US 11,938,352 B2
Filtering mask assembly
Adel Arigue, Wageningen (NL); and José Tavares, Wageningen (NL)
Assigned to Suzaleja B.V., Wageningen (NL)
Filed by Suzaleja B.V., Wageningen (NL)
Filed on Dec. 17, 2020, as Appl. No. 17/124,494.
Claims priority of provisional application 62/964,703, filed on Jan. 23, 2020.
Prior Publication US 2021/0228920 A1, Jul. 29, 2021
Int. Cl. A62B 23/02 (2006.01); A62B 18/00 (2006.01); A62B 18/02 (2006.01); A62B 18/10 (2006.01)
CPC A62B 23/02 (2013.01) [A62B 18/006 (2013.01); A62B 18/025 (2013.01); A62B 18/10 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A filtering mask assembly configured to be placed over a face of a wearer, the mask assembly comprising:
a housing;
a fan;
an outlet valve;
a filter mounted onto the housing and adapted to substantially follow a shape and contour of the housing to seal the housing from an exterior;
a face seal adapted to be interposed between the face of the wearer and the housing to provide a resilient conformity to the face of the wearer when the filtering mask assembly is worn,
wherein the filtering mask assembly defines an inner space between a mouth and a nose of the wearer and an inner side of the filtering mask assembly, an intermediate space between the housing and the filter, and an outer space separated from the inner space by the filtering mask assembly,
wherein the fan is positioned on a downstream side of the filter to draw air through the filter, and the fan comprises a fan casing having an inlet facing the filter and communicating with the intermediate space between the filter and the housing, and an outlet coaxially opposite the inlet and communicating with the inner space of the filtering mask assembly,
wherein the fan further comprises a fan rotor having a circular plate and a plurality of elongated blades arranged on the circular plate, the fan further comprises an outlet plate, the outlet plate comprising a plurality of outlets that are coaxial with the inlet of the fan casing, each of the plurality of elongated blades extend from a first surface of the circular plate and each of the plurality of elongated blades are arranged radially and substantially perpendicular on the first surface of the circular plate, wherein each of the plurality of elongated blades comprises a length that extends between a central portion of the circular plate and a curved surface of the circular plate, and the plurality of elongated blades are positioned between the first surface and the inlet, and the circular plate further comprises a second surface that is opposite of the first surface, the second surface is configured to face an inner surface of the outlet plate, and wherein the fan is releasably attached to the housing,
wherein an inner diameter of the fan casing is adapted to increase from the inlet towards the outlet to generate a pressure increase from the inlet towards the outlet to compensate for a pressure drop through the filter, and
wherein, when in use, the outlet valve is adapted to open to expel substantially all exhaled air from the inner space to the outer space when air pressure inside the inner space is greater than air pressure in the outer space and to remain closed when the pressure in the inner space is lower than the pressure in the outer space, thereby preventing the breathing of any air which has not passed through the filter.