Pump system

Abstract

A pump (2) system includes a pump, a sensor (22; 28) arranged in or at a flow path (14), and a concentration measurement device measuring a concentration in liquid inside the flow path (14). The concentration measurement device includes the sensor (22; 28), as a concentration sensor, connected to an evaluation device (26) for evaluating readings of the sensor (22; 28). The evaluation device (26) is connected to a further signal source (20; 24), providing at least one further parameter, and is configured to carry out an evaluation of the reading of the sensor (22; 28), taking into account the further parameter provided by the further signal source (20, 24) to output the concentration in the liquid. A solar heating system includes the pump system.

Claims

1. A pump system comprising: a pump comprising a pump housing defining at least one flow path for a liquid, the at least one flow path being located inside the pump housing; a concentration measurement device measuring a concentration in the liquid inside the flow path, wherein the concentration measurement device comprises a sensor arranged in or at the flow path, and a further signal source providing at least one further parameter and an evaluation device configured to evaluate the sensor readings, wherein: the sensor is a concentration sensor configured to output sensor readings and is connected to the evaluation device; a portion of the concentration sensor is adjacent to a portion of the at least one flow path; the evaluation device is connected to the further signal source; the further signal source comprises a temperature sensor configured to detect the at least one further parameter, the at least one further parameter being a temperature of the liquid inside the flow path; and the evaluation device is configured to evaluate the sensor readings taking into account the at least one further parameter provided by the further signal source and to output a concentration in the liquid.

2. A pump system according to claim 1, wherein the temperature sensor is arranged in or at the flow path to detect the at least one further parameter of the liquid inside the flow path.

3. A pump system according to claim 2, wherein the sensor and the temperature sensor are arranged at a common position along the flow direction of the flow path with the sensor and the temperature sensor forming an integrated sensor.

4. A pump system according to claim 1, wherein the flow path is part of a flow path through the pump for the liquid pumped by the pump, wherein another portion of the concentration sensor is located in the flow path.

5. A pump system according to claim 1, wherein: the flow path is arranged inside the pump housing; another portion of the concentration sensor is configured to contact the liquid in the flow path; and the pump comprises an impeller in the pump housing.

6. A pump system according to claim 1, wherein the concentration sensor comprises an ultrasound sensor, an optical sensor or a capacitive sensor.

7. A pump system according to claim 1, wherein the sensor comprises an ultrasound sensor configured as a combined flow and concentration sensor.

8. A pump system according to claim 1, wherein the evaluation device is configured to carry out an evaluation of a reading of the sensor only when the at least one further parameter is below a predefined maximum limit value and/or is above a predefined minimum limit value.

9. A pump system according to claim 1, wherein: the pump comprises an electric drive motor with control electronics; and the evaluation device is signal connected to the control electronics.

10. A pump system according to claim 9, wherein: the control electronics forms the further signal source outputting the at least one further parameter.

11. A pump system according to claim 9, wherein the evaluation device is arranged inside an electronic housing containing control electronics of the pump and the evaluation device is integrated into the control electronics of the pump.

12. A pump system according to claim 1, wherein the at least one first sensor is arranged on an outlet side or on an inlet side of the pump.

13. A pump system according to claim 1, wherein the sensor is a concentration sensor configured to detect a glycol concentration.

14. A pump system according to claim 1, wherein the pump is a centrifugal pump configured as a circulator pump having a wet running electric drive motor.

15. A heating and/or cooling system comprising a pump system comprising: a pump comprising a pump housing defining at least one flow path for a liquid, the at least one flow path being located in an interior of the pump housing; a concentration measurement device measuring a concentration in the liquid inside the flow path, wherein the concentration measurement device comprises a sensor arranged in or at the flow path, and a further signal source providing at least one further parameter and an evaluation device configured to evaluate the sensor readings, wherein: the sensor is a concentration sensor configured to output sensor readings and is connected to the evaluation device; a portion of the concentration sensor is located adjacent to a portion of the at least one flow path; the evaluation device is connected to the further signal source; the further signal source comprises a temperature sensor configured to detect the at least one further parameter, the at least one further parameter being a temperature of the liquid inside the flow path; and the evaluation device is configured to evaluate the sensor readings taking into account the at least one further parameter provided by the further signal source and to output a concentration in the liquid.

