JP2010129584A - Working device for heat sink and working method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve heat radiation efficiency of a heat sink by a simple method. <P>SOLUTION: A working device 100 is for a heat sink 20 including a substrate 21 and a metal solid fin 22 protruding from the substrate 21. It includes a stage 31 which holds a surface on the side opposite to the surface where the fin 22 of the substrate 21 is formed, and a press die 40 which presses a part of thickness of the fin 22 toward the substrate 21 so that a part of thickness of the fin 22 is deformed into a projection 23 which crosses the length direction of the fin 22 on the surface of substrate 21 at the root of the fin 22. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a heat sink processing apparatus and method for cooling a semiconductor element.

  In recent years, hybrid vehicles using a combination of two types of drive sources, that is, an engine and a motor generator, as a vehicle drive source, and electric vehicles that drive a vehicle with a motor generator have been increasingly used. In such an electric vehicle, a chargeable / dischargeable secondary battery and the DC power of the secondary battery are converted into three-phase AC power for driving the motor generator and output, and the AC power regenerated by the motor generator is secondary An inverter that is a power converter for charging the battery is mounted. The inverter performs power conversion by the switching operation of the switching element, but generates large heat during the switching operation. In addition to an inverter, an electric vehicle may be equipped with a boost converter or a DC / DC converter that converts a DC voltage. These converters also use switching elements that generate a large amount of heat during operation. . As the switching element, a power transistor is often used. For example, an insulated gate bipolar transistor (IGBT) or the like is used.

  In an electrical apparatus such as an inverter using such a highly exothermic semiconductor element, a cooling device is attached in order to remove heat generated in the semiconductor element and bring the semiconductor element to an appropriate operating temperature. For example, Patent Literature 1 includes a first member provided with a plurality of straight fins and a flat plate-like second member combined with the first member, and a flow between the fins of the first member and the second member. The present invention relates to a cooling structure for a semiconductor element that cools a semiconductor element attached to a surface opposite to a fin of a first member by flowing cooling water through a path, and includes fins between the semiconductor elements along a flow direction of a cooling fluid. Proposals have been made to increase the cooling efficiency by forming protrusions between them or by forming protrusions on the cooling flow path side of the second member to which the semiconductor element is not attached, thereby causing disturbance in the flow of the flow path. .

  Patent Document 2 proposes a method for improving heat exchange efficiency by forming a triangular plate cut and raised on a heat dissipating fin and generating turbulence in the air flowing through the cooling flow path. ing.

  Patent Document 3 discloses a method of manufacturing a cooling fin that is processed into a press corrugated plate and then pressed into irregularities in a direction perpendicular to the direction in which the fins of the pressed fins extend to form offset fins. Proposed.

JP 2008-172014 A JP-A-8-271169 JP 2006-136905 A

  As described in FIG. 5 of Patent Document 1, when a projection is formed by pressing on the side of the plate on which the switching element is arranged, the half-cut dowel is actually processed from the side on which the switching element is mounted. And a method of projecting the protrusion toward the refrigerant flow path side is used. However, when the projections are processed by this method, the surface on the side where the switching element is arranged becomes dented, and the heat conduction between the switching element and the heat sink deteriorates at that portion, so that the refrigerant flow path Even if the protrusion is provided, the cooling efficiency is lowered.

  Since the size of the switching element used in an electric vehicle or the like varies depending on its capacity, there is no dent after processing the protrusion in the region where the switching element is arranged, and if the protrusion is arranged between the switching elements, the heat sink In accordance with the size of each switching element, for example, it is necessary to have a different design for each vehicle type, which increases the number of parts and increases the cost.

  Further, the shape of the fin as described in Patent Document 2 or Patent Document 3 requires a large number of processing steps and is difficult to apply to a mass-produced product such as a heat sink of an electric vehicle. There is.

  An object of this invention is to improve the thermal radiation efficiency of a heat sink by a simple method.

  The heat sink processing apparatus of the present invention is a heat sink processing apparatus including a substrate and metal solid fins protruding from the substrate, and holds a surface opposite to the surface on which the fins of the substrate are formed. A stage, and a press die that presses a part of the fin thickness toward the substrate and deforms a part of the fin thickness into a protrusion that intersects the longitudinal direction of the fin on the base plate surface of the fin. It is characterized by that.

  Further, in the heat sink processing apparatus of the present invention, the fin is a plurality of straight fins, and the press die is preferably pressed at least one fin, and the width of the processing portion of the press die is It is also preferable to simultaneously press the opposing portions of the opposing fins that are larger than the distance between the fins.

