EP0649946B1 - Process for actuating a shut-off valve and a control system for actuating such a valve - Google Patents

Description

The invention relates to a method for actuating a shut-off valve and Control arrangement for actuating one according to the preambles of the subordinate ones Claims 1 and 5.

To keep the water clean, it is necessary that the wastewater in sewage treatment plants reached. However, this is often due to the disproportionately high cost of conventional ones Sewer systems or because of difficult local conditions such as lack of natural Slope, low settlement density, unfavorable subsoil and crossing one Water protection area not possible. But even for such problem cases there is the possibility to carry out a sewage treatment plant disposal if a vacuum drainage or "Vacuum sewerage" is used.

A corresponding vacuum sewer system comprises house connection shafts as essential components with a currentless control arrangement and shut-off or suction valves, a subsequent piping system with systematically arranged high and low points as well as a vacuum station with waste water collection tanks, waste water pumps, Vacuum pumps, measurement and control technology.

In order to promote the wastewater, it first flows out of buildings via standard free fall house connection lines to a e.g. on a plot of land located in the the exclusively pneumatically controlled shut-off valves and the associated control arrangement are accommodated.

Due to the mechanism present in the control arrangement, a specified back pressure the shut-off valve is opened and the waste water in the vacuum line aspirated. Depending on the time, the valve closes via spring force and after a few seconds Vacuum.

The wastewater itself collects at the lowest points in the pipe system and is used by air flowing in gradually over the following high points towards the Vacuum station pushed. The vacuum tank will then become that Wastewater with conventional wastewater pumps via a pressure and free fall line Wastewater treatment plant funded.

The control arrangement assigned to the shut-off valve should be adapted automatically the wastewater portions to be extracted and the operating conditions in the drainage system enable.

A control arrangement of the type described in the introduction is known as "AIRVAC" known. The time is controlled via the pressure-adjustable chamber, which starts with Atmospheric pressure is applied. A clear OPEN / CLOSE position of the negative pressure the shut-off valve conducting second valve is not given. This means that the crowd of the waste water or waste water / air mixture per opening stroke of the shut-off valve is clearly defined. This can lead to malfunctions, particularly in the case of large amounts of wastewater to lead. It is also disadvantageous that the suction time from the existing negative pressure in an unfavorable manner for the entire system because of the opening times are in turn dependent on the prevailing negative pressure.

Another disadvantage is that an opening of the negative pressure to the shut-off valve opens second valve can be done with a low vacuum, but not to Suck off is sufficient. This increases the risk that waste water in the frost area of the Pipe raised and freeze there.

DE 37 27 661 A1 discloses a pneumatic control device for a shut-off valve a vacuum sewer known. To make an accurate setting and reliable Ensuring the function of the control device is next to one of a dynamic pressure actuated first valve and a structurally complex time control device at least a control valve and a minimum vacuum valve are necessary.

Due to the complex mechanical structure, in particular the timing device, which is under another a membrane piston with a hollow pin, which is guided in a guide bush, includes to open or close the control valves is a complex construction or assembly required.

DE 38 23 515 A1 describes a suction gun, from which a collecting container Wastewater can be sucked off using negative pressure. In addition to one in a vacuum line, through which the wastewater is sucked off, existing and closing or opening Exhaust valve requires a control valve that can be operated manually or automatically. So that the control valve can be closed when the vacuum drops, which means that Shutoff valve is separated from the vacuum and thus the vacuum line is shut off can be, the control valve has a valve piston, depending on the Position of the valve piston act axially and / or radially spring-loaded balls to Closing the control valve are necessary.

The present invention is based on the problem of a method and a control arrangement of the type described above so that in a compact and structurally simple Building a high level of operational security is guaranteed, essentially one vacuum-independent time control takes place, d. that is, after the back pressure has ceased to exist Control arrangement the vacuum supply to the shut-off valve according to a defined Period closes. It should also be ensured that the negative pressure to Shut-off valve controlling valve always assumes a defined position with a negative pressure, which ensures that waste water can be sucked off via the shut-off valve.

According to the invention, the problem is essentially solved by the subordinate claims resolved characteristics to be removed. Further training results from the subclaims.

According to the invention there is a clear OPEN / CLOSE position of the vacuum to the Shutoff valve conducting second valve. As a result, the position of the shut-off valve is clear Are defined.

