JP5435428B2 - Radiator with foil-like radiating fin and method for forming the same - Google Patents

Description

  The present invention relates to a radiator having a foil-like radiation fin, and more particularly, to a radiator suitable for a metal base printed board integrally provided with a heat radiation part for radiating heat generated from electronic components and the like, and a method of forming the same. .

  In recent years, electronic components have been miniaturized, densified and highly functionalized in accordance with demands for high performance and miniaturization of electronic devices, and are mounted on circuit boards at high density. Along with this, the temperature of electronic components is rising, and heat dissipation is very important. Conventionally, various methods have been proposed for heat dissipation, and some of them have been put to practical use.

  As an example, the present applicant disclosed in Japanese Patent Application Laid-Open No. 2009-32755 (Patent Document 1) a plurality of plate-like heat radiation fins by digging up one side of a metal plate having good thermal conductivity and repeatedly digging up with a tool. We proposed a heatsink that was formed upright. Japanese Unexamined Patent Application Publication No. 2009-54731 (Patent Document 2) has proposed a metal base printed board with a heat radiating portion that can efficiently dissipate heat generated from electronic components and the like through heat radiating fins of the heat radiating portion.

  As shown in FIG. 9, the heat dissipating part in the radiator shown in Patent Document 1 and the metal base printed circuit board shown in Patent Document 2 has a metal plate 100 with good thermal conductivity and a tip side in the moving direction. The digging tool 110 formed with the blade portion 110a is relatively moved in a state having a predetermined angle, and one surface of the metal plate 100 is dug down, so that the plate-like radiating fins 101 are integrally formed upright. Next, the metal plate 100 and the digging tool 110 are relatively moved from the upstream side of the formation pitch from the processing surface 102 on which the radiating fins 101 are erected, and the metal plate 100 is digged up to dig up the next plate shape. The plurality of heat radiation fins 101 are continuously formed on the metal plate 100 by sequentially repeating the digging and raising process.

  As described above, when a heat generating electronic component such as an integrated circuit chip is disposed on the other surface of the radiator in which a plurality of heat dissipating fins 101 are integrally formed upright on one surface of the metal plate 100, the heat generating electronic component generates the heat. Heat is transmitted to the heat radiating fins 101 through the metal plate 100 and is radiated from the surface of the heat radiating fins 101 into the air. At this time, since the base end portion of the heat radiating fin 101 is integrally connected to one surface of the metal plate 100, heat generated from the heat generating electronic component is quickly transmitted to the heat radiating fin 101, so that heat radiation efficiency is improved. In addition, since a cooling medium such as air is circulated between the plurality of heat radiating fins 101, heat is quickly radiated from the surface of the heat radiating fins 101, so that the heat radiating efficiency can be further enhanced.

JP 2009-32755 A JP 2009-54731 A

  In the radiator formed by the above-described method, a relatively large interval is required in order to distribute the cooling medium between the plurality of radiating fins 101. Thus, if it is going to form the space | interval between adjacent radiation fins 101 large, as shown in FIG. 9, the plate | board thickness t of the radiation fin 101 will necessarily become thick. Since the radiating fin 101 is formed by digging the metal plate 100 with the digging tool 110 as described above, the stress on the metal plate 100 increases as the plate thickness t1 increases. As a result, as shown in FIG. 9, a concave groove 103 parallel to the plate-like heat radiation fin 101 is formed on the other surface of the metal plate 100.

  When the metal plate 100 in which the concave groove 103 is formed in this way is applied to the metal base printed board with a heat dissipation portion shown in Patent Document 2, as shown in FIG. 10, the other surface of the metal plate 100 and the adhesive layer The metal foil 104 for wiring that is bonded through the film is peeled off, and a gap 105 is formed. In a normal case, the metal base printed board is soldered by placing the electronic component 106 with a mounter and then placing it in a solder reflow. When this soldering is performed, the temperature becomes high, so that the air in the gap 105 expands, causing a problem that the metal foil 104 and the resist 107 are cut. Even if it does not peel off, when it is put in the solder reflow, air bubbles are generated in the concave groove 103, and the solder between the electronic component 106 and the metal foil 104 as shown in the W part of FIG. There was a problem of causing poor connection.

