel k. Above an outlet A, through which water flowing off the roof is fed to the sewer system and which has an essentially circular inlet opening A1 lying in the plane of the water contact surface U, a shaft 7 is set up, which encloses a cavity 71 and has a removable cover 70 is locked. The side walls of the shaft 7 have through openings, which are not visible in the cross-sectional view, through which water can get into the interior 71 of the shaft 7. The shaft surrounded by the gravel corresponds in height to the height of the gravel fill k. The cover 70 is not covered with gravel and is therefore easily removable, so that the cavity 71 of the shaft 7 is accessible. The water drainage system 1 according to the invention is arranged in the interior of the shaft 7. This will be explained in more detail later.

Before that, however, the structure of a green roof G should be described, as shown schematically in Figure 2 is shown. Shown again is a cross section of a roof D in the area of a roof drain A. To protect the roof surface, some protective coverings SB are first applied to the roof surface U. In the area of the drain A, a shaft 7 with a water drainage system 1 according to the invention is set up. In the example shown, the shaft 7 is connected to the roof surface in a watertight manner. The green roof surrounding the shaft is one with a permanent water reservoir WS. This is a cavity that can be filled with water and extends essentially over the entire roof surface. This cavity is defined by pallet-like plastic hollow components, which are laid out over a large area on the roof surface in a manner known per se. Above these cavity components, a drainage layer DS is applied, which is covered by a filter layer FS, which is intended to prevent the penetration of plant substrate PS into the drainage layer and water reservoir. Perennials and shrubs are planted in the substrate. The water that is used to supply them is sucked up through the drainage layer from the water reservoir by means of capillary forces and taken up by the roots of the plants. The wall structure of the shaft 7 is such that the lower side wall 72 does not have any through openings up to a height which essentially corresponds to the height of the water reservoir WS, so that water is dammed up to this height. At a height that essentially corresponds to the height of the drainage layer DS, the side wall 72 has a passage opening through which water can enter the interior 71 of the shaft. The upper part of the side wall, adjoining the plant substrate PS, is then again free of through openings. This structure ensures that water can accumulate at the level of the water storage tank WS, but an additional, undesired increase in the amount of water in the green roof can enter the interior of the shaft 7 via the drainage layer DS and can be drained from there through the drain A. . The closed upper part of the side wall 72 prevents plant substrate from penetrating into the shaft 7.

For a sufficient supply of the green roof vegetation, it is necessary, on the one hand, that the water storage tank WS is always sufficiently filled with water, but on the other hand, there is no waterlogging. The water balance is regulated with the aid of the water drainage system 1 according to the invention. This also allows the water balance to be regulated in advance, So, for example, to drain water in advance from the water reservoir and from the roof surface U, if heavy precipitation is to be expected, which would exceed the storage capacity of an already at least partially filled water reservoir. This is to be done in the following on the basis of the Figures 1 to 3 are explained in more detail.

In the examples shown, the water drainage system 1 according to the invention is in each case arranged in a shaft 7 which is set up above a drain A on the water contact surface U. Some of the components of the water drainage system are arranged on an intermediate floor 73 which is attached inside the shaft above the maximum water level. On the intermediate floor 73 there is an actuating device 3 which moves the closure body 2 upwards or downwards. For example, it can include a motor 38 that drives a pinion, which in turn moves a rack 33 up and down. Alternatively, the closing body 2 could also be raised and lowered, for example, by means of a push rod or threaded rod, a cable 31 or the like. The actuation device 3 is controlled by means of a control device 4. The control device 4 can either be operated using an operating element, not shown here, such as a keyboard or a touchscreen, in order to manually send commands to the actuation device 3 and / or request information, etc. required programs, data, etc. are stored in a memory 40 of the control unit.

A particular advantage of the water drainage system according to the invention is that it can also be operated from a remote location. This is made possible by a mobile phone / smartphone 5, which functions both as a receiving device and as a transmitter of the water drainage system and is connected to the control device 4 by means of a data cable 50. By selecting the cell phone 5, it is possible to get in contact with the control device 4 and to transmit commands to it or to read out data and / or messages. In this way it is possible, for example, for error messages output by the control device 4 to be transmitted via the mobile phone 5 to a mobile phone or another recipient of a user so that the user or a service provider can react to the error message. The repair can then in turn be carried out by remote maintenance via the mobile phone 5 to the control device 4, so that only in the rarest of cases does a service technician have to carry out a repair or maintenance work on site. The described configuration of the water drainage system 1 also makes it possible, in particular, to control the actuating device 3 via the control device 4 and thus to move the closure body 2 by manual intervention and thus to regulate the water balance on the roof from a different location.

