Abstract: A self-regulating flexible heater for automobiles and other vehicles which is comprised of a breathable substrate (10) to which is applied a coating (14) of a conductive material and a coating (12) of positive temperature coefficient material.

Abstract: A dual-purpose combustor for ordinary combustion and pulse combustion especially suited to be installed for a spray dryer, which is used not only as an ordinary combustion gas generator but also as a pulse combustion gas generator capable of generating high frequency sound waves and hot blast in large capacity to enhance the drying efficiency. The dual-purpose combustor is composed essentially of successionally connected chambers: a concentric narrow ring form fuel/combustion air mixed gas supply slit, a concentric wider ring form combustion chamber having an ignition means and a narrow outlet portion, a concentric narrow ring form exhaust gas chamber, a concentric wider ring form upper secondary combustion chamber, and a concentric cylindrical form lower secondary combustion chamber having the same diameter with the outer diameter of the concentric ring form upper secondary combustion chamber.