(under subclass 722) Device having a plurality of combustion zones distinguished by the fuel-oxidizer ratio supplied to each zone for combustion therein, and wherein an amount of fuel in excess of that required for stoichiometric combustion is supplied to a first fuel-rich zone for combustion, and to the product of that combustion, and downstream of the first zone, additional fuel or air is added for combustion at one or more locations in what is considered an additional zone or zones whereby the total combustion process of the device is staged.
(1) Note. Excluded from this subclass are those devices provided with a separate fuel-rich combustion zone which serves only as an igniter or initiator such as a pilot flame; see this class (60), subclass 39.82.
SEE OR SEARCH THIS CLASS, SUBCLASS:
39.06, for methods of fuel injection.
739, for manifold means supplying a plurality of separate injectors as least two of which inject fuel into separate combustion zones.
746+, for plural, distinct, spaced injectors for plural distinct combustion zones.
SEE OR SEARCH CLASS 431, Combustion,
10, for means to add an oxidizer to a region of incomplete combustion.
