Centrifugal fan

Abstract

A centrifugal fan includes a housing, a spiral impeller, a suction interrupting member. The housing includes a suction port and a discharge port. The housing further includes an outwardly curved cutoff portion at a side of the discharge port. The spiral impeller is coupled with a motor to suck air through the suction port of the housing in a rotation-axis direction and discharge the sucked air through the discharge port in a direction perpendicular to a rotation-axis. The suction interrupting member prevents air from being sucked into a neighborhood of the cutoff portion through the suction port.

1 . A centrifugal fan comprising:
 a housing comprising a suction port, a discharge port and a cutoff portion for dividing an air flow;   a spiral impeller coupled with a motor to suck air through the suction port of the housing in a rotation-axis direction and discharge the sucked air through the discharge port in a direction perpendicular to a rotation-axis; and   a suction interrupting member preventing air from being sucked into a neighborhood of the cutoff portion through the suction port,   wherein the housing further comprises an outwardly curved cutoff portion at a side of the discharge port.   
   
   
       2 . The centrifugal fan of  claim 1 , wherein the suction interrupting member extends from an inner surface of the suction port adjacent to the cutoff portion in the direction perpendicular to the rotation-axis. 
   
   
       3 . The centrifugal fan of  claim 1 , wherein at least one of: one suction port and two suction ports, each facing the impeller, are provided. 
   
   
       4 . The centrifugal fan of  claim 1 , wherein an external air discharge passage of the housing has a spiral shape with respect to the rotation-axis. 
   
   
       5 . The centrifugal fan of  claim 1 , wherein the impeller comprises curved blades extending radially outward. 
   
   
       6 . The centrifugal fan of  claim 1 , wherein the motor is installed outside the housing to rotate the impeller using a power transmission unit. 
   
   
       7 . A computer cooling fan comprising:
 a housing comprising a suction port, a discharge port and an outwardly curved cutoff portion at a side of the discharge port;   a spiral impeller coupled with a motor to suck air through the suction port of the housing in a rotation-axis direction and discharge the sucked air through the discharge port in a direction perpendicular to a rotation-axis; and   a suction interrupting member preventing air from being sucked into a neighborhood of the cutoff portion through the suction port.   
   
   
       8 . The computer cooling fan of  claim 7 , wherein the suction interrupting member extends from an inner surface of the suction port adjacent to the cutoff portion in the direction perpendicular to the rotation-axis. 
   
   
       9 . The computer cooling fan of  claim 7 , wherein at least one of: one suction port and two suction ports, each facing the impeller, are provided. 
   
   
       10 . The computer cooling fan of  claim 7 , wherein an external air discharge passage of the housing has a spiral shape with respect to the rotation-axis. 
   
   
       11 . The computer cooling fan of  claim 7 , wherein the impeller comprises curved blades extending radially outward. 
   
   
       12 . A fan comprising:
 a housing including at least a suction port and a discharge port, said discharge port including an outwardly curved cutoff portion;   a spiral impeller for draw air through the suction port in a rotation-axis direction and discharge air through the discharge port in a direction perpendicular to a rotation-axis;   a motor connected to said spiral impeller for driving said impeller; and   a suction interrupting member preventing air from being sucked into a neighborhood of said cutoff portion through the suction port.   
   
   
       13 . The fan of  claim 12 , wherein the suction interrupting member extends from an inner surface of the suction port adjacent to the cutoff portion in the direction substantially perpendicular to the rotation-axis. 
   
   
       14 . The fan of  claim 12 , wherein at least one of: one suction port and two suction ports, each facing the impeller, are provided. 
   
   
       15 . The fan of  claim 12 , wherein an external air discharge passage of the housing has a spiral shape with respect to the rotation-axis. 
   
   
       16 . The fan of  claim 12 , wherein the impeller comprises curved blades extending radially outward.