PRINTED CIRCUIT BOARD COOLING SYSTEM EMPLOYING BELLOWS AND LAYER OF THERMAL GREASE AND METHOD FOR FORMING THE LAYER

摘要

25307-192 A cooling system used with a printed circuit board having at least a solid circuit component thereon, comprising a cooling header and cooling modules connected to the cooling header. Each of the cooling modules engages one of the components. The cooling module has a heat transfer plate connected to one end of a bellows which is connected to the cooling header at the other end. A layer of thermally conductive compound such as a layer of thermal grease is interposed between the heat transfer plate and the corresponding circuit component. The thermally conductive layer is initially pressed with a pressure higher than a critical pressure, and thereafter, the pressure is reduced to working pressure exerted on the circuit component provided by the resilient force of the bellows and the hydraulic pressure of the coolant. The critical pressure is predetermined experimentally. As a result, the thermal contact resistance between the heat transfer plate and the circuit component is favorably reduced and stabilized.