The suddenly changing state (OPEN / CLOSE or CLOSE / OPEN) of the valve is indicated by so-called adjustable limiter, which acts as on the valve piston of the second valve act on spring-loaded balls in the manner described below. there the spring force can be adjusted to only enter at previously defined vacuum values Allow opening or closing of the second valve or control valve. This is ensures that the wastewater can only be lifted out of the storage space, if there is sufficient vacuum for suction. Consequently, in the frost area there is no waste water in the line leading to the shut-off valve.

Alternatively, the suddenly changing state can be reactivated by means of a magnet are, the forces acting directly or indirectly on the second valve then change spontaneously when the specified pressure conditions occur.

The spring element acting on the valve piston of the second valve can be a spring be arranged in the pressure-adjustable chamber or its area and restoring forces exerts on the valve piston.

Alternatively, restoring forces can also be generated by a membrane attached in the chamber are caused, which is connected to the valve piston. The main task of such However, the diaphragm is pressurized from one via the first valve to the chamber Vacuum connectable first area to separate from a second area, which is always only is essentially subjected to atmospheric pressure. At the same time, the membrane exercises Guide function for the valve piston.

In an embodiment it is provided that the first and second valve are in a cylindrical, Connections for the dynamic pressure and the vacuum as well as a connection to the shut-off valve having housing are arranged, wherein the valve piston of the second valve in one first housing section is guided.

In order to enable a sudden changeover, the valve piston can be in the first axially displaceably receiving housing section acting radially on the valve piston and elements that snap into it when the valve is closed or open as a limiter be arranged. In particular, however, it is provided that the valve piston with the second valve connected membrane by means of a magnet in a first position held or when there is a predetermined pressure change in the chamber or its area abruptly or largely abruptly from the first position to a second position or can be reversed, with the second valve the vacuum connection in the first position to the shut-off valve and in the second position the vacuum connection releases to the shut-off valve.

In order to be able to equalize the pressure in the shut-off valve, proposed that the housing opening with the valve piston of the second valve Receiving first housing section is connected and when closed, the Vacuum to the shut-off valve blocking position of the second valve over the housing section pressure is connected to the shut-off valve.

Further details, advantages and features of the invention result not only from the Claims, the features to be extracted from them - individually and / or in combination - but also from the following description of one of the drawings preferred embodiment.

Fig. 1

eine Prinzipdarstellung einer ersten Ausführungsform einer Kompaktsteueranordnung bei fehlendem Staudruck,

Fig. 2

die Kompaktsteueranordnung nach Fig. 1 nach Vorliegen eines Staudruckes,

Fig. 3

die Kompaktsteueranordnung nach Fig. 1 und Fig. 2, bei der über ein Ventil eine Verbindung zu einem Absperrventil eines Unterdruck-Abwassersystems herstellbar ist,

Fig. 4

die Kompaktsteueranordnung nach Fig. 3, jedoch nach Wegfall des Staudruckes, und

Fig. 5

eine zweite Ausführungsform einer Kompaktsteueranordnung.

Show it:

Fig. 1

1 shows a basic illustration of a first embodiment of a compact control arrangement in the absence of a dynamic pressure,

Fig. 2

1 after the presence of a dynamic pressure,

Fig. 3

1 and 2, in which a connection to a shut-off valve of a vacuum sewage system can be established via a valve,

Fig. 4

the compact control arrangement according to FIG. 3, but after the back pressure has been eliminated, and

Fig. 5

a second embodiment of a compact control arrangement.

1 to 4 and 5 is purely in principle the structure and function of the invention Compact control arrangement (10) intended for a shut-off valve which can be actuated by vacuum for a vacuum sewage system.

The compact control arrangement (10), which operates without current but pneumatically, consists of a cylindrical housing (12) in which a first valve (14) or trigger valve, which has a Membrane (16) from a dynamic pressure reaching through an opening (18) of the housing (12) can be acted upon, and a second valve or control valve (20) are arranged. The valves (14) and (20) are with their valve pistons (22) and (24) along the longitudinal axis of the housing (12) arranged.

The valve piston (24) of the control valve (20) is in a bore (26) in an intermediate floor (28) of the housing (12) is added. This acts radially on the outer surface of the valve piston (24) preferably three spring-biased offset by 120 ° to each other Balls, of which, for reasons of simplification, in principle two balls (30), (32) are drawn, which can also be called snap balls, and which in the End positions of the valve (20), i.e. when the valve (20) is closed (FIGS. 1 and 2) or open valve (20) (Fig. 3 and 4) engage in radially circumferential annular grooves (34) and (36). The actuating elements (38) and (40) act on the balls (30) and (32) Spring force changeable.