  In order not to generate the concave groove 103 as described above, it is desirable to reduce the thickness of the radiating fin 101 to such an extent that no stress is applied to the metal plate 100, but when the radiating fin 101 is formed with a small thickness. Inevitably, the interval between adjacent heat dissipating fins 101 is reduced. For this reason, since the cooling medium does not sufficiently flow between the heat radiating fins 101, there arises a problem that the cooling efficiency is impaired.

  Therefore, an object of the present invention is to significantly reduce the stress when forming a heat radiating fin on one side of a metal plate, to prevent a concave groove formed on the other side, and to reduce the weight of the radiator itself. It is an object of the present invention to provide a radiator and a method for forming the same.

In order to solve the above-described problems, a radiator having a foil-like heat radiation fin according to the present invention has a heat radiation having a plurality of plate-like heat radiation fins erected at predetermined intervals on one surface of a metal plate. part is a radiator that is provided integrally with the heat radiation fins, by the tool dig up the metal plate is formed upright on the foil dig up more than one-half of the thickness of the metal plate, adjacent each Cutting portions having a predetermined width are respectively formed on the bottom surfaces between the heat radiation fins, and the cutting portions of the next heat radiation fin that is once erected after the one heat radiation fin is formed upright. It is formed by cutting the base end, and by repeating the base end cutting of the radiating fin by an integral number of times , the width of the cutting portion formed between the adjacent radiating fins is set to the thickness of the radiating fin. Forming more than twice It is the gist.

  The metal plate is a metal base printed board in which a metal foil for wiring is bonded to the other surface via an adhesive layer, and at least one heat-dissipating heat-generating electronic component is mounted on one surface of the metal plate. The heat dissipating part is integrally formed at the facing position.

Further, in the method of forming a radiator including the foil-like radiation fin according to the present invention, the one surface of the metal plate and the digging tool in which the blade portion is formed on the tip side in the moving direction have a predetermined angle. Digging up and forming the foil-like radiating fins upright by digging up to one-half or more of the plate thickness from one side of the metal plate by the blade portion of the digging and raising tool by relative movement in the state; and By moving the metal plate and the digging tool relative to each other from the upstream side of the forming pitch from the work surface formed by standing formation of the heat radiating fins, the following foil shape is obtained by digging up the metal plate with the digging tool. after the heat dissipating fin is formed upright integrally, the cutting portion by moving said gouging tool horizontally cutting the base end of the heat radiation fins for this next the heat radiation fins ; And a cutting step of forming, after standing formed by the steps dig up one of the radiation fins, once erected the formed by repeating a cutting step of cutting the base end of the heat radiation fins, the width of the cutting portion The gist of the present invention is to form a heat radiating portion formed twice or more the plate thickness of the heat radiating fin.

The intervals between the radiating fins that are erected in the digging process and the radiating fins that are erected in the cutting process are equal, and the cutting process is performed an integral multiple of 1 or more during the digging process, Are formed at equal intervals or unequal intervals.

According to the radiator with the foil-like heat radiation fin according to the present invention, the metal plate is dug up on one surface of the metal plate, and the heat radiation fin is formed upright in a foil shape by a tool. The stress when forming the fin can be greatly reduced, and the concave groove formed on the other surface can be prevented beforehand. Further, the cutting part formed on the bottom surface between each of the adjacent radiating fins is formed by cutting the base end of the next foil-shaped radiating fin that has been erected and formed, so that the cutting part is formed. In this case, the stress can be greatly reduced, and the concave groove formed on the other surface of the cutting portion can be prevented in advance. Moreover, since the cutting part formed in the bottom surface between the said adjacent radiation fin is formed in width more than twice the plate | board thickness of a radiation fin, it becomes possible to distribute | circulate a cooling medium to this cutting part, High heat dissipation efficiency can be ensured. In addition, while forming the foil-shaped heat radiation fins upright, by forming a cutting portion on the bottom surface between the heat radiation fins, the heat radiation fins are formed upright by digging down to half or more of the plate thickness of the metal plate. However, it is difficult for a concave groove to be formed on the other surface, and the radiator itself can be reduced in weight.

