DE1188729B - Cooling device for semiconductor rectifier - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY GERMAN ^ PIW PATENT OFFICE

EDITORIAL

Int. Cl .:

HOIl

Number:
File number:
Registration date:
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German class: 21 g -11/02

C13317 VIII c / 21g

5th July 1956

March 11, 1965

The invention relates to a cooling device for semiconductor rectifiers having at least one with two solid electrodes equipped semiconductor element, in which the developed heat is transferred to metallic, surfaces cooled by boiling a liquid and the resulting Steam condenses on a wall part of the boiler room that is cooled from the outside by the surrounding medium will.

Those made of copper oxide, selenium or the like, which are still in use until recently Materials existing semiconductor rectifiers had a relatively high in the forward direction Resistance and therefore worked with very low current densities. As a result, the surface was the Often rectifier plates separated by spacers to achieve free air circulation sufficient to dissipate the heat generated, and at most one was forced to push the plates through to supplement several cooling fins that enlarge the heat radiation surface five to six times.

The modern semiconductor rectifier, ζ. Β. made of germanium or silicon, on the other hand, have has a very low forward resistance, and is the current density allowed for an element limited by the need to dissipate the generated heat in a very small volume. the The use of large-area ribs in these semiconductor rectifiers does not result in a perfect one Solving the cooling problem as the main part of the temperature difference between the semiconductor element and the surrounding agent is localized to the rib portion that is the effective Element is immediately adjacent.

It has therefore already been proposed to cool these ribs by evaporation of a liquid, what z. B. can be realized according to French patent specification 1 086 791 in that the electrodes of the rectifier by very thick, with massive and very numerous rib-like or hump-like Approaches provided metal body supplemented and over this for contact with a low-boiling point Liquid by arranging the entirety of the rectifier elements thus formed in the liquid container are brought. A semiconductor element is also used for thermal stabilization Rectifier has already been proposed to the semiconductor element with metallic contacts which are cooled by an evaporating liquid and those cooled by the liquid Surfaces have very large dimensions compared to that of the semiconductor element.

Cooling device for semiconductor rectifiers

Applicant:

Compagnie Frangaise Thomson-Houston, Paris

Representative:

Dipl.-Ing. Dipl. Oec. publ. D. Lewinsky,

Patent attorney,

Munich-Pasing, Agnes-Bernauer-Str. 202

Named as inventor:

Charles Beurtheret, Saint-Germain en Laye;

Ernest Rostas, Paris (France)

Claimed priority:

France 6 July 1955 (695 220)

Starting from the type of evaporative cooling known earlier, the invention succeeds for semiconductor rectifiers, an effective cooling device of the type mentioned thereby to create that according to the invention connected to the solid electrodes thick massive extensions in Closed on all sides, partially filled with the cooling liquid, designed as flat cans and closed Boiling and condensation vessels arranged on planes parallel to the electrodes through their broad side protrude, the degree of filling of the boiling and condensation vessels is determined so that at least one of its layers chosen in a perpendicular plane, the thick massive appendages below the liquid level. Due to this arrangement and training is a extremely rapid heat dissipation and thus a maximum of cooling effect achieved. The appendages the flanks of which are freely exposed to the flow of liquid cause both the same surface area as well as a heat transport with the same weight as with the previously known devices of this type, which is much larger compared to them. Furthermore, the proposed here requires cooling device no external organ to effect the refeeding. The present Cooling device work in a steeply inclined position, while in the latter, previously proposed Device has a tendency to be quite dangerous

50a 518/329

3 4

Way are the exact filling of the evaporation channels. The thereby formed vessel 7, one of which

would endanger. Finally, the present cooling connection tab 9 runs out, is attached to two electrodes 2

Device easy to assemble and welded apart, the extensions 5 in its cavity

increase and has in the perpendicular to the electrodes directly opposite each other and from the

right direction an extremely short length, what 5 thereupon filled liquid 6 are surrounded. That

extremely important in the case of stacked equal vessel 7 can then be on a suitable negative pressure

is lighter. to be vented to the atmosphere, and the

Further useful refinements of the rigidity of the whole of the vessel 7 and the electrolytic cooling device and the hollow structure that is buried through it 2 is evident from the following update of the drawing, which touches the end faces Cooling device sets5 and, if necessary, by means of spacers inserted between the parallel lines for semiconductor rectifiers of the vessel walls according to the proposed type,
examples of management illustrated schematically. In the graph according to FIG. 3 are as ordinates

F i g. 1 shows in a partially sectioned side view 15 the at the various points χ of the cooling device

a line provided with large-area cooling fins according to FIG. 1 and 2, 2 a occurring tem-

Power rectifiers of the previously used half-temperatures Θ are applied. Points 11, 12 and 13

ladder type; give in Fig. 3 the correspondingly labeled

F i g. 2 and 2 a partly in the section and partly in th places of the previously used cooling device

Side or front view of one with a cooling system according to FIG. 1, d. H. on semiconductor 1 and on the

Device according to the invention equipped half-weld seam of electrode 2 and cooling fin 4 as well

recognize ladder rectifier; the temperature prevailing at the upper end of the cooling fin

F i g. 3 explains the doors and the ones determined by these points by means of a graph

k manner of FIG. 1 or 2 and 2 a he curve 10 lets the decrease in the cooling effect of

visible cooling devices with regard to the temperature of the middle of the semiconductor 1 after the end of the cooling

temperature distribution on the heat radiating surfaces; rib 4 and the strong temperature gradient of

F i g. 4 a and 4 b give two other versions, the highest heat flow and the smallest In accordance with a center 12 of the cooling device cooling device which is designed according to the invention and has a metal cross-section in side view again. recognize rib 4 from.

