Backflow preventer for a wastewater pipe and method for operating a backflow preventer

Abstract

The present invention relates to a backflow preventer (1) for installation in a wastewater pipe, in particular for use in a wastewater pipe of a building, comprising a housing (2) with a flowable channel (7) which can be closed in an open- and fluid-tight manner via at least one shut-off element (8); a first tubular connection spigot (10) which is provided for connection to a wastewater pipe arranged upstream of the backflow preventer (1); and a second connection spigot (11) which is provided for connection to a wastewater pipe arranged downstream of the backflow preventer (1), wherein the two connection spigots (10, 11) are arranged on the housing (2) such that they form a continuous pipe with the flowable channel (7); wherein the shut-off element (8) is displaceable perpendicular to the axial extent of the flowable channel (7) and can be actuated via a linear actuator (9).Furthermore, the present invention relates to a system for monitoring a wastewater pipe of a building comprising the backflow preventer according to the invention and a method for operating the backflow preventer according to the invention.

Description

The present invention relates to a backflow preventer for installation in a wastewater pipe, in particular for use in a building's wastewater pipe, and to a system for monitoring a building's wastewater pipe. Furthermore, the present invention relates to a method for operating the backflow preventer according to the invention. State of the art Backflow preventers of the aforementioned type are used in the state of the art in wastewater pipes of a building to prevent wastewater from being forced back into the building when the water level in the sewer is high. Currently, backflow preventers are known to automatically close using gravity via their integrated backflow flaps. However, prolonged operation can lead to the accumulation of dirt, particularly in the area of ​​the sealing gaskets, which can compromise a watertight seal. Consequently, in the worst-case scenario, wastewater can enter a building's utility or even living spaces unnoticed during heavy rain or flooding, causing significant damage. A backflow preventer of the aforementioned type is known, for example, from DE 20 2007 017 945 U1. Based on the aforementioned prior art, the object of the present invention is to provide an improved backflow preventer, in particular a backflow preventer for installation in a wastewater pipe of a building, which ensures improved operational reliability. Description of the invention According to the invention, the problem is solved by a backflow preventer with the features of claim 1. The backflow preventer according to the invention for installation in a building's wastewater pipe, in particular for use in a building's wastewater pipe, comprises a housing with a flow-through channel that can be closed in an open- and fluid-tight manner via at least one shut-off element; a first tubular connection spigot, which is provided for connection to a wastewater pipe arranged upstream of the backflow preventer, and a second connection spigot, which is provided for connection to a wastewater pipe arranged downstream of the backflow preventer, wherein the two connection spigots are arranged on the housing such that they form a continuous pipe with the flow-through channel. The backflow preventer according to the invention is characterized in that the shut-off element is displaceable perpendicular to the axial extent of the flow-through channel and can be actuated via a linear actuator. A backflow preventer with the previously described arrangement of a housing, two connection spigots, and a shut-off element is proposed. Unlike conventional designs, this preventer does not close by gravity but is actively actuated by a linear actuator. To close the backflow preventer when necessary, the shut-off element is moved perpendicular to the axial extent of the flow channel. The combination of a shut-off element that is movable or travelable perpendicular to the axial extent of the flow channel and a linear actuator that actively actuates it ensures a reliable seal in the event of backflow. This is particularly advantageous when contaminants have accumulated in the sealing area due to extended operating times.To improve the closing effect, the lower edge of the shut-off element can preferably be designed with a tapered cross-section, so that the shut-off element cuts through or displaces any existing dirt. A further advantage of the proposed backflow preventer is its high flexibility with regard to installation position. Since the shut-off element is actively driven by the linear actuator, the backflow preventer according to the invention can be installed horizontally, vertically, or at an angle without impairing its complete sealing capability. This allows for easy integration into existing wastewater pipes, for example, exposed ones. This also makes the solution suitable for the subsequent renovation of older buildings at risk of backflow. The terms “horizontal”, “vertical” or “slanted” refer to the orientation of the flow channel in relation to the ground level of a building. If the present application specifies a positional orientation that describes an arrangement perpendicular to the axial extent of the channel through which the flow passes, then deflections of up to 10° are also included in