16. A heating and/or cooling system according to claim 15, wherein: the temperature sensor is arranged in or at the flow path to detect the at least one further parameter of the liquid inside the flow path; and the concentration sensor comprises an ultrasound sensor, an optical sensor or a capacitive sensor.

17. A solar heating system comprising: at least one solar collector; and a pump system connected to the at least one solar collector, the pump system comprising: a pump with at least one flow path for a liquid; a concentration measurement device measuring a concentration in the liquid inside the flow path, wherein the concentration measurement device comprises a sensor arranged in or at the flow path, and a further signal source providing at least one further parameter and an evaluation device configured to evaluate the sensor readings, wherein: the sensor is a concentration sensor configured to output sensor readings and is connected to the evaluation device; the evaluation device is connected to the further signal source; and the evaluation device is configured to evaluate the sensor readings taking into account the further parameter provided by the further signal source and to output a concentration in the liquid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the drawings:

(2) FIG. 1a is a schematic cross sectional view of a pump device according to a first embodiment of the invention;

(3) FIG. 1b is a schematic cross sectional view of an alternative of the first embodiment according to FIG. 1a;

(4) FIG. 2a is a schematic cross sectional view of a pump system according to a second embodiment of the invention;

(5) FIG. 2b is a schematic cross sectional view of an alternative of the second embodiment according to FIG. 2a;

(6) FIG. 3a is a schematic cross sectional view of a pump system according to a third embodiment of the invention;

(7) FIG. 3b is a schematic cross sectional view of an alternative of the third embodiment according to FIG. 3a;

(8) FIG. 4 is a schematic view of an example for a pump system according to the invention in form of a solar heating system;

(9) FIG. 5 is a diagram in which the speed of sound in the fluid is shown in dependence on the temperature, for different concentrations.

DESCRIPTION OF PREFERRED EMBODIMENTS

(10) Referring to the drawings, the pump device as shown in FIG. 1a comprises a pump 2 having an inlet 4 and an outlet 6. The inlet 4 is connected to an inlet conduit 8 and the outlet 6 is connected to an outlet conduit 10. The inlet conduit 8 and the outlet conduit 10 may be part of a hydraulic system as for example a heating system, in particular a solar heating system as for example shown in FIG. 4. The inlet 4 and the outlet 6 are arranged in a pump housing 12 defining a flow path 14 from the inlet 4 to the outlet 6. In the pump housing 12 there is arranged an impeller 16 inside the flow path 14 for pumping the liquid, for example water or a water mixture through the flow path 14. The impeller 16 is driven by an electric motor 18 which is arranged in a motor housing connected to the pump housing 12. The electric drive motor 18 preferably is a wet-running motor, but may be any suitable drive motor. The drive motor comprises a motor control or control device 20 in form of control electronics controlling the electric drive motor of the pump. The control device 20 in particular may comprise a speed regulator. For speed regulation there may be a frequency converter as part of the control device 20.

(11) Into the pump system as shown in FIG. 1a there is integrated a system for concentration measurement inside the liquid pumped through the flow path 14, for example for detecting a glycol concentration in a water/glycol-mixture. This concentration measurement device comprises a first sensor 22 being a concentration sensor 22. Furthermore, there is arranged a temperature sensor 24 as a second sensor. The concentration sensor 22 and the temperature sensor 24 may be integrated into one sensor unit. In this embodiment the concentration sensor 22 and the temperature sensor 24 are arranged on the inlet side, i.e. upstream the impeller 16. However, it would also be possible that one of these two sensors or both are arranged on the outlet side, downstream the impeller 16, as for example shown in FIG. 3a. The concentration sensor 22 and temperature sensor 24 may be arranged inside the flow path 14 such that they are immersed into the fluid. However, preferably the sensors are configured for a contactless measurement so that the sensors 22 and 24 itself do not come into contact with the liquid inside the flow path 14, but measure the desired parameters from the outside. The concentration sensor 22 preferably is an ultrasonic sensor having an ultrasound source sending an ultrasound signal into the flow path 14 so that the signal is reflected on the opposite inner wall of the flow path. The reflected signal is detected by a detector integrated into the sensor 22. The concentration sensor 22 and the temperature sensor 24 are connected to an evaluation device 26 for evaluating the readings of the two sensors 22 and 24. The evaluation device 26 is outputting a concentration value and/or for example an alarm or switching signal dependent on the detected concentration. The evaluation device 26 is configured such that it can evaluate the reading from the concentration sensor 22 under consideration of the signal from the temperature sensor 24. For example, example, the evaluation of the concentration measurement is suspended or skipped if the detected temperature is too high or too low.

