EP2489800B1 - Waste water hoisting facility - Google Patents

Description

The invention relates to a wastewater lifting plant with the features specified in the preamble of claim 1.

Wastewater lifting plants are used to raise sewage, which is at a level below a sewer, to the level of the sewer system. In this case, sewage lifting plants are known, which have a container in which flows in the water to be lifted. In the container or on the container at least one pump is arranged, which then pumps the wastewater from the container to the desired higher level. To be able to switch the at least one pump on and off as needed, a level sensor is arranged on or in the container, which detects the water level in the interior of the container and the pump on and off depending on the water level.

The problem with these sewage lifting systems is that the fill level sensor can be impaired in its function by impurities which are carried in the wastewater.

WO 03/07113 A1 discloses a submersible pump with a level switch, wherein the level switch has a housing provided for immersion in the liquid, in which a pressure sensor is arranged and which is closed to the liquid through a membrane. About pressure changes inside the housing, the fluid level is detected.

US 5,152,670 discloses a sewage collection tank with a pump and a pressure sensor designed as a level sensor, which has a membrane towards the liquid, in the displacement of an electrical contact is actuated. A corresponding level switch is off US 2,922,002 known, which discloses a submersible pump with such a pressure switch.

In view of the prior art, it is an object of the invention to provide an improved wastewater lifting plant, which has an improved level sensor with improved reliability.

This object is achieved by a sewage lifting plant having the features specified in claim 1. Preferred embodiments emerge from the subclaims, the following description and the accompanying figures.

Like known sewage lifting plants, the sewage lifting plant according to the invention also has a container which is provided with at least one drain opening. At this inlet opening an input-side sewer line can be connected, through which flow to be lifted wastewater in the Behölter. At least one pump is arranged on or in the container, which is suitable for pumping the wastewater out of the container to a higher level. For switching on and off the pump as a function of the water level in the container, a level sensor is arranged in the container. The level sensor is designed so that it turns on the pump when it reaches a predetermined level and the pump turns off when falling below this level or upon reaching a second predetermined lower water level.

According to the invention, the filling level sensor has a preferably completely closed membrane housing arranged in the container, which has a movable membrane in one of its housing walls. This membrane forms the actual sensor element. The membrane housing with the membrane is arranged so that the membrane is immersed in the water in the container at least on reaching the water level at which the pump is to be switched on. Since the membrane housing with the membrane then displaces part of the liquid or of the wastewater, a pressure is exerted by the waste water on the membrane housing and thus the membrane from the outside, which leads to a movement or deformation of the movable membrane. Inside the diaphragm housing, the diaphragm is coupled to at least one sensor or switch for switching the pump on and off. Thus, the movement or the deformation of the membrane is transmitted to the at least one switch such that the movement or deformation of the membrane a switching operation of the Switch causes. Alternatively, a sensor may be provided which detects the deformation or movement of the membrane and then optionally via an intermediate control device which evaluates the sensor signal, the pump on and off.

The configuration of the fill level sensor in this way has the advantage that the actual sensor or switch components are arranged in the interior of the membrane housing, which is completely closed to the interior of the container in which the wastewater is located. Thus sensor and switch inside the membrane housing do not come into contact with the waste water. This protects these components against contamination and moisture. In particular, so the electrical components are protected from contact with water and moisture. But also moving mechanical parts of the switch are so protected from the sewage and impurities. With the wastewater comes only the outside of the housing wall and the movable membrane in contact. However, these are smooth surfaces which are insensitive to contamination. The membrane is also affected by impurities on the outside usually not in their mobility. This creates a reliable, robust level sensor with a high level of operational reliability.

The membrane is preferably arranged on the lower side of the membrane housing. Thus, this first dips into the water and is pressurized by the waste water and the water displacement, so that it then comes to the detectable movement or deformation of the membrane.

According to a preferred embodiment, the membrane is detachable, preferably connected via a bayonet coupling with the membrane housing. Thus, the membrane housing by removing the Membrane are opened, for example, to carry out repair or maintenance work inside the diaphragm housing. In addition, the membrane can be easily replaced, for example, if it is damaged or in their mobility, z. B. is affected by aging. The membrane is preferably sealed with the other housing walls of the diaphragm housing in plant. For this purpose, a separate sealing element may be provided which comes to rest between the membrane and a surrounding housing wall. Depending on the material of the membrane used, however, the membrane itself can serve as a seal. It is also possible to form a suitable seal directly on the surrounding housing wall.