principle. The backflow preventer is advantageously designed to be highly resistant and to withstand typical pressures, for example a pressure of up to 1.4 bar or more. Further advantageous embodiments of the invention are specified in the dependent claims. The features listed individually in the dependent claims can be combined in a technologically meaningful way and can define further embodiments of the invention. Furthermore, the features specified in the claims are specified and explained in more detail in the description, which also presents further preferred embodiments of the invention. The shut-off element is preferably located in the housing between the two connection ports. The shut-off element is thus situated directly within the flow path or flow channel of the backflow preventer. The connection ports can be designed as separate components that are connected to the housing, for example via screw connections. Alternatively, the connection ports can also be designed as integral parts of the housing. According to an advantageous embodiment, the shut-off element is arranged, at least in the area of ​​the flow channel through the housing, between two sealing elements, which are preferably designed in the form of elastic profile seals. The shut-off element is thus guided and sealed between the two sealing elements during the closing and opening process. Elastic profile seals adapt to any unevenness in the material and thus ensure a reliable seal, thereby guaranteeing a long-lasting and low-maintenance function of the backflow preventer. The sealing elements are advantageously arranged in recesses within the flow channel. They can preferably extend along the entire inner circumference or a portion thereof. For example, the sealing element on the upstream side (upstream of the shut-off element) can extend over the entire circumference, while the sealing element on the downstream side (downstream of the shut-off element) has a cutout in a lower circumferential section facing a lower edge region of the shut-off element. The reverse is also possible. Advantageously, in this area, the recess in the inner wall of the flow channel can also be wider downstream than the rest of the recess to provide a space for any contaminants that may accumulate in the lower recess section over time. In a particularly advantageous design, the shut-off element is completely enclosed within the housing. The shut-off element is thus fully surrounded by the housing in both the closed and open positions. When open, it is located outside the direct flow of wastewater, protecting it from mechanical damage and contamination, which in turn has a beneficial effect on the operational reliability of the backflow preventer. To ensure the functionality of the backflow preventer in the event of a failure of the automatic actuator, the shut-off element preferably has a handle located outside the housing, allowing the shut-off element to be manually opened and / or closed in a fluid-tight manner. The proposed backflow preventer can thus be operated reliably even if the linear actuator fails, thereby increasing operational reliability and flexibility. According to a preferred embodiment of the invention, the linear actuator is arranged inside the building and completely enclosed by it. In one possible embodiment, both the shut-off element and the linear actuator are thus completely enclosed within the housing, effectively protecting them from damage caused by external influences. In an alternative embodiment, the linear actuator can also be arranged outside the housing. It is then attached to the outside of the housing using a mounting unit. The force transmission to the shut-off element can be effected, for example, via a coupling element. The coupling element can be connected directly to the shut-off element or via a piston rod of the shut-off element that protrudes from the housing and provides a mechanical connection to the piston rod of the linear actuator.An arrangement outside the housing facilitates access to the linear actuator, for example in case of maintenance or when replacing the linear actuator. The linear actuator can be designed as an electric, pneumatic, or hydraulic actuator, with the use of an electric linear actuator being preferred because, unlike hydraulically or pneumatically operated actuators, it is leak-free and maintenance-free, and therefore has a longer service life. Electric linear actuators convert the rotational force of an electric motor into a linear motion. When activated by the electric motor, a worm gear rotates a nut up and down, thus performing the push or pull movement of a piston rod. To supply the electrical components of the backflow preventer with electrical energy, it preferably has a power supply unit via which the backflow preventer can be electrically connected to a power connection element, such as a plug. The power supply unit can, for example, be in the form of a power supply unit, or simply comprise a connection element that allows the connection of a power supply unit. In addition, according to a preferred embodiment, the backflow preventer can comprise at least one emergency power unit equipped with an energy storage device, preferably rechargeable. The emergency power unit is preferably designed and coupled to the backflow preventer in such a way that, in the event of a failure or interruption of the power supply unit, the emergency power unit can automatically and