In all figures, for the same parts the 30 The increase in the

chosen the same reference number. The cooling effect of the present arrangement is off

In the case of the one shown in FIG. 1 illustrated rectifier of curve 20 in FIG. 3 shows which for the are in a known design with two electrodes 2 device according to F i g. 2 and 2 a with the same oversight disk-shaped semiconductor body 1 in the supplying amount of heat as in the device Enclosed protective housings 3 made of insulating material, and 35 according to FIG. 1 applies. Points 21, 22, 23 and 24 of the the elongated large areas with the electrodes 2 curve 20 indicate the temperatures of the same welded Cooling fins 4 are used to remove digitized points of the device according to FIG. 2 and 2 a, the heat generated during operation of the rectifier. d. H. on the semiconductor 1 and on the surface of the

According to FIG. 2 and 2 a is the rectifier after the metallic extension 5 as well as in the close to this-

F i g. 1 is perfected by the fact that the part of the liquid to be evaporated that is located with the 40 sem

Semiconductor body 1 connected electrodes 2 with keit6 and at the upper end of the flat can 7.

massive frustoconical projections 5 from well As can be seen, the temperature gradient is in the

thermally conductive metal and the ribs 4 electrode in the device according to FIGS. 2 and 2a

by an elongated, vented boiling and coning and the device according to F i g. 1 the same as the

45 curve pieces 21, 22 and 11, 12 in curves 20 have been replaced with a large surface area

and in the interior of the vessel 7, the extensions 5 and 10 are parallel to one another. The temperature in

Electrodes protrude and a vaporizable one, the point 22, i. H. on the surface of the appendix 5

Extensions flushing liquid 6 is filled. is on the other hand a few degrees higher than that in the point

The liquid 6, which only has the lower part of the 23 prevailing boiling point of the liquid 6, The vessel occupies is through the there also 50 and the vessel 7 points over the full extent arranged during operation of the rectifier, its wall has the same boiling point and conheating rate metallic extension 5 brought to boiling condensing temperature. The whole of its upper and the law brought to the same temperature by the great mass and circumference of the surface 5 when the liquid is boiling, the danger barrel 7 of the device according to FIGS. 2 and 2a is therefore one due to the occurrence of Leidenfrost's phenomenon 55 better than the large-area cooling rib 4 of the forenomen induced thermal insulation in the direction of FIG. 1 for heat dissipation from the surface of the appendix avoided. The consumed and the temperature of the semiconductor body 1 standing steam condenses in the upper part 8 is accordingly in the device according to FIG. 2 of the vessel 7, because there the vessel wall through the and 2 a is significantly lower than in the case of the surrounding area Medium, e.g. B. the natural flow device according to FIG. 1. As a result, it results outside air movement or a blown air flow, also a significantly stronger and faster cooling is cooled. and thus a better effect of the rectifier

The one kind of hollow large-area cooling fin elements.

Representative vessel 7 can consist of two identical shells F i g. 4 a and 4 b show two modified

from Z. B. rounded square outline forms of execution of the electrodes 2 complementary

stand along their entire edge, e.g. B. through and from these the heat on the liquid 6

Welding or pressing together, completely transferring, thick, solid metal extensions 5.

gas- and liquid-tight connected to one another According to FIG. 4 a is each electrode 2 with several

Projections 5 formed by milling from a correspondingly thick metal plate with an intersection can be generated. According to Figure 4b, the two opposing electrodes 2 are through two twice as thick plates 5 connected and bridged, with a series of cylindrical perpendicular Holes or with two rows of intersecting holes. The refinements of the Electrodes 2 and the metal body 5 according to FIG. 4 a and 4 b are advantageous when the semiconductor crystals have a large surface area or if the type of rectifier is parallel connection requires multiple crystals.

The rectifier elements equipped with the present cooling device can, as shown in FIG. 2 can be recognized, united with one another in any number and into one rigid, suitable for every one Carrier-attachable multi-cell rectifier are welded.

£ 0

Claims (4)

Patent claims: 1. Cooling device for semiconductor rectifiers with at least one with two solid electrodes equipped semiconductor element, in which the developed heat to metallic, through Boiling a liquid released cooled surfaces and the resulting vapor on a wall part of the boiler room that is cooled from the outside by the surrounding medium is condensed, characterized in that connected to the solid electrodes (2) thick massive projections (5) closed on all sides, partially with the cooling liquid (6) filled, designed as flat cans and arranged in planes parallel to the electrodes Boiling and condensation vessels (7) protrude through their broad side, the degree of filling of the boiling and condensation vessels being determined in this way is that in at least one of their chosen layers in a perpendicular plane, the thick massive extensions are located below the liquid level (Fig. 2, 2 a). 2. Cooling device according to claim 1, characterized in that the boiling and condensation vessels (7) evacuated (Fig. 2, 2a). 3. Cooling device according to claim 1 or 2, for several rectifiers lying one behind the other, characterized in that the thick massive extensions (5) of two facing each other Electrodes of successive rectifier elements in a common boiling and condensation vessel enter and face each other in this face (Fig. 2). 4. Cooling device according to claim 3, characterized in that the in the common Boiling and condensation vessel (7) entering thick massive extensions (5) of two electrodes (2) are combined into a single block (Fig. 4b). Considered publications:
German Patent No. 891425;
U.S. Patent No. 2,703,855. Legacy Patents Considered:
German Patent No. 1026 434. 1 sheet of drawings 509 518/329 3.65 © Bundesdruckerei Berlin