However, it is particularly advantageous if a weather app is installed on the mobile phone, with which weather data specific to the location can be transmitted to the mobile phone 5. These weather data received by means of the mobile phone 5 are then transmitted via the data cable 50 to the control device 4 and evaluated there. For the evaluation, the precipitation values stored in the memory 40 are compared with the precipitation values transmitted by the weather app. Corresponding total volumes are assigned to the stored precipitation values, which have to be absorbed in the roof's water reservoir for the expected amount of precipitation per time corresponding to the catchment area of the roof. For example, a predicted amount of precipitation of x liters per square meter over the prediction period is assigned a volume of water of y liters to be absorbed in this period. These stored values are determined in advance and stored specifically for the roof structure in a manner known per se. Other values stored in the memory can include the retention area specific for the roof structure, the maximum accumulation volume, specific evaporation values, the maximum drainage volume per time, the specified retention values, such as the permissible discharge rate, the specified discharge coefficient, the specified retention time, etc. Contain values or other data required for the water balance.

Furthermore, it is possible to attach a water level indicator 10 in the area of the water reservoir, which also transmits values to the memory 40 of the control device 4. The parameters required for an optimal water balance in the green roof can be calculated from these stored values by comparing them with the expected precipitation values provided by the weather app. Specifically, by comparing these values, parameters are determined with which, through targeted lifting or lowering of the closure body 2, enough water is accumulated in the water reservoir or drained from it that, on the one hand, there is always a sufficient amount to supply the vegetation and, on the other hand, if heavy rainfall is expected , so much storage space is freed up in the water storage tank that the then falling rain can be absorbed in the water storage tank without exceeding the maximum permissible or desired water level.

If, for example, the mobile phone 5 transmits data from the weather app that predicts dry days for the following week, the control device 4, after comparing the data with the stored values and scenarios, causes the actuating device 3 to lower the closure body 2 and to close the inlet opening A1 of the drain A. to catch the rain forecast for the current week in the water storage tank WS. The stored precipitation is then available available to the plants during the dry season. Temperature values that are supplied by a temperature sensor 11 connected to the control device 4 can be used to take into account the water loss due to evaporation as well as a possibly increased water requirement of the plants at high temperatures when calculating the necessary amounts of water.

If the water level indicator 10 reports a water level that has fallen below a predetermined value in the course of the dry period and the forecast data do not indicate an imminent end of the dry period, the control device 4 causes an irrigation device BW installed on the roof to supply water to the roof. This can either be done for a predetermined period of time or until the water storage tank has been refilled to the predetermined minimum value.

If, on the other hand, the weather app predicts heavy rainfall for the coming days and the evaluation in the control device 4 shows that the water reservoir is already filled to the point that these amounts of rainfall can no longer be absorbed, the actuating device is prompted to remove the closure body in good time before the start of the rainfall 2 to be raised so long and so far that an amount of water runs off the roof that at least corresponds to the expected precipitation.

To supply the power-consuming components with power, a solar module SM is arranged on the cover 70, to which a power storage device in the form of a rechargeable battery AK is assigned. The connection between the battery and consumers is not shown here for the sake of clarity.

The embodiment of the Figure 1 shows a closure body 2 in the form of a plug which narrows towards the drain A, which in its closed position, shown in FIG Figure 1 is shown, is inserted with its lower end into the drain and thus closes the inlet opening A1. Depending on how far the closure body 2 is raised upwards, it can fully or partially open the inlet opening A1 (with the release of an annular gap).

Figure 2 shows an alternative embodiment of a closure body 2, the diameter of which is larger than the diameter of the inlet opening A1, so that the closure body 2 covers the inlet opening A1 in its closed position and closes it in this way. Instead of being lifted, the inlet opening could alternatively also be completely or partially released in that the closure body 2 is shifted to the side. For this purpose, the closure body could for example be arranged in lateral guide rails and with a push rod or another suitable movement device are connected, which is controlled in an analogous manner as described above by the control device.

The closure body in Figure 3 differs from the closure bodies of the Figures 1 and 2 in that it is not a solid body, but a hollow body. Specifically, a hollow cylinder is used here as the closure body, which is arranged above the inlet opening A1 of the drain A in such a way that its side wall completely encloses the inlet opening. This is schematically shown in Figure 4 which is a cross-sectional view taken along line XX of FIG Figure 3 is. The area 22 covered by the closure body 2 and shown here with transverse stripes is so large that it more than covers the opening cross section A1 of the drain A. In this respect, this type of closure body is also referred to as being arranged above the drain. In its closed position, as in Figure 3 shown, lowered to the water contact surface, the hollow cylindrical closure body 2 prevents the entry of water into the drain A as long as the water level does not exceed the height of the side wall of the hollow cylinder. Appropriately, the height of the side wall of the hollow cylinder 2 is selected so that it corresponds to the maximum desired or permissible water level on the water contact surface. If the water level continues to rise above this height, water flows over the edge of the hollow cylinder 2 and from there through the drain A. In this way, an emergency overflow can be implemented that works even if the closure body can no longer be lifted due to a defect by means of the actuating device 3, which is here connected to a cross strut of the closure body 2.

