A DEVICE FOR HEATING TOOLS IN THERMOFORMING

摘要

The invention relates to a device for heating tools (1) in thermoforming. The tool (1) which fixedly retains a thermoplastic blank (9) on the forming of a plastic end wall on a packaging container may be heated to the softening temperature of the thermoplastic with the aid of a number of PTC resistor elements (2) disposed in the tool (1). Both contact surfaces (3) of the PTC resistors (2) are in contact with different parts (6, 7) of the tool and these parts are, in turn, connected to an external current source.