Air filtration system control

• US 7,351,274 B2
• Filed: 08/17/2005
• Issued: 04/01/2008
• Est. Priority Date: 08/17/2005
• Status: Active Grant

• Current Assignee: Trane International Inc. (Trane Technologies plc)
• Original Assignee: American Standard Companies Incorporated (Ideal Standard International Topco SCA)
• Inventors: Helt, Robert W., Boydstun, Roger L., Vendt, Stephen J., Hagan, J. Mark
• Primary Examiner(s): Chiesa; Richard L.
• Application Number:
  US11/205,733
• Publication Number:
  US 20070039462A1
• Time in Patent Office: 958 Days
• Field of Search: 96/15, 96 18- 31, 96 39- 41, 96/51, 95 2- 7, 95/25, 95/57
• US Class Current: 95/2
• CPC Class Codes: B03C 2201/10 Ionising electrode has multiple serrated ends or parts
• CPC Class Codes: B03C 3/09 characterised by presence of stationary flat electrodes arranged with their flat surfaces at right angles to the gas stream
• CPC Class Codes: B03C 3/12 characterised by separation of ionising and collecting stations
• CPC Class Codes: B03C 3/155 Filtration
• CPC Class Codes: B03C 3/47 flat, e.g. plates, discs, gratings
• CPC Class Codes: B03C 3/68 Control systems therefor electricity supply or control systems for cleaning the electrodes B03C3/746, B03C3/763

Abstract

An intense field dielectric air filtration system associated with an air conditioning unit includes a microprocessor based control system which may be connected to the thermostat of the air conditioning unit to energize the air filtration system in response to a call for heat or cooling signal at the thermostat or startup of the fan motor for the air conditioning unit. The control system includes a power supply for the air filtration system together with voltage and current monitoring circuits for detecting a fault condition. Filtration system on/off and timing function reset switches are connected to the microprocessor and visual displays, including a multicolored LED bargraph display, are controlled by the microprocessor to indicate voltage potential applied to the air filtration system, a fault condition or a test mode.

Claims

1. In an air filtration system for an air conditioning unit, said filtration system including at least one filter unit mounted on support structure and including an array of passages through which an air flowstream may pass relatively free and through a high voltage electric field for collecting particles on said filter unit from said air flowstream, and an electric field charging unit mounted on said support structure upstream from said filter unit with respect to the direction of airflow through said filtration system, a control system for said filtration system including:

a high voltage power supply adapted to be operably connected to said field charging unit and said filter unit;

a source of electric power;

a signal input circuit adapted to be connected to a controller associated with said air conditioning unit; and

a microprocessor operably connected to said power supply and said signal input circuit for controlling application of a high voltage potential to at least one of said field charging unit and said filter unit.

2. The combination set forth in claim 1 wherein:

said control system includes a high voltage monitoring circuit connected to said power supply and said microprocessor for monitoring output voltage from said power supply to said at least one of said field charging unit and said filter unit.

3. The combination set forth in claim 1 including:

a voltage monitoring circuit operably connected to said microprocessor and to conductors connected to said source of electric power for monitoring the input voltage to said power supply.

4. The combination set forth in claim 1 including:

a circuit for monitoring currently input to said power supply operably connected to said microprocessor.

5. The combination set forth in claim 1 wherein:

said control system includes a circuit for monitoring a signal from said controller indicating at least one of energization of said air conditioning unit and a fan motor for said air conditioning unit and said microprocessor is operable to control said power supply to provide high voltage potential to said at least one of said field charging unit and said filter unit in response to said signal from said controller.

6. The combination set forth in claim 5 wherein:

said controller comprises a thermostat for said air conditioning unit.

7. The combination set forth in claim 1 wherein:

said control system includes a circuit including an interlock switch interposed said source of power and said power supply and responsive movement of an access door for said filtration system.

8. The combination set forth in claim 1 including:

a power control switch operably connected to said microprocessor for enabling said control system to energize said power supply to supply high voltage potential to said at least one of said field charging unit and said filter unit.

9. The combination set forth in claim 1 including:

a visual display operably connected to said microprocessor for providing visual signals indicating at least one of filter life before requiring servicing of said filter unit, voltage potential output from said power supply and a fault condition of one of said control system and said filtration system.

10. The combination set forth in claim 9 wherein:

said visual display includes multicolored indicators for indicating voltage potential imposed on said at least one of said filter unit and said field charging unit.

11. The combination set forth in claim 1 including:

a switch connected to said microprocessor for resetting a timing function associated with providing a visual display signal indicating requiring servicing of at least one of said filter unit and a prefilter unit associated with said filtration system.

12. In an air filtration system for an air conditioning unit, said filtration system including at least one filter unit mounted on support structure and including an array of passages through which an air flowstream may pass relatively free and through a high voltage electric field for collecting particles on said filter unit from said air flowstream, an electric field charging unit mounted on said support structure upstream from said filter unit with respect to the direction of airflow through said filtration system and a control system for said filtration system including a power supply adapted to be operably connected to said field charging unit and said filter unit, a signal input circuit connected to a controller associated with said air conditioning unit, and a microprocessor operably connected to said power supply and said signal input circuit for controlling application of a high voltage potential to at least one of said field charging unit and said filter unit, the method including the step of:

causing said microprocessor to operate said power supply to supply high voltage potential to at least one of said field charging unit and said filter unit responsive to a signal from said controller.

13. The method set forth in claim 12 including the step of:

causing said microprocessor to operate said power supply after a predetermined time period dependent on a signal received from said controller indicating one of startup of one of a heating and cooling operation of said air conditioning unit and startup of a fan motor for said air conditioning unit, respectively.

