DIFF Subgroup
F02D 19/0639 Full Title
Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures (the non-fuel substances being gaseous F02D21/00) > peculiar to engines working with pluralities of fuels, e.g. alternatively with light and heavy fuel oil, other than engines indifferent to the fuel consumed
Of 2 combined children, 0 exist in both systems.
2 codes are CPC-only extensions.