EP2072829B1 - Immersion pump - Google Patents

Description

The invention relates to a borehole pump according to the features specified in the preamble of claim 1.

With submersible pumps, it is nowadays state of the art to control these with a frequency converter, they thus generally have an engine electronics that make it necessary or at least expedient to detect essential operating variables of the pump and to take into account in the control and, if necessary . to process. These include, for example, the winding temperature of the motor, the temperature of the medium to be pumped, the delivery pressure, the ambient pressure and the like. To capture these variables, appropriate sensors are integrated into the submersible pumps. Out EP 1 324 011 A2 , US 3,021,788 and US 2,969,740 It belongs to the state of the art to incorporate one or more sensors into the flow path in the case of submersible pumps, in particular sewage pumps.

The arrangement of such sensors in submersible pumps is expensive because on the one hand must be a data connection to the control and Ragelelektronik the engine, on the other hand, an electrical supply is required and finally a reliable seal against the fluid must be guaranteed. However, prepares submersible pumps of the aforementioned type (dirty water pump), the sensor assembly constructively fewer problems, since the space of the pump verglelchswelse is large and the sensor can usually be incorporated at a suitable location within the pump housing, without that this essential structural changes of the pump unit itself are required. By contrast, this is different in borehole pumps, in which the space is particularly limited, especially in the radial direction and in which, if possible, a modular design should be given to provide different number of pump stages. In the case of borehole pumps, this therefore represents a spatial problem, which is why it has hitherto either dispensed with the installation of such sensors or had to calculate an enormous amount of construction work.

Against this background, the invention has the object, a generic borehole pump in such a way that one or more sensors can be arranged inexpensively at a suitable location and corresponding signal or data connected.

This object is achieved according to the invention by the features specified in claim 1. Advantageous embodiments of the invention will become apparent from the dependent claims, the following description and the drawings.

The borehole pump according to the invention has an electric drive motor and a single-stage or multi-stage centrifugal pump driven by it. According to the invention, one or more sensors of the pump are arranged in a sensor housing, which is liquid-flowed and liquid surrounds. The sensor housing is located between the motor and the pump, at the end of the pump or inside the pump. In this case, the sensor housing can either be arranged as a separate housing at the end of the pump or form part of the pump housing, so be formed integrally with this.

The basic idea of the present invention is, if possible, to accommodate the complete sensor system, but at least one or more sensors in a separate sensor housing, which at the end the pump, within the pump or between the motor and the pump, that is arranged at the other end of the pump. This sensor housing may have a modular design, so that it can optionally be retrofitted to existing pumps or at least pumps of the same series can be equipped with or without sensor housing, so can be shipped with and without sensors. Since the sensor housing is arranged between the motor and pump, within the pump or at the end of the pump, the borehole pump is thereby not changed in its outer contour, but only in their length, which is particularly important for borehole pumps. Since the sensor is typically connected to the flow of the pump on the one hand and the surrounding medium on the other hand, the sensor housing according to the invention is advantageously designed and arranged so that on the one hand flows through liquid and on the other hand surrounded by liquid. For example, temperatures and / or pressure can be detected by both the surrounding and the delivered fluid. As far as possible, the entire sensor system or at least a large part is arranged inside the sensor housing. if at all, only this sensor housing needs to be provided with an externally routed cable, which is an advantage in downhole pumps when the sensor housing is located at the top of the pump, where anyway only the power cable is adjacent to the delivery line. In the arrangement between the motor and pump, there is the advantage that the wiring can be done above the engine, which anyway requires a cable to the outside to the electrical power supply and possibly also to the control electronics.

Advantageously, the sensor housing is divided into a liquid-conducting housing part and a liquid-free housing part, which are separated by a preferably formed by stainless steel sheet housing wall. Such a housing wall may be formed in the manner of a split tube comparatively thin but absolutely liquid-tight be, so that, with the exception of the pressure and / or differential pressure sensors, if necessary, through the housing wall can be measured through, for example, temperature, vibration and the like. This has the considerable advantage that the highly moisture-sensitive electronics and sensors can be arranged in a reliable liquid-free housing part, whereas practically by the housing wall access to the pumped medium and / or the surrounding medium.