without interruption provide power to the backflow preventer. Specifically, in the event of a power outage, the emergency power unit automatically switches to emergency power operation, ensuring that all electrical components, and thus the automatic backflow preventer, remain functional. Preferably, the backflow preventer further comprises a control unit that includes at least one WLAN and / or LAN module. The control unit can be located outside or inside the backflow preventer's housing and is connected to the electrical components of the backflow preventer, such as the linear actuator, a water level sensor, or a sensor unit, either electrically or wirelessly, for example via WLAN. It essentially controls the movement of the shut-off element by transmitting drive commands to the linear actuator based on detected values. The integrated WLAN and / or LAN module also allows communication with other electrical components of the backflow preventer or the connection of the backflow preventer to a smart home system or a smartphone application. A smartphone application is a software application on the user's smartphone or tablet computer.The smartphone application enables wireless communication between the user and the backflow preventer's control unit, for example, via the integrated Wi-Fi and / or LAN module. The application allows real-time monitoring of the backflow preventer's operating status by receiving messages such as malfunctions or the current position of the shut-off element. A smart home system refers to a central platform that integrates the backflow preventer into the building management system. Ideally, this platform is internet-connected. This allows for automatic monitoring of the operating status and, if necessary, direct control via a smart home interface. As a result, the backflow preventer can be monitored and controlled from any location, status messages and malfunctions are available in real time, and operation is simplified. According to a preferred embodiment of the invention, the backflow preventer comprises at least one (water level) sensor configured for continuously measuring the water level downstream of the backflow preventer. The sensor can, for example, be designed as a contact sensor and can advantageously be installed in the downstream connection fitting or in a wastewater pipe at a position suitable for detecting backflow water. Alternatively, the sensor can also be configured to determine the water level without contact (non-contact sensor). In this embodiment, the sensor operates, for example, as an ultrasonic, radar, or optical sensor that measures the distance to the water surface or the fill level in the wastewater pipe or connection fitting without coming into direct contact with the wastewater.This also allows the sensor to be installed outside the wastewater pipe, for example, on the outer wall of the connection fitting or the wastewater pipe itself. Furthermore, the non-contact sensor can also be installed inside the wastewater pipe or the connection fitting, for example, by enclosing the sensor in a suitable fluid-tight housing. The measured values ​​from the respective sensor are advantageously transmitted to the control unit and evaluated by it, which then controls the linear actuator and thus automatically opens or closes the shut-off element. Thanks to the signal-dependent and automatic control of the linear actuator via the control unit, the backflow preventer can react precisely and as needed to any backflow situations, thus ensuring the highest possible level of protection.Furthermore, the sensor may include or be connected to an acoustic signaling unit, so that in the event of a malfunction an acoustic signal tone is emitted as an alternative or supplement. In an alternative design, the sensor can also be integrated into a sensor unit that includes a signaling unit for emitting an acoustic signal and / or a Wi-Fi and / or LAN module for connecting to the control unit and / or the smart home system and / or the smartphone application. A connection between the sensor unit and the control unit is also possible via an electrical wire / cable. The present invention further relates to a system for monitoring a building's wastewater pipe, comprising the backflow preventer according to the invention and at least one sensor configured for continuously measuring a water level downstream of the backflow preventer. As already explained, the sensor can be a contact sensor, a non-contact sensor, and / or a sensor unit. Furthermore, the present invention relates to a method for operating the backflow preventer according to the invention, comprising the steps of: continuously detecting a water level downstream of the backflow preventer in a wastewater pipe; and automatically triggering a closing process of the shut-off element when a predefined threshold is exceeded; and optionally transmitting the operating status to a smartphone application or a smart home system of a user. According to a preferred further development of the method, the shut-off element can be automatically reopened when the predefined threshold value is undershot, possibly after a predefined time window. This allows the system to restore the flow independently. The closing process of the locking element can preferably be monitored and, in the event of a malfunction, an alarm or status message can be sent in real time to the smartphone application and / or the smart home system via the