Heat dissipation apparatus and fan frame thereof

Abstract

A heat dissipation apparatus. A fan frame accommodates an impeller therein and includes an air inlet, an air outlet, and a passage for guiding airflow from the air inlet to the air outlet. An inner peripheral wall of the passage radially and outwardly extends a smooth curved expansion portion at the air outlet. The curved expansion portion includes a recess in which the airflow forms an airflow layer, stopping subsequent airflow from directly contacting the inner peripheral wall of the passage.

1 . A fan frame for a heat dissipation apparatus, comprising: 
 a casing comprising a passage for guiding airflow from one opening to another opening, wherein the casing further comprises a smooth curved expansion portion being radially and outwardly extended from an inner peripheral wall of the passage at either one or both openings.    
   
   
       2 . The fan frame as claimed in  claim 1 , wherein the curved expansion portion further comprises a recess in which the airflow forms an airflow layer, stopping subsequent airflow from directly contacting the inner peripheral wall of the passage.  
   
   
       3 . The fan frame as claimed in  claim 1 , wherein the openings are an air inlet and an air outlet, and the smooth curved expansion portion is radially and outwardly extended from the inner peripheral wall of the passage at the air outlet.  
   
   
       4 . The fan frame as claimed in  claim 3 , wherein the curved expansion portion at the air outlet is radially and outwardly extended out of the casing and is symmetrical with respect to an axis of the passage.  
   
   
       5 . The fan frame as claimed in  claim 3 , wherein the curved expansion portion at the air outlet has a tapered angle, a bevel angle, a tapered bevel angle, or a large R angle.  
   
   
       6 . The fan frame as claimed in  claim 3 , wherein the casing further comprises another smooth curved expansion portion, being radially and outwardly extended from the inner peripheral wall of the passage at the air inlet, which is symmetrical with respect to an axis of the passage.  
   
   
       7 . The fan frame as claimed in  claim 3 , wherein the smooth curved expansion portion is radially and outwardly extended out of the casing from the inner peripheral wall of the passage at the air inlet and is symmetrical with respect to an axis of the passage.  
   
   
       8 . The fan frame as claimed in  claim 3 , wherein the smooth curved expansion portion is radially and outwardly extended from the inner peripheral wall of the passage at the air inlet in a circular or elliptical shape with respect to an axis of the passage.  
   
   
       9 . The fan frame as claimed in  claim 3 , wherein the inner peripheral wall of the passage at the air inlet has a tapered angle, a bevel angle, a tapered bevel angle, or a large R angle and is symmetrical with respect to an axis of the passage.  
   
   
       10 . A heat dissipation apparatus, comprising: 
 an impeller; and    a fan frame for accommodating the impeller therein and comprising a passage for guiding airflow from one opening to another opening, wherein the fan frame further comprises a smooth curved expansion portion being radially and outwardly extended from an inner peripheral wall of the passage at either one or both openings.    
   
   
       11 . The heat dissipation apparatus as claimed in  claim 10 , wherein the curved expansion portion further comprises a recess in which the airflow forms an airflow layer, stopping subsequent airflow from directly contacting the inner peripheral wall of the passage.  
   
   
       12 . The heat dissipation apparatus as claimed in  claim 10 , wherein the openings are an air inlet and an air outlet, and the smooth curved expansion portion is radially and outwardly extended from the inner peripheral wall of the passage at the air outlet.  
   
   
       13 . The heat dissipation apparatus as claimed in  claim 10 , wherein the length of blades of the impeller is increased corresponding to the radially and outwardly extended curved expansion portion.  
   
   
       14 . The heat dissipation apparatus as claimed in  claim 10 , wherein the heat dissipation apparatus is an axial flow fan.  
   
   
       15 . The heat dissipation apparatus as claimed in  claim 10 , further comprising a motor base disposed in the fan frame, wherein the impeller is disposed on the motor base, and the motor base comprises a slope inclined radially, thereby increasing areas of air flow intake or discharge.  
   
   
       16 . The heat dissipation apparatus as claimed in  claim 15 , wherein the slope is flat or curved.  
   
   
       17 . A heat dissipation system, comprising: 
 a system housing;    at least one electronic device, disposed in the system housing; and    a heat dissipation apparatus applied to the system housing for dissipating heat generated by the electronic device, wherein the heat dissipation apparatus comprises an impeller and a fan frame for accommodating the impeller therein, the fan frame comprises a passage for guiding airflow from one opening to another opening, and the fan frame further comprises a smooth curved expansion portion being radially and outwardly extended from an inner peripheral wall of the passage at either one or both openings.    
   
   
       18 . The heat dissipation system as claimed in  claim 17 , wherein the curved expansion portion further comprises a recess in which the airflow forms an airflow layer, stopping subsequent airflow from directly contacting the inner peripheral wall of the passage.  
   
   
       19 . The heat dissipation system as claimed in  claim 17 , wherein the openings are an air inlet and an air outlet, and the casing further comprises a smooth curved expansion portion being radially and outwardly extended from the inner peripheral wall of the passage at the air outlet.  
   
   
       20 . The heat dissipation system as claimed in  claim 19 , wherein the curved expansion portion at the air outlet has a tapered angle, a bevel angle, a tapered bevel angle, or a large R angle.