Abstract: Self-triggering cryogenic heat flow switches are used particularly with cooling systems that require a redundant operation. The self-triggering cryogenic heat flow switch has the simplest possible construction while providing a reliable, maintenance-free mode of operation, and ensures a self-switching connection between a heat sink and an end use device or application that is to be cooled. The heat flow switch includes an outer hollow cylinder 1 that is connected with a heat sink 9, and an inner body 2 that is arranged coaxially to the outer hollow cylinder 1 and connected to the end use device or application to be cooled. When the heat sink 9 is switched off, a concentric annular gap 4 fixed by spacers is provided between the hollow cylinder 1 and the inner body 2.

Abstract: A cooling apparatus especially for cooling high-temperature-superconducting lectronic components includes a cold gas cooling machine, such as a Stirling machine, thermally connected to a pressure vessel serving as a cold reservoir vessel. The pressure vessel contains a working medium having a triple point in the temperature range from about 60K to about 90K and a critical temperature at least as high as the maximum operating room temperature of the apparatus. The working medium is propane, for example. A cooling surface of the electronic component is thermally connected to the pressure vessel. In the method of operating the apparatus, the electronic component does not require continuous cooling. During a charging or refrigerating phase, the cooling machine freezes the working medium. Then during a useful cooling phase, the cooling machine is switched off and the electronic component is operated while being cooled by the frozen working medium.