control unit. This ensures that the user is informed in a timely manner and can then take countermeasures to prevent backflow water from entering the building. According to a preferred further development of the method, events are logged with time and measurement data in the smartphone application and / or the smart home system. This has the advantage of enabling seamless tracking, analysis of operating states, and early detection of anomalies. Within the smartphone application and / or the smart home system, an artificial intelligence or software system can preferably automatically evaluate the measured data from the backflow preventer, such as the water level or the operating state of the backflow preventer. It creates the event log with date and time stamp. In doing so, it recognizes anomalies and irregularities in the operating state or in the measured values, such as deviations in water levels. Based on this, it can display trends and interpret and utilize the log. Character description The invention and its technical context are explained in more detail below with reference to the figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments shown. Unless explicitly stated otherwise, it is also possible, in particular, to extract partial aspects of the matters explained in the figures and combine them with other components and findings from the present description and / or the figures. Furthermore, it should be noted that the figures, and especially the depicted dimensions, are only schematic. The same reference numerals denote the same objects, so that explanations from other figures can be consulted as needed. Figures 1a-c show a first embodiment of the backflow preventer according to the invention in three different views, and Figure 2 shows a second embodiment of the backflow preventer according to the invention in a lateral sectional view. Figures 1a to 1c show a first embodiment of the backflow preventer 1 according to the invention, which is intended for subsequent installation in a wastewater pipe of a building (not shown). Installation can, for example, take place in an existing exposed wastewater pipe to create a central backflow preventer for the entire building. Fig. 1a shows a front view of one side of the backflow preventer 1. This initially comprises a housing 2, which in the present embodiment is approximately cuboid in shape (see Fig. 1c) and essentially has a lower part 3 and an upper part 4. Two adjustable feet 5 are arranged on the lower part 3, by means of which the entire backflow preventer 1 can be positioned securely, as can be seen particularly in Fig. 1c. Although a floor-standing (vertical) installation is preferred, it is not mandatory. The backflow preventer 1 can, in principle, be installed in different positions. For this purpose, corresponding recesses 6 are provided on the adjustable feet 5, by means of which the backflow preventer 1 can be installed on a wall and thus also in a horizontal position. Of course, the recesses 6 can also be used for fixing in a vertical installation.The housing 2 is formed in this case from several plastic parts, such as shells, which are partly glued and / or screwed together. As can be seen in Fig. 1a, the backflow preventer 1 has a flow-through channel 7 in the lower part of the housing 2, the longitudinal axis of which extends into the plane of the drawing. This flow-through channel 7 can be closed in an open- and fluid-tight manner by means of a shut-off element 8 arranged in the housing 2. According to the invention, the shut-off element 8 is displaceable perpendicular to the axial extent of the flow-through channel 7 and can be actuated by a linear actuator 9. The shut-off element 8, which is designed in the form of a disc-shaped body, is thus displaceably mounted in the housing 2 and is located in the lower part 3 in the closed position and in the upper part 4 of the housing 2 in the open position. Figs. 1a and 1b show the shut-off element 8 in a position approximately two-thirds closed.It can be seen that the entire externally visible lower edge region of the shut-off element 8 tapers at an angle. The lower edge region of the shut-off element 8 is thus designed with a conical cross-section, as shown by way of example in Fig. 2. In order to achieve sufficient sealing in the application, the housing 2 includes sealing elements arranged on both sides of the shut-off element 8 in the area of ​​the flow channel 7, which are concealed in the present illustration. Furthermore, the backflow preventer 1 comprises a first tubular connection 10, which is provided for connection to a wastewater pipe (not shown) that may be located upstream of the backflow preventer 1, and a second tubular connection 11, which is provided for connection to a wastewater pipe (not shown) that may be located downstream of the backflow preventer 1 and is accordingly arranged axially opposite the first connection 10 (see Fig. 1c). Ideally, the two connection 10 and 11 have a standardized dimension that is common for wastewater pipes in building installations, for example, 110 mm. As can be seen particularly in Figures 1a and 1b, each of the connection nozzles 10, 11 has a flange-shaped element by which the respective connection nozzle 10, 11 is connected to the housing 2, for example by screw connections. The two connection nozzles 10, 11 are arranged on the lower part 3 of the housing 2 such that their free cross-section is aligned with the flow