As described above, the membrane housing with the membrane is expediently designed and arranged in the interior of the container such that, during operation of the sewage lifting system, the membrane is located vertically below a maximum water level in the container. In this case, the maximum water level in the container is that water level, which occurs in normal operation as the maximum water level and makes an Enschalt the pump required. However, it is also conceivable to design and arrange the membrane housing with the membrane in such a way that even at a lower water level, which does not require the pump to be switched on, the membrane dips into the water. As the water level continues to increase, the pressure on the outside of the diaphragm housing and diaphragm increases, causing the diaphragm to deform more or less, and only when this greater deformation or movement activates a switch or sensor inside the diaphragm housing to turn on the pump.

In the interior of the membrane housing, in one preferred embodiment, an actuating element is arranged such that it transmits a movement of the membrane to a switch. This actuator may be a mechanical component, which transmits the movement of the membrane, for example, to a switch contact of the switch. For example, at least one lever or a lever system for transmitting movement can be arranged in the interior of the diaphragm housing between the diaphragm and the switch.

According to a further preferred embodiment, at least one receptacle for one or more weight element is formed on the membrane or a component coupled to the motion of the membrane. With the help of these weight elements, the level at which a switching operation of the switch is to be executed can then be set. If the membrane is loaded from the inside of the membrane housing with a weight force caused by one or more weight elements, a corresponding higher external force acting on the membrane force is required to deform or move the membrane. Ie. it is a greater external pressure acting on the membrane water pressure and thus a higher water level required to move the membrane and thus perform a switching operation.

According to a further preferred embodiment, the membrane and the components coupled to it are configured such that they experience buoyancy in the water. By arranging weight elements on the membrane or on the components coupled thereto with movement, a weight force opposing this buoyancy can be exerted on the membrane, so that a greater buoyancy, ie, movement, of the membrane and thus causing a switching process. H. a larger water pressure acting on the membrane is required.

For this purpose, at least one weight element is provided, which is detachably fastened to the receptacle. By selectively arranging this weight element can thus the switching threshold or the water level in the container, where the switch is to turn on the pump, to be changed. Optionally, several or different weight elements may be provided for selectively attaching to the recording.

The membrane housing is connected at its upper end to a sensor housing in which the switch or the sensor is arranged. The switch or the actual sensor, which detects the movement of the membrane, can additionally be additionally encapsulated in the sensor housing. Ie. the sensor housing can be separated from the diaphragm housing, for example by a closed wall. According to the invention, the motion transmission or motion detection is performed by a closed wall of the sensor housing. This is done according to the invention magnetically.

The membrane housing is preferably detachable, more preferably connected via a bayonet coupling with the sensor housing, optionally a seal can be arranged between the membrane and sensor housing. This may optionally be formed integrally with the diaphragm housing or the sensor housing. The detachable connection allows easy installation and easy disassembly for maintenance or repair purposes.

More preferably, the membrane housing is closed at its upper end by the sensor housing. Thus, a closed volume of air is formed in the membrane housing, which serves the displacement of water during immersion of the membrane housing in the water. The fact that the membrane housing is closed by the sensor housing at the top, it is reliably prevented that water can penetrate into the interior of the diaphragm housing. Penetrating water would impair or block the function of the sensor. Such an intrusion would be for example at a full run of the container, to be feared for example in case of failure of the pump.

Furthermore, the sensor housing is designed to be closed relative to the diaphragm housing and a magnetic coupling is provided between the sensor or switch in the sensor housing and the diaphragm or an actuating element arranged in the diaphragm housing in motion-coupled with the diaphragm. This embodiment makes it possible to form the sensor housing completely sealed relative to the diaphragm housing, in particular by means of a closed wall of the sensor housing. The magnetic coupling makes it possible to detect the movement or deformation of the membrane through the closed wall. For this purpose, a first magnet can be arranged on the membrane or a component coupled to the motion of the membrane, the position of which is changed during movement of the membrane. This change in position of the magnet can be detected by a sensor, for example a reed contact in the interior of the sensor housing through the wall of the sensor housing, provided that the magnet and the magnetic sensor, ie, for example, the reed contact, are arranged in the vicinity of the wall of the sensor housing. Thus, the magnet and the magnetic field detecting sensor are arranged so that the magnetic field affects the sensor at least when a switching operation is to take place. Instead of arranging a sensor to be detected in the interior of the sensor housing, at least one second magnet, which is movable by the first magnet, may be arranged in the interior of the sensor housing. This second magnet can then directly or indirectly via other moving components with a switch or sensor inside the sensor housing be coupled. Thus, the second magnet can actuate by its movement a switch or switch contact, via which then the pump is switched on or off. In this case, such a switch or Schaltkotakt directly turn on or off the pump or it may be interposed a control device which detects the switch signal and then controls the pump accordingly.

