JP4016849B2 - Die casting mold for radiator and radiator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a die-casting die for a radiator and a radiator, and more particularly, to a die-casting die for a radiator having a cavity that molds a thick portion and a plurality of radiating fin portions, and a radiator made by the die.
[0002]
[Prior art]
In order to prevent the temperature of the heating element from rising, heat radiators are widely used. For example, as shown in FIG. 1, the basic configuration includes a heat sink body 101 that is in close contact with the heating element 105 and receives heat, and heat radiating fins 102 that protrude outward from the heat sink body to dissipate the heat to the cooling medium. . An example of the heating element 105 is a power control device for driving a motor. In recent years, power control devices have been miniaturized, and accordingly, there is a strong demand for miniaturization of radiators. In order to reduce the size of the radiator without impairing the heat dissipation characteristics, it is necessary to increase the surface area of the heat dissipation fin per unit volume. To that end, minimizing the fin pitch and increasing the number of radiating fins attached to a certain area of the heat sink body are effective. In general, a screw 104 is used to fix the radiator 100 and the heating element 105, and a screw hole is conventionally formed in the heat sink body 101. However, as a result of pursuing downsizing of the radiator, the heat sink body 101 no longer has a capacity for forming a screw hole or the like, and a thick fixing portion 103 for opening a screw hole or the like for fixing the heating element 105 is separately provided. It is necessary.
[0003]
There is a casting method as a method for producing a radiator having such a complicated structure. The casting method is a method in which a molten metal is poured into a mold having a cavity having a desired shape, and is cooled and hardened to produce a desired shape. The mold is called a mold, and the molten metal is called molten metal. A feature of this technique is a molding ability that allows a desired shape to be created even if it is extremely complicated. Furthermore, a type of casting that involves casting under high pressure is called die casting. The die-casting method is characterized by being capable of producing thin ones with high dimensional accuracy and being suitable for mass production because it can reduce processing in the subsequent process.
[0004]
However, in the die casting method, there is a problem that when the molten metal is injected into the cavity, air entrained in the cavity or gas generated from the molten metal remains in the molten metal, and a nest is formed in the product. In particular, since the thick structural portion solidifies at the end, the molten metal is not replenished, and a sink nest (contracted nest) is likely to be formed. The nest is a serious defect that affects the quality of the radiator.
[0005]
Therefore, a local pressurization (squeeze) method for locally pressurizing a thick structural part after the molten metal is filled in a mold has been developed, and is widely used as a die casting technique with few cast holes (for example, Patent Documents) 1).
[0006]
[Patent Document 1]
JP-A-8-141723
[Problems to be solved by the invention]
FIG. 2 shows a cross-sectional view of a conventional radiator die casting mold. The mold 200 includes an upper mold 201 and a lower mold 202, a cavity 203 that molds a heat sink body that receives heat from a heating element, a cavity 205 that molds a thick portion protruding outward from the heat sink body, and a heat sink A cavity 208 is formed to mold a plurality of radiating fins protruding outward from the main body. The mold also includes a molten metal injection port (not shown) for injecting molten metal and a local pressurization port 204 for performing local pressurization. The local pressurizing port 204 is provided at a position facing the thick part cavity 205 that molds the thick part. In order to reduce the size of the radiator and provide high heat dissipation characteristics, it is necessary to reduce the fin pitch and increase the surface area of the fin. Therefore, in the mold 200, the fin molds 206, 207, and 209 are thin.
[0008]
In this mold 200, the local pressurization performed after molten metal injection | pouring is demonstrated.
[0009]
When a high pressure is applied to the injected molten metal from the local pressurization port 204, the molten metal fills the air entrapped in the cavity and the holes of the generated gas. Because it solidifies while applying pressure, it is possible to cast a radiator without a void. Due to the movement of the molten metal filling the holes, a flow from the local pressurizing port to the back of the cavity is generated as a whole. The pressure by this local pressurization is applied to the mold in the hot water flow direction from the local pressurization port via the molten metal. A particularly high pressure is applied to the fin dies 206 and 207 in the vicinity of the local pressurizing port in the direction of the molten metal flow. Due to this pressure, there is a problem that the fin dies 206 and 207 near the local pressurizing port are deformed or collapsed.
[0010]
It is an object of the present invention to provide a mold having a structure in which a heat sink having a small fin pitch without a cast hole is formed and the mold does not collapse.
[0011]
[Means for Solving the Problems]
The die casting mold for a radiator of the present invention includes a heat sink body, a thick portion protruding from the heat sink body, and a plurality of heat radiation fin portions protruding from the heat sink body in the same direction on the same side as the thick portion with respect to the heat sink body. When, in the die-casting die having a mold taking cavity and a heat sink body, and a thick wall thickness portion from the heat dissipating fin portion, a plurality of heat dissipating fins and, applying station unit pressure to the mold takes molten metal injected into the cavity the local pressure The pressure port is provided at a position opposite to the thick part cavity that molds the thick part, and the fin mold part that molds the heat dissipating fin part in the vicinity of the local pressure port is located on the fin mold part away from the local pressure port. It is characterized by having a structure with an increased thickness .
[0012]
The thick part of the die cast mold for a radiator according to the present invention may be a fixing part that forms a screw hole for fixing to a heating element.
[0014]
The fin part of the die-casting die for a radiator of the present invention may have a flat plate shape.
[0015]
