Finned PTC air heater assembly for heating an automotive passenger compartment

摘要

A heater particularly adapted for use in automotive applications as a passenger compartment heater or the like has a housing with an opening and has a plurality of heat-exchanging fin members and self-regulating electrical resistance heater discs of positive temperature coefficient resistivity (PTC) disposed in the housing to heat air or other fluid which is passed through the housing opening in heat-transfer relation to the fin members. A thermally conductive grease is positioned between the PTC heater discs and fin members to enhance heat transfer. Springs resiliently position the fin members, grease and heater discs in thermally and electrically conductive relation to each other between terminals accessible from the housing exterior to retain the fin members, grease and heater discs engaged during thermal expansion and vibration for reliably energizing the heater discs to heat the fin members over a long service life.