Figure 5 shows an alternative arrangement of the in connection with Figure 3 discussed hollow cylinder closure body 2. The closure body 2 is used in a roof structure with permanent water storage WS, which is an alternative to that of Figure 2 represents. There are no raised openings in the side wall of the shaft 7 here. Instead, the height of the permanent water reservoir WS is set in a manner known per se by means of a pipe A2 which is inserted into the drain A with a corresponding protrusion. The inlet opening A1 into the drain A is thus above the water contact surface U. Water can only enter the drain A when the water level exceeds the protruding height of the pipe A2. In this case too, however, the drainage of water can be prevented by closing the drain A with the closure body 2. For this purpose, this is slipped over the pipe A2 so that water can only get into the drain when the water level is higher than the height of the side wall of the closure body. As mentioned, however, it is general it is preferred not to provide the water reservoir WS via mechanical barriers, but solely by damming up by means of the closure body.

Figures 6 to 8 describe a particularly preferred embodiment of a hollow body closure body 2. The arrangement above the drain A basically corresponds to that in connection with Figures 3 to 5 was discussed. The closure body 2 itself again essentially has a hollow cylindrical shape, but in this case the lower edge is folded over towards the interior of the hollow cylinder and forms a contact surface 21 which is essentially parallel to the water contact surface. In order to achieve a better seal with respect to the water contact surface, the contact surface 21 is provided over the whole area with a layer 25 of an elastomeric plastic. The closure body 2 is arranged within an annular outer wall 6 which, in its lower wall area towards the water contact surface, has slot-shaped passage openings 60 through which water can pass into the interior. The openings 60 can be covered with a filter material in order to prevent dirt particles from entering the interior. At the same time, the outer wall 6 serves to fasten parts of the actuating device for moving the closure body 2.

To fasten the parts of the actuating device, three cross struts 61 are used, which run from a central fastening ring 62 to the upper edge of the outer wall 6 and are connected to it. A push rod 32 is guided through the central opening of the fastening ring 62 and is coupled to the drive device (for example a motor) of the actuating device 3 and can be moved up and down in the direction of the double arrow. An annular plate 37 is attached to a lower end of the push rod, for example between two screw nuts 36 which are screwed onto a thread at the lower end of the push rod. A pivot lever 30 is pivotably mounted on the ring plate 37. For this purpose, a fastening tab is used, for example, which protrudes upwards over the ring plate 37. It is shown here only with dashed lines because it does not lie within the cutting plane. A bolt 35 attached to the fastening strap is passed through a hole at the inner end of the pivot lever, so that the pivot lever 30 can be rotated about this bolt. The swing lever 30 has a curved shape. Approximately in the middle, in the most protruding area of the curvature, the pivot lever 30 has a further hole through which a further bolt 35, which is attached to a fork-shaped holder 63, is guided. The fork bracket 63 is attached to one of the support struts 61. The outer end of the pivot lever 30 is also perforated, a further bolt 35 is inserted into the perforation, and via this a second pivot lever 34 is pivotably connected to the pivot lever 30. Through a perforation at its opposite end is the second pivot lever 34 movably attached to a fastening tab 24, which in turn is firmly connected to the side wall 20 of the closure body 2. Swivel lever mechanisms are attached to the other two support struts 61 in the same way.

The lifting and lowering of the hollow cylinder closure body 2 takes place by moving the push rod 32 up and down, which - controlled by the control device 4 - is driven by the motor of the actuating device. If the push rod 32 is pressed down, for example, it is followed by the inner end of the pivot lever 30, which is mounted on the ring plate 37. The pivot lever 30 therefore pivots about the central pin 35, which is mounted on the fork bracket 63, and its outer end moves upwards. As a result, the closure body 2, which is connected to the pivot lever 30 via the pivot lever 34, is raised upwards. When the push rod 32 is pulled up, the pivoting process takes place in the opposite direction, and the closure body 2 is lowered.