Appropriately, not only a partial flow but the entire flow of the pump is passed through the liquid-carrying housing part, wherein the housing part is formed so that it is quasi a further pump stage or a Rohverlängerung, that provides as little flow resistance. The sensors located in the sensor housing and possibly electronics requires comparatively little space, so that a small circumferential free space is usually sufficient to accommodate these components.

According to an advantageous development of the invention, it is provided to operate the electrical energy required to operate the sensors arranged in the sensor housing and, if necessary, to process the electrical signals emanating therefrom, to process them and convert them into digital data, to generate them directly inside the sensor housing, so as to be able to completely dispense with a line for powering the sensor housing. For this purpose, according to the invention, an induction arrangement is provided in the sensor housing, with which electrical energy is generated during operation of the pump.

Expediently, the induction arrangement has at least one magnet arranged rotatably in the liquid-conducting housing part and at least one induction coil arranged in the liquid-free housing part such that a current is induced in the coil by the magnet moving past the coil, which current can be used for the aforementioned purposes , Conveniently, two or more magnets are arranged, which cooperate with possibly a plurality of induction coils and thus form a kind of electrical generator.

In order to form a drive for the magnets is provided according to a development of the invention to store a pump impeller rotatably within the liquid-carrying housing part and to arrange so that it is rotated by the flow of the pump in rotation. In such a design, the sensor housing is formed quasi as a further passive pump stage, the flow passing through it drives the pump impeller arranged therein with the magnets attached thereto, thereby inducing a voltage in the one or more coils or generate a current and thus the sensor within the housing supply electricity.

According to one embodiment of the invention, such a passive pump impeller, which is arranged freely rotatable within the sensor housing, and on which at least one magnet is arranged, also form part of a flow meter, wherein then within the liquid-free housing part, an inductive pickup, such as a coil is arranged , so that the speed of the pump impeller can be detected and above the flow rate can be determined. It does not necessarily have a pump impeller rotatably arranged, it can be arranged rotatably a kind of wing, at the end of a magnet sits, which rotates faster or slower depending on the flow rate.

If, however, the sensor housing is more or less an integral part of the pump, so the pump can be structurally adapted thereto, then instead of a passive impeller advantageously the drive shaft can be extended into the sensor housing inside and there are provided with a holder which the or Magnets and is rotated by the drive shaft itself, also an active pump impeller may be provided which carries magnets.

In the case of integral design of the sensor housing in the pump housing, in principle, for example, in the case of a multi-stage borehole pump, any desired pump stage can be designed as a sensor housing by appropriate modification. So it is also conceivable, not just one, but to provide a plurality of sensor housing to monitor, for example, the pressure of each pump stage.

If, for example, it is possible to dispense with an electrical power supply of the sensor housing from the outside by means of the abovementioned design measures, then it is particularly expedient to carry out wirelessly also the electrical signals and / or sensor data to be taken out of the sensor housing. According to one embodiment of the invention, it is therefore provided to provide corresponding transmission means within the sensor housing to inductively couple the electrical signals de sensors or the data derived therefrom into an electrical cable routed outside on the sensor housing. Such a cable always runs parallel to the pump, especially in the case of borehole pumps. Such a cable for the electrical supply of the engine anyway required to use for data transmission is expedient, it is to transmit from the sensor housing out a corresponding signal on at least one conductor in the cable, which must be such that it by suitable filters of the Frequency of the power supply can be separated.

Alternatively, a radio transmission can be provided from the sensor housing, either to a receiver in the motor housing or to a typically arranged above the water surface E-lektronikgehäuse, which includes the control and regulating electronics for the engine.

Since the motor is anyway an electrical supply cable, this can be used by appropriate design in a simple manner for data transmission, either by modulating the signal or by providing a further conductor. It is then expedient to transmit the electrical signals of the sensors or the data derived therefrom from the sensor housing into the motor housing.

This can be transmitted by radio, but also mechanically by the pump housing, but preferably via the common shaft. For this purpose, in the region of the sensor housing, an electroacoustic transducer can be provided, which converts the electrical signal into a sound signal, typically an ultrasonic signal, and transmits it directly or indirectly to the shaft. On the motor side, an acoustoelectric transducer is then provided, which converts this signal back into an electrical signal, which is then led out in a suitable manner.

