Residual life indicating system

• US 20050188749A1
• Filed: 02/24/2005
• Published: 09/01/2005
• Est. Priority Date: 02/27/2004
• Status: Active Grant

• Current Assignee: HDT Expeditionary Systems, Inc. (HDT Global, Inc.)
• Original Assignee: Hunters Manufacturing Co Incorporated (Hunter's Manufacturing Company Incorporated)
• Inventors: Creed, John L., Kessler, Kenneth L., Harel, Reuben, Custer, John P.
• Granted Patent: US 7,201,036 B2
• Time in Patent Office: Days
• US Class Current: 73/38
• CPC Class Codes: B01D 46/0086 Filter condition indicators
• CPC Class Codes: B01D 46/442 by measuring the concentration of particles
• CPC Class Codes: B01D 53/0454 Controlling adsorption controlling temperature swing adsorption B01D53/0462, controlling pressure swing adsorption B01D53/047

Abstract

A residual life indicating system for a filter includes a main filter, a sampling filter, and a sensor. Both the main filter and the sampling filter receive an ambient gas meant to be filtered. The sensor connects to the sampling filter and senses the presence of a predetermined chemical in the gas that has been filtered by the sampling filter.

Claims

1. A residual life indicating system for a filter, comprising:

a main filter;

a sampling filter, wherein said main filter and said sampling filter both receive an ambient gas meant to be filtered;

a sensor connected to said sampling filter wherein said sensor senses the presence of a predetermined chemical in the gas which has been filtered by said sampling filter.

2. The system of claim 1 further comprising a heater mounted to said sampling filter for heating same.

3. The system of claim 1 wherein said sensor is positioned downstream from said sampling filter.

4. The system of claim 1 further comprising a microprocessor electrically connected to said sensor.

5. The system of claim 1 further comprising a second sampling filter, spaced from said first sampling filter.

6. The system of claim 5 wherein said second sampling filter is in series with said first sampling filter.

7. The system of claim 5 wherein said second sampling filter is in parallel with said first sampling filter.

8. The system of claim 1 further comprising an gas source for supplying a gas to said main filter and said sampling filter.

9. The system of claim 1 wherein said main filter has a volume which is larger than a volume of said sampling filter.

10. A residual life indicating system for a filter in a gas purification assembly, comprising:

a main filter;

a sampling filter spaced from said main filter, wherein said main filter and said sampling filter each receive an ambient gas meant to be filtered;

an accumulator located downstream from said sampling filter and in fluid communication therewith;

a sensor connected to said accumulator, said sensor sensing the presence of a predetermined chemical in the gas which has been filtered by said sampling filter and has entered said accumulator.

11. The system of claim 10 further comprising a heater mounted to said accumulator for heating same.

12. The system of claim 10 wherein said sensor is positioned downstream from said accumulator.

13. The system of claim 10 further comprising a microprocessor electrically connected to said sensor.

14. The system of claim 10 further comprising a second sampling filter, spaced from said first sampling filter.

15. The system of claim 14 wherein said second sampling filter is in series with said first sampling filter.

16. The system of claim 14 wherein said second sampling filter is in parallel with said first sampling filter.

17. The system of claim 10 further comprising an gas source for supplying a gas to said main filter and said sampling filter.

18. The system of claim 10 wherein said accumulator has a volume which is smaller than a volume of said sampling filter.

19. The system of claim 10 wherein said sampling filter has a volume which is smaller than a volume of said main filter.

20. An air purification assembly comprising:

an air flow path;

an air pressurizing member located in said air flow path for supplying pressurized ambient air;

a main filter located in said air flow path for filtering the pressurized ambient air flowing along said air flow path;

a sampling filter in fluid communication with said air flow path via an orifice for sampling the pressurized ambient air;

a sensor communicating with said sampling filter for sensing the presence of a predetermined chemical in the air exiting said sampling filter.

21. The system of claim 20 further comprising a heater mounted to said sampling filter for heating same.

22. The system of claim 20 wherein said sensor is positioned downstream from said sampling filter.

23. The system of claim 20 further comprising a microprocessor electrically connected to said sensor.

24. The system of claim 20 wherein said main filter has a volume which is larger than a volume of said sampling filter.

25. The system of claim 20 further comprising a second sampling filter, spaced from said first sampling filter.

26. The system of claim 25 wherein said second sampling filter is in series with said first sampling filter.

27. The system of claim 25 wherein said second sampling filter is in parallel with said first sampling filter.

28. A residual life indicating system for a filter, comprising:

a main filter;

a sampling filter, wherein said main filter and said sampling filter both receive an ambient gas meant to be filtered;

a supply of a pressurized challenge gas;

a conduit for connecting said challenge gas supply to said sampling filter;

a regulator for regulating a flow of the challenge gas to said sampling filter; and

,

a sensor located downstream from said sampling filter wherein said sensor senses the presence of a predetermined chemical in the gas which has been filtered by said sampling filter.

29. The system of claim 28 wherein said regulator comprises a metering solenoid.

30. The system of claim 29 further comprising a microprocessor electrically connected to said sensor.

31. The system of claim 30 wherein said microprocessor is electrically connected to said metering solenoid.

32. The system of claim 31 further comprising a valve which is located in said conduit for regulating a flow of the ambient gas and the challenge gas to said sampling filter.

33. The system of claim 32 wherein said microprocessor is electrically connected to said valve.

34. The system of claim 33 further comprising a second sampling filter, spaced from said first sampling filter.

35. The system of claim 34 wherein said second sampling filter is in series with said first sampling filter.

36. The system of claim 34 wherein said second sampling filter is in parallel with said first sampling filter.