Claims (11)

1. A method for regulating the water level on a water contact surface (U) having at least one drain (A) and configured as a roof surface having a water drain system, comprising:

   - a closing body (2) arranged inside or above the at least one drain (A) and configured to prevent water from entering the at least one drain (A),

   - an actuator (3) by which the closing body (2) can be moved to allow water to enter the at least one drain (A),

   - a control apparatus (4) for controlling the actuator (3), which is configured to control the actuator (3) in dependence on evaluated weather data, comprising externally received and evaluated weather forecast data, comprising forecast precipitation amounts, and

   - a receiving device (5) for receiving the weather forecast data, which is connected to the control apparatus (4) for the purpose of transmitting the received weather forecast data, comprising the steps of:

   - receiving weather data by means of the receiving device (5),

   - transmitting the weather data from the receiving device (5) to the control apparatus (4),

   - comparing the weather forecast data with reference values stored in a memory of the control apparatus (4),

   - selecting control parameters according to the determined reference values and transmitting the control parameters to the actuator (3),

   - if necessary, actuating the actuator (3) and moving the closing body (2) to adjust the water level on the water contact surface (U),

   characterized in that

   the water contact area (U) is the roof surface of a green roof, and

   the inflow volumes are calculated for the precipitation amounts forecast by a weather app or other weather forecast taking into account the weather forecast data,

   the storage volumes that must be provided to absorb the forecast precipitation amounts are calculated based on these inflow volumes,

   the storage volumes are used to calculate the amounts of water per time that must be drained from the water contact surface (U) to provide space for the expected precipitation,

   it is calculated for how long and, optionally, how far the at least one drain (A) needs to be opened in order to drain the calculated discharge volume before the forecast precipitation event occurs, and

   the control apparatus (4) actuates the actuator (3), which in turn, according to the calculated parameters, opens the drain (A) completely or partially for the calculated period of time by moving the closing body (2) in order to drain the calculated discharge volume.
2. The method according to claim 1, wherein the receiving device (5) is a mobile communications device and in particular a smartphone.
3. The method according to claim 1 or 2, wherein a transmitter connected to the control apparatus (4) is provided for transmitting messages and/or data to an external receiver, and wherein in particular the mobile communications device serves as the transmitter.
4. The method according to any one of claims 1 to 3, wherein the closing body (2) is configured to close the inlet opening (A1) into the drain (A), and the actuator (3) is configured to lift the closing body (2) off the inlet opening (A1) in upward direction or to displace it laterally.
5. The method according to any one of claims 1 to 3, wherein the closing body (2) has a wall (20) which completely surrounds the inlet opening (A1) into the drain (A), and is configured in particular as a hollow body, preferably as a hollow cylinder, and wherein the actuator (3) is configured to lift the closing body (2) off the inlet opening (A1) in upward direction or to displace it laterally.
6. The method according to claim 5, wherein the wall (20) has at least one of the following characteristics:

   - it has no openings at least in its region facing the water contact surface (U),

   - it is folded over laterally in its region facing the water contact surface (U), wherein the folded-over region forms a contact surface (21) running essentially parallel to the water contact surface (U), the contact surface (21) preferably being covered with an elastically deformable material.
7. The method according to any one of claims 4 to 6, wherein the closing body (2) is surrounded by an outer wall (6) which has at least one passage opening (60) at least in its region facing the water contact surface (U), the closing body (2) being mounted so as to be movable in a height direction of the outer wall (6).
8. The method according to any one of claims 1 to 6, wherein the actuator (3) comprises a pivoted lever (30), a cable pull mechanism (31), a push or pull linkage (32), and/or a toothed or threaded rod (33).
9. The method according to claim 7 or 8, wherein the closing body (2) is connected to at least one pivoted lever (30) pivotally mounted on a support strut (61) fixed to the outer wall (6), and wherein a push rod (32) is provided for actuating the pivoted lever (30).
10. The method according to any one of claims 1 to 9, comprising at least one solar module (9) for supplying power to at least one of the following apparatuses:

    - the actuation apparatus (3),

    - the control apparatus (4),

    - the receiving device (5)

    - the transmitter.
11. A water drain system (1) for a water contact surface (U) having a drain (A) and configured as a roof surface of a green roof, comprising:

    - a closing body (2) arranged inside or above the drain (A) and configured to prevent water from entering the drain (A),

    - an actuator (3) by which the closing body (2) can be moved to allow water to enter the drain (A),

    - a control apparatus (4) for controlling the actuator (3), which is configured to control the actuator (3) in dependence on externally received and evaluated weather forecast data, comprising forecast precipitation amounts, and

    - a receiving device (5) for receiving the weather forecast data, which is connected to the control apparatus (4) for the purpose of transmitting the received weather forecast data, configured for carrying out the method according to any one of claims 1 to 10.

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