Filter sensor

• US 9,120,043 B2
• Filed: 05/30/2006
• Issued: 09/01/2015
• Est. Priority Date: 05/30/2006
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Johansson, Ronald C., Bharti, Vivek
• Primary Examiner(s): Greene, Jason M
• Assistant Examiner(s): SHUMATE, ANTHONY R
• Application Number:
  US11/420,949
• Publication Number:
  US 20070277592A1
• Time in Patent Office: 3,381 Days
• Field of Search: 964/17, 964/21, 964/22, 55D/IG.34
• US Class Current: 1/1
• CPC Class Codes: B01D 46/0086 Filter condition indicators
• CPC Class Codes: B01D 46/10 Particle separators, e.g. dust precipitators, using filter plates, sheets or pads having plane surfaces
• CPC Class Codes: B01D 46/444 by flow measuring

Abstract

A filter life sensor assembly within an air handling system is disclosed. The air handling system includes an air flow intake, an air flow exit, and a filter disposed between the air flow intake and air flow exit. The filter sensor assembly comprises a bypass connecting the air flow intake to the air flow exit, a dielectric sensor adjacent the bypass, wherein the dielectric sensor generates an electrical signal in response the air flow passing through the bypass.

Claims

1. A filter life sensor assembly within an air handling system which includes an air flow intake, an air flow exit, and a filter disposed between the air flow intake and air flow exit, the filter life sensor assembly comprising:

a bypass connecting the air flow intake to the air flow exit;

a dielectric sensor adjacent the bypass;

wherein the dielectric sensor generates an electrical signal in response to the air flow passing through the bypass,

and wherein the filter life sensor assembly transmits an output signal indicative of the filter condition, the output signal resulting from a measurement of air flow passing through the bypass and not resulting from a measurement of air flow passing through the filter.

2. The filter life sensor assembly of claim 1, wherein the dielectric sensor is a piezoelectric sensor.

3. The filter life sensor assembly of claim 1, further comprising a battery.

4. The filter life sensor assembly of claim 3, wherein the battery is a rechargeable battery.

5. The filter life sensor assembly of claim 1, further comprises a circuit that is generating power by actuation of the dielectric sensor.

6. The filter life sensor assembly of claim 1, wherein the dielectric sensor further comprises a signal transmitter to communicate the output signal with a relay box.

7. The filter life sensor assembly of claim 6, wherein the signal transmitter is a wire connecting the dielectric sensor to the relay box.

8. The filter life sensor assembly of claim 6, wherein the signal transmitter is a radio frequency transmitter transmitting from the dielectric sensor to the relay box.

9. The filter life sensor assembly of claim 6, wherein the relay box determines a condition of the filter based on the output signal.

10. The filter life sensor assembly of claim 7, wherein the relay box connects with a display to display the condition of the filter.

11. The filter life sensor assembly of claim 8, wherein the relay box connects with a display to display the condition of the filter.

12. The filter life sensor assembly of claim 11, wherein the filter comprises a frame surrounding a filter media and the bypass extends through the frame of the filter.

13. The filter life sensor assembly of claim 11, wherein the filter comprises a frame surrounding a filter media and the bypass extends through the filter media of the filter.

14. The filter life sensor assembly of claim 1, wherein the bypass extends through a portion of the air handling system.

15. The filter life sensor assembly of claim 1, wherein the air handling system is a furnace, room air purifier, air conditioner, or respirator.