The radiator of the present invention is a radiator manufactured by these molds.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described using examples. FIG. 3 is a cross-sectional view of a die-casting die for a radiator that is an embodiment of the present invention. The die casting mold 300 is composed of an upper mold 301 and a lower mold 302. The cavity of the die-casting mold 300 is in close contact with the heating element, and is used to dissipate the heat to the cooling medium, the heat sink body 303 that receives heat, the thick part 305 that protrudes outward from the heat sink body 303 for fixing to the heating element. A heat radiating fin portion 308 protruding outward from the heat sink body 303 is formed. Further, the upper die 301 is provided with a local pressurizing port 304 for locally pressurizing the molten metal at a position facing the thick portion cavity 305. In order to apply a sufficient pressure to the thick part cavity 305, it is desirable that the local pressurization port 304 is at a position facing the thick part cavity 305. In order to reduce the size of the radiator and provide high heat dissipation characteristics, it is necessary to reduce the fin pitch and increase the surface area of the fin. Therefore, in the die-cast mold 300, the fin mold 309 is thin, but the thickness of the heat dissipating fin mold sections 306 and 307 near the local pressurization port to which the highest pressure is applied is the thickness of the fin mold 309. The structure is increased as compared with the outer radiating fin type 309.
[0017]
In this mold 300, the local pressurization performed after the molten metal injection will be described.
[0018]
When a high pressure is applied to the filled molten metal from the local pressurization port 304, the molten metal fills the air entrapped in the cavity and the holes of the generated gas. Due to the movement of filling the vacancies of the molten metal, the flow of the molten metal as a whole is directed from the local pressurizing port to the back of the cavity. The pressure by this local pressurization is applied to the mold in the hot water flow direction from the local pressurization port via the molten metal. A particularly high pressure is applied to the fin molds 306 and 307 near the local pressurizing port in the direction of the flow of the molten metal. However, since the thickness of the fin molds 306 and 307 in the hot water flow direction is increased compared to the fin mold portion 309 that is away from the inlet, the strength is high and deformation and collapse do not occur. By this local pressurization, the thick wall portion cavity 305 and the heat sink body cavity 303 are filled with the molten metal with high density, and a dense heat sink without a cast hole can be manufactured. In addition, since the mold has sufficient strength with respect to the molten metal pressure injection method, the mold life can be extended, and the productivity can be improved and the cost can be reduced.
[0019]
The thick part of the radiator according to the present invention can be used as a fixing part provided with a screw hole or the like for fixing the heating element. Since a thick and high-strength fixing portion can be formed, for example, when used for heat dissipation of a power control device mounted on an automobile, heat dissipation of the power control device can be performed with high reliability even in an environment where vibration is severe.
[0020]
Moreover, the thick part of the heat radiator by this invention can be made into the structure part for contouring a cooling medium path. For example, when heat generated by a power control device mounted on an automobile is radiated to a liquid via a radiator, the radiator is installed in the flow path of the refrigerant liquid. A rational cooling structure can be formed by contouring a part of the flow path with the thick part of the radiator and the heat sink body.
[0021]
Further, the fin mold portion may have a flat plate shape. If the fin mold part has a flat plate shape, the fins of the radiator manufactured by the mold also have a flat plate shape, and a preferable heat radiation characteristic can be exhibited depending on the cooling medium environment to be used.
[0022]
Furthermore, the radiator manufactured by the die-casting mold having these characteristics has a small radiating fin pitch and a thin fin thickness, and thus is small in size and has good radiating characteristics.
[0023]
The embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing a structure of a conventional radiator.
FIG. 2 is a cross-sectional view of a conventional radiator die casting mold.
FIG. 3 is a cross-sectional view of a die cast mold for a radiator according to an embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 100 Radiator, 101 Heat sink body, 102 Radiation fin, 103 Fixing part, 104 Mounting screw, 105 Heating element, 200 Die casting mold for radiator, 201 Upper mold, 202 Lower mold, 203 Heat sink body cavity, 204 Local pressure port, 205 Thick part cavity, 206, 207 Fin mold part near local pressure port, 208 Radiation fin cavity, 209 Fin mold part away from local pressure port, 300 Die casting mold for radiator, 301 Upper mold, 302 Lower mold , 303 Heat sink body cavity, 304 Local pressurization port, 305 Thick part cavity, 306, 307 Fin mold part near local pressurization port, 308 Radiation fin cavity, 309 Fin mold part away from local pressurization port.

Claims (4)

A heat sink body,
A thick part protruding from the heat sink body,
From the heat sink body , a plurality of radiating fin portions protruding in the same direction on the same side as the thick portion with respect to the heat sink body ,
In die casting molds with cavities to mold
A heat sink body, and a thick wall thickness portion from the heat dissipating fin portion, a plurality of heat dissipating fins and, applying station unit pressure to the mold takes molten metal injected into the cavity the local pressure port is thick portion which takes the mold wall thickness portion Provided at a position facing the cavity ,
The die mold for a radiator is characterized in that the fin mold part that molds the heat dissipating fin part in the vicinity of the local pressurizing port has a structure in which the thickness is increased as compared with the fin mold part that is separated from the local pressurizing port. . The die cast mold for a radiator according to claim 1, wherein the thick part is a fixing part that forms a screw hole for fixing to the heating element. The die casting mold for a radiator according to claim 1 or 2, wherein the fin mold part has a flat plate shape. The heat radiator manufactured by the metal mold | die as described in any one of Claim 1 thru | or 3.

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