Centrifugal heat dissipation fan

Abstract

A centrifugal heat dissipation fan including a housing and an impeller is provided. The housing has at least one inlet and at least one outlet. The impeller is disposed in the housing and rotates about an axis. The inlet is located in an axial direction of the axis and corresponds to the impeller. The outlet is located in a radial direction relative to the axis. The inlet is divided into a compression section and a release section in the rotation direction of the impeller, and the compression section has a uniform first radial dimension relative to the axis. The release section has an extended second radial dimension relative to the axis, and the second radial dimension is greater than the first radial dimension.

What is claimed is: 
     
         1 . A centrifugal heat dissipation fan, comprising:
 a housing, having at least one inlet and at least one outlet; and   an impeller, disposed in the housing, rotating about an axis, the at least one inlet located in an axial direction of the axis and corresponding to the impeller, the at least one outlet located in an radial direction relative to the axis, the at least one inlet divided into a compression section and a release section in a rotation direction of the impeller, wherein the compression section has a uniform first radial dimension relative to the axis, the release section has an extended second radial dimension relative to the axis, and the second radial dimension is greater than the first radial dimension.   
     
     
         2 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the impeller rotates and causes a working fluid to flow into the housing through the at least one inlet and flow out of the housing though the at least one outlet, and a flow velocity of the working fluid in the housing reaches a maximum value at the release section. 
     
     
         3 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the impeller rotates and causes a working fluid to flow into the housing through the at least one inlet and flow out of the housing though the at least one outlet, the second radial dimension gradually extends from the first radial dimension to a maximum value and then gradually reduces to the first radial dimension, and a location where the second radial dimension reaches the maximum value is a location where the flow velocity of the working fluid reaches a maximum value. 
     
     
         4 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the release section has a toothed shape. 
     
     
         5 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the second radial dimension is uniform. 
     
     
         6 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the second radial dimension is 1.2 to 1.5 times greater than the first radial dimension. 
     
     
         7 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein blades of the impeller have a third radial dimension relative to the axis, and the first radial dimension is 70% to 85% of the third radial dimension. 
     
     
         8 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the impeller rotates and causes a working fluid to flow into the housing through the at least one inlet and flow out of the housing though the at least one outlet, and at least portions of the release section expose ends of the blades when the blades of the impeller pass through the release section, so that a portion of the working fluid flowing into the housing from the at least portions is not in contact with the blades of the impeller. 
     
     
         9 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the housing has a tongue portion, the tongue portion corresponds to a starting point of the compression section in the rotation direction of the impeller, and a central angle provided between the starting point of the compression section and an end point of the compression section relative to the axis is 175 degrees to 215 degrees. 
     
     
         10 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the housing has a tongue portion, the tongue portion corresponds to a starting point of the compression section in the rotation direction of the impeller, a starting point of the release section is an end point of the compression section, and a central angle provided between the starting point of the release section and an end point of the release section relative to the axis is 40 degrees to 130 degrees. 
     
     
         11 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein a starting point of the release section is a position obtained through rotation by +/−20 degrees about the axis relative to a radial direction of the axis, and the radial direction is parallel to a plane where the at least one outlet is located. 
     
     
         12 . The centrifugal heat dissipation fan as claimed in  claim 1 , wherein the housing has a first outlet and a second outlet, the release section is divided into a first sub section and a second sub section, the first sub section corresponds to the first outlet, the second sub section corresponds to the second outlet, and the first sub section is connected between the compression section and the second sub section in the rotation direction of the impeller. 
     
     
         13 . The centrifugal heat dissipation fan as claimed in  claim 12 , wherein a flow velocity of the working fluid in the housing reaches a maximum value respectively at the first sub section and the second sub section. 
     
     
         14 . The centrifugal heat dissipation fan as claimed in  claim 12 , wherein the impeller rotates and causes a working fluid to flow into the housing through the at least one inlet and flow out of the housing though the at least one outlet, the second radial dimension gradually extends from the first radial dimension to reach the first sub section and gradually reduces to the first radial dimension from the second sub section, and a flow velocity of the working fluid reaches a maximum value respectively at the first sub section and the second sub section. 
     
     
         15 . The centrifugal heat dissipation fan as claimed in  claim 12 , wherein the release section has a plurality of radial depressions, and blades of the impeller are exposed when passing through each of the radial depressions. 
     
     
         16 . The centrifugal heat dissipation fan as claimed in  claim 12 , wherein the housing has a tongue portion, the tongue portion corresponds to a starting point of the compression section in the rotation direction of the impeller, and a central angle provided between the starting point of the compression section and an end point of the compression section relative to the axis is 85 degrees to 125 degrees. 
     
     
         17 . The centrifugal heat dissipation fan as claimed in  claim 12 , wherein the housing has a tongue portion, the tongue portion corresponds to a starting point of the compression section in the rotation direction of the impeller, a starting point of the release section is an end point of the compression section, and a central angle provided between the starting point of the release section and an end point of the release section relative to the axis is 40 degrees to 220 degrees. 
     
     
         18 . The centrifugal heat dissipation fan as claimed in  claim 12 , wherein a starting point of the release section is a position obtained through rotation by +/−20 degrees about the axis relative to a radial direction of the axis, and the radial direction is parallel to a plane where the at least one outlet is located.