Drain safety and pump control device

• US 20080003114A1
• Filed: 11/17/2006
• Published: 01/03/2008
• Est. Priority Date: 06/29/2006
• Status: Active Grant

• Current Assignee: Hayward Industries, Inc.
• Original Assignee: Hayward Industries, Inc.
• Inventors: Levin, Alan R., Ortiz, Gary
• Granted Patent: US 7,931,447 B2
• Time in Patent Office: Days
• US Class Current: 417/306
• CPC Class Codes: F04B 49/002 Hydraulic systems to change the pump delivery
• CPC Class Codes: F04B 49/065 and making use of computers

Abstract

A drain protection device and pump controller for pools, spas, fountains and other fluid containment and circulation systems has a vacuum sensor for sensing a level of vacuum present in the suction conduit leading to the pump(s). The vacuum level is monitored by a computer that controls a vent valve that can vent to atmosphere to reduce the vacuum exerted at a drain. In applications with a flooded pump, e.g., above-ground pools, the vent valve may control the discharge of an accumulator that injects fluid pressurized by the return line into the suction conduit to reduce the vacuum therein. The computer also controls the pump(s) present in the circulation system, viz., turns them off to relieve vacuum when a drain is occluded and also runs them at the selected speed based upon a schedule. The vacuum criteria for vacuum reduction may include progressively sensitive values, some of which may be empirically based. Vacuum criteria may be maintained based upon the operational state of the circulation system, e.g., priming, stabilized running or cleaning. Low vacuum limits protect the pump(s) from dry running. A clogged vacuum conduit leading to the vacuum sensor is sensed based upon the presence of vacuum levels that are atypically constant and error processing invoked.

Claims

1. A controller system for a fluid containment and circulation system having a fluid receptacle with a fluid outlet through which fluid exits the receptacle, a fluid inlet for returning fluid to the receptacle, a pump that moves the fluid from the fluid outlet to the fluid inlet, a suction conduit providing fluid communication between the fluid outlet and the pump and a return conduit providing fluid communication between the pump and the fluid inlet, comprising:

(A) a vacuum sensor for sensing a level of vacuum present in the suction conduit and producing a corresponding output;

(B) a vent valve having at least two positions, a first position which fluidly connects the suction conduit to matter outside the suction conduit and a second position which isolates the suction conduit from matter outside the suction conduit;

(C) a computer for receiving the output of said vacuum sensor, said computer programmed with a program that compares the vacuum sensor output to at least one predetermined vacuum criteria and selectively generates control outputs to said vent valve to determine the position of said vent valve and to the pump to control the operation of the pump, based upon said vacuum sensor output.

2. The system of claim 1, further including an accumulator for storing fluid pressure present in the return conduit, said accumulator having an outlet fluidly connected to said vent valve, such that when said vent valve is placed in said first position, the fluid pressure stored in said accumulator is at least partially discharged through said vent valve into said suction conduit.

3. The system of claim 2, further including a pressurized fluid conduit extending between said return conduit and said accumulator and a check valve disposed there between, said check valve permitting fluid to flow into said accumulator from said return line through said pressurized fluid conduit, but preventing flow in the opposite direction.

4. The system of claim 3, further including an accumulator outlet conduit extending between said accumulator and said vent valve, said accumulator outlet conduit passing fluid ejected by said accumulator when said vent valve is placed in said first position.

5. The system of claim 4, wherein said vent valve fluidly connects the suction conduit and said vacuum sensor in said second position.

6. The system of claim 4, wherein said accumulator has a substantially cylindrical body closed at first and second ends thereof, at least one of said first and second ends being closed by a removable closure, a piston received within a bore in said cylindrical body, a resilient member captured between the piston and said closure and urging said piston away from said closure, said cylindrical body having an opening through which pressurized fluid may enter into said bore, the pressurized fluid displacing said piston against said spring towards said closure, said spring pushing said piston away from said closure and ejecting the fluid out of said accumulator through said opening when said vent valve is placed in said first position.

7. The system of claim 5, wherein said vent valve is an electronic solenoid valve.

8. The system of claim 1, wherein said computer selectively operates the pump on a time schedule that is specified by an operator of said system.

9. The system of claim 8, wherein the pump is a two speed pump, said computer selectively operating the pump at a first speed and a second speed on a time schedule that is specified by the operator of the system.

10. The system of claim 9, further comprising an override switch to control the pump at a selected speed independently of said time schedule.

11. The system of claim 10, wherein said override switch is a logical switch, an ON/OFF state of which is an input to said computer.

12. The system of claim 8, wherein the fluid containment and circulation system includes a booster pump for powering a cleaner, said computer selectively operating the booster pump on a time schedule that is specified by the operator of the system.

13. The system of claim 12, further comprising a logical override switch to control said booster pump, an ON/OFF state of said override switch being an input to said computer.

14. The system of claim 1, wherein the matter outside the suction conduit is the atmosphere.

15. The system of claim 14, wherein said vent valve fluidly connects the suction conduit and said vacuum sensor in said second position.

16. The system of claim 15, further comprising a filter formed from air-permeable media positioned between said vent valve and the atmosphere for filtering air that passes through said vent valve when in said first position.

17. The system of claim 14, further comprising an emergency vacuum release switch, said vacuum release switch being a logical switch in normally closed position and having outputs to said computer and triggering the computer to position said vent valve in said first position and turn the pump OFF.

