Heat sink provided with centrifugal fan

Abstract

The present invention is to provide a heat sink withheat pipe, which is limited in height, not so noisy, compact and highly efficient in radiation, and can lower the temperature inside a casing as a whole more effectively even when it is used in an electronic appliance limited in height such as a personal computer, a game machine or the like. A heat sink with centrifugal fan of the present invention, comprising: a cover of a given shape, which has an air intake and an air outlet; a heat receiving block, which is thermally connected to a heat generating body to be cooled; a heat conductive bottom, which is thermally connected at one surface to the heat receiving block, and is engaged with the cover to form a space; a radiation fin part, which is thermally connected to the bottom, has a given shape having at least an air inflow portion, and comprises a plurality of fin parts housed in the space; a centrifugal fan, which has a rotation axis positioned in a neighborhood of the air inflow portion of the radiation fin part, takes in air from the air intake, generates an air flow toward gap portions formed between adjacent fins of the radiation fin part, and generates an air flow along an inner wall of the cover toward the outlet; and heat transfer members, which are arranged such that resistance of the air flow generated toward a side of the radiation fin part becomes smaller, and are inserted through the plurality of fin parts to transfer heat from the bottom.

1 . A heat sink with centrifugal fan, comprising:
 a cover of a given shape, which has an air intake and an air outlet;   a heat receiving block, which is thermally connected to a heat generating body to be cooled;   a heat conductive bottom, which is thermally connected at one surface to the heat receiving block, and is engaged with the cover to form a space;   a radiation fin part, which is thermally connected to the bottom, has a given shape having at least an air inflow portion, and comprises a plurality of fin parts housed in the space;   a centrifugal fan, which has a rotation axis positioned in a neighborhood of the air inflow portion of the radiation fin part, takes in air from the air intake, generates an air flow toward gap portions formed between adjacent fins of the radiation fin part, and generates an air flow along an inner wall of the cover toward the outlet; and   heat transfer members, which are arranged such that resistance of the air flow generated by the centrifugal fan toward a side of the radiation fin part becomes smaller, and are inserted through the plurality of fin parts to transfer heat from the bottom.   
   
   
       2 . A heat sink with centrifugal fan of  claim 1 , wherein:
 the radiation fin part has a plurality of fin edge portions formed by a plurality of thin plate fins layered at prescribed intervals;   the plurality of fin edge portions has the air inflow portion of a semicircular shape opposed to at least the centrifugal fan, a curve portion connecting to the air inflow portion and extending along the inner wall of the cover, and an outlet portion opposed to the outlet.   
   
   
       3 . A heat sink with centrifugal fan of  claim 2 , wherein:
 a part of an outer peripheral surface of the centrifugal fan is opposed to the air inflow portion of the semicircular shape of the radiation fin part, and a remaining part of the outer peripheral surface is arranged to oppose the inner wall of the cover, so that the air flow along the inner wall of the cover is generated from a prescribed position of the inner wall of the cover as a start point toward the outlet.   
   
   
       4 . A heat sink with centrifugal fan of  claim 3 , wherein:
 the cover has an inflection part of a curve surface forming the inner wall of the cover at a position corresponding to a boundary portion between the air inflow portion and the curve portion of the radiation fin part; and   the inflection part causes the air flow along the inner wall of the cover.   
   
   
       5 . A heat sink with centrifugal fan of  claim 3 , wherein:
 the radiation fin part has another fin edge portion that is in direct contact with the inner wall of the cover; and   an end portion of another fin edge portion in question forms the start point.   
   
   
       6 . A heat sink with centrifugal fan of one of  claims 1 , wherein:
 the air outlet is in common with an outlet of the air passing through the radiation fin part and an outlet of the air flowing along the inner wall of the cover.   
   
   
       7 . A heat sink with centrifugal fan of  claim 1 , wherein:
 the heat transfer members are arranged in a radial pattern starting from the centrifugal fan.   
   
   
       8 . A heat sink with centrifugal fan of  claim 7 , wherein:
 the heat transfer members are arranged such that an air flow blown from the air inflow portion of the radiation fin part, flowing through the radiation fin part, to emerge from the curve portion, does not impede the air flowing along the inner wall toward the air outlet.   
   
   
       9 . A heat sink with centrifugal fan of  claim 8 , wherein:
 the heat transfer members are heat pipes.   
   
   
       10 . A heat sink with centrifugal fan of one of  claims 1 , wherein:
 the air outlet comprises an outlet for the air passing through the radiation fin part and an outlet for the air flowing along the inner wall of the cover, separately.   
   
   
       11 . A heat sink with centrifugal fan of one of  claims 1 , wherein:
 the heat receiving block is provided with at least one heat pipe.   
   
   
       12 . A heat sink with centrifugal fan of one of  claims 1 , wherein:
 the air outlet is provided being directed toward an outside of a casing.   
   
