Fan and selecting method for motor size thereof

Abstract

A fan includes a frame, an impeller and a motor. The impeller is accommodated in the frame. The motor connects and drives the impeller to rotate, and includes a rotor structure and a stator structure. The dimension Y of the frame and the diameter X of the stator structure meet the equation of Y=CXn′ wherein C is a constant, and n is a variable number. A selecting method for motor size of the fan is also disclosed.

1 . A fan comprising:
 a frame;   an impeller accommodated in the frame; and   a motor driving the impeller and comprising a rotor structure and a stator structure;   wherein a dimension Y of the frame and a diameter X of the stator structure meet an equation of Y=CX n , where C is a constant and n is a variable number.   
   
   
       2 . The fan of  claim 1 , wherein Y is greater than or equal to 0.04 m and smaller than or equal to 0.12 m. 
   
   
       3 . The fan of  claim 1 , wherein the equation is Y=13.25X 1.4 ±5%. 
   
   
       4 . The fan of  claim 1 , wherein n is greater than 1 and smaller than 2. 
   
   
       5 . The fan of  claim 1 , wherein the fan has a thickness greater than or equal to 1.5 inches. 
   
   
       6 . The fan of  claim 1 , wherein the impeller includes a hub and a plurality of blades disposed around the hub. 
   
   
       7 . The fan of  claim 1 , wherein the fan is an axial-flow fan. 
   
   
       8 . The fan of  claim 1 , wherein a ratio of the diameter X of the stator structure to the dimension Y of the frame ranges between 25% and 50%. 
   
   
       9 . The fan of  claim 1 , wherein the rotor structure includes a magnetically conductive shell, a magnetic element, and a shaft, the magnetic element is disposed on an inner surface of the magnetically conductive shell corresponding to the stator structure, the shaft is coupled to the magnetically conductive shell, and the magnetically conductive shell connects to a hub of the impeller. 
   
   
       10 . The fan of  claim 9 , wherein the stator structure has an axial hole and the shaft of the rotor structure is inserted through the axial hole. 
   
   
       11 . A method for selecting the motor size of a fan, comprising the steps of: a
 providing a frame with a dimension Y and a stator structure with a diameter X; and   obtaining the diameter X of the stator structure or the dimension Y of the frame according to an equation of Y=CX n ;   wherein C is a constant and n is a variable number.   
   
   
       12 . The method of  claim 11 , wherein Y is greater than or equal to 0.04 m and smaller than or equal to 0.12 m. 
   
   
       13 . The method of  claim 11 , wherein the equation is Y=13.25X 1.4 ±5%. 
   
   
       14 . The method of  claim 11 , wherein n is greater than 1 and smaller than 2. 
   
   
       15 . The method of  claim 11 , wherein the fan has a thickness greater than or equal to 1.5 inches. 
   
   
       16 . The method of  claim 11 , wherein a ratio of the diameter X of the stator structure to the dimension Y of the frame ranges between 25% and 50%. 
   
   
       17 . The method of  claim 11 , wherein the rotor structure includes a magnetically conductive shell, a magnetic element, and a shaft, the magnetic element is disposed on an inner surface of the magnetically conductive shell corresponding to the stator structure, the shaft is coupled to the magnetically conductive shell, and the magnetically conductive shell connects to a hub of the impeller. 
   
   
       18 . The method of  claim 17 , wherein the stator structure has an axial hole and the shaft of the rotor structure is inserted through the axial hole. 
   
   
       19 . The method of  claim 11 , wherein the fan is an axial-flow fan.