  In the heat sink processing apparatus of the present invention, the press die is provided on the base, a first guide rib provided on the base and fitted in a groove between the press side surface of the fin to be pressed and the fin facing the press die. A second guide rib provided in a groove between the fin opposite to the surface opposite to the press side surface of the fin to be pressed, and provided on a side surface of the first guide rib, toward the second guide rib A protruding projecting protrusion, a notch extending in a direction intersecting with the extending direction of the first guide rib, provided in the region where the processed protrusion of the first guide rib is provided toward the base from the tip of the first guide rib; The press die includes two second guide ribs and a first guide rib provided between the second guide ribs, and the first guide rib is processed. Causing it projecting toward the first respective second guide rib from both sides of the guide rib, also suitable as.

  The heat sink processing method of the present invention is a heat sink processing method including a substrate and metal solid fins protruding from the substrate, and is opposite to the surface on which the fins of the substrate are formed on the stage. Holding the surface, pressing a part of the thickness of the fin toward the substrate, and deforming a part of the thickness of the fin into a protrusion intersecting with the longitudinal direction of the fin on the substrate surface at the base of the fin. And

In the heat sink processing method of the present invention, the fin is a plurality of straight fins,
The press die is also suitable for pressing at least one fin, and the width of the processed portion of the press die is larger than the distance between the surfaces of the fins, and the opposing portions of the opposing fins are simultaneously pressed. This is also suitable.

  The present invention has an effect that the heat dissipation efficiency of the heat sink can be improved by a simple method.

  Preferred embodiments of the present invention will be described below with reference to the drawings. Before describing an embodiment of a heat sink processing apparatus, a semiconductor element cooler 10 incorporating fins processed by the heat sink processing apparatus of the present embodiment will be described with reference to FIGS. 1 and 2.

As shown in FIG. 1, the cooler 10 includes a bottom plate 11, an end plate 12, a top plate 13, a ceramic substrate 14 attached to the surface of the top plate 13, and a semiconductor element 15 attached to the surface, and a top plate 13. And a heat sink 20 attached to a surface opposite to the surface on which the semiconductor element 15 is attached. As shown in FIG. 2, the heat sink 20 has a substrate 21 and straight fins 22 formed integrally by drawing aluminum. The fin 22 is solid, the thickness of the fin 22 is T _f , the height of the fin 22 is H _f , and the width of the groove 25 between the fins 22 is W _f .

  The bottom plate 11, the end plate 12, and the top plate 13 are assembled into a sealed structure by brazing, and a coolant for cooling the semiconductor element 15 flows inside. The straight fins 22 form a refrigerant flow path, and the refrigerant flows through the grooves 25 between the fins 22 to absorb the heat of the semiconductor element 15 through the substrate 21, the top plate 13, and the ceramic substrate 14, thereby cooling the semiconductor element 15. To do.

  A protrusion 23 that protrudes from the surface of the substrate 21 toward the tip of the fin 22 is formed at the base portion of the fin 22, which disturbs the refrigerant flowing in the groove 25 between the fins 22, thereby improving the heat dissipation efficiency of the heat sink 20. It is configured so that it can be increased. Further, a recess 24 formed when the protrusion 23 is formed is formed on the side surface of the fin 22 where the protrusion 23 is formed. This is because, when the fin 22 is processed, the fin 22 is pressed and crushed to move the metal of the portion toward the substrate 21 to form the projection 23, so that the crushed portion of the fin 22 is This is because the recess 24 remains.

  Next, an embodiment of the heat sink processing apparatus 100 of the present embodiment will be described with reference to FIGS. 3 and 4. As shown in FIG. 3, the heat sink processing apparatus 100 of the present embodiment includes a stage 31 that holds the heat sink 20 and a press die 40 that presses the fins 22.

  The stage 31 is a flat plate that holds a plane opposite to the side on which the fins 22 of the heat sink 20 are formed, and includes a suction device, a fixing device, and the like for fixing the substrate 21 of the heat sink 20. Yes.

  As shown in FIGS. 3 and 4, the press die 40 is formed of a high-strength steel material such as tool steel, and is provided on the base 41 and the base 41 and fits into the groove 25 of the fin 22 of the heat sink 20. A rectangular parallelepiped first guide rib 42 and a second guide rib 43 are provided. Each processing projection 44 protruding toward each second guide rib 43 is provided on both side surfaces of the first guide rib 42. A notch 45 extending in a direction perpendicular to the direction in which the first guide rib 42 extends is provided in a portion of the first guide rib 42 where the processing protrusion 44 is provided. The notch 45 has a square groove shape.

