CONTROL METHODS FOR SETTING A REFERENCE VOLTAGE IN AN AIR TREATMENT SYSTEM

• US 20170115024A1
• Filed: 01/05/2017
• Published: 04/27/2017
• Est. Priority Date: 07/14/2005
• Status: Active Grant

• Current Assignee: Access Business Group International LLC (Alticor Incorporated)
• Original Assignee: Access Business Group International LLC (Alticor Incorporated)
• Inventors: Evans, Gregory K., Niezgoda, Thomas A., Leppien, Thomas J.
• Granted Patent: US 10,571,394 B2
• Time in Patent Office: Days
• CPC Class Codes: B01D 2267/40 Different types of filters
• CPC Class Codes: B01D 46/0038 with means for influencing the odor, e.g. deodorizing substances
• 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 46/46 automatic
• CPC Class Codes: F24F 11/74 for controlling air flow rate or air velocity
• CPC Class Codes: G01N 21/53 within a flowing fluid, e.g. smoke

Abstract

A control system and associated methods for an air treatment system. In one aspect, the present invention provides a control system and method for controlling blower speed as a function of separately determined smoke and dust concentrations. In one embodiment, the control system and method provides a variable delayed between changes in motor speed to address undesirable rapid changes between speeds. In another aspect, the present invention provides a system and method for calibrating a sensor to provide more uniform operation over time. In yet another aspect, the present invention provide a system and method for calibrating motor speed to provide more consistent and uniform motor speed over time. The present invention also provides a system and method for tracking filter life by as a function of time, motor speed and/or a sensed variable, such as particulate concentration in the environment.

Claims

1. An air treatment system comprising:

a blower motor operable at a plurality of speeds;

a light sensor operable to provide an output; and

a controller operable to;

take a plurality of sample readings from the light sensor,

set a reference voltage as a function of the lowest value from among a plurality of values that are based on the plurality of sample readings, and

control operation of the blower motor based on a subsequent output of the light sensor relative to the reference voltage.

2. The air treatment system of claim 1 wherein the controller is further operable to:

maintain data representative of the plurality of sample readings; and

reset the reference voltage as a function of the average of the data representative of the plurality of sample readings.

3. The air treatment system of claim 1 wherein the controller is operable to store the reference voltage to computer readable memory.

4. The air treatment system of claim 1 wherein the controller is operable to continuously repeat taking a plurality of sample readings from the light sensor.

5. The air treatment system of claim 1 wherein the plurality of sample readings from the light sensor includes 20 readings.

6. The air treatment system of claim 1 wherein the plurality of sample readings from the light sensor are separated from each other by fixed time intervals.

7. The air treatment system of claim 1 wherein the plurality of sample readings from the light sensor are separated from each other by adjustable time intervals.

8. The air treatment system of claim 7 wherein the controller is operable to adjust the time intervals by 5 to 10 millisecond segments.

9. The air treatment system of claim 1 wherein controlling operation of the blower motor includes assigning a light sensor output to a blower speed.

10. The air treatment system of claim 1 wherein controlling operation of the blower motor includes assigning a light sensor output to a sub-range corresponding to a blower speed.

11. An air treatment system comprising:

a blower motor operable at a plurality of blower speeds;

a particulate sensor operable to provide an output voltage; and

a controller operable to control the blower speed based at least partially on the output voltage of the particulate sensor relative to a reference voltage stored to computer readable memory, the controller being further operable to;

receive a plurality of output voltage readings of the particulate sensor, and

reset the reference voltage as a function of the lowest value from among a plurality of values that are based on the plurality of output voltage readings.

12. The air treatment system of claim 11 wherein each of the plurality of values represent an average of a subset of the plurality of output voltage readings.

13. The air treatment system of claim 11 wherein the controller is operable to store the lowest value to computer readable memory as the reset reference voltage.

14. The air treatment system of claim 11 wherein the controller is operable to continuously repeat receiving a plurality of output voltage readings and resetting the reference voltage.

15. The air treatment system of claim 11 wherein the plurality of output voltage readings of the particulate sensor includes 20 readings.

16. The air treatment system of claim 11 wherein the plurality of output voltage readings are separated by fixed time intervals.

17. The air treatment system of claim 11 wherein the plurality of output voltage readings are separated by adjustable time intervals.

18. The air treatment system of claim 17 wherein the controller is operable to adjust the time intervals by 5 to 10 millisecond segments.

19. The air treatment system of claim 11 wherein controlling the blower speed includes assigning a subsequent output voltage reading to a blower speed.

20. The air treatment system of claim 11 wherein controlling the blower speed includes assigning a subsequent output voltage reading to a sub-range corresponding to a blower speed.