Patent ID: 8821129

Claim:
A fan unit ( 1 ) configured to be attached to a filter frame ( 40 ) of a fan ( 4 ) with a fan axis (X-X), the fan unit being a preassembled unit comprising a housing with a cylindrical housing rim ( 22 ), an inlet opening ( 20 ), an outflow opening ( 7 ), and two protective grid structures ( 8 , 21 ) covering the inlet opening ( 20 ) and the outflow opening ( 7 ), and a fan ( 4 ) attached to the housing by a motor mount ( 14 ) which conveys air in at least an axial direction parallel to the fan axis (X-X), the fan ( 4 ) having a fan wheel ( 6 ) formed as one of a diagonal fan wheel and an axial fan wheel, the housing being divided perpendicularly to the fan axis (X-X) in the region of the cylindrical housing rim ( 9 , 22 ) into at least two detachable housing parts connected to one another, one of the housing parts forming a motor bracket ( 2 ) and the other housing part forming an air inlet part ( 3 ), each of the motor bracket ( 2 ) and the air inlet part ( 3 ) formed in one piece with one of the two protective grid structures ( 8 , 21 ), the motor bracket ( 2 ) and the air inlet part ( 3 ) each having a circumference with at least one first mounting flange ( 12 ) with first fastening elements ( 15 , 16 , 17 ) circumferentially arranged on the circumference of the motor bracket ( 2 ) and at least one second mounting flange ( 25 ) with further first fastening elements ( 15 , 16 , 17 ) on the circumference of the air inlet part ( 3 ), the first and second flanges being arranged at an axial distance from each other, the first fastening elements of the motor bracket ( 2 ) and of the air inlet part ( 3 ) being identical ( 15 , 16 , 17 ) and configured to permit an attachment of the fan unit ( 1 ) in two different orientations rotated relative to each other by 180° about an axis perpendicular to the fan axis (X-X), and axially extending spacers ( 28 ) being arranged on axially outward facing surfaces of protective struts or supporting struts of the grid structure and on an axially outward facing surface of a nozzle portion of the inlet part.