  When the metal plate is a metal base printed circuit board in which a metal foil for wiring is bonded to the other surface via an adhesive layer, the heat radiation part is opposed to the position of the heat generating electronic component mounted on the printed circuit board. Thus, the heat generated from the heat generating electronic component can be directly and efficiently radiated by the heat radiating portion.

According to the method of forming a radiator including a foil-like heat radiation fin according to the present invention, a dug-up process of standing up and forming a foil-like heat radiation fin integrally on one surface of a metal plate by a dug-up tool, and once standing upright The heat radiation portion can be easily formed by repeatedly digging up the base end of the next foil-shaped heat radiation fin and cutting it with a tool to form the cut portion. At this time, since the heat radiating portion made of a foil-shaped heat radiating fin with a cutting portion formed therebetween is directly formed on the metal plate, the structure of the heat radiating means is simplified and the number of parts is reduced, thereby reducing the cost. It becomes possible. In particular, the metal plate is dug up and the heat radiating fins are erected in a foil shape by means of a tool, so that the stress when forming the heat radiating fins on one side of the metal plate can be greatly reduced, and the recesses caused by stress on the other side can be reduced. Grooves can be prevented beforehand. Moreover, since the cutting part is formed by the cutting process between the foil-shaped heat radiation fins, the heat radiation fins are appropriately separated, and the cooling medium can be distributed efficiently. Furthermore, by forming the foil-shaped heat radiation fins by digging up to one-half or more of the thickness of the metal plate, the plate thickness at the cutting portion is formed to be less than or equal to one-half of the metal plate. This makes it possible to reduce the overall weight of the heatsink in combination with the weight reduction by the heat radiation fins.

  The radiating fins erected in the digging process and the radiating fins erected in the cutting process are equally spaced or equally spaced, and the number of cutting processes performed during the digging process is an integer multiple of 1 or more. Thereby, since the radiation fins are formed at regular intervals, it becomes possible to simplify the processing machine and its control. As a result, it becomes easy to form between the radiating fins in the radiating portion at an arbitrary interval of equal intervals or unequal intervals.

  The heat radiator provided with the foil-shaped heat radiation fin according to the present invention is integrally provided with a heat radiation portion including a plurality of plate-shaped heat radiation fins standing upright at predetermined intervals on one surface of the metal plate. The heat radiating fins are formed upright in a foil shape by digging up the metal plate to a half or more of the thickness of the metal plate with a tool, and a cutting portion is formed on the bottom surface between the adjacent heat radiating fins. The width of the cutting part is formed to be twice or more the plate thickness of the radiating fin.

In the digging and raising step, the foil-like radiating fin in the radiator having the foil-like radiating fin is moved relatively in a state having a predetermined angle after the blade portion of the digging tool is brought into contact with one surface of the metal plate. By digging from one side of the metal plate by the blade portion of the digging tool, the digging tool is integrally formed upright. Next, in the cutting process, the metal plate and the digging tool are relatively moved from the upstream side of the formation pitch from the work surface formed by the standing formation of the radiating fin, and the metal plate is moved by the digging tool. The next foil-shaped heat radiation fin is integrally formed upright by digging up, and then the digging and raising tool is moved in the horizontal direction to cut the base end of the next heat radiation fin to form a cutting portion. Then, the said digging up process and cutting process are repeated, and the heat radiator provided with the foil-shaped radiation fin is formed. At this time, the width of the cutting portion is formed to be twice or more the plate thickness of the heat radiating fin.

  Next, a radiator having a foil-like heat radiation fin according to the present invention will be described in detail with reference to the drawings.

  The heat radiator 1 shown in FIGS. 1 and 2 uses a metal plate 2 such as copper, iron, iron-nickel alloy, or aluminum having good thermal conductivity as a base material. 1 and 2 show an example in which the metal plate 2 is a metal base printed board. That is, the metal base printed circuit board has a metal foil 3 such as a copper foil bonded to the other surface 2 b of the metal plate 2 via an insulating adhesive layer 4. The adhesive layer 4 uses, for example, a thermosetting resin such as a high heat resistant epoxy resin as a base resin. As is well known, a predetermined wiring pattern is formed on the metal foil 3 by chemical etching. If necessary, a resist made of an electrically insulating film is coated except for the land of the wiring pattern.

