The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 24, 1982
Filed:
Apr. 03, 1981
Donald W Schoen, St. Paul, MN (US);
Donaldson Company, Inc., Minneapolis, MN (US);
Abstract
The invention is an air purifying apparatus having an air inlet plenum (22, 140) mounted to a filter canister (21) and containing a bypass (63, 157). A barrier (52, 147) divides the inlet plenum (22, 140) into an inlet chamber (53, 150) and an outlet chamber (54, 151). In one embodiment the bypass is formed as a box (63) attached to the plenum (22) and containing openings (70, 71) which communicate respectively with the inlet chamber (53) and the outlet chamber (54) to define a bypass flow path from the inlet chamber (53), through the box (63) and into the outlet chamber (54). In another embodiment the bypass is formed as an opening (157) in the barrier (147) to allow direct communication between the inlet (150) and outlet (151) chambers. The filter canister (21) containing filters (91, 94) is normally hermetically sealed and is mounted to the plenum (22, 140) to allow air flow from the inlet chamber (53, 150), through the filters (91, 94) and into the outlet chamber (54, 151) when the hermetic seal is destroyed and the bypass flow path is occluded. Actuators (125, 126 or 155, 156) in the plenum (22, 140) are operably connected to closures (100, 101) on the filter canister (21). In a first position, the actuators (125, 126 or 155, 156) maintain the hermetically sealed condition of the filter canister (21). In a second position the actuators (125, 126 or 155, 156) destroy the hermetic seal by removing the closures (100, 101) and create an alternate air flow path through the filters (91, 94). The bypass flow path is occluded upon activation of the actuators either by inversion of the box (63) to close its openings (70, 71) or by valves (161, 162) which are carried on the actuators (155, 156) and which close the bypass opening (157) upon removal of the closures (100, 101).