Within the sensor housing a variety of sensors may be arranged, typically one or more temperature sensors for detecting the temperature of the flow and / or the surrounding medium, a vibration sensor for detecting mechanical vibrations, a pressure or differential pressure sensor for detecting the ambient pressure and / or the delivery pressure. This list is only an example and can be supplemented by any other sensors.

At least these sensors are particularly advantageous, which need not necessarily be in communication with the surrounding or conveyed liquid, such. B. the pressure or differential pressure sensor, arranged in the liquid-free housing part. Thus, with suitable design of the housing wall of the temperature sensor can be separated by the housing wall of the liquid, as well as the vibration sensor, which brings obvious benefits.

Fig. 1

in stark vereinfachter schematischer Darstellung die Anordnung einer Bohrlochpumpe in einem Bohrloch,

Fig. 2

eine erste Ausführung eines Sensorgehäuses im Schnitt,

Fig. 3

eine zweite Ausführung eines Sensorgehäuses im Schnitt,

Fig. 4

eine dritte Ausführung eines Sensorgehäuses im Schnitt,

Fig. 5

den oberen Teil einer Bohrlochpumpe mit integriertem Sensorgehäuse im Schnitt,

Fig. 6

eine alternative Bauform mit im Pumpengehäuse integriertem Sensorgehäuse im Schnitt,

Fig. 7

eine erste Ausführung einer Bohrlochpumpe mit mechanischer Signalübertragung vom Sensorgehäuse zum Motorgehäuse in Schnittdarstellung und

Fig. 8

eine weitere Ausführung in Darstellung nach Fig. 7

The invention is explained in more detail with reference to embodiments shown in the drawing. Show it:

Fig. 1

in a highly simplified schematic representation of the arrangement of a borehole pump in a borehole,

Fig. 2

a first embodiment of a sensor housing in section,

Fig. 3

a second embodiment of a sensor housing in section,

Fig. 4

a third embodiment of a sensor housing in section,

Fig. 5

the upper part of a borehole pump with integrated sensor housing in section,

Fig. 6

an alternative design with integrated housing in the pump housing in section,

Fig. 7

a first embodiment of a borehole pump with mechanical signal transmission from the sensor housing to the motor housing in a sectional view and

Fig. 8

another embodiment in illustration after Fig. 7

The basis of Fig. 1 illustrated well pump 1 is lowered in a borehole 2. It consists of a lower engine part 3, of which in Fig. 1 only the motor housing is visible, this is followed up to a multi-stage centrifugal pump 4, the pump stages in Fig. 1 are indicated. Between engine 3 and pump 4 there are suction openings 5 through which the liquid located in the borehole 2 is sucked, conveyed upwards by the multistage centrifugal pump 4 and finally conveyed via a pressure line 6 to the point of consumption.

The motor 3 is supplied via a cable 7, which is guided long in the area of the centrifugal pump 4 on the outside and next to the pressure line 6 extends to a supply and control housing 8, via which the motor is supplied with power. Within the control housing 8 can For example, a frequency converter may be provided, as well as all means for controlling and monitoring the pump. Between the upper end of the centrifugal pump and the lower end of the pressure line 6, a sensor housing 9 is arranged, the structure of which is explained below by way of example.

This in Fig. 2 shown sensor housing 9a is constructed rotationally symmetrical, adapted in the outer periphery to the outer periphery of the pump stages and has on its underside a threaded connector 10 which is provided for incorporation into the end-side thread of the centrifugal pump 4. From the threaded connector 10, the housing wall projects radially outward, so that it is aligned with the circumferential housing wall of the underlying pump stages 4. Towards the upper end, the housing wall is retracted and provided on the inside with an internal thread 11 which corresponds in pitch and diameter to the internal thread at the upper end of the pump, so that the pressure line 6 either directly to the upper end of the pump or under inclusion of the sensor housing 9a can be connected.

