DIFF Subgroup
F23N 3/065 Full Title
Regulating air supply or draught (conjointly with fuel supply F23N1/00) > by conjoint operation of two or more valves or dampers (by power-assisted systems F23N3/08)
F23N 3/065 Regulating air supply or draught (conjointly with fuel supply F23N1/00) > by conjoint operation of two or more valves or dampers (by power-assisted systems F23N3/08)