Thin cooling fan

Abstract

A thin cooling fan includes a fan shell, a motor, a plurality of blades, and a PCB. The fan shell comprises a base plate and a shell cover which cover to each other to form an inner space. The base plate has a first surface facing toward the inner space and a second surface having a receiving space and opposite to the first surface. The motor is combined in the inner space. The blades are disposed in the inner space and rotated by the motor. The PCB is disposed in the receiving space and flush with the second surface. Thus, the whole thickness of the cooling fan is reduced and the flow channel design in the inner space is not affected.

What is claimed is: 
     
         1 . A thin cooling fan, comprising:
 a fan shell comprising a base plate and a shell cover, wherein the base plate and the shell cover cover to each other to form an inner space and an air channel, wherein the base plate has a first surface facing toward the inner space and a second surface opposite to the first surface, wherein the second surface has a receiving space comprising a recess zone and a hollow zone, wherein the shell cover extends along the air channel to form a curved surface recessed toward the inner space;   a motor installed in the inner space;   a plurality of blades disposed in the inner space and driven by the motor to rotate; and   a printed circuit board (PCB) disposed in the receiving space and flush with the second surface.   
     
     
         2 . The thin cooling fan according to  claim 1 , wherein the air channel has an outlet, a first pressurization zone, and a second pressurization zone communicating with the first pressurization zone, wherein the first and the second pressurization zones are disposed at both sides of the outlet, wherein the air channel has a channel width, wherein the channel width of the first pressurization zone is less than that of the second pressurization zone. 
     
     
         3 . The thin cooling fan according to  claim 2 , wherein the curved surface is disposed in the second pressurization zone. 
     
     
         4 . The thin cooling fan according to  claim 2 , wherein the shell cover is provided with an opening in which the blades are protruded and exposed, wherein the air channel is disposed at the outer edge of the opening. 
     
     
         5 . The thin cooling fan according to  claim 4 , wherein the shell cover has a frame edge, wherein the second pressurization zone has a pressurization start and a pressurization end disposed on the frame edge, wherein an angle is defined by the vertex of an opening center, the line segment from the opening center to the pressurization start, and the line segment from the opening center to the pressurization end, wherein the angle is between 0 and 140 degrees. 
     
     
         6 . The thin cooling fan according to  claim 5 , wherein the angle is 125 degrees. 
     
     
         7 . The thin cooling fan according to  claim 4 , wherein the line defined by the pressurization start and the opening center passes through the outlet. 
     
     
         8 . The thin cooling fan according to  claim 4 , wherein the air channel is disposed at the outer edge of the inner space, wherein a flow cross section is defined by cutting the air channel along a profile line passing through an opening center, wherein the curved surface has a curved cross section along the profile line, wherein the ratio of the curved cross section to the flow cross section ranges from 1% to 5%. 
     
     
         9 . The thin cooling fan according to  claim 8 , wherein the ratio of the curved cross section to the flow cross section is 3%. 
     
     
         10 . The thin cooling fan according to  claim 2 , wherein the shell cover further comprises at least one guiding slot and at least one auxiliary inlet disposed in the at least one guiding slot, wherein the at least one guiding slot slopes from the surface of the shell cover toward the at least one auxiliary inlet which communicates with the air channel. 
     
     
         11 . The thin cooling fan according to  claim 9 , wherein the at least one guiding slot and the at least one auxiliary inlet are adjacent to the outlet. 
     
     
         12 . The thin cooling fan according to  claim 10 , wherein the at least one guiding slot and the at least one auxiliary inlet are adjacent to the curved surface. 
     
     
         13 . The thin cooling fan according to  claim 10 , wherein the at least one guiding slot and the at least one auxiliary inlet are plural in number, wherein the guiding slots and the auxiliary inlets are disposed correspondingly along the air channel. 
     
     
         14 . The thin cooling fan according to  claim 1 , wherein the recess zone comprises a first recess portion and a second recess portion, wherein the hollow zone comprises a first hollow portion and a second hollow portion, wherein the receiving space comprises a first receiving space and a second receiving space, wherein the first recess portion and the first hollow portion together form the first receiving space, wherein the second recess portion and the second hollow portion together form the second receiving space. 
     
     
         15 . The thin cooling fan according to  claim 14 , wherein the printed circuit board has a first substrate, a first solder point disposed on the first substrate, a second substrate, and a second solder point disposed on the second substrate, wherein the first substrate is attached to the first recess portion and the first solder point is correspondingly disposed in the first hollow portion, wherein the second substrate is attached to the second recess portion and the second solder point is disposed in the second hollow portion. 
     
     
         16 . The thin cooling fan according to  claim 14 , wherein the second receiving space is disposed on the outside of the blades. 
     
     
         17 . The thin cooling fan according to  claim 14 , wherein the blades are spaced in a radial direction and the second receiving space is disposed on the outside of the ends of the blades in the radial direction.