  The heat radiating portion 5 is integrally formed on the one surface 2 a of the metal plate 2. The heat dissipating part 5 is composed of a plurality of foil-shaped heat dissipating fins 6. As shown in FIG. 2, the base end portion of the heat radiating fin 6 is integrally connected from one surface 2 a of the metal plate 2. Further, the radiation fins 6 are erected at the same interval, and cutting portions 7 having a predetermined width are formed between the radiation fins 6. And although the cutting part 7 between each radiation fin 5 is formed substantially flat, since it cuts by the method mentioned later, the cutting trace 7a made into the slightly uneven surface is formed. Since the cutting portion 7 digs up and digs up the tool up to half or more of the plate thickness of the metal plate 2 when the radiating fin 6 is formed upright from the metal plate 2, the recess 8 is formed. . The thickness of the recess 8 formed by the cutting portion 7 is less than or equal to one half of the thickness of the metal plate 2. Further, a flange 9 having a thickness of the metal plate 2 itself is formed around the heat radiating portion 5.

  Moreover, since the plate | board thickness of the radiation fin 6 is formed by digging up with the thin cutting allowance from one surface of the metal plate 2, it forms in thin foil shape, The plate | board thickness is 0.02 mm-0.5 mm. . Further, the width of the cutting portion 7 formed between the heat radiating fins 6 is set to 0.04 mm or more. The width of the cutting portion 7 is formed to be twice or more the plate thickness of the heat radiating fin 6. As described above, the width of the cutting portion 7 formed between the adjacent heat radiating fins 6 is to sufficiently circulate a cooling medium such as cooling air, thereby increasing the heat radiation efficiency. The heat radiation part 5 can be obtained.

  Next, a method for forming the heat radiating portion 5 of the radiator 1 will be described with reference to FIG. The metal plate 2 is preferably copper or aluminum as a metal plate having good thermal conductivity and good machinability. Further, the thickness of the metal plate 2 is preferably 1 mm to several mm used in a normal electronic circuit. A metal foil 3 such as a copper foil is bonded to the other surface 2b of the metal plate 2 via an insulating adhesive layer 4 in advance, and a predetermined wiring pattern is formed on the metal foil 3 by etching. And configured as a metal-based printed circuit board. In the state before the heat radiating part 5 is manufactured, no electronic component is provided. The metal plate 2 is placed on a pressing device (not shown). Thereafter, the radiating fins 6 are formed upright by the digging tool 10.

  The digging tool 10 is formed with a blade 10 a perpendicular to the moving direction at the tip on the bottom side, and its width is set to a width necessary for the heat radiating part 5. Further, the digging tool 10 is attached to a driving device (not shown) so as to be inclined at a predetermined angle θ so that the rear end side becomes higher with respect to one surface of the metal plate 2. The inclination angle θ is appropriately set depending on the height of the heat radiating fins 6, the plate thickness, the material of the metal plate 2, and the like, but is generally set to 5 degrees to 20 degrees. Both sides in the width direction of the digging tool 10 are formed substantially at right angles, but both sides on the bottom surface side where the blade portion 10a is formed may be formed in a tapered shape or an arc shape that becomes narrower as it reaches the bottom surface. good.

  First, in the digging process shown in FIG. 6 (A), the cutting edge 10a of the digging tool 10 is positioned at a position P where the cutting allowance upstream of the work surface 2c formed in advance on the one surface 2a of the metal plate 2 is obtained. Make contact. This cutting allowance is set to a thickness of about 0.2 mm to 1.0 mm in order to form the radiating fin 6 in a thin foil shape. Setting a thin cutting allowance is important in order to prevent stress from being applied to the metal plate 2 when the radiating fins 6 are erected and formed later by the tool 10.

  And after making the blade part 10a of the digging tool 10 contact | abut to the predetermined position P of the one surface 2a of the metal plate 2, the digging tool 10 is driven by the drive device at a predetermined angle θ in the direction of the arrow. When moving in the direction of the other surface 2b, thin foil-like heat radiation fins 6 are formed upright. At this time, the digging tool 10 is moved to a depth of one half or more of the thickness of the metal plate 2. Then, due to the standing formation of the radiating fins 6, a work surface 2 c that is inclined equal to the inclination angle of the digging tool 10 is formed on the one surface 2 a of the metal plate 2.

