Shaft structures of fan

Abstract

A shaft structure having a high service life is disclosed. An outer surface of the shaft is provided with a concave annular area and a plurality of first oil grooves. The first oil grooves extend helically along the outer surface; the fix end has a plurality of toothed portions disposed at interval and along the fixed end radially. A bearing is sleeved on the shaft and has an oil-keeping structure located on the outer surface. Thereby, lubricant can be remained on the surface of the shaft for reducing wear between the shaft and the bearing.

What is claimed is: 
     
         1 . Shaft structures of a fan for combining with a fan blade assembly, including:
 a shaft being a rod and having an outer surface, a fix end and a free end located opposite to the free end; the outer surface of the shaft being formed with a concave annular area and a plurality of first oil grooves, and the first oil grooves extend helically along the outer surface; the fix end embedded in the fan blade assembly and having a plurality of toothed portions, and the toothed portions disposed at interval along the fixed end radially; and   a bearing being a hollow cylinder, the bearing sleeved on the shaft, and the bearing having an outer surface and an oil-keeping structure located on the outer surface.   
     
     
         2 . The shaft structures of a fan according to  claim 1 , wherein the fan blade assembly includes a hub and a plurality of blades located at a periphery of the hub; the hub has an accommodating space and a slot, and the fix end is embedded in the slot. 
     
     
         3 . The shaft structures of a fan according to  claim 1 , wherein the fix end has an annular groove, and the annular groove is located at a side of the toothed portions and cut along the fix end radially. 
     
     
         4 . The shaft structures of a fan according to  claim 1 , wherein the first oil grooves are located at the concave annular area. 
     
     
         5 . The shaft structures of a fan according to  claim 1 , wherein the first oil grooves are extended from a middle of the concave annular area to the fix end and the free end. 
     
     
         6 . The shaft structures of a fan according to  claim 1 , wherein the fix end has an end face, and the toothed portions are provided on the end face. 
     
     
         7 . The shaft structures of a fan according to  claim 1 , wherein the oil-keeping structure includes a plurality of second oil grooves, and the second oil grooves are extend helically along an outer surface of the bearing. 
     
     
         8 . The shaft structures of a fan according to  claim 7 , wherein the second oil grooves are located at two sides of the bearing and extend helically in opposite directions. 
     
     
         9 . The shaft structures of a fan according to  claim 7 , wherein the oil-keeping structure further includes an oil slot, and the oil slot is located on an outer periphery of a middle section of the bearing. 
     
     
         10 . The shaft structures of a fan according to  claim 9 , wherein the oil slot is a semi-circular slot.