(12) Furthermore, in this embodiment the evaluation device 26 is connected to the control device 20. For other embodiments there may be an alternative or additional connection or communication to other devices, like for example a valve. Furthermore, connection may be established via a network, the internet, a cloud or a similar way of communication. This may be a bidirectional communication such that the evaluation device 26 can receive a signal from the control device 20, for example whether the drive motor 18 is running or not. Furthermore, it would be possible to output a speed signal from the control device 20 to the evaluation device 26. Also these signals can be considered by the evaluation device 26 when evaluating the reading from the concentration sensor 22. For example, the evaluation of the concentration reading from the concentration sensor 22 can be carried out only during certain operational conditions, for example during a certain speed of the drive motor 18 or if the drive motor 18 is switched off. Furthermore, it would be possible to have a communication in the opposite direction such that the evaluation device 26 sends control signals to the motor control 20, for example to bring the drive motor 18 into a desired operational condition for the concentration measurement, for example to set a certain rotational speed of the drive motor 18 or to switch off the drive motor 18 for a measurement. Furthermore, the evaluation device 16 may output a concentration value or a switching signal to the control device 20, for example to switch off the drive motor 18 if a predefined concentration value is exceeded. Additionally or alternatively the control device 20 may give an alarm signal to an operator if a certain concentration value is detected.

(13) FIG. 1b shows an alternative solution of the first embodiment in which the sensor 28 is an alternative to the concentration sensor 22 as described before. Differing from the design of the concentration sensor 22 the sensor 28 is configured having a transmitter 30 arranged on one side of the flow path and a receiver 32 arranged on the opposite side. The transmitter 30 sends out an ultrasound signal into the liquid in the flow path 14 and the receiver 32 detects the signal which has passed the flow path 14.

(14) The ultrasound sensors 22 and/or 28 may in addition also measure the flow inside the flow path 14 so that they form a combined flow/concentration sensor. Both, the evaluation of the flow and the concentration may be carried out by the evaluation device 26. For example, the flow reading of the sensor 22 or 28 may be input into the evaluation device 26 such that the detected flow can be regarded as a further parameter for the evaluation of the concentration.

(15) FIG. 2a shows a second embodiment similar to the first embodiment as shown in FIG. 1a. In the second embodiment the evaluation device 26 is integrated into the control device 20, i.e. the control electronics of the pump or drive motor 18. Furthermore, in this embodiment the control device 20 is arranged directly on the drive motor 18. The evaluation device 26 for example may be configured as a software module inside the control device or control electronics 20, respectively. However, it would also be possible to integrate a further electronics module forming the evaluation device 26 into the same housing as the control device 20. Also in the second embodiment the concentration sensor 22 and the temperature sensor 24 are connected to the evaluation device 26 which communicates with the further motor electronics of the control device 20 as described with reference to FIG. 1. Also for the second embodiment in an alternative solution as shown in FIG. 2b the alternative concentration sensor 28 as described with reference to FIG. 1b may be used. This means, also the concentration sensor 28 may be connected to an evaluation device 26 integrated into the control device 20.

(16) FIG. 3a shows a third embodiment according to the invention which is similar to the embodiment shown in FIG. 1a, however, the concentration measurement device is realized as a separate system which can be integrated into an existing pump system such to retrofit existing pumps or pump systems. Instead of the concentration sensor 22 as shown in FIG. 1a and the temperature sensor 24 as shown in FIG. 1a in this third embodiment a concentration sensor 22 and a temperature sensor 24 are arranged in an outlet conduit 10 connected to the outlet 6 of the pump housing 12. This may be a direct connection or a connection via a further pipe or pipe element. These two sensors are connected to the evaluation device 26 forming an external electronic device which may be connected for communication with the control device 20 of the drive motor 18. Via this communication according to a further preferred solution the evaluation device 26 may additionally receive a flow signal from a flow detecting module 34 as a further parameter for the evaluation of the concentration. The flow detection module 34 may detect the flow for example from electrical values of the drive motor 18 and may be realized as a software module.

