JPH02206151A - Semiconductor cooler of heat-pipe system - Google Patents

Abstract

PURPOSE:To make an electrically insulating property high, to make a heat-dissipating property and a heat-absorbing property excellent by a method wherein many fins are inserted and attached to a heat pipe in order to use them as a heat-dissipating part, a heat pipe inserted and attached to a metal block at the lower part is used as a heat-absorbing part and an intermediate part is connected by using an electrically insulating cylinder. CONSTITUTION:The tip of a heat pipe 1 whose one end has been narrowered to be a semispherical shape or a conical shape is provided with a nozzle 6; many fins 2 are inserted and attached to the heat pipe where many stripe grooves at an angle inclined to one side in an axial direction at an inner face are installed; a heat-dissipating part is formed. A heat pipe 1' whose one end has been throttled to be the semispherical shape or the conical shape and has been sealed by a welding operation and which is provided with many crossed stripe grooves in an axial direction at an inner face is inserted and attached to a metal block 3; a heat-absorbing part is formed. An intermediate part between the heat-dissipating part and the heat-absorbing part is connected by using an electrically insulating cylinder 7 provided with a flange made of an ironnickel alloy; an electrically insulating liquid such as Freons or the like is filled as a working liquid of the heat pipe. Thereby, an electrically insulating property becomes excellent; a heat-absorbing property and a heat-dissipating property are enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improved heat pipe type semiconductor cooler.

[Prior art and its problems] A cooling endothermic section using a heat pipe for cooling semiconductors such as Cyrisk was disclosed in Japanese Patent Application Laid-Open No. 60-579 by the present inventors.
It is already known as No. 56.

As shown in FIGS. 5 and 6, this semiconductor heat pipe cooling endothermic part consists of a heat pipe (1) made of a metal with good thermal conductivity such as copper, and a fin (2) made of copper or aluminum with good thermal conductivity. ) is inserted to form a heat dissipation part, the lower end of the heat pipe is inserted to a metal block (3) made of copper etc. with good heat conduction, and a semiconductor (4) such as Cyrisk attached to the metal block generates heat. The generated heat is transferred to a heat pipe and cooled naturally by fins or forcibly by a fan, increasing the efficiency of the semiconductor.

Note that a terminal (5) for taking out current is attached as necessary. Semiconductor surfaces of thyristors and the like usually have a potential, and as a result, electricity is passed through the metal heat pipe to the heat dissipation section, making handling extremely dangerous depending on the environment in which they are used. Particularly recently, they have been sometimes installed in vehicles such as trains, which has caused safety problems. Therefore, an attempt has been made to provide electrical insulation by installing an insulating plate (9) made of ceramic such as aluminum nitride, which has relatively good thermal conductivity, between the semiconductor (4) such as Cyrisk and the metal block. However, the above-mentioned aluminum nitride still has problems in terms of thermal performance, mechanical strength, reliability, etc.

[Problem to be solved by the invention]

As a result of studies on the above-mentioned problems, the present invention has developed a heat pipe type semiconductor cooler that has excellent electrical insulation and improved heat absorption and heat dissipation properties.

[Means and effects for solving the problem] The present invention forms a heat dissipation section by inserting a large number of fins into one or more heat pipes having a large number of grooves inclined in one direction in the axial direction on the inner surface. , one or more heat pipes having a large number of intersecting grooves in the axial direction on the inner surface are inserted into the metal block to form a heat absorbing part, and the intermediate between the heat dissipating part and the heat absorbing part is electrically connected. This is a heat pipe type semiconductor cooler that is connected by an insulating tube and has an electrically insulating working fluid.

That is, in the present invention, for example, as shown in FIG. 1, one end of a heat pipe (1) has a nozzle (6) at the tip thereof which is constricted into a hemispherical or conical shape, and the inner surface thereof has a nozzle (6) as shown in FIG. Axial direction (1
) A heat dissipation section is formed by inserting a number of fins (2) into one or more heat pipes provided with a large number of grooves (M) at an inclined angle (α) on one side of the heat pipe, and one end is placed below the heat pipe. is squeezed into a hemispherical or conical shape and sealed by welding, and the inner surface has many grooves (N) in the shape of a 7-shape, a concave shape, or a wavy shape intersecting in the axial direction as shown in Fig. 4. A heat absorption part is formed by inserting one or more heat pipes (1') having a metal block (3) into the metal block (3), and a flange made of iron-nickel alloy or the like is provided between the heat radiation part and the heat absorption part. c? ) The heat pipe type semiconductor cooler is made by connecting the heat pipes with an electrically insulating tube and sealing in an electrically insulating material such as fluorocarbon as the working fluid for the heat pipe.

