DD221603A1

DD221603A1 - CLAMPING DEVICE FOR SEMICONDUCTOR COMPONENTS OF LARGE PERFORMANCE

Info

Publication number: DD221603A1
Application number: DD26036784A
Authority: DD
Inventors: Manfred Lehmann
Original assignee: Komb Veb Elektro Apparate Werk
Priority date: 1984-02-28
Filing date: 1984-02-28
Publication date: 1985-04-24

Abstract

Die Erfindung betrifft eine Spannvorrichtung fuer Halbleiterbauelemente grosser Leistung, die mindestens einseitig mit einem Kuehlkoerper waermekontaktiert sind, wofuer Spannbolzen mit Spannmuttern sowie Federn zur Kompensation der mechanischen Toleranzen infolge der Verlustleistungswaerme vorgesehen sind. Es ist beabsichtigt durch Einsatz handelsueblicher Federn den technisch-oekonomischen Aufwand zu verringern. Dies wird erreicht, indem jedem Spannbolzen ein Kipphebel zugeordnet ist, dessen Kraftarm ein Mehrfaches des Lastarmes betraegt, und dass weiterhin ein dem Lastarm entgegenwirkender, vorzugsweise als Schraubenfeder ausgebildeter, Kraftspeicher vorzugsweise am freien Ende des Kraftarmes vorgesehen ist. In weiterer Ausbildung ist vorgesehen, dass die Kipphebel entsprechend abgewinkelt sind und zwischen den Kraftarmenden zweier Kipphebel nur ein gemeinsamer, vorzugsweise als Schraubenfeder ausgebildeter, Kraftspeicher vorgesehen ist und dass am Ende des Kraftarmes des einen Kipphebels eine Stelleinrichtung angeordnet ist. Die Anwendung ist fuer dort vorgesehen, wo die Halbleiterbauelemente grosser Leistung unter einem bestimmten Kontaktdruck mit den Kuehlkoerpern verbunden werden muessen. Fig. 4The invention relates to a clamping device for semiconductor devices of great power, which are thermo-contact with at least one side with a Kuehlkoerper, for which clamping bolts are provided with clamping nuts and springs to compensate for the mechanical tolerances due to the loss of heat. It is intended to reduce the technical-oeconomic effort by using commercial springs. This is achieved by each clamping bolt is associated with a rocker arm, the force arm is a multiple of the load arm, and further that a load arm counteracting, preferably designed as a helical spring, energy storage is preferably provided at the free end of the power arm. In a further embodiment it is provided that the rocker arms are angled accordingly and between the power arm ends of two rocker arms only a common, preferably designed as a helical spring, power storage is provided and that at the end of the power arm of a rocker arm an adjusting device is arranged. The application is intended for where the semiconductor devices of high power have to be connected to the cooling bodies under a certain contact pressure. Fig. 4

Description

-3- 260 367-3- 260 367

Spannbolzen 2 wird noch eine Spannfeder 3 aufgenommen, die entgegen der Spannrichtung vorgespannt ist und zwischen den Spannbolzen vorzugsweise gegen einen hervorgehobenen Punkt eines Teiles des Kühlkörpers 1 wirkt. Der gleiche konstruktive Aufbau ist in Fig. 2 zu erkennen. Statt der Blattfeder 3 sind hier Tellerfedern 4 auf die Spannbolzen 2 als Federpaket aufgebracht. Die Nachteile zu beiden Lösungen wurden bereits in der Beschreibungseinleitung behandelt. Die Fig.3 und 4zeigen ebenfalls einen zweiteiligen Kühlkörper 1, der ein Halbleiterbauelement in sich einschließt und durch Spannbolzen 2 zusammengespannt wird. In Fig.3 sind auf die Spannbolzen 2 noch Kipphebel 5 mit gegen den Kühlkörper 1 gerichteten Kippunkten 6 aufgebracht. Die Kippunkte bestimmen das Verhältnis Kraftarm K: Lastarm L derart, daß der Kraftarm K um ein Mehrfaches langer ist als der Lastarm L. Gegen die Kraftarme K der Kipphebel 5 wirken Druckfedern 7, die sich gegen einen festen Punkt außerhalb des Kühlkörpers 1 abstützen. In Fig.4 sind die Kipphebel 5 abgewinkelt und die Enden ihrer Lastarme über eine Stelleinrichtung 9 mit einer Zugfeder 8 beaufschlagt. Auch hier sind die Kraftarme K der Kipphebel 5 um ein Mehrfaches langer als ihre Lastarme L. Die vorteilhafte Wirkungsweise der erfindungsgemäßen Spannvorrichtung ist unschwer zu erkennen. Bedingt durch die entsprechend auszubildenden Kipphebel 5 (Kraftarm:Lastarm) können die an den normgerechten, handelsüblichen Schraubenfedern angreifenden Kräfte auf ein solches Maß reduziert werden, da sowohl die Druck- wie auch die Zugfedern den auftretenden Belastungen standhalten.Clamping pin 2 is still a tension spring 3 is added, which is biased against the clamping direction and preferably acts between the clamping bolt against a highlighted point of a portion of the heat sink 1. The same structural design can be seen in Fig. 2. Instead of the leaf spring 3 disc springs 4 are applied to the clamping bolt 2 as a spring assembly here. The disadvantages of both solutions have already been dealt with in the introduction to the description. Figures 3 and 4 also show a two-part heat sink 1, which includes a semiconductor device in itself and is clamped together by clamping bolt 2. In Figure 3 tilting lever 5 are still applied to the clamping bolt 2 with directed against the heat sink 1 tilting points 6. The tilting points determine the ratio of force arm K: load arm L such that the force arm K is several times longer than the load arm L. Against the force arms K of the rocker arm 5 act compression springs 7, which are supported against a fixed point outside the heat sink 1. In Figure 4, the rocker arm 5 are angled and the ends of their load arms acted upon by an adjusting device 9 with a tension spring 8. Again, the force arms K of the rocker arm 5 are many times longer than their load arms L. The advantageous operation of the clamping device according to the invention is easy to recognize. Due to the appropriately trained rocker arm 5 (power arm: load arm) acting on the standard, commercial coil springs forces can be reduced to such an extent, since both the pressure and the tension springs to withstand the loads occurring.