(17) Also in this third embodiment, it would be possible to include the evaluation device 26 into the control device 20, for example as a software module in particular via a software update. Alternatively it would be possible to arrange the sensors 22 and 24 in the inlet conduit 8 instead of the outlet conduit 10 as shown.

(18) FIG. 3b shows an alternative of the third embodiment as shown in FIG. 3a. In the solution shown in FIG. 3b the sensors 22 and 28 are arranged in the inlet conduit 8. However, it would also be possible to alternatively arrange these sensors in the outlet conduit 10 as shown in FIG. 3a. Furthermore, in this alternative solution the alternative concentration sensor 28 is used. The concentration sensor 28 corresponds to concentration sensor 28 as described with reference to FIG. 1b and FIG. 2b. In the solution shown in FIG. 3b the evaluation device 26 is integrated into the control device 20 corresponding to the embodiment shown in FIG. 2a and FIG. 2b. However, it would also be possible to use the concentration sensor 28 with an external evaluation device 26 as shown in FIG. 3a.

(19) In all embodiments the ultrasonic sensors 22, 22, 28 and 28 may be combined flow/concentration sensors to measure both, flow and concentration in the liquid inside the flow path. The flow signal may be used as a further parameter by the evaluation device 26.

(20) FIG. 4 shows the use of a pump system as described before in a solar heating system. This system comprises a solar panel 36 connected to a hot water storage tank 38 via a closed hydraulic circuit 40. Inside this hydraulic circuit 40 there is circulating a liquid heat carrier, for example a water glycol mixture. For circulation there is provided a pump system as described with reference to FIGS. 1 to 3 having a pump 2 and a concentration measurement device having at least a concentration sensor 22, 22 and a temperature sensor 24, 24 connected to an evaluation device 26 communicating with the control device 20 of the pump 2. The arrangement of the sensors and the pump 2 as well as the evaluation device 26 may be as shown in FIGS. 1 to 3. The hot water tank 38 may have an inlet 42 for cold water and an outlet 44 for hot water. Furthermore, there are additional heating coils 46 connected to a boiler. In this arrangement the concentration measurement system as described before can detect the glycol concentration inside the liquid heat carrier and for example give an alarm if the concentration is below a predefined threshold. Furthermore, in such case for example the control device 20 may switch the pump 2 into a continuous operation mode to avoid freezing due to a concentration of glycol being below a required minimum.

(21) Signal courses for the signal speed within the flow path 14 are represented in FIG. 5 for four different concentrations conc0, conc1, conc2 and conc3. In FIG. 5, the speed u is plotted against temperature T. One can recognize that the speed differences between the individual concentrations decreases with an increasing temperature T. I.e. the measuring accuracy of the concentration decreases with an increasing temperature. A precise measurement is no longer possible from a temperature limit value T.sub.g. For this reason, according to the invention, one envisages the evaluation device 26 preferably skipping the evaluation of the measuring result of the concentration sensor 22, 22 on exceeding the temperature T.sub.g. The temperature may increase in certain operational conditions, and reduce again. The concentration measurement or evaluation of the reading of the concentration sensor 22, 22 is then for example only carried out by the evaluation device 26 for measurements at temperatures below the temperature limit value T.sub.g.

(22) While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

REFERENCE NUMERALS

(23) 2 pump 4 inlet 6 outlet 8 inlet conduit 10 outlet conduit 12 pump housing 14 flow path 16 impeller 18 electric motor 20 control device 22, 22 concentration sensor 24, 24 temperature sensor 26 evaluation device 28, 28 concentration sensor 30 transmitter 32 receiver 34 flow detecting module 36 solar panel 38 hot water storage tank 40 hydraulic circuit 42 inlet 44 outlet 46 heating coils T temperature T.sub.g temperature limit conc concentration u speed of sound