JP2014183277A - Cooler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooler which improves cooling performance and achieves downsizing.SOLUTION: A cooler 2 includes: a base plate 3 where cooled objects are attached to a front surface 3a; multiple fins 4 which are attached to a rear surface 3b of the base plate 3 being aligned; and a refrigerant nozzle 5 which jets a refrigerant to the base plate 3 from the rear surface side. Slits 6 which reach the base plate 3 are provided at the respective fins 4 so as to be arranged in a line and traverse the multiple fins 4. Multiple through holes 41 are formed in each fin 4.

Description

  The present invention relates to a cooler. In particular, the present invention relates to a collision jet type cooler in which a cooling target such as a semiconductor chip is attached to one surface of a base plate, and a refrigerant collides with the back surface of the base plate.

  In order to cool a semiconductor chip or an electronic component, a cooler of a type in which a semiconductor chip or the like is attached to one surface and a refrigerant is allowed to flow on the back side may be used. In this specification, a part to which a cooling target such as a semiconductor chip is attached is referred to as a “base plate”. For convenience of explanation, the surface on which the object to be cooled is attached is referred to as the front surface of the base plate, and the opposite surface is referred to as the back surface. The back surface corresponds to the inner wall of the flow path through which the refrigerant flows.

  In order to increase the cooling efficiency, a cooler has been proposed in which the refrigerant is ejected toward the base plate instead of in parallel with the base plate. Such a type of cooler is sometimes referred to as an impinging jet type cooler. Patent Document 1 discloses a cooler of that type. In this technique, a plurality of fins are installed on the back surface of the base plate. The refrigerant nozzle is directed to the back side of the region where the object to be cooled is attached. The refrigerant sprayed on the base plate vigorously flows between the plurality of fins. Cooling of the cooling target is promoted by vigorously spraying the refrigerant onto the back side of the mounting region of the cooling target. Further, the refrigerant that has collided with the back surface of the base plate then flows along the fins, and cools the object to be cooled also by exchanging heat with the fins. In addition, a refrigerant discharge path is arranged so as to face the back surface of the base plate at the tip of the fin extending from the base plate. The refrigerant discharge path has a U-shaped cross section, and the U-shaped opening faces the fin and is disposed so as to extend in a direction perpendicular to the plane of the fin. Both sides of the refrigerant discharge path in the short direction correspond to the refrigerant ejection holes. That is, the refrigerant is ejected from both sides of the refrigerant discharge path toward the base plate. The refrigerant that has bounced off the base plate is discharged through a U-shaped refrigerant discharge passage.

JP 2011-166113 A

  In the cooler as described above, the refrigerant is continuously supplied into the cooler to cool the base plate and the fins, and the cooled refrigerant is continuously discharged to the outside through the refrigerant discharge path. Therefore, in order to discharge the continuously supplied refrigerant without stopping the flow, a refrigerant discharge passage having a certain size is formed to discharge the refrigerant. As a result, the cooler may be increased in size. In view of the above problems, the technology disclosed in this specification provides a cooler that can be downsized.

  The technology disclosed in the present specification relates to a cooler that cools a cooling target attached to a base plate. This cooler has a base plate to which a cooling target is attached on one side, a plurality of fins attached side by side on the other side opposite to the one side of the base plate, and a jet of refrigerant from the other side toward the base plate. And a refrigerant nozzle. In addition, a slit reaching each base plate is provided in a row so as to cross the plurality of fins. Each fin has a plurality of through holes penetrating in the direction in which the fins are arranged. The cooler preferably includes a refrigerant discharge port that discharges the refrigerant ejected from the refrigerant nozzle to the outside, and the refrigerant ejected from the refrigerant nozzle toward the base plate passes through the through holes in the fin alignment direction. It flows and is discharged to the outside from the refrigerant outlet. According to such a configuration, since the refrigerant ejected from the refrigerant nozzle flows through the through hole after cooling the base plate, the refrigerant can be sent to the refrigerant discharge port through the through hole, and the refrigerant can be discharged from the refrigerant discharge port. Can be discharged. Therefore, by flowing the refrigerant through the through hole, the space for discharging the refrigerant can be reduced, and the entire cooler can be reduced in size. In the cooler described above, it is preferable that the refrigerant nozzle is inserted into the slit.

The perspective view of the cooler of an embodiment is shown (the case is drawn with the imaginary line). An exploded perspective view of a cooler is shown (case is omitted). Sectional drawing along the III-III line | wire of FIG. 1 is shown. Sectional drawing along the IV-IV line of FIG. 3 is shown. A cross-sectional view of the cooler is shown. The figure explaining an example of the manufacturing method of the fin which has a through-hole is shown.

