Portable industrial air filtration device

• US 9,776,117 B2
• Filed: 03/07/2014
• Issued: 10/03/2017
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Illinois Tool Works Inc.
• Original Assignee: Illinois Tool Works Inc.
• Inventors: Grider, Keith A., Leatzow, Derek J., McPhilliamy, Stephen J., Belton, Antonio J., White, Jr., John S., Greene, Daniel J., Francis, Ryan L., Corrigan, Sean J., Pint, Charles Steven, Garrett, Jr., Frank E.
• Primary Examiner(s): Orlando, Amber R
• Assistant Examiner(s): Precht, Brittany
• Application Number:
  US14/200,879
• Publication Number:
  US 20140260996A1
• Time in Patent Office: 1,306 Days
• CPC Class Codes: B01D 2273/30 Means for generating a circulation of a fluid in a filtration system, e.g. using a pump or a fan
• CPC Class Codes: B01D 46/0004 Details of removable closures, lids, caps or filter heads
• CPC Class Codes: B01D 46/0041 for feeding
• CPC Class Codes: B01D 46/0086 Filter condition indicators
• CPC Class Codes: B01D 46/30 Particle separators, e.g. dust precipitators, using loose filtering material
• CPC Class Codes: B01D 46/44 controlling filtration
• CPC Class Codes: B01D 46/444 by flow measuring
• CPC Class Codes: B01D 46/446 by pressure measuring
• CPC Class Codes: B01D 46/46 automatic
• CPC Class Codes: B01D 46/64 arranged concentrically or coaxially

Abstract

Various embodiments of the present disclosure provide a portable industrial air filtration device employing an annular dual filter assembly to capture and remove impurities from the air surrounding the air filtration device, enabling the air filtration device to quickly and efficiently improve the quality and safety of the air. The air filtration device includes a two-piece housing including a lower housing component and a locking cover removably attachable to the lower housing component. The dual filter assembly is mounted within the housing between the locking cover and the lower housing component, and includes a removable self-supporting outer pre-filter surrounding a separately removable inner HEPA filter. The pre-filter initially filters the surrounding air by capturing relatively large or coarse impurities, and the HEPA filter further filters the air pulled through the pre-filter by capturing relatively small or fine impurities.

Claims

1. An air filtration device comprising:

a housing;

at least one filter supported by the housing;

a fan supported by the housing; and

a controller supported by the housing, the controller configured to;

(a) at a first point in time, determine a current fan speed setting;

(b) responsive to determining, at the first point in time, that the current fan speed setting is a first designated fan speed setting associated with a first desired air flow rate;

(i) determine a first desired fan speed based, at least in part, on a differential pressure across the fan and the first desired air flow rate;

(ii) determine whether the first desired fan speed is less than or equal to a maximum allowable fan speed; and

(iii) responsive to determining that the first desired fan speed is less than or equal to the maximum allowable fan speed, cause the fan to operate at the first desired fan speed; and

(c) responsive to determining, at the first point in time, that the current fan speed setting is a second designated fan speed setting associated with a second desired air flow rate different from the first desired air flow rate;

(i) determine a second desired fan speed based, at least in part, on the differential pressure across the fan and the second desired air flow rate;

(ii) determine whether the second desired fan speed is less than or equal to the maximum allowable fan speed; and

(iii) responsive to determining that the second desired fan speed is less than or equal to the maximum allowable fan speed, cause the fan to operate at the second desired fan speed.

2. The air filtration device of claim 1, wherein the controller is further configured to, responsive to determining that the first desired fan speed is greater than the maximum allowable fan speed, cause the fan to operate at the maximum allowable fan speed.

3. The air filtration device of claim 1, which includes one or more pressure sensors, and wherein the controller is further configured to determine the differential pressure across the fan using feedback from the one or more pressure sensors.

4. The air filtration device of claim 1, wherein the one or more pressure sensors include a fan differential pressure sensor configured to measure the differential pressure across the fan.