The sensor housing 9a has a liquid-conducting inner housing part 12 and a liquid-free outer housing part 13, which are separated from one another by a gap-like wall 14. The liquid-carrying housing part 12 is substantially tubular and continues to expand the cross section of the pressure line 6, in order then again to pass into the threaded neck 10. In the extended area of the liquid-free housing part 13 is arranged, which forms a circumferential annular space in which sensors, namely a temperature sensor on the wall 14 adjacent to detecting the temperature of the fluid, a pressure sensor, the wall 14 penetrating to detect the pressure of the pumped liquid , a pressure sensor penetrates the outer wall for detection the ambient pressure and a vibration sensor are arranged. Furthermore, the electronics required for conditioning of the electrical signals emitted by the sensors are provided within this liquid-free housing part 13. The power supply of the sensors located within the sensor housing 9a via a cable 15, via which also the electrical signals of the sensors are led out. The cable 15 may be merged with the cable 7 or run parallel thereto.

That on the basis of Fig. 3 dargstellte sensor housing 9b has the same outer contour as the sensor housing 9a, but stored in the inner liquid-conducting part 12, a passive, ie non-driven pump impeller 16 which is driven by the flowing through liquid, ie rotated. On the underside of the pump impeller 16 magnets 17 are arranged, which run at a small distance to the wall 1. Immediately adjacent within the liquid-free housing part 13 adjacent to the wall 14 coils 18 are provided, in which when passing the magnets 16, a current is generated, which is used for the electrical power supply of the sensor housing 9b sensors and electronics. The sensor signals or the data determined therefrom are either inductively fed into the cable 7 guided there on the housing 9b via a data cable or else inductively.

In the case of Fig. 4 illustrated embodiment of the sensor housing 9c, instead of the pump impeller 16, a two-armed wing 19 is provided, which carries at its ends magnet 17, in the same manner as with reference to Fig. 3 previously described serve to generate electricity. The wings 19 are inclined with their end faces, so that they are also set in flow in rotation, but have a relation to the impeller 16 significantly lower flow resistance.

Based on Fig. 5-8 Embodiments are described in which the sensor housing is an integral part of the pump housing or is inextricably connected to the pump housing. In the execution according to Fig. 5 is the drive shaft for the wheels of the centrifugal pump 4 extended upward and carries at the top of a pump impeller 16, which is an active impeller due to the drive through the shaft 20. However, it is incorporated within a sensor housing 9d whose wall 14 separates the liquid-free housing part 13 from the rest of the pump housing. On the pump impeller 16 17 magnets are arranged at the bottom, in the same way as with reference to Fig. 3 previously described cooperate with corresponding coils 18 in the liquid-free housing part 13 and provide for the power supply within the sensor housing 9d. The sensor housing 9d can also be formed by modifying any pump stage. It can therefore be provided 9d also a plurality of sensor housing, if z. B. several pump stages to be monitored.

In the embodiment according to Fig. 6 the sensor housing 9e is also firmly connected to the last stage of the centrifugal pump 4, but there is the pump impeller 16 mounted within the sensor housing 9e freely rotatable, ie as a passive pump impeller similar to the arrangement according to Fig. 3 educated. Again, the power supply of the sensor via magnets 17 on the underside of the pump impeller 16, which cooperate with arranged within the liquid-free housing part 13 coils.

In the illustration according to Fig. 7 the upper end of a multi-stage centrifugal pump 4 is shown on the left, the lower end connects to the engine part 3, which is shown on the right. Through the housing part performs a common shaft 20, which continues in the engine part 3. The attached at the upper end of the pump 4 sensor housing 9f corresponds essentially based on Fig. 3 presented and explained. However, here is a signal transmission from the liquid-free housing part 13 out through the liquid through to the shaft 20 by mechanical waves. For this purpose, an electroacoustic transducer is provided within the liquid-free housing part 13 of the sensor housing 9f, which converts the sensor signals into ultrasonic signals, which are transmitted via the liquid to the shaft 20. At the motor end of the shaft 20, an acoustoelectric transducer 21 is provided, which converts these mechanical vibrations back into an electrical signal, which is then passed through the supply cable 7 of the motor to the supply and control housing 8.