  The cooler of an embodiment is explained with reference to drawings. FIG. 1 is a perspective view of the cooler 2. However, in FIG. 1, the housing 10 is drawn with a virtual line (two-dot chain line) and the internal structure is drawn with a solid line so that the internal structure of the cooler 2 can be understood. FIG. 2 is an exploded perspective view of components (base plate 3, refrigerant nozzle 5, partition plate 7, etc.) excluding the housing. 3 is a cross-sectional view taken along line III-III in FIG. 1, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG.

  As shown in FIGS. 1 to 4, the cooler 2 includes a base plate 3 in which a mounting area to be cooled is defined on one surface, and a plurality of fins 4 arranged side by side on the other surface of the base plate 3, A partition plate 7 that divides a supply channel and a discharge channel of the coolant in the housing, a coolant nozzle 5 that ejects the coolant toward the base plate 3, and a housing 10 are configured. All members are made of a metal with high thermal conductivity, typically aluminum. For convenience of explanation, referring to the coordinate system depicted in the figure, the surface of the base plate 3 facing the negative Z-axis direction is referred to as the front surface 3a (one surface) and facing the positive Z-axis direction. The surface that is present is referred to as back surface 3b (the other surface). A cooling target attachment region is defined on the front surface 3a. A plurality of fins 4 are provided on the back surface 3b. The fin 4 is formed in a flat plate shape from a metal such as aluminum.

  The cooler 2 efficiently cools the cooling target attached to the cooling target attachment region by causing the refrigerant nozzle 5 to vigorously collide the refrigerant with the back surface 3b of the base plate 3. The object to be cooled is typically a semiconductor chip. The refrigerant is a liquid, typically water or antifreeze.

  The plurality of fins 4 are arranged in parallel to the back surface 3b of the base plate 3 so that the planes thereof face each other. Further, the plurality of fins 4 are fixed to the back surface 3b of the base plate 3 in an upright state, and are arranged at equal intervals along the Y-axis direction. As shown in FIG. 2, each fin is provided with a slit 6. The slits 6 of the plurality of fins 4 are provided in a straight line in the fin arrangement direction. In other words, the slits 6 are provided in a row so as to cross the plurality of fins 4 across the plurality of fins. Each slit 6 extends from the tip of the fin 4 to the base plate 3.

  As shown in FIGS. 1 and 2, the refrigerant nozzle 5 is fitted into the slit 6. The refrigerant nozzle 5 extends substantially perpendicular to the back surface 3 b of the base plate 3, and the tip opening faces the base plate 3. The tip of the refrigerant nozzle 5 passes through the slit 6 and reaches the vicinity of the base plate 3.

  Engagement protrusions 5 a are provided on both sides of the front end of the refrigerant nozzle 5 in the longitudinal direction, and on the other hand, engagement recesses 5 b are provided on the base plate 3 at positions corresponding to the engagement protrusions 5 a. When the refrigerant nozzle 5 is inserted into the slit 6, the engagement protrusion 5 a of the refrigerant nozzle 5 is fitted into the engagement recess 5 b of the base plate 3, and the tip of the refrigerant nozzle 5 is fixed to the base plate 3.

  The refrigerant nozzle 5 extends from the partition plate 7. The partition plate 7 is a plate that bisects the internal space of the housing 10, and the space above the partition plate 7 constitutes the refrigerant supply channel A (refrigerant supply path), and the space below the partition plate 7 (partition plate 7 And the space between the fins 4) constitute a refrigerant discharge channel C (refrigerant discharge path) (see FIG. 1). The space inside the refrigerant nozzle 5 is referred to as an in-nozzle flow path B. Further, the refrigerant nozzle 5 is inserted into the slit 6 and is fixed in the slit 6 in contact with the side surfaces of the plurality of fins 4.

  Each fin 4 is formed with a plurality (18 in the present embodiment) of through-holes 41 penetrating in the direction in which the fins 4 are arranged. Each through hole 41 is formed by hollowing out the fin 4 into a circle. Further, the plurality of through holes 41 are formed over the entire plane of the fin 4 and penetrate in the thickness direction of the fin 4. Further, in the plurality of fins 4 arranged side by side, the through holes 41 are formed at the same position, and are arranged in a straight line in the arrangement direction of the fins 4. As a result, the refrigerant flows in the direction in which the fins 4 are arranged through the plurality of through holes 41 as indicated by the thick arrows in FIG.