The ball snappers (30) and (32) exercise the function of limiters in such a way that in the manner described below, the valve (20) abruptly from its closed in switches its open position and vice versa.

The valve piston (24) also acts in the direction of the closed position of the valve (20) Spring element like coil spring (71).

The valve piston (24) can be moved with its valve disk (46) in a valve chamber (21) arranged. From the valve chamber (20) there is a connection (42) with one the compact control arrangement (10) controllable shut-off valve of the vacuum sewage system is connected to pressurize it to open it enable.

The vacuum required for this then flows through a connection (44) into the valve chamber (21) when the valve (20) is open, so its valve plate (46) one with the connection (44) opens connected opening (48).

From the connection (44) also leads a channel running in the housing jacket (50), which receives the valve piston (22) of the first valve (14) or exhaust valve tubular inner housing section (52) opens to open valve (14) to be connected to an inner chamber (56) via its valve chamber (54).

When the valve (14) is closed, the valve chamber (54) is connected via a check valve (58) closed to the valve chamber (54).

The tubular housing portion (52) coaxial with a portion of the spring (71) is surrounded, starts from a further intermediate floor (60), in which a Adjusting element (62) has an opening (64) which can be changed in cross-section and via which a connection between the chamber (56) and a control line (66) by a Housing opening (68) extends to a pressure equalization in the manner described below in the chamber (56).

The opening (68), which can be closed by a filter, not only connects to the Control channel (66), but also via the bore (26) in the housing base (28) Connection to the valve chamber (21) to compensate for pressure when the valve (20) is closed to the shut-off valve so that it can close.

Around the chamber (56) opposite a direct connection to the housing opening (68) to seal, proceeds from a cylindrical extension extending in the chamber (56) (70) of the valve piston (24) from a membrane (72) opposite the inner wall of the Housing (12) is sealed.

When a certain amount of waste water is reached in a pitot tube through the opening (18) on the membrane (16) transmit a dynamic pressure, the valve (14) opens so that the the negative pressure applied to the connection (44) via the channel (50) on the valve piston (22) can pass into the valve chamber (54) and the check valve opens, so that in the chamber (56) has a negative pressure (FIG. 2).

If the vacuum in the chamber (56) reaches a value which is sufficient to achieve the Force of the spring (71) supported on the intermediate floor (60) and on the other hand that of to overcome snap balls (30), (32) acting on the valve piston (24) opens in this way the control valve (20) abruptly and connects via the opening (48) to the Connection (42) to the shut-off valve, so that one to open the shut-off valve required negative pressure arrives. As a result, this can occur in the collection container accumulated waste water can be suctioned off (Fig. 3).

As soon as the wastewater is sucked off to the required extent, it breaks onto the membrane (16) acting dynamic pressure to an extent that the release valve (14) and thus also the check valve (58) are closed and thus no longer a negative pressure can pass into the chamber (56) via the channel (50) (FIG. 4). At the same time occurs in the Chamber (56) via the housing opening (68) and the control channel (66) and in cross section adjustable opening (64) a pressure equalization. Depending on the speed of the pressure compensation, which is predetermined by the cross section of the opening (64) the negative pressure causing the contraction of the spring (71) is reduced, so that the Spring force with further pressure equalization in the chamber (56) the adjustable forces of Snap balls (30), (32) can overcome. Thus, the control valve (20) suddenly in switch the closed position back (basic position according to FIG. 1). At this moment the negative pressure is interrupted via the connection (42) to the shut-off valve. About the Opening (68), the bore (26) surrounding the valve piston (24), the valve chamber (21) and the connection (42) then continues a pressure equalization to the shut-off valve, so that this can close again.

Due to the defined positions of the control valve (20) and the sudden changeover from its open to its closed position and vice versa, there can be no overlap occur with regard to the presence of the negative pressure.

The arrangement of the valves (14) and (20) within the cylindrical housing (12) and the course of the control channels (50), (66) within the housing wall and the Guide the valve pistons (22) and (24) in the intermediate floors (28) and (60) or by these outgoing tubular guides (52) ensures a compact structure.

Due to the adjustable speed of the vacuum reduction in the chamber (56) together with the spring (71) or the ball snappers (30), (32) becomes a mechanical one Highly functional timers provided, with defined opening times of the shut-off valve without overlaps.

Another essential feature is the limiter realized by the snap balls, which ensures that, on the one hand, an abrupt change in the state of the second valve occurs and on the other hand only then opening the valve and thus applying a vacuum the shut-off valve can take place if the negative pressure in the sewage system is sufficient, also really convey waste water through the shut-off valve.