18. A method for controlling a fluid containment and circulation system having a fluid receptacle with a fluid outlet through which fluid exits the receptacle, a fluid inlet for returning fluid to the receptacle, a pump that moves the fluid from the fluid outlet to the fluid inlet, a suction conduit providing fluid communication between the fluid outlet and the pump and a return conduit providing fluid communication between the pump and the fluid inlet, a vacuum sensor for sensing a level of vacuum present in the suction conduit and producing a corresponding output, a vent valve having at least two positions, a first position which fluidly connects the suction conduit to matter outside the suction conduit and a second position which isolates the suction conduit from matter outside the suction conduit and a programmed computer, comprising the steps of:

(A) storing at least one vacuum criteria in said computer;

(B) receiving the output of said vacuum sensor in said computer;

(C) comparing the vacuum sensor output to the at least one vacuum criteria; and

(D) selectively generating control outputs to said vent valve as determined by the computer to determine the position of said vent valve and to control the operation of the pump, based upon said vacuum sensor output.

19. The method of claim 18, wherein the at least one vacuum criteria includes a high vacuum limit and further comprising the steps of

(E) positioning the vent valve to the first position when the result of comparing the vacuum sensor output to the high vacuum limit indicates that the high vacuum limit has been violated;

and

(F) turning the pump OFF when the high vacuum limit has been violated.

20. The method of claim 19, wherein the at least one vacuum criteria includes a low vacuum limit and further comprising the step of turning the pump OFF when the low vacuum limit has been violated.

21. The method of claim 20, wherein said at least one vacuum criteria includes a vacuum range between a relative high limit and a relative low limit, and further comprising the step of calculating the vacuum range relative to an empirically measured vacuum level.

22. The method of claim 21, wherein at least one of said high vacuum limit, said low vacuum limit and said vacuum range have a plurality of values, a first corresponding to a first mode of operation of the fluid containment and circulation system and a second corresponding to a second mode of operation.

23. The method of claim 21, wherein the modes of operation of the fluid containment and circulation system include pump priming mode, stabilized mode, and cleaning mode.

24. The method of claim 23, wherein the plurality of values are calculated relative to empirical vacuum levels measured during the operation of the fluid containment and circulation system in the plurality of operational modes.

25. The method of claim 19, if said steps (C) and (D) result in positioning the vent valve in the first position and turning the pump OFF, further comprising the steps of

(F) waiting a predetermined period;

(G) positioning the vent valve to the second position; and

(H) restarting the pump.

26. The method of claim 25, further comprising the steps of repeating steps (F) through (H) a predetermined number of times.

27. The method of claim 26, further comprising the steps of shutting the pump OFF for an indeterminate period following said step of repeating the predetermined number of times and requiring overt operator input to restart the pump.

28. The method of claim 18, further comprising the step of saving a log of violations of the vacuum criteria in computer readable media.

29. The method of claim 28, further comprising the step of saving a record of operational states and operator inputs in the log.

30. The method of claim 18, wherein said at least one predetermined vacuum criteria includes a rate of change of the vacuum level.

31. The method of claim 18, wherein the fluid containment and circulation system includes an emergency stop switch and further including the steps of monitoring the state of the emergency stop switch and, in the event that the emergency stop switch is pressed, placing the vent valve in the first position and shutting the pump OFF.

32. The method of claim 31, further including the step of activating a sensory alarm when the emergency stop switch is pressed.

33. The method of claim 18, further including the steps of periodically varying at least one of the vent valve position and the operational state of the pump and monitoring the vacuum level to test the operability of the vacuum sensor and the vent valve.

34. The method of claim 18, further comprising the steps of receiving and storing an operator-determined pump schedule in computer readable media, periodically checking the time and comparing it to the pump schedule to determine the operator defined operational state of the pump for that time and controlling the operational state of the pump accordingly.

35. The method of claim 34, wherein the pump is a two-speed pump and wherein the operational state of the pump includes the speed at which the pump runs.

36. The method of claim 34, wherein the fluid containment and circulation system includes a booster pump and wherein the operational state of the booster pump is determined by the operator-determined pump schedule.

37. The method of claim 34, wherein the fluid containment and circulation system includes an override switch by which the operator can control the operational state of the pump independently of the operational state indicated by the operator-determined pump schedule.

38. The method of claim 18, wherein the fluid level in the fluid receptacle is at a higher elevation than the pump, and further comprising the step of injecting a pressurized fluid through the vent valve when the valve is in the first position.

39. The method of claim 38, wherein the fluid containment and circulation system includes an accumulator for storing fluid under pressure and wherein said step of injecting includes discharging the fluid stored under pressure in the accumulator.

40. The method of claim 39 wherein the fluid containment and circulation system has a fluid connection between the return conduit and the accumulator with a check valve therein and further comprising the steps of passing fluid pressurized by pressure in the return conduit through the check valve into the accumulator and preventing reverse flow through the check valve.

41. The method of claim 18, further including a step of cycling the vent valve from the second position to the first position and back to the second position at least once when the pump is started.

42. The method of claim 41, wherein said step of cycling includes a plurality of transitions between the second and first positions of the vent valve.

43. The method of claim 21, wherein the relative high limit is lower than the high limit and the relative low limit is greater than the low limit.

44. The method of claim 18, wherein the at least one vacuum criteria includes the constancy of the vacuum level and further comprising the steps of positioning the vent valve to the first position when the result of comparing a plurality of vacuum readings taken at different times indicates that the vacuum is constant in an operating mode typified by a varying vacuum level.

45. The method of claim 44, further comprising the step of turning the pump OFF.

46. The method of claim 44, further comprising the step of repositioning the vent valve to the second position and subsequently checking the vacuum level to ascertain that it fluctuates in a normal manner, otherwise terminating pump operation and placing the vent valve in the first position.