  Following this excavation process, the process proceeds to a cutting process. First, the metal plate 2 and the digging tool 10 are moved relative to each other, and the cutting edge 10a is located upstream of the surface 2c to be processed at a position where the same cutting allowance is obtained as when the above-described radiating fin 6 is formed. Make contact. Then, the digging tool 10 is moved at a predetermined angle in the direction of the arrow to the same depth as when the radiating fin 6 is formed, and the next radiating fin 6 is erected as shown in FIG. 6B. . At this time, since the cutting allowance is set thin, the distance from the radiating fins 6 that are erected in advance is very small.

  Thereafter, with the next radiating fin 6 standing and formed, the digging tool 10 is moved in a horizontal direction parallel to the metal plate 2 as indicated by an arrow in FIG. By this horizontal movement, the base end of the next radiating fin 6 is cut into scrap. At this time, the scrap separated from the metal plate 2 is sandwiched between inner walls 8a of the recesses 8 to be described later, so that scattering is prevented. Thereby, the cutting part 7 is formed in the metal plate 2.

  By cutting one radiating fin 6, a cutting portion 7 having a width about twice the thickness of the radiating fin 6 is formed. When the radiating fin 6 is formed in a foil shape, since the width of the cutting portion 7 is small, the cutting process is repeated a plurality of times in order to increase the width of the cutting portion 7. That is, as shown in FIG. 6D, the next radiating fin 6 is formed in the same manner as the method of forming the radiating fin 6 again by bringing the blade portion 10a of the digging tool 10 into contact with the upstream side. Thereafter, as shown in FIG. 6 (E), the digging tool 10 is moved in the horizontal direction to cut the base end of the next radiating fin 6. At this time, the scrap is detached from the metal plate 2 but is sandwiched between the inner walls 8a on both sides of the recess 8 described later. As a result, the width of the cutting part 7 is doubled. The width of the cutting portion 7 can be set as appropriate. However, if it is desired to further increase the width, it can be realized by increasing the above-described cutting step a predetermined number of times.

  Thus, in the cutting process, after the cutting part 7 having a predetermined width is obtained, the process proceeds to the next digging process, and as shown in FIG. Adjacent radiating fins 6 are formed upright. Thereafter, by repeating the cutting process of one or more integral multiples after one digging process, a plurality of heat radiation fins 6 are formed on one surface 2a of the metal plate 2 as shown in FIGS. The heat radiating portion 1 is formed standing upright at equal intervals.

  FIG. 3 shows a two-dot chain line from the position where the original radiating fin 6 is erected by repeating the cutting process five times after the radiating fin 6 is erected and formed in one digging process. 5 shows a state where the five radiating fins 6 are cut and removed. As a result, as shown in the drawing, a cutting portion 7 having a width of about 10 times the plate thickness of the radiation fin 6 can be formed.

  FIG. 4 shows that a plurality of heat dissipating fins 6 can be removed by reducing the number of cutting steps at a predetermined position on the one surface 2a of the metal plate 2 and making the width of the cutting portion 7 different from one digging step. An example of standing upright at equal intervals is shown. Incidentally, in the example shown in FIG. 3, the heat radiation fins 6 on the one surface 2 a of the metal plate 2 facing the heat generating electronic component 12 on the right side of the figure are formed at a close interval, and heat is dissipated at positions far from the other heat generating electronic components 12. The fins 6 are formed at rough intervals. In this way, by varying the number of radiating fins 6 that are erected to match the position of the heat generating electronic component 12, while ensuring the heat radiation efficiency at the required position, the number of the heat radiation fins 6 is reduced at other positions, Further weight reduction can be achieved.