The width W ₁ of the first guide rib 42 and the second guide rib 43 is substantially equal to or slightly narrower than the width W _f of the groove 25 between the fins 22, and each rib 42, 43 is smoothly between the fins 22. It is comprised so that it can fit in the groove | channel 25 of this. Further, the gap W ₂ between the first guide rib 42 and the second guide rib 43 is substantially equal to or slightly wider than the thickness T _f of the fin 22 of the heat sink 20. The projecting height H ₁ of the first guide rib 42 and the second guide rib 43 from the base 41 is configured to be higher than the height H _f of the fins 22 of the heat sink 20. The processing protrusions 44 formed on the first guide rib 42 have a rectangular parallelepiped shape and are formed integrally with the base 41. The protrusion amount D of the processing projection 44 in the direction toward the second guide rib 43 is approximately ½ of the thickness _Tf of the fin 22 of the heat sink 20. The height H ₂ of the notches 45, as the length direction of the length of the first guide ribs 42 of the working protrusions 44 lacks 45 off L, and the volume = D × fin 22 is processed projection 44 pushes (H _f− H ₂ ) × L, and the volume of the notch 45 = H ₂ × W _f × L is the same as D × (H _f −H ₂ ) = H ₂ × W _f . It is the height to meet. In the present embodiment, it has been described that the press die 40 is made of a steel material having high strength. However, as long as aluminum can be pressed, the press die 40 is not limited to metal, and may be formed of, for example, ceramics.

  A process of processing the fins 22 of the heat sink 20 by the heat sink processing apparatus 100 configured as described above will be described. As shown in FIG. 3, the substrate 21 of the heat sink 20 is fixed to the stage 31. Then, alignment is performed so that the first guide rib 42 and the second guide ribs 43 of the press die 40 are respectively aligned with the grooves 25 between the fins of the heat sink 20.

  When the alignment is completed, the press die 40 is pressed against the heat sink 20 by a pressure device (not shown). As shown in FIG. 5, when the press die 40 is pressed against the heat sink 20, the lower surface of the processing projection 44 of the press die 40 first hits the tip of the fin 22. When the press die 40 is pushed down, the hard processing projection 44 bites into the fin 22 from the tip of the aluminum fin 22, deforms the aluminum constituting the fin 22, and moves it to the base side of the fin 22. When the press die 40 is further pushed down, the lower surface of the machining projection 44 pushes down the aluminum moved to the base side of the fin 22, so that the aluminum enters the notch 45 provided in the first guide rib 42. Go. When the press die 40 is further pushed down, the aluminum that has entered the notch 45 is shaped into a quadrangle along the notch 45 and is formed into a protrusion 23 extending in a direction perpendicular to the groove 25 between the fins 22. When the press die 40 is further pushed down, the tips of the first and second guide ribs 42 and 43 come into contact with the bottom of the groove 25 between the fins 22, that is, the fin 22 side surface of the substrate 21, and the aluminum compression is stopped.

  As shown in FIG. 6, when the press die 40 is raised, the heat sink 20 is crushed by the pedestal-shaped protrusions 23 formed by deforming aluminum of the fins 22 by pressing and the processing protrusions 44 of the press die 40. Thus, a recess 24 that is recessed in the thickness direction of the fin 22 is formed. As shown in FIG. 7, since both the protrusions 23 and the recesses 24 are formed at right angles to the direction in which the grooves 25 that serve as the refrigerant flow paths extend, the effect of disturbing the flow of the refrigerant and improving the heat dissipation efficiency of the heat sink 20 is achieved. Play. Since the recess 24 is formed by pushing down the processing projection 44 of the press die 40, the recess 24 has a shape recessed in the shape of the processing projection 44. In this embodiment, since the processing projection 44 has a rectangular parallelepiped shape, the recess 24 has a square groove shape. Further, the shape of the protrusion 23 is a shape along the shape of the notch 45 of the press die 40. In the present embodiment, since the notch 45 has a square groove shape, the shape of the protrusion is a rectangular parallelepiped shape. The shape of the protrusion 23 can also be changed by changing the shape of the notch 45. For example, when the notch 45 has a triangular groove shape, a triangular prism-shaped protrusion 23 is formed.