An alternative embodiment corresponding to the structure and function of FIGS. 1 to 4 a control arrangement is shown in principle in FIG. 5. Basically Identical elements with the same reference numerals.

To also suddenly switch the second valve (20) from its open position enable its closed position, d. H. the initially existing connection between the vacuum connection (44) and the connection (42) to a not shown Shutting off the shut-off valve (illustration in FIG. 5) are not realized by means of snap balls Delimiter provided. Rather, a spontaneous switching of the second valve (20) realized by means of a magnet (74) and a plate (76) associated therewith.

5 is a magnet (74) in the housing section (28) Control arrangement arranged stationary, namely coaxially to the valve piston (78) of the second Valve (20). A metal plate (76) is provided opposite the magnet (74) connected to the membrane (72), which in turn is from the inner wall of the chamber (56) going out.

If - as in connection with the functional sequence of the control arrangement (10) of FIG. 1 to 4 has been explained - the chamber (56) is pressurized to the required extent, the valve (20), ie the valve head (23), can then move from the vacuum connection (44) leading opening (48) can be lifted off spontaneously when the in the chamber (56) prevailing negative pressure that acting on the metal plate (76) from the magnet (74) Power overcomes. At this moment the valve piston moves in the direction of the Arrow (80) to open the valve (20) so that there is a position that the Fig. 3 or Fig. 4 corresponds.

The holding force can be changed by the size of the metal plate (76) again the time of the sudden opening of the valve (20) depending on the prevailing negative pressure can be specified in the chamber (56).

In principle, the valve (20) is also closed abruptly when that Valve (14) closed and through the opening (68) and the line (66) and in 5 interchangeable throttle (64) effecting the time control Atmospheric pressure flows into the chamber (56). This creates a pressure, whereby the valve piston (78) due to the spring force caused by the membrane (72) in the is moved to its closed position to a certain extent, then when that of the Magnet (74) acting on the tarpaulin (76) is sufficient, the plate (76) to the Magnets (74) to pull, a sudden change of the valve to be described (20) to effect.

As described above, there is no spontaneous switchover from the beginning Valve (20) from its upper end position to its lower closed end position. Instead, the piston (78) is slowly moved in the opposite direction the arrow (80). To avoid that an undesirable during this lifting movement Overlap with the negative pressure led via the connection (42) to the shut-off valve and that via the opening (68) and the annular space (26), which coaxially the valve piston (78) surrounds, flowing atmospheric pressure takes place, the valve piston (78) has on the valve seat side a cylindrical extension (82) which, when the valve (20) is open, runs against a rotating one Seal (84) comes to rest against the opening (68) to the atmosphere Chamber (21) in the connection between the vacuum connection (44) and the shut-off valve connection (42) is to be blocked. The axial extent of the cylindrical Extension (82) with respect to the seal (84) chosen so that a seal only up to the time at which the plate (76) is gripped by the magnet (74) and by this is attracted.

As soon as the valve head (23) rests on the valve seat (48), there is a connection between the Connection (68) and the chamber (21) on the ring channel (26) given, since in this case the Valve piston (78) runs at a distance from the seal (84).

Claims (14)

1. A process for controlling a shut-off valve actuatable by reduced pressure, for a reduced pressure waste water system, wherein

   a first valve (14) is actuated by banking-up pressure caused by accumulated waste water,

   the pressure in a chamber (56) is adjusted by means of the first valve, in or adjacent which chamber there is displaceably arranged a valve piston (24), optionally acted on by a spring member (71, 72), of a second valve (20),

   reduced pressure reaches the shut-off valve via the second valve as a function of the pressure prevailing in the chamber, in order to open said shut-off valve, and

   the first valve closes when the banking-up pressure is absent and a pressure change necessary for closure of the second valve occurs in the chamber,