In the case of Fig. 8 dargstellten embodiment, the shaft 20 is guided into the sensor housing 9g, on which a pump impeller 16 of the above-described embodiment according to Fig. 3 sitting. This pump impeller 16 is thus actively driven by the shaft 20. To transmit the ultrasonic vibrations it is sufficient here to vibrate the wall 14 or another housing part, which are transmitted to the shaft 20 due to the structure-borne sound propagation.

LIST OF REFERENCE NUMBERS

1 -

downhole pump

2 -

well

3 -

engine part

4 -

rotary pump

5 -

suction

6 -

pressure line

7 -

electric wire

8th -

Supply and control housing

9 -

Sensor housing in Fig. 1

9a -

Sensor housing in Fig. 2

9b -

Sensor housing in Fig. 3

9c -

Sensor housing in Fig. 4

9d -

Sensor housing in Fig. 5

9e -

Sensor housing in Fig. 6

9f -

Sensor housing in Fig. 7

9g -

Sensor housing in Fig. 8

10 -

threaded connector

11 -

inner thread

12 -

liquid-carrying housing part

13 -

liquid-free housing part

14 -

wall

15 -

electric wire

16 -

pump impeller

17 -

magnets

18 -

Do the washing up

19 -

wing

20 -

wave

21 -

acoustoelectric converter

Claims (12)

1. A bore-hole pump (1) with an electrical drive motor (3) and with a single-stage or multi-stage centrifugal pump (4) driven by this and having one or more sensors, characterised in that one or more sensors are arranged in a sensor housing (9) through which fluid flows, which is surrounded by fluid and which is arranged between the motor (3) and the pump (4), at the end of the pump (4) or within the pump (4).
2. A bore-hole pump (1) according to claim 1, characterised in that the sensor housing (9) comprises a fluid-leading housing part (12) and a fluid-free housing part (13), which are separated from one another by a housing wall (14) which is formed preferably from stainless steel sheet.
3. A bore-hole pump (1) according to one of the preceding claims, characterised in that the fluid-leading housing part (12) is subjected to the delivery flow of the pump (4).
4. A bore-hole pump (1) according to one of the preceding claims, characterised in that an induction arrangement (17, 18) is provided in the sensor housing (9), with which arrangement electrical energy is produced on operation of the pump (4).
5. A bore-hole pump (1) according to one of the preceding claims, characterised in that the induction arrangement (17, 18) comprises at least one magnet (17) rotatably arranged in the fluid-leading housing part (12), and that at least one induction coil (18) is arranged in the fluid-free housing part.
6. A bore-hole pump (1) according to one of the preceding claims, characterised in that the magnet or magnets (17) is/are arranged on a pump impeller (16) which is arranged in the fluid-leading housing part (12) and which is set into rotation by the delivery flow of the pump (4).
7. A bore-hole pump (1) according to one of the preceding claims, characterised in that a component rotatable by way of the delivery flow, in particular a pump impeller (16), is arranged in the fluid-leading housing part (12) and is provided with at least one magnet (17) which cooperates with an inductive sensor arranged within the fluid-free housing part (12), and forms part of a flowmeter.
8. A bore-hole pump (1) according to one of the preceding claims, characterised in that the magnet or magnets (17) are seated on a pump impeller (16) which is rotatably arranged in the fluid-leading housing part (12) and which is arranged in a rotationally fixed manner on the drive shaft (20) of the pump (4), said drive shaft being extended up to into the fluid-leading housing part (12).
9. A bore-hole pump (1) according to one of the preceding claims, characterised in that means are provided within the sensor housing, in order to inductively couple the electrical signals of the sensors or data derived therefrom, into an electrical cable (7) led at the outside on the sensor housing (9).
10. A bore-hole pump (1) according to one of the preceding claims, characterised in that means (20, 21) for the signal transmission and/or data transmission from the sensor housing (9) to the motor housing are provided.
11. A bore-hole pump (1) according to one of the preceding claims, characterised in that an electro-acoustic transducer acting upon the shaft (20) is provided on the sensor housing side and an acousto-electrical transducer (21) is provided on the motor side, and the signal transmission and/or data transmission is effected mechanically by the shaft (20).
12. A bore-hole pump (1) according to one of the preceding claims, characterised in that the sensor housing (9) comprises a temperature sensor, a vibration sensor, a flow sensor and/or a pressure sensor or differential pressure sensor.

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