channel 7 of the housing 2, thus forming a continuous conduit. As previously explained, the shut-off element 8 can be actuated by a linear actuator 9. This actuator is designed as an electric linear drive and, in the present embodiment, is arranged on the outside of the upper part 4 of the housing 2, as can be seen in Figures 1a and 1c. The connection to the shut-off element 8 is made by a coupling element 12, which in this case is designed in the form of a clamp. This clamp is detachably connected on one side to the piston rod 13 of the linear actuator 9 and on the other side to a handle 14 of the shut-off element 8. The handle 14 is located at a distal end of a piston rod 15 of the shut-off element 8 (see Figure 1c). This embodiment thus allows for both automatic and manual opening and fluid-tight closing of the shut-off element 8. Furthermore, in the present embodiment, the backflow preventer 1 has a smart home-enabled control unit 16 and a sensor unit 17, which are also arranged on the outside of the upper part 4 of the housing 2. The sensor unit 17 is connected to the control unit 16 via an electrical line / cable. The control unit 16 is a device that, in the present embodiment, combines several components. It essentially comprises a power supply unit, a WLAN module, and a relay switch, all arranged on a circuit board 18. Furthermore, it can include a position detection unit, which can be used, in particular, to detect the closing process of the locking element 8. In this embodiment, the sensor unit 17 comprises a sensor 19, which is configured for continuously measuring a water level, advantageously downstream of the backflow preventer 1, and a signal unit 20, which can emit an acoustic signal. For the purpose of installing the sensor 19, it is sufficient if it is installed, for example, in the corresponding connection stub 10, 11 or in a wastewater pipe (not shown) at a position suitable for detecting backflow water. It can be seen that the sensor 19 is connected to the sensor unit 17 via an electrical line / cable. The operating function of the backflow preventer 1, which is powered by electricity, is as follows. As soon as the sensor 19 downstream of the backflow preventer 1 detects a predefined backflow water level in the wastewater pipe, it transmits a signal to the control unit 16. The control unit 16 then activates the linear actuator 9, causing the shut-off element 9 to close the flow-through channel 7. The user is informed of this in real time via the smart home connection, for example, by SMS, email, or directly via the smartphone application. Should a malfunction occur during the closing process, for example, because the shut-off element 8 is blocked due to contamination and cannot seal the flow-through channel 7 fluid-tight, this condition is also detected by the control unit 16 and communicated to the user, preferably in real time.The user can then take appropriate countermeasures. The shut-off element 8 can also be automatically reopened if the backflow water level falls below a predefined threshold, and possibly after a predefined time window, with the user being notified of this condition in the same way. To ensure the functionality of the backflow preventer 1 in the event of a power failure, the backflow preventer 1 in the present embodiment additionally has an emergency power unit 21, which is equipped with a suitable energy storage device, for example, commercially available primary and / or secondary batteries. As shown in Fig. 1b, the emergency power unit 21 is also located on the outside of the upper part 4 of the housing 2 and is connected to the control unit 16 via an electrical line / cable. Figure 2 shows a further embodiment of the backflow preventer 1 in a side sectional view. In contrast to the previous embodiment, the linear actuator 9, the control unit 16, and the emergency power unit 21 are arranged inside the housing 2. The two connection ports 10, 11 are also integral components of the housing 2. In this embodiment, neither an acoustic signal unit 20 nor a handle 14 is present. The illustration particularly shows the two sealing elements 22, 23, which are seated in corresponding recesses of the flow channel 7. It can be seen that the lower recess, which faces the lower edge region of the shut-off element 8, is wider, and the sealing element 22 is located in this area only on the upstream side. It can also be seen in the illustration that the lower edge region of the shut-off element 8 has a tapered cross-section. This may result in...During the closing process, dirt particles accumulated in the lower recess are moved from the contact area into the available clearance space of the wide recess by the shut-off element 8. A sensor 19 is also visible, positioned at the 12 o'clock position on the inner wall of the connection nozzle 11. This sensor is designed as a non-contact sensor. To prevent it from coming into contact with the wastewater, it is enclosed in a fluid-tight housing. Reference symbol list 1 Backflow preventer 2 Housing 3 Lower part of the housing 4 Upper part of the housing 5 Adjustable feet 6 Recesses 7 Flow-through channel 8 Shut-off element 9 Linear actuator 10 Connection spigot 11 Connection spigot 12 Coupling element / clamp 13 Linear actuator piston rod 14 Handle 15 Shut-off element piston rod 16 Control unit 17 Sensor unit 18 Circuit board 19 Sensor 20 Signal unit 21 Emergency power unit 22 Sealing element 23 Sealing element QUOTES INCLUDED IN THE DESCRIPTION This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature DE 20 2007 017 945 U1