  The refrigerant flow in the cooler 2 will be described with reference to FIGS. 3 and 4 in addition to FIGS. Thick line arrows in FIGS. 3 and 4 represent the flow of the refrigerant. The housing 10 is provided with a refrigerant supply port 12 and a refrigerant discharge port 13. The refrigerant supply port 12 communicates with a space above the partition plate 7 (a space farther than the base plate 3 with the partition plate 7 in between), that is, a refrigerant supply channel A. The coolant discharge port 13 communicates with a space below the partition plate 7 (a space closer to the base plate 3 than the partition plate 7), that is, the coolant discharge channel C, and discharges the coolant to the outside. The refrigerant discharge ports 13 are formed downstream in the refrigerant flow direction (downstream in the direction in which the fins 4 are arranged) and are formed on both sides of the slit 6. The refrigerant supply port 12 is provided at the end of the casing 10 in the direction in which the plane of the fin 4 extends (X-axis direction in the coordinate system in the figure), and the refrigerant discharge port 13 faces the plane of the fin 4. It is provided at the end in the direction (Y-axis direction). In other words, the refrigerant discharge port 13 opens in a direction perpendicular to the direction in which the fins 4 are arranged. A pipe for supplying a refrigerant is connected to the refrigerant supply port 12. A pipe for discharging the refrigerant is connected to the refrigerant discharge port 13. The refrigerant communicates with a reserve tank (not shown), and is supplied to the refrigerant supply port 12 by a pump (not shown).

  The refrigerant supplied from the refrigerant supply port 12 to the inside of the housing 10 flows along the X axis in the figure, passes through the refrigerant supply channel A, passes through the nozzle flow path B, and passes from the tip of the refrigerant nozzle 5 to the back surface of the base plate 3. It is ejected vigorously toward 3b. A semiconductor chip 92 is attached to the front surface 3 a of the base plate 3 via a heat spreader 91. The heat spreader 91 is a heat transfer plate for efficiently transferring the heat of the semiconductor chip 92 to the base plate 3 and is made of copper having a high thermal conductivity. The semiconductor chip 92 corresponds to the cooling target, and the region where the heat spreader 91 is attached corresponds to the cooling target attachment region. The refrigerant nozzle 5 ejects the refrigerant toward the back surface of the cooling target attachment region.

  The refrigerant ejected from the refrigerant nozzle 5 collides with the back surface 3 b of the base plate 3 (particularly, the back surface side of the cooling target attachment region), and then flows along the fins 4. The refrigerant collides with the back surface of the base plate 3 and absorbs heat from the base plate 3 there. Since the refrigerant strongly and continuously collides with the back surface 3 b of the base plate 3, the refrigerant efficiently absorbs the heat of the base plate 3. The refrigerant that has absorbed heat passes between the fins 4 and travels toward the refrigerant discharge channel C. A part of the refrigerant flows in the direction in which the fins 4 are arranged through the through holes 41 of the fins 4.

  The refrigerant that has collided with the back surface 3 b of the base plate 3 also absorbs heat from the fins 4 while passing along the sides of the fins 4. Thereafter, the refrigerant passes through the refrigerant discharge channel C between the fins 4 and the partition plate 7 and is discharged from the refrigerant discharge port 13. A part of the refrigerant flows through the through holes 41 of the fins 4 in the direction in which the fins 4 are arranged (a direction perpendicular to the plane of the fins 4). The refrigerant discharge port 13 is provided at the end of the housing 10 in a direction in which the plane of the fin 4 faces, and the refrigerant crosses the plane of the fin 4 through the refrigerant discharge channel C and the through hole 41 of the fin 4. Flowing into. In other words, the flow direction of the refrigerant in the refrigerant supply channel A and the flow direction of the refrigerant in the refrigerant discharge channel C and the through hole 41 of the fin 4 are substantially orthogonal. The semiconductor chip 92 is efficiently cooled via the heat spreader 91, the base plate 3, and the fins 4.

  The advantages of the structure of the cooler 2 will be described. In the impinging jet type cooler 2, the refrigerant nozzle 5 that ejects the refrigerant toward the back surface 3 b of the base plate 3 is inserted into the slit 6 of the fin 4, and reaches the immediate vicinity of the base plate 3. And the front-end | tip of the refrigerant | coolant nozzle 5 has faced the back surface of the cooling object attachment area | region. Therefore, the refrigerant concentrates and collides with the back surface of the cooling target attachment region, and cools the cooling target efficiently.

  The refrigerant that has collided with the back surface 3 b of the base plate 3 flows along the fins 4. In the fin 4, the side close to the base plate 3 is hot, and the temperature decreases as the distance from the base plate 3 increases. The refrigerant ejected from the refrigerant nozzle 5 first touches the root of the fin 4 (side closer to the base plate 3) and then touches the tip of the fin 4 (side far from the base plate 3). The refrigerant first touches the high temperature region (fin base side) of the fin, and then touches the low temperature side (fin tip side) sequentially, which contributes to the improvement of the cooling efficiency.

