A controlled magnetic clamp

Abstract

A clamp for creating the thermal contact in vacuum between components of the cryostat on its preliminary cooling is described. The contact is established when heating conduits are pressed towards one another by a permanent magnet and is broken (established) when current pulses of appropriate polarity are applied to the winding around the iron magnetic conductor. In the open state, the unit is held by a spring. In a temperature range of 80–4 K, the heat flow through the pressed contacts varies from 2 W to several milliwatts.