Ever-stand fan

Abstract

This invention discloses an ever-stand fan, including a base and a motor. An upper cover, within which there is an impeller connected with the motor, is arranged over the base. The base has a small flat surface with a curved face on the periphery at the center of its bottom. The motor is mounted in the inner chamber of the base. The center of gravity of the fan lies beneath the center of the base. When the working ever-stand fan tumbles down, the side curve of the base comes into contact with the supporting surface. As the center of gravity of the fan lies beneath the center of the base, the fan can quickly right itself without being helped up by hand.

What is claimed is: 
     
         1 . An ever-stand fan, comprising:
 a base ( 1 ):   a motor ( 2 ); and   an upper cover ( 3 ), within which there is an impeller ( 4 ), connected with the motor ( 2 ), the upper cover ( 3 ) arranged over the base ( 1 ), wherein said base ( 1 ) has a small flat surface ( 11 ) with a curved face ( 12 ) on a periphery at a center of a bottom of the base and the motor ( 2 ) is mounted in an inner chamber of the base ( 1 ), whereby a center of gravity of the ever-stand fan lies beneath a center of the base ( 1 ).   
     
     
         2 . The ever-stand fan according to  claim 1 , further comprising a top cover ( 5 ) arranged over the said upper cover ( 3 ) and a grid ( 51 ) installed on the said top cover ( 5 ) to prevent oddments from going into the impeller ( 4 ). 
     
     
         3 . The ever-stand fan according to  claim 1 , further comprising a shockproof rubber piece ( 6 ) mounted under the small flat surface ( 11 ). 
     
     
         4 . The ever-stand fan according to  claim 1 , wherein an inside surface of the said upper cover ( 3 ) is an Archimedes helicoid, an involute surface, a paraboloid, a hyperboloid or a logarithmic spiral surface and the said inside surface of the upper cover and a peripheral surface of the impeller ( 4 ) form an air duct ( 7 ). 
     
     
         5 . The ever-stand fan according to  claim 1 , wherein the impeller ( 4 ) is of a centrifugal type, comprising several upright blades ( 41 ) distributed around.