   characterised in that
   abruptly varying forces (30, 32, 38, 74, 76) act on the second valve (20) in such a way that, in the event of a given pressure change in the chamber (56) or in the region thereof, the second valve closes sharply, in order to shut off the shut-off valve with regard to the reduced pressure.
2. A process according to claim 1,
   characterised in that
   the chamber (56) or the region thereof is acted upon by reduced pressure to open the second valve (20), which reduced pressure is reduced adjustably when the banking-up pressure acting on the first valve (14) is absent.
3. A process according to claim 1 or claim 2,
   characterised in that
   in the event of a given pressure change in the chamber (56) or in the region thereof, the second valve (20) is switched over sharply (CLOSED/OPEN or OPEN/CLOSED) in such a way that reduced pressure either reaches the shut-off valve or is blocked off therefrom.
4. A process according to at least one of the preceding claims,
   characterised in that
   the second valve (20) is held in its position blocking off the reduced pressure from the shut-off valve by a force which is overcome in the presence of a banking-up pressure only when a reduced pressure necessary for sucking off waste water prevails.
5. A control arrangement (10) for a shut-off valve actuatable by reduced pressure, for a reduced pressure waste water system, comprising a first valve (14) actuatable by a banking-up pressure caused by accumulated waste water, a chamber (56) whose pressure may be adjusted via the first valve, in or adjacent which chamber there is displaceably arranged a valve piston (24), optionally acted on by a spring member (71, 72), of a second valve (20), via which reduced pressure reaches the shut-off valve as a function of the pressure prevailing in the chamber, in order to open said shut-off valve, the first valve closing and a pressure change necessary for closure of the second valve occurring in the chamber when the banking-up pressure is absent,
   characterised in that
   abruptly varying forces (30, 32, 38) act on the second valve (20), through at least one limiter (30, 32) or a retaining member (74, 76), in such a way that, in the event of a given pressure change in the chamber or in the region thereof, the second valve closes sharply the connection to the shut-off valve.
6. A control arrangement according to claim 5,
   characterised in that
   the at least one limiter (30, 32) or retaining member (74, 76) acts in such a way on the second valve (20) that opening of the second valve proceeds only in the event of reduced pressure allowing conveying of the waste water through the shut-off valve.
7. A control arrangement according to at least one of preceding claims 5-6,
   characterised in that
   the spring member (71) acting on the valve piston (24) of the second valve (20) is arranged in the pressure-adjustable chamber (56) or the region thereof.
8. A control arrangement according to at least one of preceding claims 5-7,
   characterised in that
   the valve piston (24, 70), displaceable inside the chamber (56), of the second valve (20) is held by a diaphragm (72), which is in turn sealed with respect to the region of the chamber in which the pressure change necessary for sharp switching over of the second valve occurs.
9. A control arrangement according to at least one of preceding claims 5-8,
   characterised in that
   the first and second valves (14, 20) are arranged in a preferably cylindrical housing (12) comprising connections (18,44) for the banking-up pressure and the reduced pressure and a connection (42) to the shut-off valve and in that the valve piston (24) of the second valve (20) is guided displaceably in a first housing portion (28), in that in the first housing portion (28) accommodating the valve piston (24) in axially displaceable manner there are arranged as limiters members (30, 32) acting radially on the valve piston and catching therein when the valve is closed or open or in that the diaphragm (72) connected with the valve piston (24) of the second valve (20) is held in a first position by means of a magnet (74) or may be moved, in the event of the given pressure change in the chamber (56) or the region thereof, sharply or extensively sharply from the first position into a second position or vice versa, wherein in the first position the second valve (20) blocks the reduced pressure connection to the shut-off valve and in the second position it opens the reduced pressure connection to the shut-off valve.
10. A control arrangement according to claim 9,
    characterised in that
    the members (30, 32) are spring-loaded balls, which catch in circumferential annular grooves (34, 36) in the valve piston (28) spaced relative to one another in accordance with the valve lift when the valve is respectively closed or open.
11. A control arrangement according to at least one of preceding claims 5-10,
    characterised in that
    a control line (50) leads from the reduced pressure connection (44) to a second housing portion (52) accommodating the valve piston (22) of the first valve (14) and closable by the valve disk thereof, wherein the control line (50) preferably takes the form at least in part as a channel extending within the housing walls.
12. A control arrangement according to at least one of preceding claims 5-11,
    characterised in that
    the valve disk of the first valve (14) is arranged displaceably in a valve chamber (54) closable with regard to the chamber (56) via a non-return valve (58).
13. A control arrangement according to at least one of preceding claims 5-12,
    characterised in that
    the pressure change in the chamber (56) or the region thereof setting a residual opening time of the second valve (20) when the banking-up pressure on the first valve (14) is absent proceeds by means of a cross-sectionally variable opening (64), which is connected with a housing opening (68) preferably closable by a filter.
14. A control arrangement according to claim 13,
    characterised in that
    the housing opening (68) is connected with the first housing portion (28) accommodating the valve piston (24) of the second valve (20) and is connected pressure-wise with the shut-off valve via the housing portion when the second valve is in the closed position blocking the reduced pressure with regard to the shut-off valve.

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