Fan structure

Abstract

A fan structure includes a cap, a fixing shaft, a bearing, an impeller and a protection lid, wherein the cap comprises a bottom portion, a body and an accommodating space. The fixing shaft is disposed within the accommodating space, a first end portion of the fixing shaft couples the bottom portion, and a second end portion of the fixing shaft protrudes to the body. The bearing couples to the fixing shaft, the second end portion of the fixing shaft protrudes to the bearing, and a hub of the impeller couples to the bearing. The second end portion of the fixing shaft protrudes to the hub. The protection lid couples to the second end portion of the fixing shaft to prevent lubricants for lubricating the bearing from splashing. The protection lid provides the impeller with protection to prevent the impeller from being compressed by external force to avoid destruction.

What is claimed is: 
     
         1 . A fan structure including:
 a cap having a bottom portion, a body and an accommodating space;   a fixing shaft disposed within the accommodating space, the fixing shaft comprises a first end portion coupled to the bottom portion, a second end portion protruded to the body and a middle portion located between the first end portion and the second end portion;   a bearing disposed within the accommodating space, the bearing comprises an axial hole coupled to the middle portion of the fixing shaft, and the second end portion of the fixing shaft protrudes to the bearing;   an impeller having a hub coupled to the bearing and a penetration hole formed at the hub, wherein the second end portion of the fixing shaft passes through the penetration hole and protrudes to the hub; and   a protection lid coupled to the second end portion of the fixing shaft, the protection lid and the hub are spaced apart from each other by an interval.   
     
     
         2 . The fan structure in accordance with  claim 1 , wherein the hub comprises a top surface and a slot recessed from the top surface, the protection lid comprises a ring wall accommodated within the slot, and the ring wall is spaced apart from the slot to define a restriction passage. 
     
     
         3 . The fan structure in accordance with  claim 1 , wherein the hub comprises a top surface, a slot recessed from the top surface and a blocking wall disposed at the slot, the protection lid comprises a ring wall accommodated within the slot, the blocking wall is located between the fixing shaft and the ring wall, and the blocking wall is spaced apart from the protection lid to define a blocking passage. 
     
     
         4 . The fan structure in accordance with  claim 3 , wherein the blocking wall comprises a height, the slot comprises a depth, and the height is not smaller than the depth. 
     
     
         5 . The fan structure in accordance with  claim 1 , wherein the penetration hole comprises a ring surface, the ring surface can be an inclined ring surface. 
     
     
         6 . The fan structure in accordance with  claim 5 , wherein the ring surface faces toward the second end portion of the fixing shaft. 
     
     
         7 . The fan structure in accordance with  claim 1 , wherein the protection lid comprises a coupling base having an inclined surface, the second end portion of the fixing shaft is coupled to the coupling base, and the inclined surface faces toward the bearing. 
     
     
         8 . The fan structure in accordance with  claim 1 , wherein the hub comprises a combining portion located within the accommodating space of the cap, and the combining portion of the hub is coupled to the bearing. 
     
     
         9 . The fan structure in accordance with  claim 2 , wherein a stirring layer is formed on a first surface of the slot. 
     
     
         10 . The fan structure in accordance with  claim 3 , wherein a stirring layer is formed on a second surface of the blocking wall. 
     
     
         11 . The fan structure in accordance with  claim 1 , wherein a stirring layer is formed on an inner surface of the protection lid. 
     
     
         12 . A fan structure including:
 a fixing shaft having a first end portion and a second end portion;   an impeller having a hub and a penetration hole formed at the hub, wherein the second end portion of the fixing shaft passes through the penetration hole and protrudes to the hub; and   a protection lid coupled to the second end portion of the fixing shaft, the protection lid and the hub are spaced apart by an interval.   
     
     
         13 . The fan structure in accordance with  claim 12 , wherein the hub comprises a top surface and a slot recessed from the top surface, the protection lid comprises a ring wall accommodated within the slot, and the ring wall is spaced apart from the slot to define a restriction passage. 
     
     
         14 . The fan structure in accordance with  claim 12 , wherein the hub comprises a top surface, a slot recessed from the top surface and a blocking wall disposed at the slot, the protection lid comprises a ring wall accommodated within the slot, the blocking wall is located between the fixing shaft and the ring wall, and the blocking wall is spaced apart from the protection lid to define a blocking passage. 
     
     
         15 . The fan structure in accordance with  claim 14 , wherein the blocking wall comprises a height, the slot comprises a depth, and the height is not smaller than the depth. 
     
     
         16 . The fan structure in accordance with  claim 13 , wherein a stirring layer is formed on a first surface of the slot. 
     
     
         17 . The fan structure in accordance with  claim 14 , wherein a stirring layer is formed on a second surface of the blocking wall. 
     
     
         18 . The fan structure in accordance with  claim 12 , wherein a stirring layer is formed on an inner surface of the protection lid.