[0004]

Claims

Backflow preventer (1) for installation in a wastewater pipe, in particular for use in a wastewater pipe of a building, comprising: a housing (2) with a flowable channel (7) which can be closed openly and fluid-tight via at least one shut-off element (8); a first tubular connection spigot (10) which is provided for connection to a wastewater pipe arranged upstream of the backflow preventer (1), and a second connection spigot (11) which is provided for connection to a wastewater pipe arranged downstream of the backflow preventer (1), wherein the two connection spigots (10, 11) are arranged on the housing (2) such that they form a continuous pipe with the flowable channel (7); characterized in that the shut-off element (8) is displaceable perpendicular to the axial extent of the flowable channel (7) and can be actuated via a linear actuator (9). Backflow preventer (1) according to claim 1, characterized in that the shut-off element (8) is arranged in the housing (2) between the two connection spigots (10, 11). Backflow preventer (1) according to one of claims 1 or 2, characterized in that the shut-off element (8) is arranged at least in the area of ​​the flow channel (7) of the housing (2) between two sealing elements (22, 23). Backflow preventer (1) according to claim 3, characterized in that the sealing elements (22, 23) are designed in the form of an elastic profile seal. Backflow preventer (1) according to one of the preceding claims, characterized in that the shut-off element (8) is completely enclosed in the housing (2). Backflow preventer (1) according to one of the preceding claims, characterized in that the shut-off element (8) comprises a handle (14) by means of which the shut-off element (8) can be manually opened and closed in a fluid-tight manner. Backflow preventer (1) according to one of the preceding claims, characterized in that the linear actuator (9) is arranged inside the housing (2) and is completely enclosed by it. Backflow preventer (1) according to one of the preceding claims 1 to 6, characterized in that the linear actuator (9) is arranged outside the housing (2). Backflow preventer (1) according to one of the preceding claims, characterized in that it further comprises a power supply unit via which the backflow preventer (1) can be electrically connected to a power connection element. Backflow preventer (1) according to one of the preceding claims, characterized in that it further comprises at least one emergency power unit (21) which is provided with an energy storage device, preferably rechargeable, wherein the emergency power unit (21) is preferably designed and coupled to the backflow preventer (1) in such a way that in the event of a failure or interruption of the power supply unit, the energy supply of the backflow preventer (1) can be provided automatically and without interruption by the emergency power unit. Backflow preventer (1) according to one of the preceding claims, characterized in that it comprises a control unit (17) which has at least one WLAN and / or LAN module (12). Backflow preventer (1) according to one of the preceding claims, characterized in that the linear actuator (9) provided for actuating the shut-off element (8) is optionally designed as an electric, hydraulic or pneumatic actuator. Backflow preventer (1) according to one of the preceding claims, characterized in that it comprises at least one sensor (19) which is configured to continuously measure a water level downstream of the backflow preventer (1). Backflow preventer (1) according to claim 13, characterized in that the sensor (19) is configured in such a way that it can determine the water level without contact. Backflow preventer (1) according to one of the preceding claims 11 to 14, characterized in that the control unit (16) can be connected to a smartphone application and / or a smart home system via a network protocol. System for monitoring a wastewater pipe of a building, comprising a backflow preventer (1) according to one of the preceding claims 1 - 12 and at least one sensor (19) which is configured to continuously measure a water level downstream of the backflow preventer (1). Method for operating a backflow preventer (1) according to any one of the preceding claims 1 to 15, comprising the steps: continuously detecting a water level downstream of the backflow preventer (1) in a wastewater pipe; and automatically triggering a closing process of the shut-off element (8) when a predefined threshold is exceeded; and optionally transmitting the operating status to a smartphone application or a smart home system of a user. Method according to claim 17, characterized in that the shut-off element (8) is automatically reopened when the predefined threshold value is undershot, possibly after a predefined time window. Method according to one of claims 17 or 18, characterized in that the closing process of the locking element (8) is monitored and in the event of a malfunction an alarm or status message is sent in real time to the smartphone application and / or the smart home system via the control unit. Method according to one of the preceding claims 17 to 19, characterized in that event logging with time and measurement data takes place in the smartphone application and / or the smart home system.

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