Patent ID: 11884135
Assignee: DES DEVELOPEMENT LLC
Field: Chemical engineering (Chemistry)
Classification: CPC B | IPC B

Claim 0:
1. An air filtration system for a mobile unit having a vent fan secured to a roof of the mobile unit, wherein the vent fan includes a vent fan housing, a vent fan cover and a perimeter flange around the vent fan housing, comprising:
a flat base plate having a central opening that is positionable around a perimeter of the vent fan housing and over a top of the perimeter flange, wherein the flat base plate is secureable to the mobile unit with screws having a length to extend through the flat base plate, through the perimeter flange, and into the roof of the mobile unit;
a filter box including five rectangular air filters secured together in the shape of a box having four filter sidewalls and a filter top, wherein the filter box has an open bottom so that the four filter sidewalls are positionable around the vent fan housing with the filter top extending over the vent fan and the four filter sidewalls configured to sit flush on top of the flat base plate, and wherein the filter box is configured to avoid interfering with opening and closing of the vent fan cover; and
a rigid outer cover having a bottom edge that is hingedly secured to the flat base plate with the rigid outer cover extending over the vent fan, wherein the rigid outer cover is configured to receive the filter box in an operable position with a lower edge of the filter box flush against the flat base plate while avoiding interference with opening and closing of the vent fan cover, wherein the rigid outer cover includes an air inlet passageway to an air flow space between the rigid outer cover and the filter box, and wherein the rigid outer cover can be opened for receiving the filter box and can be securely closed to retain the filter box in an operable position.