  FIG. 5 shows a cross-sectional view of the radiator 1. In the above-described digging process and cutting process, when the radiating fins 6 are formed upright on the metal plate 2 by the digging tool 10, the base end side of the radiating fins 6 is slightly thicker and at the same time as shown by the arrows in FIG. In addition, it bulges in both directions. For this reason, the base end side of the radiation fin 6 is joined in pressure contact with the inner wall 8 a of the recess 8. As a result, even if the heat dissipating fin 6 is thinly formed in a foil shape, the base end side is held by the metal plate 2, so that the mechanical strength can be increased. Moreover, since both sides in the vicinity of the base end of the radiating fin 6 are thermally connected to the metal plate 2, it is possible to improve the radiating efficiency. Moreover, since the base end side of the radiation fin 6 is hold | maintained at the inner wall 8a of the recess 8, even if it cuts the base end side of the radiation fin 6 in a cutting process, it is hold | maintained in the recess 8 without being scattered. Therefore, it is possible to prevent an accident that the scrap adheres to the above-described processed surface 2c and inhibits the excavation and machining.

  In FIGS. 1 and 2, on the upstream side of the radiating fin 6, an inclined processing surface 2 c that extends from the bottom surface of the recess 8 to one surface of the metal plate 2 remains. The inclined surface that is the surface to be processed 2c can act as a heat radiating surface. Further, on the rear side of the work surface 2 c and on both sides of the plurality of heat radiation fins 6, the flange portions 9 having the thickness of the metal plate 2 are formed. Since the flange 9 has a high mechanical strength, it can protect the heat-radiating fins standing up in a thin foil shape, and can prevent deformation and the like.

  The heat dissipating part 5 is formed at a position corresponding to a heat generating electronic component 12 such as an integrated circuit disposed in a wiring pattern formed by the metal foil 3 on the other surface 2b of the metal plate 2. By installing the heat dissipating part 5 in such a positional relationship, heat generated from the heat generating electronic component 12 is transmitted to the heat dissipating part 5 through the metal plate 2 and is dissipated from the surface of the heat dissipating fins 6 into the air. At this time, even if the radiation fins 6 are formed in a foil shape, if the heat capacity of the plurality of radiation fins 6 is larger than the heat generation amount of the heat generating electronic component 12, the radiation fins 6 have a sufficient surface area, and cutting As long as a sufficient cooling medium flows through the portion 7, necessary heat radiation efficiency can be obtained. In addition to the integrated circuit, the heat generating electronic component 12 includes a power transistor, a resistor, a power module, and the like.

  The metal plate 2 constituting the metal base printed board formed as described above has an electronic component such as an integrated circuit, a resistor, a capacitor, or a chip of the electronic component 12 on a wiring pattern provided on the other surface 2b by a chip mounter or the like. Arranged. Thereafter, the other surface of the metal plate 2 is electrically connected by soldering the chip of the electronic component 12 and the wiring pattern by reflow. At this time, the other surface 2b of the metal plate 2 is formed by standing up the radiating fins 6 in a thin foil shape, so that stress in the digging process is greatly reduced. The concave groove 103 is not formed. As a result, air bubbles are generated in the concave groove 103 to prevent poor connection between the electronic component and the metal foil, or peeling or cutting of the wiring pattern during reflow. It became possible to improve.

  In the above-described embodiment, the heat radiation comprising the plurality of heat radiation fins 6 on the one surface 2a of the metal plate 2 in a state where the wiring pattern and the resist are provided in advance on the other surface 2b of the metal plate 2 and no electronic components are disposed. The part 5 is formed. However, as described above, when the radiating fins 6 are formed upright in a thin foil shape, the weight and stress in the digging process are greatly reduced, so that the electronic components are placed on the wiring pattern provided on the other surface of the metal plate 2. After the disposition, the heat radiating portion 5 including the plurality of heat radiating fins 6 can be formed on the one surface 2a of the metal plate 2. In this embodiment, as described above, the groove 103 due to stress is not formed. However, depending on the thickness and material of the metal plate 2, the heat radiating portion 5 is formed on the one surface 2 a of the metal plate 2 to form the metal. The plate 2 may be curved. At this time, as described above, it is desirable to form the heat radiating portion 5 after the electronic component is disposed on the other surface of the metal plate 2.