5. The air filtration device of claim 4, wherein the fan differential pressure sensor includes a first port connected to a first pressure sensor port of the housing and a second different port connected to a second different pressure sensor port of the housing, wherein the first pressure sensor port of the housing is located upstream of the fan and the second pressure sensor port of the housing is located downstream of the fan.

6. The air filtration device of claim 1, wherein the controller is further configured to, responsive to determining, at the first point in time, that the current fan speed setting is a non-designated fan speed setting, cause the fan to operate at a designated fan speed.

7. The air filtration device of claim 1, wherein the controller is further configured to repeat (a) to (c) at a second point in time upon an expiration of a fan speed determination time interval.

8. The air filtration device of claim 1, wherein the controller is further configured to determine the first desired fan speed independent of an occlusion level of any of the at least one filter.

9. The air filtration device of claim 1, wherein the housing includes a lower housing component and a locking cover removably attachable to the lower housing component.

10. The air filtration device of claim 9, wherein the at least one filter includes a removable exterior pre-filter and a separately removable inner high-efficiency particulate air filter, wherein the pre-filter is mounted within the housing between the locking cover and the lower housing component and the high-efficiency particulate air filter is mounted within the pre-filter between the locking cover and the lower housing component.

11. The air filtration device of claim 10, wherein the fan is mounted to the housing below the pre-filter and the high-efficiency particulate air filter.

12. The air filtration device of claim 10, wherein the lower housing component includes a sealing surface and the high-efficiency particulate air filter includes an end cap that sealingly engages the sealing surface when the locking cover is attached to the lower housing component.

13. The air filtration device of claim 9, wherein the lower housing component includes a plurality of upwardly-extending stabilizers.

14. The air filtration device of claim 13, wherein the locking cover is removably attachable to the plurality of stabilizers.

15. The air filtration device of claim 1, which includes an exhaust port in fluid communication with the fan.

16. The air filtration device of claim 15, wherein the at least one filter includes a removable exterior pre-filter and a separately removable inner high-efficiency particulate air filter.

17. The air filtration device of claim 16, wherein the exhaust port is below the pre-filter and the high-efficiency particulate air filter.

18. The air filtration device of claim 17, wherein a longitudinal axis of the exhaust port is approximately perpendicular to longitudinal axes of the pre-filter and the high-efficiency particulate air filter, and the housing includes a lower housing component including a plurality of upwardly-extending stabilizers and the exhaust port is adjacent one of the stabilizers.

19. An air filtration device comprising:

a housing including a lower housing component and a locking cover removably attachable to the lower housing component;

at least one filter supported by the housing;

a fan supported by the housing; and

a controller supported by the housing, the controller configured to;

(a) at a first point in time, determine a current fan speed setting;

(b) responsive to determining, at the first point in time, that the current fan speed setting is one of at least one designated fan speed setting associated with a desired air flow rate;

(i) determine a desired fan speed based, at least in part, on a differential pressure across the fan and the desired air flow rate;

(ii) determine whether the first desired fan speed is less than or equal to a maximum allowable fan speed;

(iii) responsive to determining that the desired fan speed is less than or equal to the maximum allowable fan speed, cause the fan to operate at the desired fan speed; and

(iv) responsive to determining that the desired fan speed is greater than the maximum allowable fan speed, cause the fan to operate at the maximum allowable fan speed; and

(c) responsive to determining, at the first point in time, that the current fan speed setting is a non-designated fan speed setting, cause the fan to operate at a designated nonzero fan speed.

20. An air filtration device comprising:

a housing;

a filter supported by the housing;

a fan supported by the housing;

a pressure sensor supported by the housing;

an operating mode selector configured to enable selection of a first operational mode, a second operational mode, or an off mode; and

a controller supported by the housing and configured to, after receiving feedback from the operating mode selector indicating that the first operational mode has been selected;

determine a desired fan speed based at least in part on a differential pressure across the fan and the desired air flow rate;

determine whether the desired fan speed exceeds a maximum allowable fan speed; and

responsive to determining that the desired fan speed does not exceed the maximum allowable fan speed, cause the fan to operate at the desired fan speed.