Fans and fan frames

Abstract

A fan with a fan frame and an impeller. The fan frame includes a housing and a motor base. The housing includes a passage. The passage forms an air outlet and an air inlet on both ends of the housing. The motor base is disposed in the housing. The impeller is disposed on the motor base. When the motor base is at the air outlet or the air inlet, the bottom of the motor base locates on a plane different from that of the air outlet or the air inlet. The motor base is raised into the housing, increasing the area of air flow intake or discharge. Additionally, during the operation of the fan, noise, caused by vibrations generated by rotation of the impeller and transferred to an exterior system via the motor base, can be reduced.

1 . A fan frame, comprising: 
 a housing having a passage which forms an air outlet and an air inlet on both ends of the housing; and    a motor base disposed in the housing, wherein when the motor base is at the air outlet or the air inlet, a bottom of the motor base locates on a plane different from that of the air outlet or the air inlet.    
   
   
       2 . The fan frame as claimed in  claim 1 , further comprising a plurality of ribs disposed between the housing and the motor base to support the motor base, wherein a cross section of each rib is varied along a direction from the motor base to the housing.  
   
   
       3 . The fan frame as claimed in  claim 2 , wherein a width of each rib is varied along the direction from the motor base to the housing, or the width of each rib gradually increases or decreases along the direction of from the motor base to the housing.  
   
   
       4 . The fan frame as claimed in  claim 3 , wherein the width of each rib connecting to the motor base and housing is relatively greater or less than that of a central part of the rib.  
   
   
       5 . The fan frame as claimed in  claim 2 , wherein a thickness of each rib is varied from along the direction of the motor base to the housing, or the thickness of each rib gradually increases or decreases along the direction of from the motor base to the housing.  
   
   
       6 . The fan frame as claimed in  claim 5 , wherein the thickness of each rib connecting to the motor base and housing is relatively greater or less than that of a central part of the rib.  
   
   
       7 . The fan frame as claimed in  claim 2 , wherein the housing further comprises an outward expansion portion at the air outlet or the air inlet to increase an area of air flow intake or discharge.  
   
   
       8 . The fan frame as claimed in  claim 7 , wherein the ribs are connected to the outward expansion portion, and the outward expansion portion is formed with a lead angle, a sloped angle, a lead and sloped angle, or a curved angle.  
   
   
       9 . The fan frame as claimed in  claim 2 , wherein the motor base comprises a slope inclined radially to adjust an area of air flow intake or discharge, and the slope is linear or curved.  
   
   
       10 . A fan, comprising: 
 a fan frame comprising: 
 a housing having a passage which forms an air outlet and an air inlet on both ends of the housing; and  
 a motor base disposed in the housing; and  
   an impeller disposed on the motor base, wherein when the motor base is at the air outlet or the air inlet, a bottom of the motor base locates on a plane different from that of the air outlet or the air inlet.    
   
   
       11 . The fan as claimed in  claim 10 , wherein the fan is applied to a light source, a periphery of the passage comprises an inner surface, and when light emitted by the light source enters the passage, the light is blocked from penetrating the passage by the inner surface.  
   
   
       12 . The fan as claimed in  claim 11 , wherein the inner surface is a concave surface depressed toward a central axis of the passage so as to block the light emitted by the light source.  
   
   
       13 . The fan as claimed in  claim 11 , wherein the inner surface is a convex surface protruded toward a central axis of the passage, an outer edge of the impeller is formed with a concave surface opposing the curved surface so as to block the light emitted by the light source.  
   
   
       14 . The fan as claimed in  claim 11 , wherein the outer edge of the impeller is parallel to the curved surface of the periphery of the passage.  
   
   
       15 . The fan as claimed in  claim 11 , wherein the inner surface comprises a gradually shrinking surface and a gradually expanding surface.  
   
   
       16 . The fan as claimed in  claim 11 , wherein the inner surface comprises a radially- and gradually shrinking curved surface and a radially and gradually expanding curved surface, both of which have different curvatures.  
   
   
       17 . The fan as claimed in  claim 11 , wherein a maximum outer diameter of the outer edge of the impeller exceeds a minimum inner diameter of the periphery of the passage.  
   
   
       18 . The fan as claimed in  claim 11 , wherein the impeller comprises blades with flat, conical, curved or stepped edges.  
   
   
       19 . The fan as claimed in  claim 10 , wherein each blade of the impeller overlaps an adjacent blade in an axial direction of the passage.  
   
   
       20 . The fan as claimed in  claim 10 , wherein the motor base is a part of a system having a fan assembly or the motor base forms a casing sidewall of a system.