  FIG. 7 shows an example in which the radiator 1 is formed from a hoop-shaped metal plate 20. The hoop-like metal plate 20 is made of copper or aluminum as a metal plate having good thermal conductivity and good machinability, as in the example described above. A plurality of heat radiation fins 22 are formed on one surface of the hoop-shaped metal plate 20. On both sides of the hoop-shaped metal plate 20, pilot holes 20 b are provided for fixing the position and for transferring each predetermined dimension. The method of forming the radiation fins 22 on the hoop-shaped metal plate 20 is formed upright by the digging tool 10 in the same manner as in the above-described example.

  That is, after the blade portion 10a of the digging tool 10 is brought into contact with a predetermined position on the one surface 20a of the hoop-shaped metal plate 20, the digging tool 10 is moved in a predetermined angle direction by a driving device, so that a thin foil-like shape is obtained. The heat radiating fins 22 are formed upright. At this time, in order to form the radiation fin 22 in a thin foil shape, the thickness is set to about 0.2 mm to 1.0 mm. By setting the cutting margin thin in this way, when the radiating fins 22 are formed upright, no stress is applied to the metal plate 20, and as a result, a concave groove is formed on the other surface of the hoop-shaped metal plate 20. Can be prevented beforehand.

  After this digging process, the cutting part 23 is formed in a cutting process. That is, the next radiating fin 6 is erected on the one surface 20 a of the hoop-like metal plate 20 by the digging tool 10. The cutting allowance at this time is also set as thin as when the above-described radiating fin 22 is formed upright. Therefore, the space | interval with the radiation fin 22 which stood | started up previously is a micro dimension. Thereafter, in a state where the next radiating fin 22 is formed upright, the digging tool 10 is moved in a horizontal direction parallel to the hoop-shaped metal plate 20 and the base end of the next radiating fin 22 is cut, thereby forming the hoop-shaped metal plate. The cutting part 23 is formed in 20. In the example shown in FIG. 7, the cutting process is repeated 3 to 5 times to increase the width of the cutting portion 23 and to have a size 5 to 10 times larger than the plate thickness of the radiation fin 22.

  Thereafter, the radiating fins 22 are formed upright by the digging process again, and then the cutting process is repeated 3 to 5 times to form the next cutting portion 23. In this way, by repeating the digging process and the plurality of cutting processes, the plurality of heat radiation fins 22 are formed upright on the one surface 20a of the hoop-shaped metal plate 20 in sequence. And the collar part 24 is formed in the position in the pilot hole 20b provided in the both sides of the several radiation fin 22. FIG.

  When the radiating fins 22 are sequentially formed upright on the one surface 20a of the hoop-shaped metal plate 20, a long radiating portion is formed. A radiator having a predetermined length can be obtained by cutting the cutting portion 23 at a predetermined position.

FIG. 8 shows an example in which three sets of heat dissipating portions 31, 32, and 33 are separated from each other on one surface 30 a of the long metal plate 30. In this example, the heat radiating portions 31, 32, and 33 are sequentially provided with a plurality of heat radiating fins 34, 35 on the one surface 30 a of the metal plate 30 by repeating a digging process and a plurality of cutting processes as in the above-described example. , 36 are formed upright, and cutting portions 37, 38, 39 are formed between the radiation fins 34, 35, 36, respectively. The formation method of these heat radiation parts 31, 32, and 33 is the same as that of the example mentioned above, The description is abbreviate | omitted. In addition, between the heat radiating portions 31, 32, 33, long planar portions 40, 41 are formed in which the bottom plate thickness is smaller than the plate thickness of the metal plate 30.

  Further, the example shown in FIG. 8 is different from the above-described example in that the width of the heat radiating portions 31, 32, 33 is formed to be equal to the width of the metal plate 30. Thus, if each width | variety is made equal, since a collar part will not be formed in the both sides of a thermal radiation part, mechanical strength will become low and it will become easy to bend in a longitudinal direction. This property can be used, for example, as a flexible metal base printed board, and a printed wiring board can be disposed along a structure with a curved surface.

The long flat surface portions 40, 41 formed between the plurality of spaced heat radiation portions 31, 32, 33 are the same as the cutting portions 37, 38, 39 formed between the heat radiation fins 34, 35, 36. Formed. That is, in the region of the plane portion 40, by performing a predetermined number of times only by continuous cutting process, it is possible to form the flat portion 40 of any size.

