Pulverized-coal and liquid-fuel dual-purpose burner

Claim 1

A pulverized-coal and liquid-fuel burner comprising: a main body including: a front member comprising an outer pipe, an intermediate pipe, and an inner pipe, said pipes being coaxially and telescopingly arranged, said outer pipe including a secondary-air inlet in a lower side thereof, and said intermediate pipe including a primary-air inlet located adjacent said secondary-air inlet and adjacent a rear end of said inner pipe, said outer, intermediate, and inner pipes including holes at their rear ends, which holes are aligned, a threaded liquid-fuel inlet pipe extending through said holes and projecting beyond said outer pipe, said liquid-fuel inlet pipe securing said inner pipe within said intermediate pipe, a discharge nozzle attached to a front end of said inner pipe, and a rear member formed integrally with said intermediate pipe and including a port disposed on an upper side of a rear end thereof for the reception of pulverized coal, a flame spout detachably secured to the front end of said main body and tapering-down in diameter toward its discharge end, said flame support including a peripheral wall having a plurality of holes therein spaced rearwardly from the discharge end of said flame spout, an air inlet pipe joined to said front member in encompassing relationship to said primary-air and secondary-air inlets for introducing air into said outer and intermediate pipes, said air inlet pipe being inclined toward said rear member so as to be disposed at an inclined angle relative to the axis of said front member, said air inlet pipe being divided into one primary air duct and one secondary air duct by a partition wall, both air ducts having an air regulating valve assembled therein, a supporting sleeve connected to a rear end of said rear member by removable fasteners, bearings mounted in front and rear ends of said supporting sleeve, a driven shaft mounted within said bearings so as to be aligned with said inner pipe, said shaft including a helical screw at a front end thereof to define a screw conveyor for conveying pulverized coal forwardly from said port, a front end of said screw thread terminating immediately adjacent said rear end of said inner pipe and said primary-air inlet and means for rotating said shaft.