The shape of the groove (M) provided on the inner surface of the heat pipe (1) of the heat dissipation part may be V-shaped, concave-shaped, or wave-shaped, and as shown in FIG. It has an angle (α) inclined to one side, and this angle (α) is preferably in the range of 2 to 10°. The above-mentioned grooves expand the surface area of the inner surface of the heat pipe to promote condensation characteristics, and improve the reflux of the working fluid to improve heat dissipation characteristics.

In addition, grooves (
The shape of N) may be V-shaped, concave, or wavy, but as shown in FIG. 4, grooves are provided that intersect in the axial direction. The angle is preferably 2 to 45 degrees inclined in the axial direction. These grooves increase the surface area, promote boiling characteristics of the working fluid, and improve endothermic action.

In addition, an electrically insulating tube (7) made of, for example, alumina, magnesia, glass, or ceramic is connected between the heat dissipating section and the heat absorbing section to block electrical leakage from the semiconductor in the heat absorbing section. Make sure that the current does not reach the heat sink. Therefore, only the heat is transferred without the electric potential of the SIRISK being transferred to the heat radiating part, thereby preventing dangers such as electric shock.

Thermal performance is also improved because the semiconductor can be attached directly to the metal block.

Note that the connection between the electrically insulating cylinder and the heat pipe described above can be better achieved by using a sealing material such as an iron-nickel alloy.

Therefore, it is preferable that the heat pipe constituting the heat dissipation section has its upper end constricted into a hemispherical or conical shape and has a nozzle (6) at its tip. Then, since the grooves provided on the inner surface of the heat vibe extend to the ends, the efficiency of the heat pipe is increased. The nozzle at the tip is for injecting hydraulic fluid. Furthermore, the reason why the lower end of the heat pipe in the heat absorption part is constricted into a hemispherical or conical shape is because the grooves provided on the inner surface of the heat vibe extend to the end, as in the case of the heat radiation part described above, which improves evaporation efficiency. It will improve.

In addition, in the heat pipe type semiconductor cooler of the present invention, the heat pipe may be placed either vertically or horizontally, and even when the heat pipe is placed horizontally, the grooves are provided on the inner surface of the heat pipe, so that the grooves function effectively as a wick. This improves heat dissipation characteristics. The heat pipes used in the heat radiating section and the heat absorbing section may have the same diameter, but for example, the heat pipe (1') in the heat absorbing section may have a larger diameter than the heat pipe (1) in the heat radiating section to achieve a better heat absorption effect. It can also be improved.

Furthermore, the heat pipe can be made of copper, aluminum or stainless steel, and the metal blocks and fins are made of copper, aluminum, or other materials with good thermal conductivity.

As described above, according to the present invention, even if a semiconductor (4) such as a thyristor is directly attached to the surface of the metal block (3), the electric potential of the thyristor is reduced because it is electrically insulated by the electrically insulating tube (7) in the middle of the heat pipe. Because only the heat is transferred without being transferred to the heat radiating part, dangers such as electric shock can be prevented. Thermal performance is also improved because the semiconductor can be attached directly to the metal block.

In addition, special grooves are provided on the inner surfaces of the heat pipe (1) in the heat dissipation part and the heat pipe (1') in the heat absorption part, so that the heat dissipation and heat absorption properties are further improved.

Since the end of the heat pipe is formed into a hemispherical or conical shape, the grooves extend to the end, which increases the effective area and improves the performance of the heat pipe compared to those with flat ends. It is something.

Furthermore, since the heat pipe is provided with a nozzle (6) having a pore, it has many advantages, such as improved workability in injection and sealing of the working fluid.

