BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an exploded, isometric view of a heat dissipation apparatus according to a preferred embodiment of the present invention;
FIG. 2 is an assembled view of the heat dissipation apparatus of FIG. 1;
FIG. 3 is an explanatory view for explaining a flow direction of airflow generated by a heat-dissipating fan of the heat dissipation apparatus of FIG. 1; and
FIG. 4 is an explanatory view for explaining a flow direction of airflow generated by a heat-dissipating fan of a related heat dissipation apparatus.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1 and 2, a heat dissipation apparatus 10 according to a preferred embodiment of the present invention includes a fin assembly 11, and a heat-dissipating fan 12. The fin assembly 11 includes a plurality of fins 111 thermally connected with a heat-generating component (not shown) for absorbing heat therefrom. The heat-dissipating fan 12 is a centrifugal blower for providing airflow with a high pressure flowing through the fin assembly 11 to take away heat therefrom.
The heat-dissipating fan 12 includes a housing 121, a cover 122 attached to the housing 121 with an inner space (not labeled) formed therebetween, a stator (not shown) accommodated in the inner space, and a rotor 124 including a plurality of blades 123 rotatably disposed around the stator along a counterclockwise direction.
The cover 122 defines a through hole therein functioning as an air inlet 125 of the heat-dissipating fan 12. The housing 121 includes a flat base plate 126 perpendicular to a rotation axis A of the rotor 124, and a volute sidewall 127 perpendicularly surrounding the base plate 126. An air channel 128 (FIG. 3) is formed between the blades 123 and an inner surface of the sidewall 127. The sidewall 127 of the housing 121 defines an opening therein functioning as an air outlet 129 of the heat-dissipating fan 12. The fin assembly 11 is disposed at the air outlet 129 of the heat-dissipating fan 12.
The sidewall 127 of the housing 121 protrudes a triangle-shaped first tongue 130 at a position which is at a right side of the housing 121 as viewed from FIG. 3 and distant from the air outlet 129 and points towards the blades 123 of the rotor 124. The first tongue 130 includes a first arcuate surface 137 being a portion of the inner surface of the sidewall 127, and a second arcuate surface 136 extending from an end of the first arcuate surface 137 towards a position apart from the blades 123 of the rotor 124. A distance between the first arcuate surface 137 of the first tongue 130 and free ends of the blades 123 gradually increases along the rotation direction of the rotor 124. A joint of the first and second arcuate surfaces 137, 136 is disposed closest to the free ends of the blades 123 than the other portions of the first arcuate surface 137 to thereby increase air pressure of the airflow.
Also referring to FIG. 3, the base plate 126 of the housing 121 projects a second tongue 131 upwardly and between the first tongue 130 and the air outlet 129. The second tongue 131 is located in the housing 121 and separates the inner space of the housing 121 into a main chamber (not labeled) between the second tongue 131 and a left side of the sidewall 127 and a sub-channel 134 between the second tongue 131 and a right side of the sidewall 127. An end of the second tongue 131 spaces a distance from the first tongue 130 to thereby form an entrance 133 for the sub-channel 134. The second arcuate surface 136 of the first tongue 130 guides the airflow entering into the sub-channel 134 via the entrance 133 to decrease the air resistance of airflow. An opposite end 132 of the second tongue 131 is bent toward the air outlet 129 of the heat-dissipating fan 12 and substantially parallels to the fins 111 of the fin assembly 11. A bulge 135 is formed at the bending area of the second tongue 131, which is closest to the free ends of the blades 123 than the other portions of the second tongue, to thereby increase the air pressure. A distance between a left side surface of the second tongue 131 and the free ends of the blades 123 gradually increases from the air outlet 129 towards the first tongue 130 as viewed from FIG. 3, whilst a distance between an opposite right side surface of the second tongue 131 and the sidewall 127 of the housing 121 gradually decreases from the bulge 135 towards the first tongue 130. That is, a width of the sub-channel 134 gradually increases from the first tongue 130 towards the bulge 135 of the second tongue 131.
The fins 111 of the fin assembly 11 are stacked together along a direction perpendicular to the rotation axis A of the rotor 124. Each of the fins 111 has a main body extending in a direction which is perpendicular to the direction along which the fins 111 are stacked. A plurality of air passages 112 are formed between two adjacent fins 111. The fin assembly 11 includes a left portion 113, a right portion 115, and a middle portion 114 located between the left and right portions 113, 115.
Particularly referring to FIG. 3, in operation of the heat-dissipating fan 12, the airflow generated by the rotation of the blades 123 flows through the bulge 135 of the second tongue 131 with its pressure being increased. The second tongue 131 guides the airflow to flow towards the first tongue 130. When the airflow leaves the second tongue 131, one part of the airflow enters into the sub-channel 134 via the entrance 133 and is guided toward right portion 115 of the fin assembly 11 along a direction substantially parallel to the fins 111 thereat. The other part of the airflow arrives at the joint of the first and second arcuate surfaces 137, 136 of the first tongue 130 with its pressure being further increased. The first arcuate surface 137 of the first tongue 130 and the sidewall 127 guides the other part of the airflow flowing through the air channel 128 towards the air outlet 129 of the heat-dissipating fan 12. When the airflow reaches the air outlet 129, one portion of the other part of the airflow flows towards the left portion 113 of the fin assembly 11 along a direction substantially parallel to the fins 111 thereat, whilst another portion of the other part of the airflow flows towards the middle portion 114 of the fin assembly 11 with acute angles formed between the flow direction of the airflow and the fins 111 of the middle portion 114 of the fin assembly 11. A division of the another portion of the other part of the airflow arrives at the second tongue 131 and is guided by the opposite end 132 of the second tongue 131 towards the middle portion 114 of the fin assembly 11 along a direction substantially parallel to the fins 111 thereat. Therefore, the airflow flowing towards the left, right, and middle portions 113, 115, 114 of the fin assembly 11 substantially parallels to the fins 111 thereof.
In the present invention, the airflow flowing towards the left, right, and middle portions 113, 115, 114 of the fin assembly 11 substantially parallels to the fins 111 thereof. A width of an area of the fin assembly 11 circled by the broken line of FIG. 3, shown the fins 111 forming the acute angles with the flow direction of the airflow, is narrower than a width of the area of the fin assembly 11 of the related heat dissipating apparatus 10. The airflow is therefore smoothly and evenly flowing through the air passages 112 of the fin assembly 11, which lowers the kinetic energy loss of the airflow when flowing through the fin assembly 11. The heat dissipating efficiency of the heat dissipation apparatus 10 is thus increased.
In the present invention, the heat-dissipating fan 12 includes two tongues, i.e. the first and second tongues 130, 131, with the second tongue 131 disposed at the air outlet 129 having an end 132 substantially parallel to the fins 111 of the fins assembly 111. Alternatively, the heat-dissipating fan may include more than two tongues, with at least one of the tongues disposed at the air outlet of the heat-dissipating fan having an end substantially parallel to the adjacent fins of the fins assembly. In addition, the second tongue 131 is disposed between the air outlet 129 and the first tongue 130. Alternatively, the more than two tongues may be arranged in other suitable manner.
It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
Patent Application
20080011461
