With the production increase of television CRTs that were 31 inches (787 mm) and above, the manufacturer could no longer afford to scrap the CRTs that became damaged and needed a method to repair them.
Temperature Requirements
Prototype repair methods used convection heat which did not reach high enough temperatures or concentrate the heat sufficiently to complete the annealing process.
Solution
Heat
A Model E4-10 Radiant Heating Chamber applied heat to the glass necks of the broken television CRTs, re-establishing the bond at the broken area and annealing the glass.
Power Control
A Model 664F Phase Angle SCR Power Controller controlled the power to the Radiant Heating Chamber.
System Integration
The Radiant Heating Chamber was installed in a fixture that automatically lowered it over the glass neck of the CRT. The Radiant Heating Chamber and SCR Power Controller were also incorporated into a closed loop control system.
Benefits
Precise Concentrated Heat
The combination of the Model E4 Radiant Heating Chamber and Model 663F Phase Angle SCR Power Controller, integrated into a closed loop control system, provided the precise heat output and concentration required for the annealing process.
Reduced Scrap
The Radiant Heating Chamber gave the manufacturer the capability to repair expensive CRTs that would have previously been scrapped.