Particularly preferably, the entire level sensor is designed as an assembly inserted into an opening of the container. This allows for easy installation, since the pre-assembled level sensor can be inserted into the opening of the container. Furthermore, the entire level sensor for maintenance and repair work can be easily removed from the container. In this case, the level sensor then releases the opening, which then allows access to the interior of the container in order to carry out further repair or maintenance work there, for example. Preferably, a seal is arranged between the level sensor and the surrounding wall of the container, so that when inserted level sensor, the opening is sealed. This prevents water from spilling out of the opening in the event that the container is completely full.

More preferably, the sensor housing is fixed in or at the opening of the container. Also, the sensor housing may be bolted to the container surrounding the wall opening. Alternatively, a bayonet coupling would be conceivable. Particularly preferably, the opening is provided surrounding the container wall, a thread into which the sensor housing is screwed with a corresponding thread.

Fig. 1

eine Explosionsansicht einer erfindungsgemäßen Abwasserhebeanlage,

Fig. 2

eine perspektivische Ansicht des Füllstandsensors der in Fig. 1 gezeigten Abwasserhebeanlage,

Fig. 3

einen Längsschnitt durch den Füllstandsensor gemäß Fig. 2 entlang der Linie III-III in Fig. 4,

Fig. 4

eine Draufsicht auf den Füllstandsensor gemäß Fig. 2 und 3 bei geöffneten Sensorgehäuse und

Fig. 5

eine Schnittansicht durch den Füllstandsensor gemäß der Figuren 2 bis 4 entlang der Linie V-V in Fig. 4.

The invention will now be described by way of example with reference to the accompanying drawings. In these shows:

Fig. 1

an exploded view of a wastewater lifting plant according to the invention,

Fig. 2

a perspective view of the level sensor of in Fig. 1 sewage lifting plant shown,

Fig. 3

a longitudinal section through the level sensor according to Fig. 2 along the line III-III in Fig. 4 .

Fig. 4

a plan view of the level sensor according to Fig. 2 and 3 with open sensor housing and

Fig. 5

a sectional view through the level sensor according to the FIGS. 2 to 4 along the line VV in Fig. 4 ,

The efestungsgemäße wastewater lifting plant has a container 2, which is preferably made of plastic. The container 2 has in at least one wall at least one inlet opening 4, to which an input-side sewer line can be connected, through which wastewater flows into the interior of the container 2. In the container 2, a pump 6 is also provided. The pump 6 serves to pump the waste water from the container 2 via the outlet line 7 arranged in the container and the outlet connection 8 provided in the container 2 into a pressure or wastewater line connected to the outlet connection 8. At the top 10 of the container 2, an opening 12 is formed, in which a level sensor 14 is inserted. This level sensor 14 is based on the FIGS. 2 to 5 described in more detail. The level sensor 14 has at its upper end a sensor housing 16, which is inserted into the opening 12. On the wall of the opening 12 it comes with the seal 18 sealingly to the plant. Starting from the sensor housing 16, a tubular membrane housing 20 extends in the vertical direction X down. The membrane housing 20 is at its lower open end closed by a movable or deformable membrane 22. The membrane 22, which may be formed of an elastomeric material, for example, is fixed by a retaining ring 24 at the lower end of the tubular membrane housing 20. The retaining ring 24 surrounds the membrane housing 20 circumferentially and is releasably fixed to the membrane housing 20 with a bayonet coupling. By removing the retaining ring 24 from the membrane housing 20, the membrane 22 can be removed from the membrane housing 20. The membrane 22 is positively fixed or clamped between the diaphragm housing 20 and the retaining ring 24. At the same time, the membrane 22 with its circumferential thickening 26 simultaneously forms a seal, with the result that the membrane 22 tightly seals the membrane housing 20 at the bottom.