  Although the present invention has been specifically described above based on the embodiments, it is needless to say that the present invention is not limited to the above embodiments and can be variously modified without departing from the gist thereof. For example, the metal plate may be formed in an appropriate shape other than a square. Moreover, in the Example mentioned above, although the radiation fin of the several thermal radiation part was formed in parallel, you may vary the direction of a thermal radiation fin for a suitable angle for every thermal radiation part. Furthermore, since the metal plate has a relatively large strength, another mechanism component or the like may be attached to the metal plate.

It is a perspective view which shows the Example of the heat radiator provided with the foil-shaped heat radiation fin concerning this invention. It is a sectional side view which shows the heat radiator provided with the foil-shaped radiation fin shown in FIG. It is an expanded sectional view which shows the heat radiator provided with the foil-shaped radiation fin. It is an expanded sectional view which shows the modification of the heat radiator provided with the foil-shaped radiation fin. It is front sectional drawing which shows the heat radiator provided with the foil-shaped radiation fin shown in FIG. (A) thru | or (F) is process explanatory drawing which shows the process of forming the thermal radiation part of the heat radiator provided with the foil-shaped thermal radiation fin. It is a perspective view which shows the Example which formed the thermal radiation part in the hoop-shaped metal plate. It is a perspective view which shows the Example which formed the several thermal radiation part in the elongate metal plate. It is principal part sectional drawing of the conventional heat radiator. It is principal part sectional drawing which shows the conventional metal base printed circuit board.

DESCRIPTION OF SYMBOLS 1 Radiator 2 Metal plate 2a One end 2b The other side 2c Processed surface 3 Metal foil 4 Insulating adhesive layer 5 Heat radiation part 6 Heat radiation fin 7 Cutting part 9 Gutter part 10 Digging tool 10a Blade part 12 Heating electronic component

Claims (4)

On the one surface of the metal plate is a heat radiator in which a heat radiating portion provided with a plurality of plate-shaped heat radiating fins erected at predetermined intervals is integrally provided,
The radiating fin is formed upright in a foil shape by digging up the metal plate to a half or more of the thickness of the metal plate with a tool.
The bottom surface between each said radiation fins adjacent the cutting portion having a predetermined width are respectively formed,
The cutting portion is formed by cutting the base end of the next heat radiating fin that is once erected and formed after the one heat radiating fin is erected.
The cutting of the base end of the radiating fin is repeated an integral number of times, so that the width of the cutting portion formed between adjacent radiating fins is formed to be twice or more the plate thickness of the radiating fin. A radiator with a foil-like radiation fin.   The metal plate is a metal base printed board in which a metal foil for wiring is bonded to the other surface via an adhesive layer, and at least one heat-dissipating heat-generating electronic component is mounted on one surface of the metal plate. The heat radiator provided with the foil-like heat radiation fin according to claim 1, wherein the heat radiation portion is integrally formed at a facing position. One surface of the metal plate is moved by a relative movement of one surface of the metal plate and a digging tool having a blade portion formed on the front end side in the moving direction in a state having a predetermined angle. Digging up the foil-like heat radiation fins upright integrally by digging up to 1/2 or more of the plate thickness from,
The metal foil and the digging tool are relatively moved from the upstream side corresponding to the formation pitch from the work surface formed by the standing formation of the heat radiating fins, and the metal plate is digged up by the digging tool to produce the next foil. Cutting step of forming a cutting part by moving the digging tool horizontally with respect to the next radiating fin and cutting the base end of the radiating fin, Comprising
After the one radiating fin is erected and formed by the digging and raising process, a cutting process of cutting the base end of the radiating fin once erected is repeated, and the width of the cutting portion is twice the thickness of the radiating fin. A method of forming a radiator having a foil-like heat radiation fin, wherein the heat radiation portion formed as described above is formed. The intervals between the heat radiation fins that are erected in the digging process and the heat radiation fins that are once erected in the cutting process are equal, and the cutting process is performed an integer multiple of 1 or more during the digging process, and the heat radiation. The method of forming a radiator provided with the foil-like heat radiation fin according to claim 3 , wherein the heat radiation fins in the section are formed at equal intervals or at irregular intervals.

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