Fan blade and shaft assembly mounting arrangement of a bathroom exhaust fan

Abstract

A fan blade and shaft mounting arrangement for bathroom exhaust fan includes a housing, a fan blade which has a hub, a center tube at the center of the hub and blades arranged around the hub, a fan shaft inserted through the center tube of the fan blade and supported between two bearing members in the housing, and a torsion spring that has a torsionable portion sleeved onto the fan shaft and a positioning portion fastened to the fan blade. When the fan shaft is rotated, the torsionable portion of the torsion spring is twisted and secured firmly to the fan shaft so that the fan blade is rotated with the fan shaft.

1 . A fan blade and shaft mounting arrangement, comprising:
 a fan blade, said fan blade comprising a center tube and a plurality of blades arranged around said center tube;   a fan shaft inserted through said center tube; and   a locating member, said locating member comprising a torsionable portion sleeved onto said fan shaft and a positioning portion fastened to said fan blade;   wherein when said fan shaft is rotated, said torsionable portion of said locating member is twisted and firmly secured to said fan shaft so that said fan blade is rotated with said fan shaft.   
   
   
       2 . The fan blade and shaft mounting arrangement as claimed in  claim 1 , wherein said blades of fan blade are overlapped with respect to one another. 
   
   
       3 . The fan blade and shaft mounting arrangement as claimed in  claim 1 , wherein said fan blade further comprises a hub and a receptacle formed integrally on the center of an outer surface of said hub in communication with the inside of said center tube; said center tube is formed integrally on the center of an inner surface of said hub in axial alignment with said receptacle; and said blades are formed integrally with the periphery of said hub. 
   
   
       4 . The fan blade and shaft mounting arrangement as claimed in  claim 1 , further comprising a housing and two bearing members mounted in said housing at different elevations to support said fan shaft therebetween. 
   
   
       5 . The fan blade and shaft mounting arrangement as claimed in  claim 4 , wherein said bearing members are made of ceramics. 
   
   
       6 . The fan blade and shaft mounting arrangement as claimed in  claim 4 , wherein said bearing members are made of a friction-resistant material. 
   
   
       7 . The fan blade and shaft mounting arrangement as claimed in  claim 4 , further comprising at least one spring means supported between said housing and at least one said bearing member to force said bearing members into connection with said fan shaft. 
   
   
       8 . The fan blade and shaft mounting arrangement as claimed in  claim 4 , wherein said housing comprises two sockets that accommodate said bearing members respectively. 
   
   
       9 . The fan blade and shaft mounting arrangement as claimed in  claim 1 , wherein said locating member is a torsion spring. 
   
   
       10 . The fan blade and shaft mounting arrangement as claimed in  claim 1 , wherein each said blade comprises a sloping segment and an extension segment extending vertically upwardly from one side of said sloping segment, the sloping segments of said blades being partially overlapped with respect to one another around said hub to keep the extension segments of said blades in parallel.