US Patent 7293388 Adaptive control system

In an insect lure and trap, a system for generating a carbon dioxide attractant has a combustion chamber in which carbon dioxide is generated by means of an exothermic reaction from a gaseous fuel rich in carbon. A container contains a pressurized supply of said fuel and a supply line connects said container to said combustion chamber. A normally closed valve is included in said supply line. The system includes means for sensing the temperature in said combustion chamber and for generating a control signal representative of said temperature. A controller responsive to said control signal compares said temperature to a reference temperature and opens said valve during selected segments of successive equal time intervals.