TEMPERATURE CONTROL APPARATUS

摘要

This invention relates to temperature control apparatus which has application to the field of electronic space temperature measurement. This temperature control apparatus comprises a temperature sensor and an electronic switch which is switched by the output of the temperature sensor and which controls the operation of heating apparatus. The apparatus includes a voltage converter comprising a nonresistive and non-inductive first series path between a first line and a second line including a first reactor, a first unilaterally conductive device and a second reactor and a second series path between the first and second lines including the first reactor and a second unilaterally conductive device. When an alternating voltage supply is connected across the first and second lines current flows through the first and second series paths maintaining a substantially constant AC voltage across the first reactor and a substantially constant DC voltage across the second reactor to power the electronic switch, and when an open circuit occurs in the second series path no voltage appears across the second reactor. The first and second reactors may be capacitors and the first and second unidirectional devices diodes.