摘要 |
<p>A coolant supply device for cryostats, comprising a vacuum-jacket siphon with cut-off valve leading from the coolant storage vessel to the cryostat, is fitted at its lower, immersed end, with a remotely operated valve which is operated to connect the siphon inlet selectively to either the coolant or the gas space above it. Specif. the gas enters a sleeve surrounding the siphon pipe, passes downwards and enters the pipe through the valve at its lower end. The system permits improved temp. stability to be achieved in the critical range 4.2-15 degrees K with He, by switching from evaporative to pure gas cooling when desired.</p> |