   
       13 . A radiation fin assembly, which receives, in a side of the assembly, a swirling air flow sent from a centrifugal fan, and performs cooling by the air flow, wherein:
 the radiation fin assembly comprises:   a plurality of radiation fins layered at intervals; and   a group of heat transfer members that are inserted through the layered radiation fins and transfers heat to the radiation fins;   the group of the heat transfer members includes a plurality of flat heat transfer members each having a cross section of a flat shape, and the plurality of flat heat transfer members are arranged to be distributed to a plurality of places of the radiation fins; and   the flat heat transfer members are distributed such that all or less flat heat transfer members are arranged in such a way that a longitudinal direction of the cross section of the flat shape is inclined with respect to a radius passing the cross section of the flat shape from a center of rotation of the centrifugal fan toward a same rotation direction as a rotation direction of the swirling air flow, to make an acute angle with the radius.   
   
   
       14 . A radiation fin assembly of  claim 13 , wherein:
 the flat heat transfer members each have a cross section of an ellipse.   
   
   
       15 . A heat sink with centrifugal fan, wherein:
 the heat sink with centrifugal fan comprises:   a centrifugal fan for sending a swirling air flow from a side of the centrifugal fan;   a radiation fin assembly that is positioned on the side of the centrifugal fan and used for cooling by the swirling air flow sent from the centrifugal fan;   a heat receiving block that is fixed to the radiation fin assembly, and transfers heat from a heat generating body to be cooled to the radiation fin assembly; and a case member that supports the centrifugal fan, the radiation fin assembly and the heat receiving block, and forms an air flow space;   the case member comprises:   first and second plate members for forming the air flow space by positioning the radiation fin assembly between the first and second plate members; and   a side member that covers a part of a side of a space between the first and second plate members, and cooperates with the first and second plate member to form the air flow space;   the radiation fin assembly comprises:   a plurality of radiation fins layered at intervals; and   a group of heat transfer members that are inserted through the layered radiation fins and transfers heat to the radiation fins;   the group of heat transfer members includes a plurality of flat heat transfer members each having a cross section of a flat shape, and the plurality of flat heat transfer members are arranged to be distributed to a plurality of places of the radiation fins; and   the flat heat transfer members are distributed such that all or less flat heat transfer members are arranged in such a way that a longitudinal direction of the cross section of the flat shape is inclined with respect to a radius passing the cross section of the flat shape from a center of rotation of the centrifugal fan toward a same rotation direction as a rotation direction of the swirling air flow, to make an acute angle with the radius.   
   
   
       16 . A heat sink with centrifugal fan of  claim 15 , wherein:
 the case member has an opening in some side of the case member; and   the radiation fin assembly is positioned such that a part of the radiation fin assembly faces to the opening, and another part is opposed to the side of the centrifugal fan.   
   
   
       17 . A heat sink with centrifugal fan of  claim 15 , wherein:
 the heat sink with centrifugal fan comprises a plurality of radiation fin assemblies and a plurality of heat receiving blocks fixed respectively to the radiation fin assemblies;   the plurality of radiation fin assemblies are positioned on the side of the centrifugal fan.   
   
   
       18 . A heat sink with centrifugal fan of  claim 16 , wherein:
 the heat sink with centrifugal fan comprises two radiation fin assemblies and two heat receiving blocks fixed respectively to the radiation fin assemblies;   the heat sink with centrifugal fan further comprises a third plate member in addition to the first plate member;   a pair of radiation fin assembly and heat receiving block is supported by the first plate member, and the other pair of radiation fin assembly and heat receiving block is supported by the third plate member; and   the plurality of radiation fin assemblies are positioned on the side of the centrifugal fan.   
   
   
       19 . A heat sink with centrifugal fan of  claim 18 , wherein:
 the third plate member is coupled with the first plate member, being displaceable in a direction of thickness of the third plate member.   
   
   
       20 . A heat sink with centrifugal fan of  claim 19 , wherein:
 the case member has a restriction mechanism that restricts a stroke of displacement in the direction of the thickness of the third plate.   
   
   
       21 . A heat sink with centrifugal fan of  claim 17 , wherein:
 the case member comprises at least one side having no opening and a plurality of sides having a plurality of openings collectively;   the plurality of radiation fin assemblies are arranged such that a part of a peripheral portion of each assembly faces to corresponding opening among the plurality of openings; and another part of the peripheral portion of each assembly is opposed to the side of the centrifugal fan.   
   
   
       22 . A heat sink with centrifugal fan of  claim 16 , wherein:
 the case member has a bypass that is formed along a side having no opening, between that side and a side of a radiation fin assembly adjacent to the side in question, to guide a part of the air flow to the opening.   
   
   
       23 . A heat sink with centrifugal fan of  claim 16 , wherein:
 the case member has a bypass that is formed along one side having no opening, between that side and a side of a radiation fin assembly adjacent to the side in question, to guide a part of the air flow to the opening; and   another side connecting to the one side functions as a guide wall for guiding a part of the swirling air flow from the centrifugal fan to the bypass.   
   
   
       24 . A heat sink with centrifugal fan of  claim 15 , wherein:
 the heat receiving block comprises a heat receiving portion that is thermally connected to a heat generating body to be cooled and a heat transfer portion for transferring heat of the heat receiving portion to the radiation fin assembly.   
   
   
       25 . A heat sink with centrifugal fan of  claim 15 , wherein:
 the flat heat transfer members each have a cross section of an ellipse.