Method for controlling several pumps

• US 7,195,462 B2
• Filed: 08/22/2003
• Issued: 03/27/2007
• Est. Priority Date: 08/23/2002
• Status: Active Grant

• Current Assignee: Grundfos A/S (Poul Due Jensens Fond)
• Original Assignee: Grundfos A/S (Poul Due Jensens Fond)
• Inventors: Nybo, Peter Jungklas, Ilves, Lasse, Yli-Korpela, Heikki
• Primary Examiner(s): Stashick; Anthony D.
• Assistant Examiner(s): Belt; Samuel E.
• Application Number:
  US10/646,241
• Publication Number:
  US 20040071554A1
• Time in Patent Office: 1,313 Days
• Field of Search: 417/3, 417/4, 417/53, 417/36, 417/38, 417/426
• US Class Current: 417/53
• CPC Class Codes: F04D 15/029 for pumps operating in parallel

Abstract

The invention relates to a method for controlling several pumps in a pump sump, with which each pump comprises a switch which switches on the pump and each pump after its running is first blocked and depending on the running of the further pumps in the pump sump is released again. The invention further relates to a pump for carrying out this method.

Claims

1. A method for controlling one or more pumps in a pump sump with which each pump comprises a signal generator which switches on the pump, and each pump subsequent to its running is firstly automatically blocked by changing its switching value at which the pump is switched on by the signal generator from an initial switching value to a second switching value so that the same pump is prevented from being directly activated when again reaching said initial switching value, and depending on the running of the further pumps in the pump sump is released again.

2. A method according to claim 1, wherein each pump comprises means for detecting a number of pumps applied in operation in the pump sump.

3. A method according to claim 2, wherein each pump by way of a sensor detects the running of a further pump and with this detects said number of applied pumps.

4. A method according to claim 1, wherein in each pump there is provided a level sensor.

5. The method as recited in claim 4, wherein said level sensor is a pressure sensor.

6. A method for controlling one or more pumps in a pump sump with which each pump comprises a signal generator which switches on the pump, and each pump subsequent to its running is firstly automatically blocked by changing its switching value at which the pump is switched on by the signal generator so that the same pump is prevented from being directly activated when again reaching said initial switching value, and depending on the running of the further pumps in the pump sump is released again, wherein for each pump subsequent to its operation a fluid level threshold value at which the pump is started is firstly increased proceeding from an initial threshold value and depending on the running of the further pumps in the pump sump is reduced again.

7. A method for controlling one or more pumps in a pump sump with which each pump comprises a signal generator which switches on the pump, and each pump subsequent to its running is firstly automatically blocked by changing its switching value at which the pump is switched on by the signal generator so that the same pump is prevented from being directly activated when again reaching the initial switching value, and depending on the running of the further pumps in the pump sump is released again, wherein a fluid level threshold value for each pump is reduced in steps by a predefined value after the running of a further pump.

8. A method according to claim 7, wherein the reduction of said fluid level threshold value is effected according to a geometric sequence.

9. A method according to claim 7, wherein said fluid level threshold value after the operation of a further pump is in each case reduced to a level which is dependent on the number of the previously run pumps.

10. A method for controlling one or more pumps in a pump sump with which each pump comprises a signal generator which switches on the pump, and each pump subsequent to its running is firstly automatically blocked by changing its switching value at which the pump is switched on by the signal generator so that the same pump is prevented from being directly activated when again reaching the initial switching value, and depending on the running of the further pumps in the pump sump is released again, wherein a fluid level threshold value for each pump is reduced in steps by a predefined value after the running of a further pump, wherein said fluid level threshold value after the operation of a further pump is in each case reduced to a level which is dependent on the number of the previously run pumps;

wherein said fluid level threshold value in each case is reduced to a level which corresponds to

$x+\mathrm{\Delta <br><br>}<br><br><br><br>x·<br><br>\frac{1}{n}$

wherein x corresponds to the initial threshold value, Δ

x the amount by which said fluid level threshold value has been increased with respect to the initial threshold value, and n the number of previously run pumps.