〔Example〕

An embodiment of the present invention will be described below.

The height of the mountain on the inner surface is 0.3 mm, the pitch is 0.9 tna 7
The groove shown in Fig. 3 has a shape of
The upper end of the copper pipe with an outer diameter of 22.23 tm was formed into a hemispherical shape by spinning, and a nozzle (6) with a small hole was provided at the tip by spinning to form a heat dissipation part. Let it be a heat pipe (1). Next, the height of the mountain is 0.3m++ on the inner surface of the copper pipe of the same diameter.
V-shaped with a pitch of 0.98 and 5″ on both the left and right sides in the axial direction
An inclined groove (N) as shown in FIG. 4 is provided, and the tip thereof is similarly formed into a hemispherical shape by spinning and sealed by welding to form a heat pipe (1') of the heat absorption section. Alumina insulation (+7) with an Fe-Ni alloy flange (not shown) is installed between this heat pipe (1') and the heat pipe (1) of the heat dissipation section. (1) and (1') were connected and integrated. Next, as shown in Figure 1, one end of this integrated heat pipe is 120 m long.
After inserting the a+ into the perforated copper metal block (3) and brazing it with soft solder, the nozzle at the upper end of the heat pipe (
After deaerating non-condensable gas such as air from 6), a certain amount of electrically insulating working fluid (8) such as Freon is injected into the nozzle (6).
After crimping with a crimping jig and welding the crimped upper end by TIG welding, a number of copper fins (2) were inserted at appropriate pitches above the heat pipe to form a heat radiating section. Note that after the steel pipe with an insulating tube is made into a heat pipe, it may be brazed to the block. In this case, the nozzle is downward (inside the block)
can be placed in

As shown in Fig. 1, the heat pipe type semiconductor cooler manufactured in this way has a heat pipe (1) with a large number of fins (2) inserted therein to form a heat dissipation section, and a metal block (3 ) is inserted into the heat pipe (1') to form a heat absorbing part, and an electrically insulating cylinder (7) is connected between the heat pipes (1').

The heat generated by semiconductors (4) such as Cyrisk is generated by metal blocks (
3) to the heat pipe (1'), and is radiated by the heat radiating section of the heat pipe (1). At this time, since the electrically insulating tube (7) is provided, only heat is transferred to the upper heat radiating section, and since it is electrically insulated, there is no risk of electric shock. Furthermore, since an electrically insulating material such as Freon is used as the working fluid, safety is ensured in this respect as well. The heat pipe (1) of the heat dissipation section is provided with a 7-shaped spiral groove on its inner surface as shown in Figure 3, which improves heat dissipation.
') is provided with spiral grooves that cross left and right as shown in FIG. 4, so that heat absorption is improved.

〔effect〕

As explained above, according to the present invention, a heat pipe type semiconductor cooler having high electrical insulation properties and excellent heat dissipation and heat absorption properties can be obtained, which has a significant industrial effect.

[Brief explanation of the drawing]

Fig. 1 is a front view of a heat pipe type semiconductor cooler showing an embodiment of the present invention, Fig. 2 is a plan view of Fig. 1, and Fig. 3 shows the inner surface of the heat pipe (1) shown in Fig. 1. 4 is a sectional perspective view showing the inner surface of the heat pipe (1') shown in FIG. 1, FIG. 5 is a front view of a conventional heat pipe type semiconductor cooler, and FIG. In the top view of the figure, No. 7 @ is a front view of another conventional heat pipe type semiconductor cooler. 1.1'...Heat pipe, 2...Fin,
3...Metal block, 4...Semiconductor, 5...
・Terminal, 6... Nozzle, 7... Electrical insulation tube, 8
... Hydraulic fluid.

Claims (1)

[Claims] A heat dissipation section is formed by inserting a large number of fins into one or more heat pipes having a large number of grooves inclined in one direction in the axial direction on the inner surface. One or more heat pipes having grooves are inserted into a metal block to form a heat absorption part, and the middle of the heat radiation part and the heat absorption part is connected with an electrically insulating tube, and the working fluid is electrically insulated. A heat pipe type semiconductor cooler characterized by the fact that it is a heat pipe type semiconductor cooler.