A Mercury Vaporiser Temperature Controller for an Ion Engine

摘要

A system is described which enables the temperature of a mercury vaporiser to be maintained within plus or minus 0.25C of a preset value, within the range of 210C to 260C. For laboratory use the temperature sensor takes the form of a copper/constantan thermocouple, the amplified output of which controls the duty cycle of an astable circuit. This device is used to operate power switches, or an inverter, to drive current through the heating element of the vaporiser. For use in space an alternative system with a platinum resistance thermometer as a sensor is also described. (Author)