11. A method for controlling one or more pumps in a pump sump with which each pump comprises a signal generator which switches on the pump, and each pump subsequent to its running is firstly automatically blocked by changing its switching value at which the pump is switched on by the signal generator so that the same pump is prevented from being directly activated when again reaching said initial switching value, and depending on the running of the further pumps in the pump sump is released again, wherein each pump after its

12. A method for controlling one or more pumps in a pump sump with which each pump comprises a signal generator which switches on the pump, and each pump subsequent to its running is firstly automatically blocked by changing its switching value at which the pump is switched on by the signal generator so that the same pump is prevented from being directly activated when again reaching said initial switching value, and depending on the running of the further pumps in the pump sump is released again, wherein the pump automatically detects a condition in which no further pumps are arranged in the pump sump, and automatically lifts their blocking.

13. A pump comprising a signal generator and control means for activating the pump, wherein the control means comprises a detector for detecting the operation of at least one other pump in the same pump sump, a blocking function which blocks the pump by changing its switching value from an initial switching value to a second switching value at which the pump is switched on so that the same pump is prevented from being directly activated when again reaching the initial switching value, and a release function which releases the pump again depending on the operation of further pumps in the sump pump.

14. A pump according to claim 13, wherein the control means comprises means for detecting the number of pumps in a pump sump.

15. A pump according to claim 13, wherein said pump comprises a level switch.

16. A pump according to claim 15, wherein said blocking function increases a threshold value of said level switch and the release function reduces said threshold value of said level switch.

17. A pump according to claim 16, wherein the control means is designed in a manner such that the threshold value in each case after detecting the running of a further pump is reduced in steps by a predefined value.

18. A pump according to claim 15, wherein the means for detecting the operation of the further pumps in said pump sump accesses signals of the level switch.

19. The pump as recited in claim 15, wherein said level switch is a pressure sensor.

20. A pump according to claim 13, wherein the control means is integrated into said pump.

21. A pump with a signal generator and a control for activating a pump with an initial switching value, wherein said control comprises a detector for detecting the operation of at least one pump in the same pump sump, a blocking function which blocks the pump by changing its switching value from said initial switching value to a second value and a release function which changes said second switching value to release the pump in response to the operation of further pumps.

22. The pump according to claim 21, wherein said control comprises a detector for detecting a number of pumps in a pump sump.

23. The pump according to claim 21, wherein said pump comprises a level switch comprising a pressure sensor.

24. The pump according to claim 23 wherein said detector for detecting the operation of the further pumps in a pump sump is responsive to signals of the level switch.

25. A pump with a signal generator and a control for activating a pump with an initial switching value, wherein said control comprises a detector for detecting the operation of at least one pump in the same pump sump, a blocking function which blocks the pump by changing its switching value from said initial switching value to a second value and a release function which changes said second switching value to release the pump in response to the operation of further pumps;

wherein said pump comprises a level switch comprising a pressure sensor; and

wherein said blocking function increases a threshold value of said level switch and the release function reduces the threshold value of said level switch.

26. A pump with a signal generator and a control for activating a pump with an initial switching value, wherein said control comprises a detector for detecting the operation of at least one pump in the same pump sump, a blocking function which blocks the pump by changing its switching value from said initial switching value to a second value and a release function which changes said second switching value to release the pump in response to the operation of further pumps;

wherein said pump comprises a level switch comprising a pressure sensor;

wherein said blocking function increases a threshold value of said level switch and the release function reduces the threshold value of said level switch; and

wherein said control is designed in a manner such that said threshold value in each case after detecting the running of a further pump is reduced in steps by a predetermined value.

27. A pump with a signal generator and a control for activating a pump with an initial switching value, wherein said control comprises a detector for detecting the operation of at least one pump in the same pump sump, a blocking function which blocks the pump by changing its switching value from said initial switching value to a second value and a release function which changes said second switching value to release the pump in response to the operation of further pumps;

wherein said control is integrated into the pump.