Gas burner

A gas burner comprising:

• an inner gas outlet member with a plurality of inner gas outlets formed therein;
• an inner gas delivery pipe disposed under the inner gas outlet member and having an inlet, an outlet communicated with the inner gas outlets, two interconnected tubular sections movable relative to each other so as to adjust length of the inner gas delivery pipe, and a locking unit for releasably interlocking the tubular sections;
• an annular outer gas outlet member with a plurality of outer gas outlets formed therein;
• several outer gas delivery pipes disposed under the outer gas outlet member, each of the outer gas delivery pipes having an inlet, an outlet communicated with the outer gas outlets, two interconnected tubular sections movable relative to each other so as to adjust length of the outer gas delivery pipe, and a locking unit for releasably interlocking the tubular sections of the outer gas delivery pipe;
• a head seat disposed under the inner and outer gas delivery pipes and including a first gas supply pipe adapted to accept a combustible gas from a gas supply source, and a second gas supply pipe connected securely to the first gas supply pipe and adapted to accept the combustible gas from the gas supply source;
• several first nozzles installed on the first gas gas supply pipe and spaced apart from the inlets of the outer gas delivery pipes respectively so as to direct the combustible gas from the first gas supply pipe to the inlets of the outer gas delivery pipes, each of the first nozzles being associated with a corresponding one of the outer gas delivery pipes to define a first air mixing space therebetween;
• a second nozzle installed on the second gas supply pipe and spaced apart from the inlet of the inner gas delivery pipe so as to direct the combustible gas from the second gas supply pipe to the inlet of the inner gas delivery pipe, the second nozzle and the inner gas delivery pipe together defining a second air mixing space therebetween;
• and
• a burner head unit coupled with and disposed above the inner and outer gas delivery pipes and having an air inlet unit which is formed in an outer surface of the burner head unit between the outer gas outlet member and the head seat in communication with the first and second air mixing spaces;
• whereby, the combustible gas coming from the first and second nozzles is mixed with air in the first and second air mixing spaces, and flows out of the inner and outer gas outlet members through the inner and outer gas delivery pipes.