Die in Fig.4 dargestellte Lösung bietet noch den zusätzlichen Vorteil eines gleichmäßigen Kraftansatzes an beiden Spannbolzen 2, sowie einer Feinregulierung und Nachstellmöglichkeit durch die vorgesehene Stelleinrichtung 9.The solution shown in Figure 4 still offers the additional advantage of a uniform force approach to both clamping bolts 2, as well as a fine adjustment and readjustment by the proposed adjusting device. 9

Claims

1. Clamping device for semiconductor devices, which are thermally contacted at least on one side with a heat sink, for which clamping bolts are provided with clamping nuts and energy storage to compensate for the mechanical tolerances due to the heat loss heat, characterized in that each clamping bolt (2) is associated with a rocker arm (5) Force arm (K) is a multiple of the load arm (L), and further that the load arm (L) counteracting, preferably as a helical spring (7; 8) trained, energy storage is preferably provided at the free end of the power arm (K).

2. Clamping device according to item 1, characterized in that the rocker arms (5) are angled accordingly and between the Kraftarmenden (K) of two rocker arms (5) only a common, preferably as a helical spring (7, 8) trained, energy storage is provided.

-2- 260 367

Invention claims:

3. Clamping device according to item 2, characterized in that an adjusting device (9) is arranged at the end of the power arm K of a rocker arm (5).

For this 2 pages drawings

Field of application of the invention

The invention relates to a clamping device for semiconductor devices of high power, which are heat-contacted at least on one side with a heat sink, for which Spännbolzen are provided with clamping nuts and energy storage to compensate for the mechanical tolerances due to the heat loss line.

The application of the invention is useful only in clamping devices for semiconductor devices large power, which connect them under a certain contact pressure with heat sinks for air or liquid cooling.

Characteristic of the known technical solutions

It is common to provide semiconductor devices for high power on one or two sides with heat sinks for air or liquid cooling in order to dissipate enough power loss heat from the semiconductor device can. This in turn requires good thermal contact between the semiconductor device and the heat sink, which is achieved by means of a clamping device whose clamping bolts produce a relatively high defined contact pressure. Due to the operational heating of the semiconductor devices whose heat loss through the heatsink also reaches the parts of the clamping device, arise within this functional unit material expansions that no longer ensure the defined contact pressure. To counteract this, it is customary to provide spring elements between the tensioning device and the heat sink, which absorb the loss-heat-related material expansions and thereby constantly ensure a nearly equal contact pressure. In this case, these spring elements must be designed so that they absorb or transfer the entire contact pressure and compensate for the differences in the thermal expansion of the individual components such as semiconductor device, heat sink and clamping device. It is also of particular importance that ensure the spring elements during the Verspannvorganges a uniform force distribution to the individual clamping bolt. As spring elements sheet or disc springs, often also stacked into packages, are usually used.

Although the leaf springs mentioned can ensure a uniform force action on the clamping bolts by virtue of their arrangement (FIG. 1), since they are not offered as standard parts but are custom-made, they require a greater economic outlay. The disc springs (Fig. 2), however, are standard parts, but they in turn require a high technical effort for spring guidance (calibration) in the package formation, so that cover the edges of the disc springs exactly to obtain the desired spring force. Since these spring assemblies are expediently assigned to the clamping bolt, the distribution of the force on the individual clamping bolts is considerably more difficult. Due to the short travel of the disc springs, a large number of them must be used to achieve the required travel. The increased technical complexity of the mentioned disadvantages also requires higher costs, which are not negligible. Further, still known springs have not found any use for these clamping devices, since they are structurally no longer suitable for the clamping device in such an embodiment that they can withstand a contact pressure of 70ΌΟ-15,000Ν.

Object of the invention

The aim of the invention is to reduce the technical-economic effort for the mentioned clamping devices.

Explanation of the essence of the invention

The invention has for its object to modify the clamping device constructively so that other springs, which are available as standard commercial parts. Can be used.

This is achieved according to the invention in that each clamping bolt is assigned a rocker arm, whose power arm is a multiple of the load arm, and that further a load arm counteracting, preferably designed as a helical spring, energy storage is provided at the free end of the power arm.

In a further embodiment of the invention is then still provided that the rocker arms are angled accordingly and between the power arm ends of two rocker arms only a common, preferably designed as a helical spring, power storage is provided.

embodiment

The invention will be explained in more detail with reference to exemplary embodiments.

They show:

Fig. 1: Known tensioner with leaf spring

Fig. 2: Known tensioner with plate spring package

Fig.3: Inventive tensioning device with coil spring for pressure load

4: Tensioning device according to the invention with a helical spring for tensile load. The prior art is shown symbolically in FIGS. 1 and 2. Fig. 1 shows a two-part heat sink 1, which includes a semiconductor device 10 and the two parts are clamped together by clamping bolt 2. Of the