At the top, the diaphragm housing 20 is closed by the sensor housing 16. The sensor housing 16 engages in the upper axial end of the diaphragm housing 20. Between the sensor housing 16 and the diaphragm housing 20, a sealing ring 28 is arranged for sealing. In this way, an enclosed volume of gas or air is defined inside the membrane housing 20.

In the interior of the diaphragm housing 20, a vertically extending actuating rod 30 is arranged, which has at its lower end a plate-shaped extension 32 which rests flat against the inside of the membrane 22. Here it is sufficient that the plate-shaped extension 32 rests loosely on the membrane 22. Alternatively, it is also conceivable that they are firmly connected to each other, for example, glued together.

At its upper end, the actuating rod 30 is guided in a vertically extending sleeve 34 in the sensor housing 16. The sleeve 34 is completely closed to the sensor housing 16 and forms part of a wall of the sensor housing 16, so that the interior of the sleeve 34 is sealed by the wall of the sleeve relative to the interior 36 of the sensor housing 16. In this case, the sleeve 34 is in this example in one piece with the wall 38 of the sensor housing 16 abgeitdet, which forms the underside of the sensor housing 16, which seals the end face of the diaphragm housing 20.

The actuating rod 30 carries at its upper end, which hineinerstreckt into the sleeve 34, a permanent magnet 42. The permanent magnet 42 is movable with the actuating rod 30 in the vertical direction X in the sleeve 34.

Inside the sensor housing 16, the electrical switch 44 is arranged. The electric switch 44 can be actuated via a fork-shaped arm 46, which can be pivoted about a pivot axis 48 in the horizontal plane. The two legs 50 of the fork-shaped arm do not extend parallel but at an acute angle to each other. The two legs 50 each carry a permanent magnet, one leg 50 the permanent magnet 52 and the other leg 50, the permanent magnet 54. The arm 46 with the legs 50 is configured and pivotable about the pivot axis 48 that in the in Fig. 4 and 5 shown rest position of the permanent magnet 52 is located on the AuBenwandung the sleeve 34. In the second pivot position of this permanent magnet 52 is removed from the sleeve 34 and the second permanent magnet 54 is located on the opposite outer side of the sleeve 34th

The actuating rod 30 is so movable with its permanent magnet in the sleeve 34 that, when the actuating rod 30 moves vertically upward, its permanent magnet 42 is moved between the permanent magnets 52 and 54. In this case, the permanent magnet 54 is arranged so that its magnetic south pole faces the magnetic north pole of the permanent magnet 42. The permanent magnet 52 is arranged exactly the opposite, so that its magnetic South pole facing the south pole of the permanent magnet 42. This causes that, when the permanent magnet 42 is displaced vertically by moving the operating rod 30 between the permanent magnets 52 and 54, the permanent magnet 54 is attracted to the permanent magnet 42, while the permanent magnet 52 is repelled by the permanent magnet 42. This leads to a pivoting of the fork-shaped arm 46 about the pivot axis 48 and thus to an actuation of the electrical switch 44. When the permanent magnet 42 is again moved out of the gap between the permanent magnets 52 and 54 in the vertical direction, the arm moves 46, for example, by the restoring force of a spring, not shown here in the in Fig. 4 and 5 shown initial position, whereby the switch 44 is moved back to its first switching position. The operation of the switch 44 can be used to turn on and off the pump. It is advantageous that all electrical components of the electrical switch 44 are arranged in the interior of the sensor housing 16 and the sensor housing 16 is formed completely closed, since no moving components have to be led out of this. The motion is transmitted magnetically through the wall of the sensor housing 16, ie through the wall of the sleeve 34 therethrough.

The operation of the level sensor shown is such that the level sensor is arranged in the container 2, that its lower end, ie the membrane 22 is located at least below an upper water level 56, so that the membrane 22 is immersed in the water. In the process, the membrane housing 20 with the membrane 22 displaces the water in the submerged area, whereby a pressure acting vertically upward on the membrane 22 is generated. This pressure causes the membrane 22 to move upwardly in the vertical direction X, thereby pushing the actuating rod 30 vertically upward, so that the permanent magnet 42 between the permanent magnets 52 and 54 is moved and causes the previously described switching operation. When the water level 56 decreases, the pressure on the diaphragm 22 decreases again from the outside and the diaphragm 22 moves downwards again due to the internal pressure inside the diaphragm housing 20 and the weight force of the actuating rod 30, so that the permanent magnet 42 again turns vertically downwards the space between the permanent magnet 52 and 54 is moved out.