  As shown in FIG. 8, the above procedure is repeated, or the fin 22 is pressed from the front end side of the fin 22 toward the substrate 21 using a press die 40 provided with a plurality of processing projections 44. The plurality of protrusions 23 can be formed in the groove 25 of the heat sink 20. As shown in FIG. 8, the plurality of protrusions 23 may be formed in a staggered manner in each groove 25, or may be provided only in some flow paths.

  Since the processing apparatus for the heat sink 20 according to the present embodiment described above forms the protrusions 23 by crushing the fins 22 from the front end side of the fins 22 of the heat sink 20 toward the substrate 21, the fins of the substrate 21 of the heat sink 20 are formed. The projection 23 can be provided at an arbitrary position without impairing the flatness on the opposite side to 22, and the heat dissipation effect of the heat sink 20 can be enhanced.

  In the present embodiment, the press die 40 has been described as having the processing protrusions 44 provided on both side surfaces of the first guide rib 42, but it may be provided only on one side surface without being provided on both sides. In this case, the second guide rib 43 may be provided only on the side of the first guide rib 42 on which the processing projection 44 is provided, so that the compact press die 40 may be used.

It is sectional drawing which shows the cooler of a semiconductor element. It is the top view and sectional drawing which show a heat sink. It is explanatory drawing which shows the processing apparatus of the heat sink of this invention. It is a perspective view which shows the press die in the processing apparatus of the heat sink of this invention. It is explanatory drawing which shows the process process of the fin in the processing apparatus of the heat sink of this invention. It is the top view and sectional drawing which show the fin and protrusion which were processed with the processing apparatus of the heat sink of this invention. It is a perspective view which shows the fin and protrusion which were processed with the processing apparatus of the heat sink of this invention. It is a top view which shows the heat sink processed with the processing apparatus of the heat sink of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Cooler, 11 Bottom plate, 12 End plate, 13 Top plate, 14 Ceramic substrate, 15 Semiconductor element, 20 Heat sink, 21 Substrate, 22 Fin, 23 Projection, 24 Depression, 25 Groove, 31 Stage, 40 Press mold, 41 Base , 42 1st guide rib, 43 2nd guide rib, 44 process protrusion, 45 notch, 100 heat sink processing apparatus.

Claims (8)

A heat sink processing apparatus including a substrate and a metal solid fin protruding from the substrate,
A stage for holding a surface opposite to the surface on which the fins of the substrate are formed;
A press die that presses a portion of the fin thickness toward the substrate and deforms a portion of the fin thickness into a protrusion that intersects the longitudinal direction of the fin on the base substrate surface of the fin;
An apparatus for processing a heat sink. The processing apparatus according to claim 1,
The fin is a plurality of straight fins,
The press mold is to press at least one fin,
A processing device characterized by The processing apparatus according to claim 2,
The width of the processing part of the press die is larger than the inter-surface distance between the fins, and simultaneously pressing the opposing parts of the opposing fins,
A processing device characterized by It is a processing device given in any 1 paragraph of Claims 1-3,
Press mold is
Base and
A first guide rib which is provided in the base and fits into a groove between the press side surface of the fin to be pressed and the fin facing the fin;
A second guide rib which is provided in the base and fits into a groove between the press side of the fin to be pressed and the surface opposite to the press side;
A processing projection provided on a side surface of the first guide rib and projecting toward the second guide rib;
A notch that extends from the tip of the first guide rib toward the base in the region where the processing projection of the first guide rib is provided, and extends in a direction intersecting with the direction in which the first guide rib extends;
A processing apparatus comprising: The processing apparatus according to claim 4,
The press die includes two second guide ribs and a first guide rib provided between the second guide ribs,
The processing protrusions of the first guide ribs protrude from both side surfaces of the first guide ribs toward the second guide ribs,
A processing device characterized by A heat sink processing method including a substrate and a metal solid fin protruding from the substrate,
Hold the surface opposite to the surface where the fins of the substrate are formed on the stage,
A part of the fin thickness is pressed toward the substrate, and a part of the fin thickness is deformed into a protrusion intersecting with the longitudinal direction of the fin on the base substrate surface of the fin;
A processing method of a heat sink characterized by the above. The processing method according to claim 6,
The fin is a plurality of straight fins,
The press mold is to press at least one fin,
A processing method characterized by The processing method according to claim 7,
The width of the processing part of the press die is larger than the inter-surface distance between the fins, and simultaneously pressing the opposing parts of the opposing fins,
A processing method characterized by

Images