  Further, since the refrigerant passes through the through holes 41 and flows in the direction in which the fins 4 are arranged, the refrigerant can be discharged through the through holes 41. Therefore, the space of the refrigerant discharge channel C for discharging the refrigerant can be reduced, and the entire cooler 2 can be reduced in size. Further, since the space of the refrigerant discharge channel C can be reduced, the arrangement positions of the partition plate 7 and the refrigerant nozzle 5 can be brought closer to the fins 4 and the base plate 3. Thereby, since the refrigerant can be ejected from the refrigerant nozzle 5 at a position close to the base plate 3, it is possible to cause the refrigerant to collide with the base plate 3 vigorously and to introduce the refrigerant to the base side of the fins 4. Therefore, the cooling performance is improved. Further, as shown in FIG. 5, even when the height position of the tip 51 of the refrigerant nozzle 5 is not changed, the space of the refrigerant discharge channel C can be reduced, so that the position of the partition plate 7 is brought closer to the fin 4. As a result, the length of the refrigerant nozzle 5 extending from the partition plate 7 can be shortened. Thereby, since the refrigerant nozzle 5 through which the refrigerant passes can be shortened, the pressure loss of the refrigerant in the refrigerant nozzle 5 can be reduced, and the refrigerant can be ejected to the base plate 3 vigorously. Therefore, the cooling performance is improved.

  Next, an example of a method for manufacturing the fin 4 having the through hole 41 will be described. FIG. 6 is a diagram for explaining an example of a method for manufacturing the fin 4 having the through hole 41. (A1) to (d1) in FIG. 6 are cross-sectional views viewed from the side, and (a2) to (d2) are cross-sectional views in predetermined cross sections of (a1) to (d1). When manufacturing the fin 4, first, as shown in FIGS. 6A1 and 6A2, a plurality of through holes 41 are formed in a cubic metal lump 401. When the through-hole 41 is formed, the metal block 401 is cut out in the longitudinal direction with a drill or the like, for example, and penetrated. Next, as shown in FIGS. 6 (b1) and (b2), a plurality of fins 4 are formed by making a plurality of cuts in the vertical direction (short direction) in the metal block 401 in which the through holes 41 are formed. To do. This cut can be made with a known cutting tool. Moreover, the pace plate 3 is formed together with the fins 4 by making the cut from the upper end to the vicinity of the lower end of the metal block 401. Subsequently, as shown in FIGS. 6C1 and 6C2, slits 6 are formed by making cuts in the plurality of fins 4. The slit 6 extends from the upper end of the fin 4 to the pace plate 3 at the center of the fin 4. Thereafter, as shown in FIGS. 6 (d 1) and (d 2), the refrigerant nozzle 5 extending from the partition plate 7 is inserted into the slit 6. The fin 4 having the through hole 41 is manufactured by the method as described above.

  As mentioned above, although one embodiment was described, a specific mode is not limited to the above-mentioned embodiment. For example, in the above embodiment, the through holes 41 of the plurality of fins 4 are formed in a straight line in the direction in which the fins 4 are arranged. However, the present invention is not limited to this configuration. They may be shifted from each other in the direction of alignment. In the above embodiment, 18 circular through holes 41 are formed. However, the number and shape of the through holes 41 are not particularly limited and can be appropriately changed.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

2: Cooler 3: Base plate 3a: Front surface 3b: Back surface 4: Fin 5: Refrigerant nozzle 5a: Engagement protrusion 5b: Engagement recess 6: Slit 7: Partition plate 10: Housing 12: Refrigerant supply port 13 : Refrigerant discharge port 41: Through hole 91: Heat spreader 92: Semiconductor chip A: Refrigerant supply channel B: Nozzle flow path C: Refrigerant discharge channel

Claims (3)

A base plate to which the object to be cooled is attached on one side;
A plurality of fins mounted side by side on the other surface opposite to the one surface of the base plate;
A refrigerant nozzle that ejects the refrigerant from the other surface side toward the base plate,
In each of the fins, slits reaching the base plate are provided in a row so as to cross the plurality of fins, and a plurality of through holes penetrating in the direction in which the fins are arranged are formed. . A refrigerant discharge port for discharging the refrigerant ejected from the refrigerant nozzle to the outside;
The cooler according to claim 1, wherein the refrigerant jetted from the refrigerant nozzle toward the base plate flows through the through holes in the direction in which the fins are arranged, and is discharged to the outside from the refrigerant discharge port.   The cooler according to claim 1 or 2, wherein the refrigerant nozzle is inserted into the slit.

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