In order to adjust the pressure and thus the water level 56, in which a switching operation is caused by movement of the diaphragm 22, a receptacle 58 is formed at the lower end of the actuating rod 30 above the plate-shaped extension 32, on which weight elements 60 can be arranged. The weight elements 60 are ring-shaped, can be pushed onto the actuating rod 30 from above and are fixed in the receptacles 58 via latching hooks 62. The weight elements 60 may be formed, for example, as annular discs made of metal. The weight force generated by the weight elements 60 counteracts the water pressure acting from below on the membrane 22. In this way can be adjusted by adjusting the weight of the pressure at which the membrane 22 moves with the actuating rod 30 upwards. In this way, the switching threshold or water level 56 can be defined, in which the pump is turned on by the permanent magnet between the permanent magnets 52 and 54 is moved.

LIST OF REFERENCE NUMBERS

2

- Container

4

- inlet opening

6

- pump

7

- outlet pipe

8th

- outlet connection

10

- top

12

- opening

14

- Level sensor

16

- Sensor housing

18

- Poetry

20

- Diaphragm housing

22

- membrane

24

- retaining ring

26

- thickening

28

- sealing ring

30

- Operating rod

32

- plate-shaped extension

34

- Sleeve

36

- Inner space

38

- wall

42

- permanent magnet

44

- electrical switch

46

- Poor

48

- Swivel axis

50

- thighs

52, 54

- permanent magnet

56

- water level

58

- Admission

60

- Weight elements

62

- locking hook

X

- vertical direction

Claims (12)

1. A waste water lifting installation with a container (2), a pump and a level sensor (14) arranged in the container (2), wherein the level sensor (14) comprises a closed membrane housing (20) which is arranged in the container (2) and which in a housing wall comprises a movable membrane (22), and wherein the membrane (22) in the inside of the membrane housing (20) is coupled to at least one sensor or switch (44) for switching the pump on and off, characterised in that that the membrane housing (20) at its upper end is connected to a sensor housing (16), in which the switch (44) or the sensor is arranged, wherein the sensor housing (16) is designed in a closed manner with respect to the membrane housing (20), and a magnetic coupling is provided between the sensor or switch (44) in the sensor housing (16) and the membrane (22) or an actuation element (30) which is coupled in movement to the membrane (22) and which is arranged in the membrane housing (20).
2. A waste water lifting installation according to claim 1, characterised in that the membrane (22) is arranged on the lower side of the membrane housing (20).
3. A waste water lifting installation according to claim 1 or 2, characterised in that the membrane (22) is connected to the membrane housing (20) in a releasable manner, preferably via a bayonet coupling.
4. A waste water lifting installation according to one of the preceding claims, characterised in that the membrane housing (20) with the membrane (22) is designed and arranged in the container (2), in a manner such that the membrane (22) is situated vertically below a maximal water level (56) in the container (2), on operation of the waste water lifting installation.
5. A waste water lifting installation according to one of the preceding claims, characterised in that an actuation element (30) is arranged in the inside of the membrane housing (20) in a manner such that it transmits a movement of the membrane (22) onto the switch (44).
6. A waste water lifting installation according to one of the preceding claims, characterised in that at least one receiver (58) for one or more weight elements (60) is formed on the membrane (22) or on a component (30) which is coupled in movement to the membrane (22).
7. A waste water lifting installation according to one of the preceding claims, characterised in that the membrane (22) and the components (30) which are coupled in movement to it, are designed in a manner such that they experience a buoyancy in water.
8. A waste water lifting installation according to claim 6, characterised in that at least one weight element (60) is provided, which is releasably fastenable on the receiver (58).
9. A waste water lifting installation according to one of the preceding claims, characterised in that the membrane housing (20) is releasably connected to the sensor housing (16), preferably via a bayonet coupling.
10. A waste water lifting installation according to one of the preceding claims, characterised in that the membrane housing (20) at its upper end is closed by the sensor housing (16).
11. A waste water lifting installation according to one of the preceding claims, characterised in that the level sensor (14) is designed as a construction unit which is inserted into an opening (12) of the container (2).
12. A waste water lifting installation according to claim 11, characterised in that the sensor housing (16) is fastened in or on the opening (12) of the container (2).

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