Exhaust fan and method of operating the same

Abstract

The present invention provides an exhaust fan including a ventilation grille having a plurality of louvers extending across an exterior face of the grille. Two of the louvers can define an opening and can be oriented such that the interior of the fan is obscured from view of a person through the opening, when the person is positioned in the room such that the person's eyes are outside an area of the room defined by a first reference plane oriented at an angle of less than 25 degrees with respect to a second reference plane and intersecting the second reference plane along a horizontal reference line and a third reference plane oriented at an angle of less than 25 degrees with respect to the second reference plane and intersecting the second reference plane along the horizontal line.

1 . An exhaust fan supported on a ceiling in a room of a structure, the exhaust fan comprising:
 a housing having an air inlet, an air outlet, and an interior positioned between the inlet and the outlet;   a motor and a fan driven by the motor, the fan being supported in the interior of the housing and being operable to move at least 1415 liters per minute of air from the room, through the interior of the housing to a location exterior to the room; and   a ventilation grille extending across the air inlet and having a plurality of louvers extending across an exterior face of the grille, two of the plurality of louvers having an opening therebetween and being oriented such that the interior of the housing is obscured from view of a person through the opening, when the person is positioned in the room such that eyes of the person are outside an area of the room defined by a first reference plane oriented at an angle of less than 25 degrees with respect to a second reference plane and intersecting the second reference plane along a horizontal reference line and a third reference plane oriented at an angle of less than 25 degrees with respect to the second reference plane and intersecting the second reference plane along the horizontal reference line, the horizontal reference line extending through the opening between the at least two louvers, the second reference plane being perpendicular to a floor of the room and extending across the face of the grille in a direction substantially parallel to the two of the plurality of louvers.   
   
   
       2 . The exhaust fan of  claim 1 , wherein a nose of one of the two of the plurality of louvers extends at least partially across the opening. 
   
   
       3 . The exhaust fan of  claim 2 , wherein the nose is oriented at an angle of about 120 degrees with respect to a tail of the louver. 
   
   
       4 . The exhaust fan of  claim 3 , wherein the tail of the louver has a first width in a direction substantially perpendicular to the airflow through the opening and the nose of one of the plurality of louvers has a second width, and wherein the second width is greater than the first width. 
   
   
       5 . The exhaust fan of  claim 1 , wherein the plurality of louvers each include a nose at an exterior end and a tail at an interior end, such that the nose has a greater width than the tail. 
   
   
       6 . The exhaust fan of  claim 1 , wherein the angle is less than 25 degrees. 
   
   
       7 . The exhaust fan of  claim 1 , wherein the louvers are oriented at an angle of between about 60 and about 68 degrees from the second reference plane. 
   
   
       8 . The exhaust fan of  claim 1 , wherein a space between two adjacent louvers has a first length at an interior end and a second length at an exterior end, such that the first length is greater than the second length. 
   
   
       9 . An exhaust fan supported on a ceiling in a room of a structure, the exhaust fan comprising:
 a housing having an air inlet, an air outlet, and an interior positioned between the inlet and the outlet;   a motor and a fan driven by the motor, the fan being supported in the interior of the housing and being operable to move air from the room, through the interior of the housing to a location exterior to the room; and   a ventilation grille extending across the air inlet and having a plurality of louvers extending across an exterior face of the grille, the plurality of louvers each including a nose at an exterior end and a tail at an interior end, such that the nose has a greater width than the tail, the nose extending toward an adjacent louver, two of the plurality of louvers having an opening therebetween and being oriented such that the interior of the housing is obscured from view of a person through the opening, when the person is positioned in the room such that eyes of the person are outside an area of the room defined by a first reference plane oriented at an angle of less than 25 degrees with respect to a second reference plane and intersecting the second reference plane along a horizontal reference line, and a third reference plane oriented at an angle of less than 25 degrees with respect to the second reference plane and intersecting the second reference plane along the horizontal reference line, the horizontal reference line extending through the opening between the at least two louvers, the second reference plane being perpendicular to a floor of the room and extending across the face of the grille in a direction substantially parallel to the two of the plurality of louvers.   
   
   
       10 . The exhaust fan of  claim 9 , wherein a nose of one of the two of the plurality of louvers extends at least partially across the opening. 
   
   
       11 . The exhaust fan of  claim 10 , wherein the nose is oriented at an angle of about 120 degrees with respect to a tail of the louver. 
   
   
       12 . The exhaust fan of  claim 11 , wherein the tail of the louver has a first width in a direction substantially perpendicular to the airflow through the opening and the nose of one of the plurality of louvers has a second width, and wherein the second width is greater than the first width. 
   
   
       13 . The exhaust fan of  claim 9 , wherein the fan moves at least 1415 liters per minute of air from the room, through the plurality of louvers, to a location exterior to the room. 
   
   
       14 . The exhaust fan of  claim 9 , wherein the angle is less than 25 degrees. 
   
   
       15 . The exhaust fan of  claim 9 , wherein the louvers are oriented at an angle of between about 60 and about 68 degrees from the second reference plane. 
   
   
       16 . A method of ventilating a room of a structure, the method comprising the acts of:
 providing a housing having an air inlet, an air outlet, and an interior positioned between the air inlet and air outlet;   driving a fan with a motor to move at least 1415 liters per minute of air from the room, between the plurality of louvers, and through the interior of the housing to a location exterior to the room; and   obscuring the housing interior from view of a person through an opening defined between two of the plurality of louvers with a ventilation grille having an exterior surface and a plurality of louvers oriented at an angle of about 65 degrees with respect to the exterior surface such that when the person is positioned in the room so that eyes of the person are outside an area of the room defined by a first reference plane oriented at an angle of less than 25 degrees with respect to a second reference plane and intersecting the second reference plane along a horizontal reference line and a third reference plane oriented at an angle of less than 25 degrees with respect to the second reference plane and intersecting the second reference plane along the horizontal line the person is unable to see the interior of the housing, the horizontal reference line extending through the opening between the at least two louvers, the second reference plane being perpendicular to a floor of the room and extending across the face of the grille in a direction substantially parallel to the two of the plurality of louvers.   
   
   
       17 . The exhaust fan of  claim 16 , wherein a space between two adjacent louvers has a first length at an exterior end and a second length at an interior end, such that the first length is greater than the second length. 
   
   
       18 . The method of  claim 16 , further comprising orienting the first reference plane at an angle of less than 25 degrees from the second reference plane, and orienting the third reference plane at an angle of less than 25 degrees from the second reference plane. 
   
   
       19 . The exhaust fan of  claim 16 , wherein the plurality of louvers each include a nose at an exterior end and a tail at an interior end, such that the nose has a greater width than the tail. 
   
   
       20 . The method of  claim 16 , wherein a nose of one of the two of the plurality of louvers extends at least partially across the opening, and wherein the nose is oriented at an angle of about 120 degrees with respect to a tail of the louver.