14. The method set forth in claim 12 including the step of:

causing said power supply to supply a voltage potential to said one of said field charging unit and said filter unit at progressively higher voltages over a predetermined period of time.

15. The method set forth in claim 12 including the step of:

causing said microprocessor to implement a delay for a predetermined of time of supplying a voltage from said power supply to said one of said field charging unit and said filter unit in response to replacement of at least one of said field charging unit and said filter unit.

16. The method set forth in claim 12 including:

causing said microprocessor to shut off said power supply in response to absence of a signal from said controller.

17. The method set forth in claim 12 including the step of:

causing an interlock switch to shut off power to said power supply in response to opening a door associated with said filtration system, which door provides access to at least one of said field charging unit and said filter unit.

18. The method set forth in claim 12 including the step of:

causing said microprocessor to shut off operation of said power supply to supply voltage to said one of said field charging unit and said filter unit in response to predetermined maximum current sensed by a power supply input current monitor circuit associated with said control system.

19. The method set forth in claim 12 including the step of:

causing said microprocessor to shut off power output from said power supply in response to a high voltage monitoring circuit of said control system detecting a change in output voltage of said power supply of a predetermined amount.

20. The method set forth in claim 12 including the step of:

causing said microprocessor to shut off output from said power supply in response to actuation of a control system power on and off switch for more than a predetermined period of time.

21. The method set forth in claim 12 including the step of:

causing a visual display connected to said control system to provide multicolored visual signals indicating when the voltage supplied to said one of said field charging unit and said filter unit is reduced to a predetermined level.

22. The method set forth in claim 21 including the step of:

causing said microprocessor to indicate at said display at least one of a fault mode and a predetermined test mode of said control system.

23. The method set forth in claim 22 including the step of:

displaying one or more selected fault conditions by said visual display.

24. The method set forth in claim 12 including the step of:

operating a reset switch for a predetermined period of time for resetting a timing function in said microprocessor for indicating when servicing is required of one of a prefilter unit and said filter unit.

25. In an air filtration system for an air conditioning unit, said filtration system including at least one filter unit mounted on support structure and including an array of passages through which an air flowstream may pass relatively free and through a high voltage electric field for collecting particles on said filter unit from said air flowstream, and an electric field charging unit mounted on said support structure upstream from said filter unit with respect to the direction of airflow through said filtration system, a control system for said filtration system including:

a low voltage source of electric power;

a high voltage power supply operable to be connected to said low voltage source and at least one of said field charging unit and said filter unit;

a signal input circuit connected to a controller associated with said air conditioning unit; and

a microprocessor operably connected to said power supply and said signal input circuit for controlling application of a high voltage potential to at least one of said field charging unit and said filter unit in response to a signal from said controller.

26. The combination set forth in claim 25 wherein:

said low voltage source comprises a source of eighteen volts to thirty volts AC electric power.

27. The combination set forth in claim 26 wherein:

said controller includes a thermostat for said air conditioning unit.

28. The combination set forth in claim 27 wherein:

said low voltage source comprises a transformer for a control system for said air conditioning unit.

29. The combination set forth in claim 25 wherein:

said control system includes a high voltage monitoring circuit connected to said power supply and said microprocessor for monitoring output voltage from said power supply to said at least one of said field charging unit and said filter unit.

30. The combination set forth in claim 25 including:

a circuit for monitoring current input to said power supply operably connected to said microprocessor.

31. The combination set forth in claim 25 wherein:

said microprocessor is operable to control said power supply to provide high voltage potential to said field charging unit and said filter unit simultaneously in response to said signal from said controller.

32. The combination set forth in claim 25 wherein:

said control system includes a circuit including an interlock switch interposed said low voltage source and said power supply and responsive to movement of an access door for said filtration system to interrupt said low voltage source with respect to said power supply.

33. The combination set forth in claim 25 including:

a power control switch operably connected to said microprocessor for enabling said control system to energize said power supply to supply high voltage potential to said at least one of said field charging unit and said filter unit.

34. The combination set forth in claim 25 including:

a visual display operably connected to said microprocessor for providing visual signals indicating at least one of filter life before requiring servicing of said filter unit, voltage potential output from said power supply and a fault condition of one of said control system and said filtration system.

35. The combination set forth in claim 34 wherein:

said visual display includes multicolored indicators for indicating voltage potential imposed on said at least one of said filter unit and said field charging unit.

36. The combination set forth in claim 25 including:

a switch connected to said microprocessor for resetting a timing function associated with providing a visual display signal indicating requiring servicing of at least one of said filter unit and a prefilter unit associated with said filtration system.

37. In an air filtration system for an air conditioning unit, said filtration system including at least one filter unit mounted on support structure and including an array of passages through which an air flowstream may pass relatively free and through a high voltage electric field for collecting particles on said filter unit from said air flowstream, and an electric field charging unit mounted on said support structure upstream from said filter unit with respect to the direction of airflow through said filtration system, a control system for said filtration system including:

a low voltage source of electric power comprising 18 volts AC to 30 volts AC;

a high voltage power supply operable to be connected to said low voltage source and to said field charging unit and said filter unit;

a thermostat associated with said air conditioning unit and operable by way of a source of from 18 volts AC to 30 volts AC electric power to provide a signal via a signal input circuit; and

a microprocessor operably connected to said power supply and said signal input circuit for controlling application of a high voltage potential to said field charging unit and said filter unit in response to a signal from said thermostat.

38. The combination set forth in claim 37 wherein:

said low voltage source comprises a transformer for a control system for said air conditioning unit.

39. The combination set forth in claim 37 wherein:

said control system includes a circuit including an interlock switch interposed said low voltage source and said power supply and responsive to movement of an access door for said filtration system to interrupt said low voltage source with respect to said power supply.