High speed film processor with temp control - has resistive thermometers controlling variable heaters and coolers via electronic conversion ccts.

摘要

The temp. control system for the various solution tanks is designed to maintain temperatures accurately within narrow limits especially for high speed processing. The analogue signals from the thermometers are converted into digital values and applied to one input of a comparator circuit whose other input represents a reference signal. One output from this stage is used to control the variable switched heaters, the other output is connected to the cooling system valves. The design is claimed to maintain temperatures within a range of approximately 1 deg.C.